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  • 51.
    Al-Amiry, Bariq
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences. Karolinska Univ Hosp, Dept Radiol, Stockholm, Sweden.
    Mahmood, Sarwar
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Krupic, Ferid
    Sayed-Noor, Arkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Leg lengthening and femoral-offset reduction after total hip arthroplasty: where is the problem - stem or cup positioning?2017In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 58, no 9, p. 1125-1131, article id UNSP 0284185116684676Article in journal (Refereed)
    Abstract [en]

    Background: Restoration of femoral offset (FO) and leg length is an important goal in total hip arthroplasty (THA) as it improves functional outcome. Purpose: To analyze whether the problem of postoperative leg lengthening and FO reduction is related to the femoral stem or acetabular cup positioning or both. Material and Methods: Between September 2010 and April 2013, 172 patients with unilateral primary osteoarthritis treated with THA were included. Postoperative leg-length discrepancy (LLD) and global FO (summation of cup and FO) were measured by two observers using a standardized protocol for evaluation of antero-posterior plain hip radiographs. Patients with postoperative leg lengthening >= 10mm (n = 41) or with reduced global FO >5mm (n = 58) were further studied by comparing the stem and cup length of the operated side with the contralateral side in the lengthening group, and by comparing the stem and cup offset of the operated side with the contralateral side in the FO reduction group. We evaluated also the inter-observer and intra-observer reliability of the radiological measurements. Results: Both observers found that leg lengthening was related to the stem positioning while FO reduction was related to the positioning of both the femoral stem and acetabular cup. Both inter-observer reliability and intra-observer reproducibility were moderate to excellent (intra-class correlation co-efficient, ICC >= 0.69). Conclusion: Post THA leg lengthening was mainly caused by improper femoral stem positioning while global FO reduction resulted from improper positioning of both the femoral stem and the acetabular cup.

  • 52.
    Al-Amiry, Bariq Sh.
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Gaber, John F.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Kadum, Bakir K.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Brismar, Torkel B.
    Sayed-Noor, Arkan S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    The Influence of Radiological Severity and Symptom Duration of Osteoarthritis on Postoperative Outcome After Total Hip Arthroplasty: A Prospective Cohort Study2018In: The Journal of Arthroplasty, ISSN 0883-5403, E-ISSN 1532-8406, Vol. 33, no 2, p. 436-440Article in journal (Refereed)
    Abstract [en]

    Background: We aimed to investigate the influence of preoperative radiological severity and symptom duration of hip osteoarthritis (OA) on the postoperative functional outcome, quality of life, as well as abductor muscle strength after total hip arthroplasty (THA). Methods: In this prospective cohort study, we studied 250 patients. Preoperatively, we evaluated the function with the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index and quality of life with euroqol-5D (EQ-5D). At 1 year after THA, the same scores and also hip abductor muscle strength were measured in 222 patients. We divided the cohort twice, first according to the radiological OA severity [Kellgren-Lawrence classification (KL)] and then according to the OA symptom duration. We investigated whether the preoperative KL class and symptom duration influenced the 1-year WOMAC (primary outcome measure) or EQ-5D and abductor muscle strength (secondary outcome measures). Results: The crude results showed that KL class and symptom duration had no influence (P = .90 and P = .20, respectively) on the 1-yearWOMAC. Younger age, male gender, and lower body mass index were associated with a better function. Regarding 1-year EQ-5D, the crude results showed that body mass index and KL class had no influence (P = .83 and P = .39, respectively). The adjusted results showed that only age and gender influenced the postoperative EQ-5D. No influence of the tested factors was found on the 1-year abductor muscle strength. Conclusion: Preoperative radiological OA severity and symptom duration had no influence on the outcome of THA and should probably not affect the decision about timing the operative intervention. 

  • 53.
    Albadi, Danial
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Changes in the treatment of cervical hip fractures at Umeå University Hospital2018Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 54.
    Albertsson, Pontus
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences.
    Occupant casualties in bus and coach traffic: injury and crash mechanisms2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background: The relevance of conducting this thesis is evident by the fact that bus and coach casualties have been “stubbornly stable” in Europe recent years and a need for investigating if a similar trend could be found in Sweden is therefore obvious. It was also important to add new knowledge to the bus and coach research in Sweden, since many areas were scarcely addressed.

    Aims: To describe bus and coach occupants’ injuries, crash and injury mechanisms generated in a traffic environment based on data from the medical sector. Additional aims were to investigate the injury reducing effect of a 3-point belt, the effect of cross-winds, and crucial factors in the emergency- and rescue response.

    Material and methods: Injury data analyses were based on a complete ten-year medical data set from a catchment-area with about 130,000 inhabitants. A number of crash studies with the scope in different crash phases were conducted by applying and elaborating the Haddon matrix as a framework. An additional framework, Protocol for Major Incidents was used in order to investi-gate the emergency- and rescue response to a severe coach crash.

    Results: Between the first and second five-year period, the incidence of injured in non-crash in-cidents was increased by 24%. In non-crash incidents, 54% were injured; 2/3 while alighting from a bus or coach. The pre-crash factor cross-wind, in addition to vehicle design, vehicle speed and road friction, was investigated in ten crashes. It was confirmed that cross-wind, in relation to vehicle speed and slippery road conditions, needs more attention. The importance of goods load-ing and passengers’ position in the bus, was indicated by the fact that a displacement of the cen-tre of mass rearwards with 10% increased the necessary coefficient of friction with, on average 45%, which in many cases corresponded to dry road conditions. Three Swedish rollover crashes were analysed with regard to the injury outcome, mechanisms and the possible injury reduction for occupants using a safety belt. A considerable increase in safety for occupants belted with 3-point belts was shown through limiting interior contacts, occupant interaction and the possibility of ejection. Crucial post-crash factors in the emergency- and rescue response showed that ordi-nary ways of working and equipment are not always useful and proper equipment for lifting a coach body is essential in the case of a rollover. Finally, the communication between the hospitals is important, and the telephone systems may be overloaded by calls from worried relatives and media.

    Conclusions: In non-crash events: Non-crash events constitute a majority of all bus and coach casualties with a high proportion of elderly female occupants among the MAIS 2+ injury cases. Boarding and, especially alighting causes many injuries to the lower extremities.

    In the pre-crash phase: Cross-winds do affect the safety of buses and coaches and requires more at-tention. Seat belt usage among bus and coach occupants has to be increased.

    In the crash phase: Rollover and ejection are the major causes behind serious and fatal injuries to bus and coach occupants, consequently, retentive glazing, pillars or rails need more attention. An upgrade from 2-point seat belts to 3-point seat belts yields an increase in the estimated injury re-duction from approximately 50% up to 80% for the MAIS 2+ casualties in a rollover crash.

    In the post-crash phase: In order to be able to lift a coach body proper equipment originated from experience and development is essential in a rescue operation of a crashed bus or coach. Fur-thermore, to improve the emergency response inside crashed coaches proper methods originated from experience need to be developed.

    Euro NBAP: Based on the results and conclusions generated in this thesis, a European New Bus and Coach Assessment Programme is suggested, which would provide bus and coach occupants with a assessment programme similar to the Euro NCAP.

  • 55.
    Albertsson, Pontus
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Björnstig, Ulf
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Falkmer, Torbjörn
    The Haddon matrix, a tool for investigating severe bus and coach crashes2003In: International Journal of Disaster Medicine, ISSN 1503-1438, E-ISSN 1755-4713, Vol. 1, no 2, p. 109-119Article in journal (Refereed)
    Abstract [en]

    Objective: The aim of the study was to use the Haddon matrix to analyse crash and injury mechanisms in a severe coach crash, to investigate if a safety belt would have reduced injuries, and highlight the triage problem in a mass casualty situation during severe circumstances. Methods: A specific coach crash was chosen as the subject for the case study. All 34 occupants on board were interviewed about the crash, their injuries, and how they sustained their injuries. Medical records concerning ambulance and hospital treatment have been examined. Police reports and other documents concerning the vehicle, weather conditions and the road have been examined. The materials were structured in different cells according to Haddon's matrix. Results: The coach went off a road via a guard-rail and landed on the right side, in a 90° position right across a small river. The main reason for the coach to deviate from the road was strong and gusty side winds imposing lateral forces on the coach, making steering impossible. The impact from the crash was greatest in the front part of the coach, as this part fell 3 metres from the bridge guard-rail down to the river bank. The most frequent injury mechanism was that occupants were hit by other falling occupants. Most occupants would have benefited from having worn seat belts. Ten ambulances and one helicopter from different locations were called upon and the first ambulance arrived 30 minutes after the alarm (a 67-km drive). The helicopter, with an anaesthetist on board, arrived after 1 hour and 20 minutes (a 120-km flight). Nine occupants with moderate injuries and 10 seriously or severely injured occupants were transported by ambulance or helicopter to the hospital. Fifteen occupants, triaged as priority 3, were transported by a chartered coach to hospital where they arrived after about 3 hours. Conclusion: If 100% of the occupants had used a two-point belt, about two-thirds of the injured occupants with MAIS 2+ injuries would have sustained an injury reduction. A further injury reduction by roughly 20% could have been achieved by shifting from two-point belts to three-point belts. Triage of injured occupants could be different from normal practice because of the limited space inside a coach, and the use of ordinary equipment is not always possible inside a crashed vehicle. The fact that most of the side windows remained in position after the crash probably prevented many occupants from serious and fatal injuries caused by ejection or partial ejection.

  • 56.
    Albertsson, Pontus
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Björnstig, Ulf
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Petzäll, J
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Falkmer, T
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Näsman, Y
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Utrymningsförsök av passagerare ur buss vid brand och brandtillbud samt antalet bränder och brandtillbud i bussar i Sverige.2006In: Scand J Trauma Rescue Emerg Med, Vol. 14, p. 85-91Article in journal (Refereed)
  • 57.
    Albertsson, Pontus
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Falkmer, Torbjörn
    Is there a pattern in European bus and coach incidents?: A literature analysis with special focus on injury causation and injury mechanisms2005In: Accident Analysis and Prevention, ISSN 0001-4575, E-ISSN 1879-2057, Vol. 37, no 2, p. 225-233Article in journal (Refereed)
    Abstract [en]

    In order to identify and describe a pattern in bus and coach incident related injuries and fatalities, and to suggest possible future measures for improvement of bus and coach safety, a literature analysis was performed. The results formed a multi-faceted pattern, which briefly can be described as follows; women travelled more frequently by bus as compared to men. Injuries sustained predominantly affected women 60 years of age and older. Of all traffic fatalities in Europe, bus and coach fatalities represented 0.3-0.5%. In the OECD countries, the risk of being killed or seriously injured was found to be seven to nine times lower for bus and coach occupants as compared to those of car occupants. Despite the fact that fatalities were more frequent on rural roads, a vast majority of all bus and coach casualties occurred on urban roads and in dry weather conditions. Boarding and alighting caused about one-third of all injury cases. Collisions were a major injury-contributing factor. Buses and coaches most frequently collided with cars, but unprotected road users were hit in about one-third of all cases of a collision, the point of impact on the bus or the coach being typically frontal or side. Rollovers occurred in almost all cases of severe coach crashes. In this type of crash projection, total ejection, partial ejection, intrusion and smoke inhalation were the main injury mechanisms and among those, ejection being the most dangerous. A 2-point belt may prevent passenger ejection, but in frontal crashes when the upper abdominal parts and the head hit the seatback in front, it could, however, contribute to head and thoracic injuries. Hence, a 3-point belt provides the best restraint in rollovers and frontal crashes.

  • 58.
    Albertsson, Pontus
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Falkmer, Torbjörn
    Kirk, A
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Mayrhofer, E
    Björnstig, Ulf
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Case study: 128 injured in rollover coach crashes in Sweden - injury outcome, mechanisms and possible effects of seat belts.2006In: Safety Science, ISSN 0925-7535, E-ISSN 1879-1042, Vol. 44, no 2, p. 87-109Article in journal (Refereed)
    Abstract [en]

    The risk for injuries in rollover coach crashes are dependent on whether the occupants are belted or not. However, the influence of the different belt systems for reducing injuries has remained unclear. Since many injuries sustained are caused by impacts with the interior, passenger interactions or ejection through a window, the advantages by proper seat belt systems are evident. In this study, representing the most common serious crash scenario for serious injury, 128 injured in rollover cases were analysed with regard to the injury outcome, mechanisms and the possible injury reduction for occupants when using a safety belt. Furthermore, the different belt systems were compared to explain their contribution to increased safety. Based on medical reports and questioning of the passengers, the injuries sustained are recorded according to the AIS classification. The next step was the identification of the injury mechanisms, using the passenger statements as well as results from numerical occupant simulations. It is important to mention that this study was purely focused on detection of the injury mechanism to avoid the reported injuries. The possibility of additional injuries due to the wearing of a belt were not taken into account. However, the analysis of the 128 injured showed a considerable increase in safety for belted occupants through limiting interior contacts, minimising passenger interaction and reducing the possibility of ejection.

  • 59.
    Albertsson, Pontus
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Sundström, Anna
    Umeå University, Faculty of Social Sciences, Department of applied educational science, Departement of Educational Measurement.
    Evaluation of Insight Training of Ambulance Drivers in Sweden Using DART: a New E-learning Tool2011In: Traffic Injury Prevention, ISSN 1538-9588, E-ISSN 1538-957X, Vol. 12, no 6, p. 621-629Article in journal (Refereed)
    Abstract [en]

    Objective: The aim of the study was to evaluate whether a new e-learning tool for insight training of ambulance drivers can have an effect on drivers’ driving behaviors, perceived driving competence, competence to assess risks, self-reflection, and safety attitudes.

    Methods: A quasi-experimental study design, with participants nonrandomly assigned into a control and intervention group, was used. The intervention group participated in the insight-training course and the control group did not. Both groups completed a self- and peer assessment online questionnaire before and after the training.

    Results: The main finding is that the ambulance drivers assessed themselves through the instruments after the training, with the e-learning tool Driver Access Recording Tool (DART), as safer drivers in the areas of speed adaptation, closing up, and overtaking. In the answers from the group-based evaluation, the ambulance drivers responded that they were more reflective/analytical, had increased their risk awareness, and had changed their driving behaviors.

    Conclusions: After insight training, the ambulance drivers in this study assessed themselves as safer drivers in several important areas, including speed adaptation, closing up, and overtaking. In future training of ambulance drivers there should be more focus on insight training instead of previous training focusing on maneuvering capabilities.

  • 60.
    Albertsson, Sandra
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Juntunen, Martin
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Styrketräningsadaption: Aminosyrafördelning och intracellulär signalering2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Muscle mass regulation is responsive to a variety of stimuli, whereas amino acids and resistance exercise are two major regulators. Protein accretion occurs when the rate of protein synthesis exceeds the rate of protein degradation. It has long been recognized that both amino acid and resistance exercise effect protein synthesis and protein degradation, although the effect of varying distribution of amino acids remain unknown. The intracellular pathways by which protein synthesis are activated is complex. The purpose of this essay is to elucidate if there exist any scientific rationale to spread the amino acid intake over the day, with the purpose to maximize muscle protein accretion in response to resistance exercise. Furthermore , we intend to describe how amino acids and resistance exercise effect the molecular pathways that regulate protein synthesis, with the main focus on pathways that activate and are activated by mTOR.

    Studies that examine acute effects on protein synthesis or protein balance after resistance exercise and amino acid intake support the notion that there may be an advantage to spread the amino acid intake over the day, since the synthetic response to amino acids are transient. However, studies examining the effect of different meal frequencies on protein accretion and /or training results fail to support this notion. Both amino acids and resistance exercise seems to independently activate the intracellular pathways that regulate protein synthesis, with the effect being greatest when both are combined. The regulation also seems to be dependent on exercise intensity and volume, age of test subjects, contraction type and muscle fiber type. Furthermore, some researchers have found correlations between activation of these pathways and resistance exercise-induced muscle gain and strength gain.

  • 61. Albiges, Laurence
    et al.
    Powles, Tom
    Staehlerr, Michael
    Bensalan, Karim
    Giles, Rachel H.
    Horag, Milan
    Kuczyk, Markus A.
    Lam, Thomas B.
    Ljungberg, Börje
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Urology and Andrology.
    Marconi, Lorenzo
    Merseburger, Axel S.
    Volpe, Alessandro
    Abu-Ghanem, Yasmin
    Dabestani, Saeed
    Fernndez-Pello, Sergio
    Hofmann, Fabian
    Kuusk, Teele
    Tahbaz, Rana
    Bex, Axel
    Updated European Association of Urology Guidelines on Renal Cell Carcinoma: Immune Checkpoint Inhibition Is the New Backbone in First-line Treatment of Metastatic Clear-cell Renal Cell Carcinoma2019In: European Urology, ISSN 0302-2838, E-ISSN 1873-7560, Vol. 76, no 2, p. 151-156Article in journal (Refereed)
    Abstract [en]

    Recent randomised trials have demonstrated a survival benefit for a front-line ipilimumab and nivolumab combination therapy, and pembrolizumab and axitinib combination therapy in metastatic clear-cell renal cell carcinoma. The European Association of Urology Guidelines Panel has updated its recommendations based on these studies.

    Patient summary: Pembrolizumab plus axitinib is a new standard of care for patients diagnosed with kidney cancer spread outside the kidney and who did not receive any prior treatment for their cancer (treatment naive). This applies to all risk groups as determined by the International Metastatic Renal Cell Carcinoma Database Consortium criteria.

  • 62. Aleksandrova, Krasimira
    et al.
    Bamia, Christina
    Drogan, Dagmar
    Lagiou, Pagona
    Trichopoulou, Antonia
    Jenab, Mazda
    Fedirko, Veronika
    Romieu, Isabelle
    Bueno-de-Mesquita, H. Bas
    Pischon, Tobias
    Tsilidis, Kostas
    Overvad, Kim
    Tjønneland, Anne
    Bouton-Ruault, Marie-Christine
    Dossus, Laure
    Racine, Antoine
    Kaaks, Rudolf
    Kuehn, Tilman
    Tsironis, Christos
    Papatesta, Eleni-Maria
    Saitakis, George
    Palli, Domenico
    Panico, Salvatore
    Grioni, Sara
    Tumino, Rosario
    Vineis, Paolo
    Peeters, Petra H.
    Weiderpass, Elisabete
    Lukic, Marko
    Braaten, Tonje
    Ramon Quiros, J.
    Lujan-Barroso, Leila
    Sanchez, Mara-Jose
    Chilarque, Maria-Dolores
    Ardanas, Eva
    Dorronsoro, Miren
    Nilsson, Lena Maria
    Umeå University, Arctic Research Centre at Umeå University.
    Sund, Malin
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Nutritional Research.
    Wallström, Peter
    Ohlsson, Bodil
    Bradbury, Kathryn E.
    Khaw, Kay-Tee
    Wareham, Nick
    Stepien, Magdalena
    Duarte-Salles, Talita
    Assi, Nada
    Murphy, Neil
    Gunter, Marc J.
    Riboli, Elio
    Boeing, Heiner
    Trichopoulos, Dimitrios
    The association of coffee intake with liver cancer risk is mediated by biomarkers of inflammation and hepatocellular injury: data from the European Prospective Investigation into Cancer and Nutrition2015In: American Journal of Clinical Nutrition, ISSN 0002-9165, E-ISSN 1938-3207, Vol. 102, no 6, p. 1498-1508Article in journal (Refereed)
    Abstract [en]

    Background: Higher coffee intake has been purportedly related to a lower risk of liver cancer. However, it remains unclear whether this association may be accounted for by specific biological mechanisms. Objective: We aimed to evaluate the potential mediating roles of inflammatory, metabolic, liver injury, and iron metabolism biomarkers on the association between coffee intake and the primary form of liver cancer-hepatocellular carcinoma (HCC). Design: We conducted a prospective nested case-control study within the European Prospective Investigation into Cancer and Nutrition among 125 incident HCC cases matched to 250 controls using an incidence-density sampling procedure. The association of coffee intake with HCC risk was evaluated by using multivariable-adjusted conditional logistic regression that accounted for smoking, alcohol consumption, hepatitis infection, and other established liver cancer risk factors. The mediating effects of 21 biomarkers were evaluated on the basis of percentage changes and associated 95% CIs in the estimated regression coefficients of models with and without adjustment for biomarkers individually and in combination. Results: The multivariable-adjusted RR of having >= 4 cups (600mL) coffee/d compared with <2 cups (300 mL)/d was 0.25 (95% CI: 0.11, 0.62; P-trend = 0.006). A statistically significant attenuation of the association between coffee intake and HCC risk and thereby suspected mediation was confirmed for the inflammatory biomarker IL-6 and for the biomarkers of hepatocellular injury glutamate dehydrogenase, alanine aminotransferase, aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), and total bilirubin, which-in combination-attenuated the regression coefficients by 72% (95% CI: 7%, 239%). Of the investigated biomarkers, IL-6, AST, and GGT produced the highest change in the regression coefficients: 40%, 56%, and 60%, respectively. Conclusion: These data suggest that the inverse association of coffee intake with HCC risk was partly accounted for by biomarkers of inflammation and hepatocellular injury.

  • 63. Aleksandrova, Krasimira
    et al.
    Boeing, Heiner
    Nöthlings, Ute
    Jenab, Mazda
    Fedirko, Veronika
    Kaaks, Rudolf
    Lukanova-McGregor, Annekatrin
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology. Division of Cancer Epidemiology, German Cancer Research Center, Heidelberg, Germany.
    Trichopoulou, Antonia
    Trichopoulos, Dimitrios
    Boffetta, Paolo
    Trepo, Elisabeth
    Westhpal, Sabine
    Duarte-Salles, Talita
    Stepien, Magdalena
    Overvad, Kim
    Tjønneland, Anne
    Halkjær, Jytte
    Boutron-Ruault, Marie-Christine
    Dossus, Laure
    Racine, Antoine
    Lagiou, Pagona
    Bamia, Christina
    Benetou, Vassiliki
    Agnoli, Claudia
    Palli, Domenico
    Panico, Salvatore
    Tumino, Rosario
    Vineis, Paolo
    Bueno-de-Mesquita, Bas
    Peeters, Petra H
    Gram, Inger Torhild
    Lund, Eiliv
    Weiderpass, Elisabete
    Quirós, J Ramón
    Agudo, Antonio
    Sánchez, María-José
    Gavrila, Diana
    Barricarte, Aurelio
    Dorronsoro, Miren
    Ohlsson, Bodil
    Lindkvist, Björn
    Johansson, Anders
    Umeå University, Faculty of Medicine, Department of Odontology. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Nutritional Research.
    Sund, Malin
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Khaw, Kay-Tee
    Wareham, Nicholas
    Travis, Ruth C
    Riboli, Elio
    Pischon, Tobias
    Inflammatory and metabolic biomarkers and risk of liver and bilary tract cancer2014In: Hepatology, ISSN 0270-9139, E-ISSN 1527-3350, Vol. 60, no 3, p. 858-871Article in journal (Refereed)
    Abstract [en]

    Obesity and associated metabolic disorders have been implicated in liver carcinogenesis; however there is little data on the role of obesity-related biomarkers on liver cancer risk. We studied prospectively the association of inflammatory and metabolic biomarkers with risks of hepatocellular carcinoma (HCC), intra-hepatic bile duct (IBD) and gallbladder and bilary tract cancers outside of the liver (GBTC) in a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC). Over an average of 7.7 years, 296 participants developed HCC (n=125), GBTC (n=137) or IBD (n=34). Using risk set sampling, controls were selected in a 2:1 ratio and matched for recruitment center, age, sex, fasting status, time of blood collection. Baseline serum concentrations of C-reactive protein (CRP), interleukin-6 (IL-6), C-peptide, total, high-molecular-weight (HMW) adiponectin, leptin, fetuin-a, and glutamatdehydrogenase (GLDH) were measured and incidence rate ratios (IRRs) and 95% confidence intervals (CI-s) estimated using conditional logistic regression. After adjustment for lifestyle factors, diabetes, hepatitis infection and adiposity measures, higher concentrations of CRP, IL-6, C-peptide and non-HMW adiponectin were associated with higher risk of HCC (IRR per doubling of concentrations = 1.22; 95%CI = 1.02-1.46, P=0.03; 1.90; 95%CI = 1.30-2.77, P=0.001; 2.25; 95%CI = 1.43-3.54, P=0.0005 and 2.09; 95%CI = 1.19-3.67, P=0.01, respectively). CRP was associated also with risk of GBTC (IRR = 1.22; 95%CI = 1.05-1.42, P=0.01). GLDH was associated with risks of HCC (IRR = 1.62; 95%CI = 1.25-2.11, P=0.0003) and IBD (IRR = 10.5; 95%CI = 2.20-50.90, P=0.003). The continuous net reclassification index was 0.63 for CRP, IL-6, C-peptide and non-HMW adiponectin, and 0.46 for GLDH indicating good predictive ability of these biomarkers. Conclusion: Elevated levels of biomarkers of inflammation and hyperinsulinemia are associated with a higher risk of HCC, independent of obesity and established liver cancer risk factors.

  • 64.
    Alenius Dahlqvist, Jenny
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Karlsson, Marcus
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Hörnsten, Rolf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Handheld ECG in analysis of arrhythmia and heart rate variability in children with Fontan circulation2014In: Journal of Electrocardiology, ISSN 0022-0736, E-ISSN 1532-8430, Vol. 47, no 3, p. 374-382Article in journal (Refereed)
    Abstract [en]

    Background: Our aim was to evaluate the intermittent use of a handheld ECG system for detecting silent arrhythmias and cardiac autonomic dysfunction in children with univentricular hearts. Methods: Twenty-seven patients performed intermittent ECG recordings with handheld devices during a 14-day period. A manual arrhythmia analysis was performed. We analyzed heart rate variability (HRV) using scatter plots of all interbeat intervals (Poincare plots) from the total observation period. Reference values of HRV indices were determined from Holter-ECGs in 41 healthy children. Results: One asymptomatic patient had frequent ventricular extra systoles. Another patient had episodes with supraventricular tachycardia (with concomitant palpitations). Seven patients showed reduced HRV. Conclusions: Asymptomatic arrhythmia was detected in one patient. The proposed method for pooling of intermittent recordings from handheld or similar devices may be used for detection of arrhythmias as well as for cardiac autonomic dysfunction.

  • 65.
    Alenius Dahlqvist, Jenny
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Karlsson, Marcus
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Hörnsten, Rolf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Strömvall-Larsson, Eva
    Division of Cardiology, Department of Paediatrics, Sahlgrenska University Hospital/Queen Silvia Children’s Hospital, Göteborg University, Göteborg, Sweden.
    Berggren, Håkan
    Division of Cardiothoracic Surgery, Department of Paediatrics, Sahlgrenska University Hospital/Queen Silvia Children’s Hospital, Göteborg University, Göteborg, Sweden.
    Hanseus, Katarina
    Department of Paediatrics, Children’s Hospital, Lund University Hospital, Lund, Sweden.
    Johansson, Sune
    Paediatric Cardiac Surgical Unit, Children’s Hospital, Lund University Hospital, Lund, Sweden.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Heart rate variability in children with fontan circulation: lateral tunnel and extracardiac conduit2012In: Pediatric Cardiology, ISSN 0172-0643, E-ISSN 1432-1971, Vol. 33, no 2, p. 307-315Article in journal (Refereed)
    Abstract [en]

    The technique in Fontan surgery has developed from the lateral tunnel (LT) toward the extracardiac conduit (EC) used to reduce long-term complications such as atrial arrhythmia and sinus node dysfunction. Heart rate variability (HRV) examines cardiac nervous activity controlling the sinus node. This study aimed to investigate HRV in a cohort of children with univentricular hearts, focusing on the relation between HRV and surgical procedure. For 112 children with Fontan circulation, HRV was analyzed using power spectral analysis. Spectral power was determined in three regions: very-low-frequency (VLF), low-frequency (LF), and high-frequency (HF) regions. Patients were compared with 66 healthy controls subject. Patients with LT were compared with patients who had EC. The children with Fontan circulation showed a significantly reduced HRV including total power (P < 0.0001), VLF (P < 0.0001), LF (P < 0.0001), and HF (P = 0.001) compared with the control subjects. The LT and EC patients did not differ significantly. Reduced HRV was found in both the LT and EC patients. In terms of HRV reduction, EC was not superior to LT.

  • 66.
    Alfraeus, Simon
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Hypotensive Effect of Anesthesia with Target controlled infusion: A randomized controlled trial2016Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 67.
    Alfredson, H.
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Öhberg, L.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Forsgren, Sture
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    Is vasculo-neural ingrowth the cause of pain in chronic Achilles tendinosis?: An investigation using US and colour Doppler, immunohistochemistry, and diagnostic injections2003In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, Vol. 11, no 5, p. 334-338Article in journal (Refereed)
  • 68.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Can specific treatment prevent progressive tendon degeneration?2011In: British Journal of Sports Medicine, ISSN 0306-3674, E-ISSN 1473-0480, Vol. 45, no 4, p. 334-Article in journal (Refereed)
    Abstract [en]

    Background Tendon degeneration is generally believed to be irreversible.

    Objective To use ultrasound to study the Achilles midportion tendon structure and thickness before and after treatment of chronic painful tendinosis.

    Design Prospective study.

    Patients and interventions Middle aged patients on varying activity levels, having midportion chronic Achilles tendinosis, were followed with ultrasound examinations before and after treatment with eccentric training, sclerosing polidocanol injections and surgical scraping.

    Outcome measurements Tendon thickness and structure.

    Results 89 patients successfully treated (pain-free during tendon loading) with eccentric training (n=22), sclerosing polidocanol injections (n=38) and surgical scraping (n=29), had a significantly thinner Achilles midportion and a more normal tendon structure, after compared to before, treatment.

    Conclusion For the Achilles midportion, tendon degeneration might not be irreversible. The findings indicate a possible regeneration potential.

  • 69.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Chronic tendon pain--implications for treatment: an update.2004In: Curr Drug Targets, ISSN 1389-4501, Vol. 5, no 5, p. 407-10Article in journal (Refereed)
  • 70.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Conservative management of Achilles tendinopathy: new ideas.2005In: Foot and ankle clinics of North America, ISSN 1083-7515, Vol. 10, no 2, p. 321-329Article, review/survey (Refereed)
    Abstract [en]

    Chronic Achilles tendinopathy is difficult to treat, and results, even after surgical management, are variable. The few studies that reported long-term results indicated a poor outcome. Also, surgery requires prolonged rehabilitation, and, depending on the patient's occupation, a varying period of sick leave from work. This article gives an update on recently developed conservative treatment methods for the management of chronic Achilles tendinopathy.

  • 71.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Eccentric calf muscle training: the story2010In: Sportverletzung, Sportschaden, ISSN 0932-0555, E-ISSN 1439-1236, Vol. 24, no 4, p. 188-189Article in journal (Refereed)
  • 72.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Midportion Achilles tendinosis and the plantaris tendon2011In: British Journal of Sports Medicine, ISSN 0306-3674, E-ISSN 1473-0480, Vol. 45, no 13, p. 1023-1025Article in journal (Refereed)
    Abstract [en]

    Objectives: When re-operating patients with midportion Achilles tendinosis, having had a poor effect of ultrasound (US) and Doppler-guided scraping, the author found the involvement of the plantaris tendon to be a likely reason for the poor result. The aim of this study was to investigate the occurrence of a plantaris tendon in close relation to the Achilles tendon in consecutive patients with midportion Achilles tendinosis undergoing treatment with US and Doppler-guided scraping.

    Material and methods: This study includes 73 consecutive tendons with chronic painful midportion Achilles tendinosis, where US+Doppler examination showed thickening, irregular tendon structure, hypo-echoic regions, and localised high blood flow outside and inside the ventral Achilles midportion. The tendons were treated with US+Doppler-guided scraping, via a medial incision. If there was a plantaris tendon located in close relation to the medial Achilles, it was extirpated.

    Results: An invaginated, or ‘close by located’, enlarged plantaris tendon was found in 58 of 73 (80%) tendons. Preliminary clinical results of the combined procedure, US + Doppler-guided surgical scraping and extirpation of the plantaris tendon, are very promising.

    Conclusions: A thickened plantaris tendon located in close relation to the medial Achilles seems common in patients with chronic painful midportion tendinosis. The role of the plantaris tendon in midportion Achilles tendinosis needs to be further evaluated and should be kept in mind when treating this condition.

  • 73.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Preliminary results of colour Doppler-guided intratendinous glucocorticoid injection for Achilles tendonitis in five patients.2004In: Scand J Med Sci Sports, ISSN 0905-7188, Vol. 14, no 4, p. 269-70; author reply 270Article in journal (Refereed)
  • 74.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Regenerative injection therapy for chronic painful tendinosis with polidocanol and ultrasound/Doppler guidance2007In: Pain clinic (Print), ISSN 0169-1112, E-ISSN 1568-5691, Vol. 19, no 6, p. 271-276(6)Article in journal (Refereed)
  • 75.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. National Institute for Working Life, University of Umeå , 901 87, Umeå, Sweden .
    Strategies in treatment of tendon overuse injury. The chronic painful tendon.2006In: European Journal of Sport Science, ISSN 1746-1391, E-ISSN 1536-7290, Vol. 6, no 2, p. 81-85Article in journal (Refereed)
    Abstract [en]

    The etiology and pathogenesis to chronic tendon pain is unknown, and treatment is known to be difficult. Treatment is often based on opinions and not findings in scientific studies. Recent research, using the intra-tendinous microdialysis technique, has shown that in chronic painful Achilles-, patellar-, and extensor carpi radialis brevis (ECRB) tendons, there were no signs (normal Prostaglandin-2 levels) of a so-called chemical inflammation. Furthermore, in biopsies from chronic painful Achilles tendons, pro-inflammatory cytokines were not up-regulated, again showing the absence of an intra-tendinous inflammation. Consequently, if the purpose is to treat a chemical inflammation, there is no science backing up for treatment of theses conditions with anti-inflammatory agents (NSAIDs, corticosteroidal injections). Interestingly, Substance-P (SP) and Calcitonin Gene Regulated Peptide (CGRP) nerves have been demonstrated in close relation to vessels in biopsies from these chronic painful tendons, indicating the existence of a possible so-called neurogenic inflammation. Using ultrasonography (US) + color Doppler (CD), and immunhistochemical analyses of biopsies, a vasculo/neural (SP- and CGRP-nerves) ingrowth in the chronic painful tendinosis tendon, but not in the pain-free normal tendon, has recently been found. A specially designed treatment, using US- and CD-guided injections of the sclerosing agent Polidocanol, targeting the neovessels outside the tendon, has in pilot studies on chronic painful Achilles-, and patellar tendons been shown to cure the tendon pain in the majority of patients. A recent randomized double-blind study, verified the importance of injecting the sclerosing substance Polidocanol.

  • 76.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    The chronic painful Achilles and patellar tendon: research on basic biology and treatment.2005In: Scand J Med Sci Sports, ISSN 0905-7188, Vol. 15, no 4, p. 252-9Article in journal (Refereed)
  • 77.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Ultrasound and Doppler-guided mini-surgery to treat midportion Achilles tendinosis: results of a large material and a randomised study comparing two scraping techniques.2011In: British Journal of Sports Medicine, ISSN 0306-3674, E-ISSN 1473-0480, Vol. 45, no 5, p. 407-410Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Treatment based on ultrasound (US) and colour Doppler (CD) findings in midportion Achilles tendinosis has shown promising results. In a randomised study on a small patient material, similar short-term clinical results were demonstrated with surgery outside the tendon and sclerosing polidocanol injections, but surgical treatment led to a faster return to activity.

    OBJECTIVE: To evaluate the clinical results of US and CD-guided mini-surgery (scraping) outside the ventral tendon in a larger patient material and, in a randomised study, compare two different techniques for surgical scraping.

    MATERIAL AND METHODS: 103 patients (66 men, 37 women), mean age 43 years (range 24-77), with midportion tendinosis in 125 Achilles tendons were included. Patients from a large group (88 tendons), and a randomised study (37 tendons), were in local anaesthesia treated with a US and CD-guided new surgical approach outside the ventral tendon. All patients in the large group, and one arm of the randomised study, were treated open with a scalpel, while the other arm of the randomised study were treated percutaneously. Pain during Achilles tendon loading activity (Visual Analogue Scale (VAS)), and satisfaction with treatment, were evaluated.

    RESULTS: Before surgery, the mean VAS was 73. After surgery (follow-up mean 18 months, range 6-33), the mean VAS was 3 in 111 tendons (89%) from satisfied patients back in full Achilles tendon loading activity. In the randomised study, there were no significant differences in the results between open treatment with a scalpel and percutaneous treatment with a needle.

    CONCLUSIONS: US and CD-guided scraping show good short-term results in midportion Achilles tendinosis.

  • 78.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Where to now with Achilles tendon treatment?2011In: British Journal of Sports Medicine, ISSN 0306-3674, E-ISSN 1473-0480, Vol. 45, no 5, p. 386-386Article in journal (Refereed)
  • 79.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Bjur, Dennis
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Thorsen, Kim
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Sandström, Patrick
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    High intratendinous lactate levels in painful chronic Achilles tendinosis. An investigation using microdialysis technique.2002In: Journal of Orthopaedic Research, ISSN 0736-0266, E-ISSN 1554-527X, Vol. 20, no 5, p. 934-938Article in journal (Refereed)
    Abstract [en]

    In this investigation the microdialysis technique was used to study the concentrations of lactate in Achilles tendons with painful chronic tendinosis and in normal pain-free tendons. In four patients (mean age 40.7 years) with a painful thickening localized at the 2-6 cm level in the Achilles tendon (chronic Achilles tendinosis) and in five controls (mean age 37.2 years) with normal Achilles tendons the local concentrations of lactate were registered under resting conditions. All tendons were examined using ultrasonography. In the tendons with tendinosis the painful thickening corresponded to a widened tendon and structural tendinosis changes. Normal tendons showed no widening and a normal structure. A standard microdialysis catheter was inserted into the Achilles tendon under local anesthesia. Samplings were done every 15 min during a 4 h period. The results showed significantly higher mean concentrations of lactate in tendons with tendinosis compared to normal tendons (2.15 mmol/l vs. 1.14 mmol/l). The lactate concentrations in the tendons with tendinosis were stable, and approximately twofold higher than in the normal tendons during the whole 4 h investigation period. In conclusion, the higher concentrations of lactate in Achilles tendons with painful tendinosis indicate that there are anaerobic conditions in the area with tendinosis. The importance of this finding for the pathogenesis and pain mechanisms in this chronic condition needs to be further investigated.

  • 80.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Cook, J
    A treatment algorithm for managing Achilles tendinopathy: new treatment options.2007In: British Journal of Sports Medicine, ISSN 0306-3674, E-ISSN 1473-0480, Vol. 41, no 4, p. 211-216Article, review/survey (Refereed)
    Abstract [en]

    Achilles tendinopathy affects athletes, recreational exercisers and even inactive people. The pathology is not inflammatory; it is a failed healing response. The source of pain in tendinopathy could be related to the neurovascular ingrowth seen in the tendon's response to injury. The treatment of Achilles tendinopathy is primarily conservative with an array of effective treatment options now available to the primary care practitioner. If conservative treatment is not successful, then surgery relieves pain in the majority of cases. Directing a patient through the algorithm presented here will maximise positive treatment outcomes.

  • 81.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Forsgren, Sture
    Umeå University, Faculty of Medicine, Integrative Medical Biology, Anatomy.
    Thorsen, Kim
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Fahlström, Martin
    Umeå University, Faculty of Medicine, Community Medicine and Rehabilitation, Rehabilitation Medicine. Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Johansson, Håkan
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Glutamate NMDAR1 receptors localised to nerves in human Achilles tendons. Implications for treatment?2001In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 9, no 2, p. 123-126Article in journal (Refereed)
    Abstract [en]

    In this investigation, we show the presence of both free glutamate (microdialysis) and glutamate NMDAR1 receptors (immunohistochemical analyses of tendon biopsies), in tendons from patients with chronic Achilles tendon pain (Achilles tendinosis) and in controls (pain-free tendons). The NMDAR1 immunoreaction was usually confined to acetylcholinesterase-positive structures, implying that the reaction is present in nerves. Glutamate is a potent pain mediator in the human central nervous system, and in animals it has been shown that peripherally administered glutamate NMDA receptor antagonists diminish the response to formalin-induced nociception. Our present finding of glutamate NMDA receptors in human Achilles tendons might have implications for pain treatment.

  • 82.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Forsgren, Sture
    Umeå University, Faculty of Medicine, Integrative Medical Biology, Anatomy.
    Thorsen, Kim
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    In vivo microdialysis and immunohistochemical analyses of tendon tissue demonstrated high amounts of free glutamate and glutamate NMDAR1 receptors, but no signs of inflammation, in Jumper's knee.2001In: Journal of Orthopaedic Research, ISSN 0736-0266, E-ISSN 1554-527X, Vol. 19, no 5, p. 881-886Article in journal (Refereed)
    Abstract [en]

    This investigation describes, to our knowledge, the first experiment where the microdialysis technique was used to study certain metabolic events in human patellar tendons in combination with immunohistochemical analyses of tendon biopsies. In five patients (four men and one woman) with a long duration (range 12-36 months) of pain symptoms from Jumper's knee (localized tenderness in the patellar tendon verified as tendon changes with ultrasonography or MRI), and in five controls (four men and one woman) with normal patellar tendons, a standard microdialysis catheter was inserted into the patellar tendon under local anestesia. The local concentrations of glutamate (excitatory neurotransmitter) and prostaglandin E2 (PGE2) were registered under resting conditions. Samplings were done every 15 min during a 2 h period. In all individuals (patients and controls) biopsies were taken for immunohistochemical analyses. The results showed that it was possible to detect and measure the concentrations of glutamate and PGE2 in the patellar tendon with the use of microdialysis technique. There were significantly higher concentrations of free glutamate, but not PGE2, in tendons with tendinosis compared to normal tendons. In the biopsies, there were no inflammatory cell infiltrates, but, for the first time, it was shown that there was immunoreaction for the glutamate receptor NMDAR1 in association with nerve structures in human patellar tendons. These findings altogether indicate that glutamate might be involved in painful Jumper's knee, and further emphasizes that there is no chemical inflammation (normal PGE2 levels) in this chronic condition.

  • 83.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Harstad, Herlof
    Haugen, Simen
    Ohberg, Lars
    Umeå University, Faculty of Medicine, Radiation Sciences, Diagnostic Radiology.
    Sclerosing polidocanol injections to treat chronic painful shoulder impingement syndrome-results of a two-centre collaborative pilot study.2006In: Knee Surg Sports Traumatol Arthrosc, ISSN 0942-2056, Vol. 14, no 12, p. 1321-6Article in journal (Refereed)
  • 84.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Hedberg, G
    Bergström, E
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    High thigh muscle strength but not bone mass in young horseback-riding females1998In: Calcified Tissue International, ISSN 0171-967X, E-ISSN 1432-0827, Vol. 62, no 6, p. 497-501Article in journal (Refereed)
    Abstract [en]

    To evaluate whether the type of weight-bearing loading subjected to the skeleton during horseback-riding was associated with differences in bone mass and muscle strength of the thigh, we investigated bone mass and isokinetic muscle strength in 20 female horse riders (age 17.9 +/- 0.6 years) who were riding 7.0 +/- 3.4 hours/week, and 20 nonactive females (age 17.8 +/- 1.1 years). The groups were matched according to age, weight, and height. Areal bone mineral density was measured in total body, head, lumbar spine, right femoral neck, Ward's triangle, and trochanter, the whole dominant and nondominant humerus, and in specific sites in the right femur diaphysis, distal femur, proximal tibia, and tibia diaphysis using dual X-ray absorptiometry. Isokinetic concentric and eccentric peak torque of the quadricep and hamstring muscles were measured using an isokinetic dynamometer. There were no significant differences in bone mass between the horseback riders and nonactives at any site measured. The horse riders were significantly (P < 0.05-0.01) stronger in concentric hamstrings strength at 90 degrees/second and 225 degrees/second and in eccentric quadricep and hamstring strength at 90 degrees/second. Horseback riding in young females is associated with a high muscle strength of the thigh, but not with a high bone mass.

  • 85.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Ljung, B O
    Thorsen, Kim
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    In vivo investigation of ECRB tendons with microdialysis technique--no signs of inflammation but high amounts of glutamate in tennis elbow.2000In: Acta Orthopaedica Scandinavica, ISSN 0001-6470, Vol. 71, no 5, p. 475-479Article in journal (Refereed)
    Abstract [en]

    We used the microdialysis technique to study concentrations of substances in the extensor carpi radialis brevis (ECRB) tendon in patients with tennis elbow. In 4 patients (mean age 41 years, 3 men) with a long duration of localized pain at the ECRB muscle origin, and in 4 controls (mean age 36 years, 2 men) with no history of elbow pain, a standard microdialysis catheter was inserted into the ECRB tendon under local anesthesia. The local concentrations of the neurotransmitter glutamate and prostaglandin E2 (PGE2) were recorded under resting conditions. Samplings were done every 15 minutes during a 2-hour period. We found higher mean concentrations of glutamate in ECRB tendons from patients with tennis elbow than in tendons from controls (215 vs. 69 micromoL/L, p < 0.001). There were no significant differences in the mean concentrations of PGE2 (74 vs. 86 pg/mL). In conclusion, in situ microdialysis can be used to study certain metabolic events in the ECRB tendon of the elbow. Our findings indicate involvement of the excitatory neurotransmitter glutamate, but no biochemical signs of inflammation (normal PGE2 levels) in ECRB tendons from patients with tennis elbow.

  • 86.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Mattias
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Bäckman, Stina
    Umeå University, Faculty of Medicine, Department of Odontology, Oral Cell Biology.
    Bäckman, Assar
    Umeå University, Faculty of Medicine, Department of Odontology, Oral Cell Biology.
    Lerner, Ulf H
    Umeå University, Faculty of Medicine, Department of Odontology, Oral Cell Biology.
    cDNA-arrays and real-time quantitative PCR techniques in the investigation of chronic Achilles tendinosis.2003In: Journal of Orthopaedic Research, ISSN 0736-0266, E-ISSN 1554-527X, Vol. 21, no 6, p. 970-975Article in journal (Refereed)
    Abstract [en]

    The aetiology and pathogenesis of chronic painful Achilles tendinosis are unknown. This investigation aimed to use cDNA arrays and real-time quantitative polymerase chain reaction (real-time PCR) technique to study tendinosis and control tissue samples. Five patients (females mean age 57.1+/-4.3 (years+/-SD)) with chronic painful Achilles tendinosis were included. From all patients, one biopsy was taken from the area with tendinosis and one from a clinically normal area (control) of the tendon. The tissue samples were immediately immersed in RNAlater and frozen at -80 degrees C until RNA extraction. Portions of pooled RNA from control and tendinosis sites, respectively, were transcribed to cDNA, radioactively labelled (32P), hybridized to cDNA expression arrays, and exposed to phosphoimager screens over night. Expressions of specific genes, shown to be regulated in the cDNA array analysis, were analyzed in the individual samples using real-time PCR. cDNA arrays showed that gene expressions for matrix-metalloproteinase-2 (MMP-2), fibronectin subunit B (FNRB), vascular endothelial growth factor (VEGF), and mitogen-activated protein kinase p38 (MAPKp38) were up-regulated, while matrix-metalloproteinase-3 (MMP-3) and decorin were down-regulated, in tendinosis tissue compared with control tissue. Using real-time PCR, 4/5 and 3/5 patients showed up-regulation of MMP-2 and FNRB mRNA, respectively. For decorin, VEGF, and MAPKp38, real-time PCR revealed a great variability among patients. Interestingly, the mRNAs for several cytokines and cytokine receptors were not regulated, indicating the absence of an inflammatory process in chronic painful Achilles tendinosis. In conclusion, cDNA-arrays and real-time PCR can be used to study differences in gene expression levels between tendinosis and control tendon tissue.

  • 87.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, R
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Autologous periosteum transplantation for the treatment of full thickness patellar cartilage defects.2001In: Ortopedia, traumatologia, rehabilitacja, ISSN 1509-3492, Vol. 3, no 2, p. 216-223Article in journal (Refereed)
    Abstract [en]

    Full-thickness patellar cartilage defects are often, but not always, associated with disabling anterior knee-pain and inability to take part in regular daily activities. There is no treatment of choice for this condition. It is well known that the cells in the cambium layer of the periosteum are pluripotent and can differentiate into hyaline (or hyaline-like) cartilage, especially if in a joint environment and under the influence of continous passive motion. In a few clinical studies autologous periosteum transplants alone have been used in the treatment of full thickness patellar cartilage defects. The results are varying. At our clinic, autologous periosteum transplantation alone, followed by continous passive motion (CPM) in the immediate postoperative period and non-weight bearing loading for 3 months, has shown promising clinical results. The best clinical results have been achieved on traumatic (fracture, contusion, dislocation) cartilage defects, where 83% of patients have been clinically graded as excellent or good at follow-up (> 2 years postoperatively). For non-traumatic patellar cartilage defects (chondromalacia NUD) the results are poor, with only 35% of patients being graded as excellent or good. Therefore, we believe that no-traumatic patellar cartilage defects (chondromalacia NUD) are less suitable for treatment with autologous periosteum transplants, and are at our clinic not any longer included for this type of treatment.

  • 88.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Chronic Achilles tendinosis: recommendations for treatment and prevention.2000In: Sports Medicine, ISSN 0112-1642, E-ISSN 1179-2035, Vol. 29, no 2, p. 135-146Article in journal (Refereed)
    Abstract [en]

    Chronic Achilles tendinosis is a condition with an unknown aetiology and pathogenesis that is often, but not always, associated with pain during loading of the Achilles tendon. Histologically, there are no inflammatory cells, but increased amounts of interfibrillar glycosaminoglycans and changes in the collagen fibre structure and arrangement are seen. In situ microdialysis has confirmed the absence of inflammation. It is a condition that is most often seen among recreational male runners aged between 35 and 45 years, and it is most often considered to be associated with overuse. However, this condition is also seen in patients with a sedentary lifestyle. Chronic Achilles tendinosis is considered a troublesome injury to treat. Nonsurgical treatment most often includes a combination of rest, NSAIDs, correction of malalignments, and stretching and strengthening exercises, but there is sparse scientific evidence supporting the use of most proposed treatment regimens. It has been stated that, in general, nonsurgical treatment is not successful and surgical treatment is required in about 25% of patients. However, in a recent prospective study, treatment with heavy load eccentric calf muscle training showed very promising results and may possibly reduce the need for surgical treatment of tendinosis located in the midportion of the Achilles tendon. The short term results after surgical treatment are frequently very good, but in the few studies with long term follow-up there are signs of a possible deterioration with time. Calf muscle strength takes a long time to recover and, furthermore, a prolonged progressive calcaneal bone loss has been shown on the operated side up to 1 year after surgical treatment.

  • 89.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Intratendinous glutamate levels and eccentric training in chronic Achilles tendinosis: a prospective study using microdialysis technique.2003In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 11, no 3, p. 196-199Article in journal (Refereed)
    Abstract [en]

    Microdialysis has shown intratendinous glutamate levels to be significantly higher in Achilles tendons with painful tendinosis than in normal pain-free tendons, and treatment with eccentric training has shown good clinical results with diminished tendon pain during activity. In six patients with chronic painful Achilles tendinosis we performed microdialysis for 2 h, before and after the 12-week eccentric training program. The treatment was successful in all six patients, and the mean VAS score (amount of pain during Achilles tendon loading) decreased from 69 before treatment to 17 after treatment. There was no significant difference between the intratendinous glutamate levels before and after treatment. Our results offer no obvious neurophysiological explanation but showed that successful treatment with eccentric training was not associated with lowered intratendinous glutamate levels.

  • 90.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Sclerosing polidocanol injections of small vessels to treat the chronic painful tendon.2007In: Cardiovascular & hematological agents in medicinal chemistry, ISSN 1871-5257, Vol. 5, no 2, p. 97-100Article, review/survey (Refereed)
    Abstract [en]

    The chronic painful tendon (tendinopathy, tendinosis) is generally considered difficult to treat, not seldom causing long-term disability and sometimes ending the sports or work carreér. Most common sites for tendinopathy are the Achilles-, patellar-, extensor carpi radialis brevis (ERCB)-, and supraspinatus tendons. The origin of pain has for many years been unknown, but recently, by using ultrasound (US) + colour Doppler (CD), immunohistochemical analyses of tendon biopsies, and diagnostic injections of local anaestesia, we found a close relationship between areas with vasculo-neural ingrowth and tendon pain. Sensory nerves (Substance-P-SP and Calcitonin Gene Related Peptide-CGRP) were found inside and outside the vascular wall. In following clinical studies we have demonstrated good short-and mid-term clinical results using treatment with US+CD-guided sclerosing polidocanol injections, targeting the area with neovessels outside the tendon. Two-year follow ups have showed remaining good clinical results, and sonographically signs of remodelling with a significantly thinner tendon with a more normal structure. Whether the effects of polidocanol are mediated through destruction of neovessels, activity on nerves or a combination, is under evaluation.

  • 91.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Superior results with continuous passive motion compared to active motion after periosteal transplantation: A retrospective study of human patella cartilage defect treatment1999In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 7, no 4, p. 232-238Article in journal (Refereed)
    Abstract [en]

    Fifty-seven consecutive patients (33 men and 24 women), with a mean age of 32 years (range 16-53 years), who suffered from an isolated full-thickness cartilage defect of the patella and disabling knee pain of long duration, were treated by autologous periosteal transplantation to the cartilage defect. The first 38 consecutive patients (group A) were postoperatively treated with continuous passive motion (CPM), and the next 19 consecutive patients (group B) were treated with active motion for the first 5 days postoperatively. In both groups, the initial regimens were followed by active motion, slowly progressive strength training, and slowly progressive weight bearing. In group A, after a mean follow-up of 51 months (range 33-92 months), 29 patients (76%) were graded as excellent or good, 7 patients (19%) were graded as fair, and 2 patients (5%) were graded as poor. In group B, after a mean follow-up of 21 months (range 14-28 months), 10 patients (53%) were graded as excellent or good, 6 patients (32%) were graded as fair, and 3 patients (15%) were graded as poor. Altogether, nine of the fair or poor cases (50%) were diagnosed with chondromalacia of the patella. Our results, after performing autologous periosteal transplantation in patients with full-thickness cartilage defects of the patella and disabling knee pain, are good if CPM is used postoperatively. The clinical results using active motion postoperatively are not acceptable, especially not in patients with chondromalacia of the patella.

  • 92.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Masci, Lorenzo
    Öhberg, Lars
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Partial midportion Achilles tendon ruptures: new sonographic findings helpful for diagnosis.2011In: British Journal of Sports Medicine, ISSN 0306-3674, E-ISSN 1473-0480, Vol. 45, no 5, p. 429-432Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Partial Achilles tendon ruptures are not always easy to diagnose. A history including a sudden onset of pain, and/or relative weakness in plantar flexion force, are indicators. The most loaded side of the Achilles tendon is the dorsal side (skin side). OBJECTIVE: To evaluate the ultrasound (US) and Doppler (CD) findings in patients with a suspected partial rupture in the Achilles tendon. Material and METHODS: Seventeen patients (16 men and 1 woman) with a mean age of 36 years (range 23-71) were examined clinically and by US+CD because of midportion Achilles tendon pain. There was an acute onset in 14/17 patients, and all had painful weakness during tendon loading activity. RESULTS: In all patients the US examination showed a partial Achilles tendon rupture, presented as a disrupted dorsal (skin side) tendon line and an irregular tendon structure mainly located in the dorsal and mid-tendon. The size of the rupture varied from 1/3 to 2/3 of the tendon thickness. In the dorsal part of the tendon, corresponding to the region with disrupted tendon line and irregular structure, CD examination showed high blood flow-most often of a longitudinal character. Six of the patients were surgically treated, and macroscopical examination verified the ultrasound findings, showing disruption on the dorsal side, and a partial rupture in the dorsal and mid- tendon. CONCLUSIONS: Ultrasound and Doppler examination can be helpful tools to diagnose partial midportion Achilles tendon ruptures. The characteristic findings of a disrupted dorsal tendon line, and high blood flow in the structurally abnormal dorsal tendon, indicate a partial rupture.

  • 93.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Aerobic workout and bone mass in females1997In: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 7, no 6, p. 336-341Article in journal (Refereed)
    Abstract [en]

    This cross-sectional study aimed to investigate bone mass in females participating in aerobic workout. Twenty-three females (age 24.1 +/- 2.7 years), participating in aerobic workout for about 3 hours/week, were compared with 23 age-, weight- and height-matched non-active females. Areal bone mineral density (BMD) was measured in total body, head, whole dominant humerus, lumbar spine, right femoral neck, Ward's triangle, trochanter femoris, in specific sites in right femur diaphysis, distal femur, proximal tibia and tibial diaphysis, and bone mineral content (BMC) was measured in the whole dominant arm and right leg, using dual energy X-ray absorptiometry. The aerobic workout group had significantly (P < 0.05-0.01) higher BMD in total body (3.7%), lumbar spine (7.8%), femoral neck (11.6%), Ward's triangle (11.7%), trochanter femoris (9.6%), proximal tibia (6.8%) and tibia diaphysis (5.9%) compared to the non-active controls. There were no differences between the groups concerning BMD of the whole dominant humerus, femoral diaphysis, distal femur and BMC and lean mass of the whole dominant arm and right leg. Leaness of the whole dominant arm and leg was correlated to BMC of the whole dominant arm and right leg in both groups. In young females, aerobic workout containing alternating high and low impact movements for the lower body is associated with a higher bone mass in clinically important sites like the lumbar spine and hip, but muscle strengthening exercises like push-ups and soft-glove boxing are not associated with a higher bone mass in the dominant humerus. It appears that there is a skeletal adaptation to the loads of the activity.

  • 94.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Bone mass in female volleyball players: a comparison of total and regional bone mass in female volleyball players and nonactive females1997In: Calcified Tissue International, ISSN 0171-967X, E-ISSN 1432-0827, Vol. 60, no 4, p. 338-342Article in journal (Refereed)
    Abstract [en]

    The purpose of this cross-sectional study was to evaluate bone mass in female athletes participating in an impact loading sport (volleyball), and especially to investigate whether any changes in bone mass might be related to the type and magnitude of weightbearing loading and muscle strength. The volleyball group consisted of 13 first division players (age 20.9 +/- 3.7 years) training for about 8 hours/week, and the reference group consisted of 13 nonactive females (age 25.0 +/- 2.4 years) not participating in any kind of regular or organized sport activity. The groups were matched according to weight and height. Areal bone mineral density (BMD) was measured in total body, head, lumbar spine, femoral neck, Ward's triangle, trochanter, the whole femur, and humerus using dual-energy-X-ray absorptiometry. Isokinetic concentric peak torque of the quadricep and hamstring muscles was measured using an isokinetic dynamometer. Compared with the controls, the volleyball players had a significantly (P < 0.05-0.01) higher BMD of the total body (6.1%), lumbar spine (13.2%), femoral neck (15.8%), Ward's triangle (17.9%), trochanter (18.8%), nondominant femur (8.2%), and humerus (dominant 9.5%, nondominant 10.0%), but not of the head and the dominant whole femur. The dominant humerus showed significantly higher BMD than the nondominant humerus in both the volleyball and nonactive group (P < 0.05). There was no significant difference in muscle strength of the thigh between the two groups. In the nonactive group, muscle strength in the quadriceps, and especially hamstrings, was correlated to BMD of the adjacent bones (whole femur, hip sites) and also to distant sites (humerus). However, in the volleyball group there were no correlations between muscle strength and BMD of the adjacent bones, but quadricep strength correlated to BMD of the humerus. These results clearly show that young female volleyball players have a high bone mass. The demonstrated high bone mass seems to be related to the type of loading subjected to each BMD site. Muscle strength of the thigh seems to have little impact on BMD in female volleyball players.

  • 95.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Prolonged progressive calcaneal bone loss despite early weightbearing rehabilitation in patients surgically treated for Achilles tendinosis1998In: Calcified Tissue International, ISSN 0171-967X, E-ISSN 1432-0827, Vol. 62, no 2, p. 166-171Article in journal (Refereed)
    Abstract [en]

    We prospectively evaluated areal bone mineral density (BMD) of the calcaneus and calf-muscle strength (concentric and eccentric plantar flexion peak torque in Nm) in 10 recreational athletes (5 males and 5 females), mean age 40.9 years (range 26-55), who were selected to undergo surgical treatment for chronic Achilles tendinosis localized at the 2-6 cm level. Surgery was followed by immobilization in a plaster cast for 2 weeks, followed by flexibility training and slowly progressing strength training and weight-bearing activity. One patient was excluded after week 0 because of a new injury. Seven patients were back to their preinjury activity at the 26-week control, and eight patients at the 52-week control postoperatively. BMD in the calcaneus and calf-muscle strength on the injured and noninjured side was measured preoperatively (week 0) and postoperatively (weeks 2, 6, 16, 26, and 52). There were no significant differences in BMD between the injured and noninjured side at weeks 0, 2, and 6, but at weeks 16, 26, and 52, BMD was significantly (P < 0.05) lower (11.5%, 18.4%, and 16.4%, respectively) in the calcaneus of the injured side. Concentric and eccentric plantar flexion strength were significantly lower on the injured side preoperatively. Eccentric, but not concentric plantar flexion strength had recovered compared with the noninjured side 1 year postoperatively. Calf-muscle strength was not related to bone mass in the calcaneus. As a comparison, we used a group of 11 recreational athletes (10 males and 1 female), with a mean age of 46.1 years (range 28.9-58.5) who had been surgically treated for chronic Achilles tendinosis at the 2-6 cm level 39.5 +/- 11.8 months ago. In this group, there was no significant difference in BMD of the calcaneus between the injured and noninjured side. It seems that there was a delayed and prolonged calcaneal bone loss despite early weightbearing loading in patients surgically treated for chronic Achilles tendinosis at the 2-6 cm level. Around that time, when the Achilles tendon had healed (4-6 months) and the athletes returned to their sports, the calcaneal bone had a relatively low BMD and might possibly be vulnerable to heavy loadings. There were no signs of recovery 1 year postoperatively, but in a comparison group there were no significant side-to-side differences 39.5 months postoperatively.

  • 96.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Total and regional bone mass in female soccer players1996In: Calcified Tissue International, ISSN 0171-967X, E-ISSN 1432-0827, Vol. 59, no 6, p. 438-442Article in journal (Refereed)
    Abstract [en]

    This cross-sectional study investigated bone mass in female athletes participating in an impact-loading sport (soccer), and evaluated whether any changes in bone mass could be related to the type of weight-bearing loading and muscle strength. The group of soccer players consisted of 16 second-division female players (age 20.9 +/- 2.2 years) training for about 6 hours/week. The reference group consisted of 13 nonactive females (age 25.0 +/- 2.4 years) not participating in any kind of regular or organized sport activity. The groups were matched according to weight and height. Areal bone mineral density (BMD) was measured in total body, head, lumbar spine, femoral neck, Ward's triangle, trochanter, the whole femur and humerus, and in specific sites in femur diaphysis, distal femur, proximal tibia, and tibia diaphysis using dual X-ray absorptiometry. Isokinetic concentric peak torque of the quadriceps and hamstring muscles was measured using an isokinetic dynamometer. The soccer players had significantly (P < 0.05-0.01) higher BMD in the lumbar spine (10.7%), femoral neck (13.7%), Ward's triangle (19.6%), nondominant femur and humerus (8.2 and 8.0%, respectively), distal femur (12.6%), and proximal tibia (12.0%) compared with the nonactive women. There was no significant difference in muscle strength of the thigh between the two groups. In the nonactive group, muscle strength in the quadriceps and especially hamstrings, was correlated to BMD of the adjacent bones (whole femur, hip sites) and also to distant sites (humerus). In the soccer group, there were no correlations between muscle strength and BMD of the adjacent and distant bones. Soccer playing and training appears to have a beneficial effect on bone mass in young females, and it seems that there is a site-specific skeletal response to the type of loading subjected to each BMD site. Muscle strength in the thigh is not related to bone mass in female soccer players.

  • 97.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Pietilä, Tom
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Bone mass in the calcaneus after heavy loaded eccentric calf-muscle training in recreational athletes with chronic achilles tendinosis1999In: Calcified Tissue International, ISSN 0171-967X, E-ISSN 1432-0827, Vol. 64, no 5, p. 450-455Article in journal (Refereed)
    Abstract [en]

    In an ongoing prospective study of 14 recreational athletes (12 males and 2 females, mean age 44.2 +/- 7.1 years) with unilateral chronic Achilles tendinosis, we investigated the effect of treatment with heavy-loaded eccentric calf-muscle training. Pain during activity (recorded on a VAS scale) and isokinetic concentric and eccentric calf-muscle strength (peak torque at 90 degrees /second and 225 degrees /second) on the injured and noninjured side were evaluated. In this group of patients, we examined areal bone mineral density (BMD) of the calcaneus after 9 months (range 6-14 months) of training. BMD of the injured side (subjected to heavy-loaded eccentric training) was compared with BMD of the noninjured side. Before onset of heavy-loaded eccentric training, all patients had Achilles tendon pain which prohibited running activity, and significantly lower concentric and eccentric plantar flexion peak torque on the injured compared with the noninjured side. The training program consisted of 12 weeks of daily, heavy-loaded, eccentric calf-muscle training; thereafter the training was continued for 2-3 days/week. The clinical results were excellent-all 14 patients were back at their preinjury level with full running activity at the 3 month follow-up. The concentric and eccentric plantar flexion peak torque had increased significantly and did not significantly differ from the noninjured side at the 3 and 9 month follow-up. There were no significant side-to-side differences in BMD of the calcaneus. There was no significant relationship between BMD of the calcaneus and calf-muscle strength. As a comparison group, we used 10 recreational athletes (5 males and 5 females) mean age 40.9 years (range 26-55 years), who were selected for surgical treatment of chronic Achilles tendinosis localized at the 2-6 cm level. Their duration of symptoms and severity of disease were the same as in the experimental group. There were no significant side-to-side differences in BMD of the calcaneus preoperatively, but 12 months postoperatively BMD of the calcaneus was 16.4% lower at the injured side compared with the noninjured side. Heavy-loaded eccentric calf-muscle training resulted in a fast recovery in all patients, equaled the side-to-side differences in muscle strength, and was not associated with side-to-side differences in BMD of the calcaneus. In this group of middle-aged recreational athletes, BMD of the calcaneus was not related to calf-muscle strength.

  • 98.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Pietilä, Tom
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Long-term loading and regional bone mass of the arm in female volleyball players1998In: Calcified Tissue International, ISSN 0171-967X, E-ISSN 1432-0827, Vol. 62, no 4, p. 303-308Article in journal (Refereed)
    Abstract [en]

    In the present study, we compared the bone mineral content (BMC) and bone mineral density (BMD) in the arms of 11 female volleyball players (mean age 22.0 +/- 2.6 years) training for about 8 hours/week, and 11 nonactive females aged 24.6 +/- 3.1 years (mean +/- SD) not participating in regular or organized sport activity. Using dual X-ray absorptiometry (DXA), BMC was measured in the proximal and distal humerus, and BMD in the distal radius. Isokinetic concentric peak torque (highest value attained during 5 or 10 repetitions) of the rotator muscles of the shoulder and flexor and extensor muscles of the elbow were measured using an isokinetic dynamometer. The volleyball players had significantly higher BMC (P < 0.05) at the proximal humerus of the dominant arm compared with the nonactive group, but there were no differences between the groups in BMC of the distal humerus and BMD of the distal radius. In the volleyball players, BMC was significantly higher at the proximal humerus, at the distal humerus, and at the distal radius in the dominant compared with the nondominant arm. In the nonactive group, there were no significant differences in BMC and BMD between the dominant and nondominant arm at any site measured. Except for shoulder internal rotation strength and elbow flexion strength at 90 degrees/second that was higher in the dominant arm in the volleyball players, there were no significant differences in muscle strength of the rotator muscles of the shoulder and flexor and extensor muscles of the elbow between the dominant and nondominant arm in the volleyball players and nonactive controls. In the volleyball players, but not in the nonactive controls, there were several significant relationships between shoulder and elbow strength and BMC at the distal humerus of the dominant and especially the nondominant arm. These results show that young female volleyball players have a higher bone mass in the proximal humerus, distal humerus, and distal radius in the dominant compared with the nondominant arm, and a higher bone mass in the proximal humerus compared with nonactive controls. Muscle strength of the rotator muscles of the shoulder is not related to the higher bone mass in the proximal humerus of the dominant arm. Theoretically, the observed differences in bone mass can be related to the type of loading the skeleton undergoes when playing volleyball.

  • 99.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Ohberg, Lars
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Increased intratendinous vascularity in the early period after sclerosing injection treatment in Achilles tendinosis: a healing response?2006In: Knee Surg Sports Traumatol Arthrosc, ISSN 0942-2056, Vol. 14, no 4, p. 399-401Article in journal (Refereed)
  • 100.
    Alfredson, Håkan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Pietilä, Tom
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Jonsson, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Heavy-load eccentric calf muscle training for the treatment of chronic Achilles tendinosis1998In: American Journal of Sports Medicine, ISSN 0363-5465, E-ISSN 1552-3365, Vol. 26, no 3, p. 360-366Article in journal (Refereed)
    Abstract [en]

    We prospectively studied the effect of heavy-load eccentric calf muscle training in 15 recreational athletes (12 men and 3 women; mean age, 44.3 +/- 7.0 years) who had the diagnosis of chronic Achilles tendinosis (degenerative changes) with a long duration of symptoms despite conventional nonsurgical treatment. Calf muscle strength and the amount of pain during activity (recorded on a visual analog scale) were measured before onset of training and after 12 weeks of eccentric training. At week 0, all patients had Achilles tendon pain not allowing running activity, and there was significantly lower eccentric and concentric calf muscle strength on the injured compared with the noninjured side. After the 12-week training period, all 15 patients were back at their preinjury levels with full running activity. There was a significant decrease in pain during activity, and the calf muscle strength on the injured side had increased significantly and did not differ significantly from that of the noninjured side. A comparison group of 15 recreational athletes with the same diagnosis and a long duration of symptoms had been treated conventionally, i.e., rest, nonsteroidal antiinflammatory drugs, changes of shoes or orthoses, physical therapy, and in all cases also with ordinary training programs. In no case was the conventional treatment successful, and all patients were ultimately treated surgically. Our treatment model with heavy-load eccentric calf muscle training has a very good short-term effect on athletes in their early forties.

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