umu.sePublications
Change search
Refine search result
1 - 16 of 16
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1. Arumugam, Ashokan
    et al.
    Markström, Jonas
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Section of Physiotherapy.
    Häger, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Section of Physiotherapy.
    A novel test reliably captures hip and knee kinematics and kinetics during unanticipated/anticipated diagonal hops in individuals with anterior cruciate ligament reconstruction2020In: Journal of Biomechanics, ISSN 0021-9290, E-ISSN 1873-2380, Vol. 99, article id 109480Article in journal (Refereed)
    Abstract [en]

    Unanticipated land-and-cut maneuvers might emulate lower limb mechanics associated with anterior cruciate ligament (ACL) injury. Reliability studies on landing mechanics of such maneuvers are however lacking. This study investigated feasibility and within-session reliability of landing mechanics of a novel one-leg double-hop test, mimicking a land-and-cut maneuver, in individuals with ACL reconstruction (ACLR). Our test comprised a forward hop followed by a diagonal hop in either of two directions (medial/lateral) under anticipated and unanticipated conditions. Twenty individuals with a unilateral ACLR (aged 24.2 ± 4.2 years, 0.7-10.8 years post-surgery) performed three successful hops/direction per leg. We determined reliability (intraclass correlation coefficient [ICC]) and agreement (standard error of measurement [SEM]) of 3-dimensional hip and knee angles and moments during the deceleration phase of the land-and-cut maneuver (vulnerable for non-contact ACL injuries). Mean success rate for unanticipated hops was 71-77% and for anticipated hops 91-95%. Both limbs demonstrated moderate-excellent reliability (ICC 95% confidence intervals: 0.50-0.99) for almost all hip and knee peak angles and moments in all planes and conditions, with a few exceptions: poor-good reliability for hip and knee frontal and/or transverse plane variables, especially for lateral diagonal hops. The SEMs were ≤5° and ≤0.23 N·m/kg·m for most peak angles and moments, respectively. Our test seems feasible and showed satisfactory reliability for most hip and knee angles and moments; however, low knee abduction and internal rotation angles and moments, and moderate reliability of these moments deserve consideration. The test appears to challenge dynamic knee control and may prove valuable in evaluation during knee rehabilitation.

    Download full text (pdf)
    fulltext
  • 2.
    Arumugam, Ashokan
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Markström, Jonas L.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Häger, Charlotte K.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Introducing a novel test with unanticipated medial/lateral diagonal hops that reliably captures hip and knee kinematics in healthy women2019In: Journal of Biomechanics, ISSN 0021-9290, E-ISSN 1873-2380, Vol. 82, p. 70-79Article in journal (Refereed)
    Abstract [en]

    Despite a vast literature on one-leg hops and cutting maneuvers assessing knee control pre/post-injury of the anterior cruciate ligament (ACL), comprehensive and reliable tests performed under unpredictable conditions are lacking. This study aimed to: (1) assess the feasibility of an innovative, knee-challenging, one-leg double-hop test consisting of a forward hop followed by a diagonal hop (45°) performed medially (UMDH) or laterally (ULDH) in an unanticipated manner; and (2) determine within- and between-session reliability for 3-dimensional hip and knee kinematics and kinetics of these tests. Twenty-two healthy women (22.3 ± 3.3 years) performed three successful UMDH and ULDH, twice 1–4 weeks apart. Hop success rate was 69–84%. Peak hip and knee angles demonstrated moderate to excellent within-session reliability (intraclass correlation coefficient [ICC] 95% confidence interval [CI]: 0.67–0.99, standard error of measurement [SEM] ≤  3°) and poor to excellent between-session reliability (ICC CI: 0.22–0.94, SEM ≤ 3°) for UMDH and ULDH. The smallest real difference (SRD) was low (≤ 5°) for nearly all peak angles. Peak hip and knee moments demonstrated poor to excellent reliability (ICC CI: 0–0.97) and, in general, moments were more reliable within-session (SEM ≤ 0.14 N.m/kg.m, both directions) than between-session (SRD ≤ 0.43 N.m/kg.m). Our novel test was feasible and, in most but not all cases, provided reliable angle estimates (within-session > between-session, both directions) albeit less reliable moments (within-session > between-session, both directions). The relatively large hip and knee movements in the frontal and transverse planes during the unanticipated hops suggest substantial challenge of dynamic knee control. Thus, the test seems appropriate for evaluating knee function during ACL injury rehabilitation.

    Download full text (pdf)
    fulltext
  • 3.
    Markström, Jonas
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation.
    Grip, Helena
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Schelin, Lina
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Häger, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation.
    Elite women athletes with superior knee function present similar dynamic knee stability, although different movement strategies, when compared to controls2018In: 23rd annual Congress of the European College of Sport Science: Sport Science at the cutting edge, Dublin, Ireland, July 4-7, 2018: Book of Abstracts / [ed] Murphy, M.H., Boreham, C.A.G., De Vito, G., Tsolakidis, E., European College of Sport Sciences , 2018, p. 555-555Conference paper (Refereed)
    Abstract [en]

    INTRODUCTION: Neuromuscular training (NMT) of the lower limb is vital for athletes in learning correct movement technique to avoid risk of injury to the anterior cruciate ligament (ACL). The NMT aims for improved knee control while maintaining dynamic knee stability (DKS; resistance to linear/angular accelerations) during knee-challenging tasks. Assessing DKS is commonly attempted by evaluating discrete values of kinematic and kinetic variables during one-leg hops, but these measures may not sufficiently capture knee dynamics. We aimed to evaluate if elite women athletes who regularly perform NMT have greater DKS and/or different landing technique than normally active women who do not perform NMT, and if there are any correlations of DKS to peak knee extensor or flexor strength.

    METHODS: A motion capture system (Qualisys) synchronized with two force plates (Kistler) registered hip and knee 3D joint angles and moments during one-leg standardized lateral side hop landings for 39 women (19 athletes, 20 controls). Ten trials were performed for the dominant leg with hands behind their back holding a rope (25 cm), deemed successful following 3 s of single leg stance after landing without putting the contralateral foot on the ground or making major adjustments with the ipsilateral foot. DKS was evaluated using the inclination angle of the knee’s helical axis relative to the flexion-extension axis calculated for rotation intervals of 10 degrees, as has been proven useful (Grip and Häger, 2013), to quantify how much knee joint motion deviated from pure flexion-extension at landing. Hip and knee joint angles were analysed at initial contact (IC), and peak angles and peak moments were analysed during the deceleration phase of landing from IC to peak knee flexion (ind. t-tests, p < 0.05).

    RESULTS: Athletes had more successful hops, faster task execution, greater knee extension strength, greater hip flexion angle at IC, and higher peak moments of hip adduction and knee flexion than controls. There were however, no group differences in DKS or any significant correlations between DKS and knee extensor or flexor strength for any of the groups (r < absolute values of 0.41).

    CONCLUSION: Elite women athletes that perform NMT on a regular basis had superior knee function but similar DKS to controls when performing a sport-specific one-leg side hop maneuver. The greater hip flexion at IC for athletes shows a different movement strategy for landing preparation. Potential benefits of NMT in sports contexts, e.g. less ACL injuries (Sugimoto et al., 2016), may be due to movement alterations of the hip to increase landing control to avoid positions that strain the ACL rather than improving DKS. Further emphasis on knee-specific landing control may be important to also improve DKS, which seems unrelated to strength.

  • 4.
    Markström, Jonas
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Section of Physiotherapy.
    Grip, Helena
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Schelin, Lina
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Statistics.
    Häger, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Section of Physiotherapy.
    Individuals With an Anterior Cruciate Ligament-Reconstructed Knee Display Atypical Whole Body Movement Strategies but Normal Knee Robustness During Side-Hop Landings: A Finite Helical Axis Analysis2020In: American Journal of Sports Medicine, ISSN 0363-5465, E-ISSN 1552-3365, Vol. 48, no 5, p. 1117-1126Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Atypical knee joint biomechanics after anterior cruciate ligament reconstruction (ACLR) are common. It is, however, unclear whether knee robustness (ability to tolerate perturbation and maintain joint configuration) and whole body movement strategies are compromised after ACLR.

    PURPOSE: To investigate landing control after ACLR with regard to dynamic knee robustness and whole body movement strategies during sports-mimicking side hops, and to evaluate functional performance of hop tests and knee strength.

    STUDY DESIGN: Controlled laboratory study.

    METHODS: An 8-camera motion capture system and 2 synchronized force plates were used to calculate joint angles and moments during standardized rebound side-hop landings performed by 32 individuals with an ACL-reconstructed knee (ACLR group; median, 16.0 months after reconstruction with hamstring tendon graft [interquartile range, 35.2 months]) and 32 matched asymptomatic controls (CTRL). Dynamic knee robustness was quantified using a finite helical axis approach, providing discrete values quantifying divergence of knee joint movements from flexion-extension (higher relative frontal and/or transverse plane motion equaled lower robustness) during momentary helical rotation intervals of 10°. Multivariate analyses of movement strategies included trunk, hip, and knee angles at initial contact and during landing and hip and knee peak moments during landing, comparing ACLR and CTRL, as well as legs within groups.

    RESULTS: Knee robustness was lower for the first 10° motion interval after initial contact and then successively stabilized for both groups and legs. When landing with the injured leg, the ACLR group, as compared with the contralateral leg and/or CTRL, demonstrated significantly greater flexion of the trunk, hip, and knee; greater hip flexion moment; less knee flexion moment; and smaller angle but greater moment of knee internal rotation. The ACLR group also had lower but acceptable hop and strength performances (ratios to noninjured leg >90%) except for knee flexion strength (12% deficit).

    CONCLUSION: Knee robustness was not affected by ACLR during side-hop landings, but alterations in movement strategies were seen for the trunk, hip, and knee, as well as long-term deficits in knee flexion strength.

    CLINICAL RELEVANCE: Knee robustness is lowest immediately after landing for both the ACLR group and the CTRL and should be targeted in training to reduce knee injury risk. Assessment of movement strategies during side-hop landings after ACLR should consider a whole body approach.

  • 5.
    Markström, Jonas
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation.
    Grip, Helena
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Schelin, Lina
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Häger, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation.
    Similar dynamic knee stability but different movement strategies and between-leg asymmetries for hip and knee joints for ACL-reconstructed persons relative to knee-healthy controls2018In: 8th World Congress of Biomechanics, Dublin, July 8-12, 2018, 2018Conference paper (Refereed)
    Abstract [en]

    Introduction: Jumping involves complex control processes of sensory input and feedback with coordination of multiple joints. Following anterior cruciate ligament reconstruction (ACLR), altered movement strategies identified by kinematics and/or kinetics unload the injured leg and increase demands on nearby joints. Dynamic knee stability (DKS; resistance to linear/angular accelerations) has not been evaluated for ACLR persons during sport-similar tasks. It is therefore unknown if there is true instability or altered task execution, e.g. due to fear. We hypothesized that DKS following rehabilitation after ACLR would be similar to that of knee-healthy controls, but with prevailing protective movement strategies.

    Methods: A motion capture system synchronized with two force plates registered hip and knee 3D angles and moments during a one-leg standardized side hop for 30 ACLR persons (7-129 months post-reconstruction) and 30 controls. EMG provided mean knee extensor and flexor muscle activation patterns and co-contraction ratios and indexes before (50ms window) and during landing. DKS was evaluated using a helical axis rotation interval of 10˚ to describe how much knee kinematics diverges from flexion-extension. DKS and muscle activation variables were analysed with t-tests. Hip and knee movement strategies were analysed for angles at initial contact, peak angles during landing, and peak moments during landing with MANOVAs between and within groups (p<0.05).

    Results: No significant differences in DKS was found between groups. A significant main effect of group was however observed for angles at initial contact (p=0.028) with ACLR showing greater hip and knee flexion than controls. A significant main effect of group was also found during landing for peak angles (p=0.001) and moments (p=0.017) with ACLR displaying greater hip flexion and knee internal rotation moment, and also greater mean knee flexor activation than controls (p=0.049). No group differences in muscle activation patterns were shown before landing. ACLR had between-leg asymmetries at initial contact (p=0.010) with greater hip flexion, and asymmetries for peak angles (p=0.008) and moments (p=0.030) during landing with greater hip flexion angle, greater hip flexion moment and less knee flexion moment in the injured leg.

    Discussion: Despite similar DKS, ACLR displayed different movement strategies and asymmetries relative to controls, which indicates a task-coping strategy in preparation for and during landing. The greater hip and knee flexion angles at initial contact in relation to the greater hip flexion moment and knee flexor activation that followed may have increased knee joint stiffness, which could explain the similar DKS relative to controls. The between-leg asymmetry with greater reliance on the hip and simultaneous unloading of the knee further supports a coping strategy for ACLR. Further attention should be given to the hip during rehabilitation for ACLR persons to avoid future injuries due to movement compensation.

  • 6.
    Markström, Jonas
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Grip, Helena
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Schelin, Lina
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Statistics.
    Häger, Charlotte K.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Dynamic knee control and movement strategies in athletes and non‐athletes in side hops: implications for knee injury2019In: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 29, no 8, p. 1181-1189Article in journal (Refereed)
    Abstract [en]

    Athletes exposed to rapid maneuvers need a high level of dynamic knee stability and robustness, while also controlling whole body movement, to decrease the risk of non‐contact knee injury. The effects of high‐level athletic training on such measures of movement control have not, however, been thoroughly evaluated. This study investigated whether elite athletes (who regularly perform knee‐specific neuromuscular training) show greater dynamic knee robustness and/or different movement strategies than non‐athletic controls, in relation to overall knee function. Thirty‐nine women (19 athletes, 20 controls) performed standardized rebound side hops (SRSH) while a motion capture system synchronized with two force plates registered three‐dimensional trunk, hip, and knee joint angles and moments. Dynamic knee robustness was evaluated using finite helical axis (FHA) inclination angles extracted from knee rotation intervals of 10°, analyzed with independent t tests. Angle and moment curves were analyzed with inferential methods for functional data. Athletes had superior knee function (less laxity, greater hop performances, and strength) but presented similar FHA inclination angles to controls. Movement strategies during the landing phase differed; athletes presented larger (a) hip flexion angles (during 9%‐29% of the phase), (b) hip adduction moments (59%‐99%), (c) hip internal rotation moments (83%‐89%), and (d) knee flexion moments (79%‐93%). Thus, elite athletes may have a greater ability than non‐athletes to keep the knee robust while performing SRSH more efficiently through increased engagement of the hip. However, dynamic knee robustness associated with lower FHA inclination angles still show room for improvement, thus possibly decreasing knee injury risk.

    Download full text (pdf)
    fulltext
  • 7.
    Markström, Jonas L.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Section of Physiotherapy.
    Movement strategies and dynamic knee control after anterior cruciate ligament injury: a three-dimensional biomechanical analysis2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background: Rupture of the anterior cruciate ligament (ACL) is common and mainly occurs in non-contact situations in sports, often due to momentarily poor movement control. Assessment of movement quality during sport-like tasks iscrucial to understand how to decrease the high risk of reinjury for ACL-injured persons, but also how to prevent primary injury. This thesis addresses movement quality after ACL injury and includes development and evaluation of a novel standardized rebound side hop test (SRSH) for reliability and agreement of landing mechanics, and compares these outcomes between asymptomatic persons with different athletic levels, and between different hop tests.

    Methods: This thesis involves five papers based on two separate data collections performed in a motion analysis laboratory. Paper I is a long-term follow up of ACL-injured persons treated with or without ACL reconstruction (ACLR) compared to asymptomatic persons (total N = 99, age 35-63), while papers II-V included ACLR persons, and asymptomatic elite athletes and non-athletes (total N = 79, age 17-34). A motion capture system synchronized with force plates and surface electromyography (EMG) registered trunk, hip and knee angles and moments and knee muscle activity during the hop for distance, vertical hop, and SRSH. Novel measures of dynamic knee robustness were also evaluated using finite helical axis inclination angles extracted from knee rotation intervals of 10˚.

    Results: On average 23 years after injury, ACL injured persons performed the vertical hop with diverse angles compared to controls and their non-injured leg.The younger groups of ACLR persons and controls generally displayed excellent reliability and agreement for SRSH landing mechanics. These outcomes differed between the groups, and between legs for ACLR persons, despite similar dynamic knee robustness and acceptable knee function outcomes. Curve analyses further displayed differences between athletes and non-athletes, mainly with greater hip moments for athletes, although with similar values for dynamic knee robustness. Finally, greater knee angles and moments considered strenuous for the ACL were evident during the first rebound landing in SRSH compared to the other landings.

    Conclusions: Persons who have suffered an ACL injury, regardless of whether treated with ACLR or not, appear to use task-coping strategies in preparation for and during landings to decrease knee joint loading, probably to preserve dynamic knee robustness. More attention should be given to the trunk and hip in clinics when evaluating movement quality after ACL injury to reduce the risk of future injuries due to movement compensation. High-level athletic training may also improve the ability to maintain dynamic knee robustness whilst performing a sport-like side-to-side task more efficiently through increased engagement of the hip. Finally, side hop landings should be assessed when evaluating and correcting for erroneous landing mechanics to improve knee landing control.

    Download full text (pdf)
    fulltext
    Download (pdf)
    spikblad
    Download (png)
    presentationsbild
  • 8.
    Markström, Jonas L.
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Grip, Helena
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Schelin, Lina
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Statistics.
    Häger, Charlotte K.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Individuals with anterior cruciate ligament reconstruction adopt different movement strategies but display robust knees during side hop landingsManuscript (preprint) (Other academic)
  • 9.
    Markström, Jonas L.
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Schelin, Lina
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Statistics.
    Häger, Charlotte K.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    A novel standardised side hop test reliably evaluates landing mechanics for anterior cruciate ligament reconstructed persons and controls2018In: Sports Biomechanics, ISSN 1476-3141, E-ISSN 1752-6116Article in journal (Refereed)
    Abstract [en]

    We propose a novel one-leg standardised rebound side-hop test (SRSH) specifically designed for detailed analysis of landing mechanics. Anterior cruciate ligament reconstructed persons (ACLR, n = 30) and healthy-knee controls (CTRL, n = 30) were tested for within-session and test-retest (CTRL only, n = 25) reliability and agreement. Trunk, hip and knee angles and moments in sagittal, frontal, and transversal planes during landing, including time to stabilisation (TTS), were evaluated using intra-class correlations (ICCs), average within-person standard deviations (SW) and minimal differences. Excellent within-session reliability were found for angles in both groups (most ICCs > 0.90, SW ≤ 5°), and excellent to good for moments (most ICCs > 0.80, SW ≤ 0.34 Nm/kg). Only knee internal rotation moment showed poor reliability (ICC < 0.4). Test-retest results were excellent to fair for all angles and moments (ICCs 0.47–0.91, SW < 5° and ≤ 0.25 Nm/kg), except for peak trunk lateral bending angle and knee internal rotation moment. TTS showed excellent to fair within-session reliability but poor test-retest results. These results, with a few exceptions, suggest promising potential of evaluating landing mechanics during the SRSH for ACLR and CTRL, and emphasise the importance of joint-specific movement control variables in standardised tasks.

    Download full text (pdf)
    fulltext
  • 10.
    Markström, Jonas L.
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Tengman, Eva
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Grip, Helena
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Schelin, Lina
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Statistics.
    Häger, Charlotte K.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    A comparison of knee joint kinematics and kinetics during landings in three one-leg hop tests (hop for distance, vertical hop and side hop) performed by female elite floorball athletes2016In: XXI ISEK Congress: Bridges to Innovation, 2016Conference paper (Refereed)
  • 11.
    Markström, Jonas L.
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Tengman, Eva
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Häger, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    ACL-reconstructed and ACL-deficient individuals show differentiated trunk, hip, and knee kinematics during vertical hops more than 20 years post-injury2018In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 26, no 2, p. 358-367Article in journal (Refereed)
    Abstract [en]

    PURPOSE: Little is known regarding movement strategies in the long term following injury of the anterior cruciate ligament (ACL), and even less about comparisons of reconstructed and deficient knees in relation to healthy controls. The present purpose was to compare trunk, hip, and knee kinematics during a one-leg vertical hop (VH) ~20 years post-ACL injury between persons treated with surgery and physiotherapy (ACLR), solely physiotherapy (ACLPT), and controls (CTRL). Between-leg kinematic differences within groups were also investigated.

    METHODS: Sixty-six persons who suffered unilateral ACL injury on average 23 ± 2 years ago (32 ACLR, 34 ACLPT) and 33 controls performed the VH. Peak trunk, hip, and knee angles during Take-off and Landing phases recorded with a 3D motion capture system were analysed with multivariate statistics.

    RESULTS: Significant group effects during both Take-off and Landing were found, with ACLPT differing from CTRL in Take-off with a combination of less knee flexion and knee internal rotation, and from both ACLR and CTRL in Landing with less hip and knee flexion, knee internal rotation, and greater hip adduction. ACLR also presented different kinematics to ACLPT and CTRL in Take-off with a combination of greater trunk flexion, hip flexion, hip internal rotation, and less knee abduction, and in Landing with greater trunk flexion and hip internal rotation. Further, different kinematics and hop height were found between legs within groups in both Take-off and Landing for both ACL groups, but not for CTRL.

    CONCLUSION: Different kinematics for the injured leg for both ACL groups compared to CTRL and between treatment groups, as well as between legs within treatment groups, indicate long-term consequences of injury. Compensatory mechanisms for knee protection seem to prevail over time irrespective of initial treatment, possibly increasing the risk of re-injury and triggering the development of osteoarthritis. Detailed investigation of movement strategies during the VH provides important information and a more comprehensive evaluation of knee function than merely hop height. More attention should also be given to the trunk and hip in clinics when evaluating movement strategies after ACL injury.

    LEVEL OF EVIDENCE: Prospective cohort study, Level II.

    Download full text (pdf)
    fulltext
  • 12.
    Markström, Jonas L.
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Tengman, Eva
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Häger, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    One-leg lateral side-hops induce greater demands on knee landing control than hops in other directions as demonstrated in athletic and non-athletic females with or without injury of the anterior cruciate ligamentManuscript (preprint) (Other academic)
  • 13.
    Markström, Jonas L.
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Tengman, Eva
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Häger, Charlotte K.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    A kinematic analysis of one-leg vertical jump on average 23 years after injury of the anterior cruciate ligament2015In: Gait & Posture: 24th Annual Meeting of ESMAC 2015 Abstracts, 2015, Vol. 42, p. 1-2, article id Session OS01 Best-Paper-Session - OutcomesConference paper (Refereed)
  • 14.
    Markström, Jonas
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Olsson, Carl-Johan
    Umeå University, Faculty of Social Sciences, Centre for Population Studies (CPS).
    Countermovement jump peak force relative to body weight and jump height as predictors for sprint running performances: (in)homogeneity of track and field athletes?2013In: Journal of Strength and Conditioning Research, ISSN 1064-8011, E-ISSN 1533-4287, Vol. 27, no 4, p. 944-953Article in journal (Refereed)
    Abstract [en]

    The purpose of this study was to investigate: (1) If variables from one-leg drop jump (DJ), DJ, squat jump (SJ), and counter movement jump (CMJ) tests can predict sprint performances for sprinters. (2) If sprinters and jumpers can be distinguished based on variables from one-leg DJ, DJ, SJ, and CMJ tests, also if sprinters and throwers can be distinguished based on variables from stiff leg jump (SLJ), SJ, and CMJ tests. A single linear regression and multiple linear regression analysis approach with models including two or three variables were used when predicting sprint performances. Five elite sprinters (1 female) participated in the first subexamination and five sprinters (1 female) vs five jumpers and six sprinters vs. six throwers (4 females) participated in the second. The force variable CMJ peak force relative to body weight significantly predicted the sprint performances maximal running velocity through 10 m (Vmax10m) and 60 m time. Vmax10m was also predicted by CMJ height. Jump heights from SJ and DJ did not predict sprint performances. The between group analysis of the athletes showed a non-significant group difference with respect to the jump variables. However, planned comparisons between sprinters and throwers showed significant differences on a number of SLJ variables. When constructing training programs for sprinters, aim should be to improve CMJ peak force and CMJ height because of the prediction of Vmax10m and 60 m time, presumably due to velocity specificity components.

  • 15.
    Markström, Jonas
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation.
    Tengman, Eva
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation.
    Häger, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation.
    Different dynamic knee stability and frontal plane kinematics and kinetics between landings in common one-leg hops for ACL-reconstructed women and knee-healthy controls2018In: 8th World Congress of Biomechanics, Dublin, July 8-12, 2018, 2018Conference paper (Other academic)
  • 16.
    Pini, Alessia
    et al.
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Statistics.
    Markström, Jonas
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation.
    Schelin, Lina
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Statistics.
    Test-retest reliability measures for curve data: an overview with recommendations and supplementary code.2019In: Sports Biomechanics, ISSN 1476-3141, E-ISSN 1752-6116, p. 1-22Article in journal (Refereed)
    Abstract [en]

    The purpose of this paper is to provide an overview of available methods for reliability investigations when the outcome of interest is a curve. Curve data, or functional data, is commonly collected in biomechanical research in order to better understand different aspects of human movement. Using recent statistical developments, curve data can be analysed in its most detailed form, as functions. However, an overview of appropriate statistical methods for assessing reliability of curve data is lacking. A review of contemporary literature of reliability measures for curve data within the fields of biomechanics and statistics identified the following methods: coefficient of multiple correlation, functional limits of agreement, measures of distance and similarity, and integrated pointwise indices (an extension of univariate reliability measures to curve data, inclusive of Pearson correlation, intraclass correlation, and standard error of measurement). These methods are briefly presented, implemented (R-code available as supplementary material) and evaluated on simulated data to highlight advantages and disadvantages of the methods. Among the identified methods, the integrated intraclass correlation and standard error of measurement are recommended. These methods are straightforward to implement, enable results over the domain, and consider variation between individuals, which the other methods partly neglect.

    Download full text (pdf)
    fulltext
1 - 16 of 16
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf