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  • 1.
    Bjerke, Joakim
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Department of Physiotherapy, School of Health Education & Social Work, Sør-Trøndelag University College, Trondheim, Norway.
    Öhberg, Fredrik
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Nilsson, Kjell G
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Foss, Olav A
    Orthopaedic Research Centre, Trondheim University Hospital, Trondheim, Norway.
    Stensdotter, Ann-Katrin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Department of Physiotherapy, School of Health Education & Social Work, Sør-Trøndelag University College, Trondheim, Norway.
    Peak knee flexion angles during stair descent in TKA patients2014In: The Journal of Arthroplasty, ISSN 0883-5403, E-ISSN 1532-8406, Vol. 29, no 4, p. 707-711Article in journal (Refereed)
    Abstract [en]

    Reduced peak knee flexion during stair descent (PKSD) is demonstrated in subjects with total knee arthroplasty (TKA), but the underlying factors are not well studied. 3D gait patterns during stair descent, peak passive knee flexion (PPKF), quadriceps strength, pain, proprioception, demographics, and anthropometrics were assessed in 23 unilateral TKA-subjects ~ 19 months post-operatively, and in 23 controls. PKSD, PPKF and quadriceps strength were reduced in the TKA-side, but also in the contralateral side. A multiple regression analysis identified PPKF as the only predictor (57%) to explain the relationship with PKSD. PPKF was, however sufficient for normal PKSD. Deficits in quadriceps strength in TKA-group suggest that strength is also contributing to smaller PKSD. Increased hip adduction at PKSD may indicate both compensatory strategy and reduced hip strength.

  • 2.
    Bjerke, Joakim
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Department of Physiotherapy, School of Health Education & Social Work, Sør-Trøndelag University College, Trondheim, Norway.
    Öhberg, Fredrik
    Department of Biomedical Engineering & Informatics, Umeå University Hospital, Umeå, Sweden.
    Nilsson, Kjell G
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Stensdotter, Ann-Katrin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Department of Physiotherapy, School of Health Education & Social Work, Sør-Trøndelag University College, Trondheim, Norway.
    Compensatory strategies for muscle weakness during stair ascent in subjects with total knee arthroplasty2014In: The Journal of Arthroplasty, ISSN 0883-5403, E-ISSN 1532-8406, Vol. 29, no 7, p. 1499-1502Article in journal (Refereed)
    Abstract [en]

    Subjects with total knee arthroplasty (TKA) exhibit decreased quadriceps and hamstring strength. This may bring about greater relative effort or compensatory strategies to reduce knee joint moments in daily activities. To study gait and map out the resource capacity, knee muscle strength was assessed by maximal voluntary concentric contractions, and whole body kinematics and root mean square (RMS) electromyography (EMG) of vastus lateralis and semitendinosus were recorded during stair ascent in 23 unilateral TKA-subjects ~19months post-operation, and in 23 healthy controls. Muscle strength and gait velocity were lower in the TKA group, but no significant group differences were found in RMS EMG or forward trunk lean. The results suggest that reduced walking velocity sufficiently compensated for reduced knee muscle strength.

  • 3.
    Bjerke, Joakim
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Department of Physiotherapy, School of Health Education & Social Work, Sør-Trøndelag University College, Trondheim, Norway.
    Öhberg, Fredrik
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Nilsson, Kjell G
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Stensdotter, Ann-Katrin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Department of Physiotherapy, School of Health Education & Social Work, Sør-Trøndelag University College, Trondheim, Norway.
    Gait on soft versus hard surface after total knee arthroplastyManuscript (preprint) (Other academic)
    Abstract [en]

    Asymmetric gait patterns are common following total knee arthroplasty (TKA). Gait on even and hard surface is primarily characterized by reduced peak knee flexion in the prosthetic knee, increased contralateral knee adduction angle, and decreased walking speed compared to controls. Natural conditions may however lead to different strategies. Therefore, the objective of the present study was to explore how gait patterns may differ when walking on a soft surface. Methods: 3D kinematics during gait on hard and soft surface were assessed in 23 unilateral TKA-subjects ~19 months post-operative, and in 23 controls. Results: Gait characteristics in TKA-subjects that differed from controls observed on hard surface were amplified on soft surface. Flexion in the prosthetic knee was further decreased and a tendency towards reduced flexion in the contralateral knee was observed. Knee and hip adduction were not affected by surface conditions nevertheless there was a difference between groups, in particular with regard to the prosthetic side. In addition, step width increased on soft surface in TKA-subjects. Conclusion: Gait on an even and soft surface did not amplify asymmetries in TKA-subjects, but decreased knee flexion and increased step-width, albeit with similar gait speed as the control group suggests that the soft surface provided a small but significant challenge making the TKA-subjects precautious.

  • 4.
    Bjerke, Joakim
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Department of Physiotherapy, Faculty of Health and Social Sciences, Norwegian University of Science and Technology, Trondheim, Norway.
    Öhberg, Fredrik
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Nilsson, Kjell G
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Stensdotter, Ann-Katrin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation. epartment of Physiotherapy, Faculty of Health and Social Sciences, Norwegian University of Science and Technology, Trondheim, Norway .
    Walking on a compliant surface does not enhance kinematic gait asymmetries after unilateral total knee arthroplasty2016In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 24, no 8, p. 2606-2613Article in journal (Refereed)
    Abstract [en]

    PURPOSE: To investigate gait asymmetries and the effect of walking on compliant surfaces in individuals with unilateral total knee arthroplasty (TKA), hypothesizing that asymmetries would increase as an effect of the compliant surface.

    METHODS: Individuals with unilateral TKA ~19 months post-operative (n = 23, median age 59 years) recruited from one orthopaedic clinic and age- and gender-matched healthy individuals without knee complaints (n = 23, median age 56 years) walked at comfortable speed on a hard surface and on a compliant surface. 3D kinematic analyses were made for knee and hip angles in sagittal and frontal planes, stance time, step length, and gait velocity.

    RESULTS: Shorter stance time (p < 0.01) and less peak knee flexion (p < 0.001) at weight bearing acceptance was found in the prosthetic side compared with the contralateral side. Larger knee (p < 0.01) and hip (p < 0.001) adduction was found compared with healthy controls. Neither asymmetries between the prosthetic and the contralateral side nor differences compared with healthy controls were enhanced when walking on compliant surfaces compared with hard surfaces.

    CONCLUSION: The TKA group adapted their gait to compliant surfaces similarly to healthy controls. Gait asymmetries in the TKA group observed on hard surface were not enhanced, and adduction in hip and knee joints did not increase further as an effect of walking on compliant surfaces. Thus, unfavourable knee joint loading did not increase when walking on a compliant surface. This implies that recommendations for walking on soft surfaces to reduce knee joint loading are not counteracted by increased gait asymmetries and unfavourable joint loading configurations.

    LEVEL OF EVIDENCE: III.

  • 5.
    Grenholm, Anton
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Stensdotter, Ann-Katrin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Häger-Ross, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Kinematic analyses during stair descent in young women with patellofemoral pain2009In: Clinical Biomechanics, ISSN 0268-0033, E-ISSN 1879-1271, Vol. 24, no 1, p. 88-94Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Compensatory movement strategies may develop in response to pain to avoid stress on the affected area. Patellofemoral pain is characterised by intermittent periods of pain and the present study addresses whether long-term pain leads to compensatory movement strategies that remain even when the pain is absent. METHOD: Lower extremity kinematics in three dimensions was studied in stair descent in 17 women with patellofemoral and in 17 matched controls. A two-dimensional geometric model was constructed to normalise kinematic data for subjects with varying anthropometrics when negotiating stairs of fixed proportions. RESULTS: There were minor differences in movement patterns between groups. Knee joint angular velocity in the stance leg at foot contact was lower and the movement trajectory tended to be jerkier in the patellofemoral group. The two-dimensional model showed greater plantar flexion in the swing leg in preparation for foot placement in the patellofemoral group. INTERPRETATION: The results indicate that an altered stair descent strategy in the patellofemoral group may remain also in the absence of pain. The biomechanical interpretation presumes that the strategy is aimed to reduce knee joint loading by less knee joint moment and lower impact force.

  • 6.
    Stensdotter, Ann Katrin
    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.
    Hodges, P
    Häger Ross, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Quadriceps activity and movement in response to unpredictable sagital support-surface translations2007Conference paper (Other academic)
  • 7.
    Stensdotter, Ann Katrin
    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, Radiation Physics.
    Hodges, P W
    Häger-Ross, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Quadriceps activity and movement reactions in response to unpredictable sagittal support-surface translations in women with patellofemoral pain.2008In: Journal of Electromyography & Kinesiology, ISSN 1050-6411, E-ISSN 1873-5711, Vol. 18, no 2, p. 298-307Article in journal (Refereed)
    Abstract [en]

    Patellofemoral pain (PFP) may be related to unfavorable knee joint loading. Delayed and/or reduced activity of vastus medialis obliquus (VMO) and different movement patterns have been identified in individuals with PFP in some studies, whereas other studies have failed to show a difference compared to non-affected controls. The discrepancy between study results may depend on the different tasks that have been investigated. No previous study has investigated these variables in postural responses to unpredictable perturbations in PFP. Whole body three dimensional kinematics and surface EMG of quadriceps muscles activation was studied in postural responses to unpredictable support surface translations in 17 women with PFP who were pain free at the time of testing, and 17 matched healthy controls. The results of the present study showed earlier onset of VMO activity and associated changes in kinematics to anterior platform translation in the PFP subjects. We suggest that the relative timing between the portions quadriceps muscles may be task specific and part of an adapted response in attempt to reduce knee joint loading. This learned response appears to remain even when the pain is no longer present.

  • 8.
    Stensdotter, Ann Katrin
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Hodges, P
    Öhberg, Fredrik
    Häger-Ross, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Quadriceps EMG in open and closed kinetic chain in women with patellofemoral pain2007Conference paper (Other academic)
  • 9.
    Stensdotter, Ann-Katrin
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Andersson, Per-Ivar
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Rydh, Anders
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Häger-Ross, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Q-angle variations in standing and supine positions and for different measurement methods in women with and without patellofemoral pain2009In: Advances in Physiotherapy, ISSN 1403-8196, E-ISSN 1651-1948, Vol. 11, no 2, p. 88-96Article in journal (Refereed)
  • 10.
    Stensdotter, Ann-Katrin
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Sør-Trøndelag University College, Trondheim, Norway.
    Bjerke, Joakim
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Sør-Trøndelag University College, Trondheim, Norway.
    Djupsjobacka, Mats
    Postural sway in single-limb and bilateral quiet standing after unilateral total knee arthroplasty2015In: Gait & Posture, ISSN 0966-6362, E-ISSN 1879-2219, Vol. 41, no 3, p. 769-773Article in journal (Refereed)
    Abstract [en]

    Aim: To investigate whether total knee arthroplasty (TKA) was associated with stability in single-limb stance and whether reduced stability in single-limb stance was associated with increased postural sway in bilateral quiet standing.

    Methods: 3D kinematics for center of mass was used to assess postural sway in 23 subjects with TKA and 23 controls. Tests included bilateral quiet standing with and without vision and on a compliant surface, and single-limb stance.

    Results: 30% of the subjects in the TKA group were unable to maintain single-limb stance for 20 s on any leg. Of the 70% in the TKA group able to stand on one leg, mean sway velocity in the medio-lateral direction was marginally higher for the prosthetic side (p = .02), but no differences were found between the TKA and the control group in single-limb stance. Performance in bilateral quiet standing was similar in TKA-subjects, able as well as unable to stand on one leg, and controls. Reduced quadriceps strength in the contralateral leg, higher BMI, and older age predicted failure to maintain single-limb stance.

    Conclusion: In subjects able to stand on one leg, performance was considered comparable between the prosthetic and contralateral side and between groups. Inability to stand on one leg did not affect postural sway in bilateral quiet standing. The results suggest that inability to maintain single-limb stance is explained by reduced physical capacity rather than the knee condition in itself. The present study emphasizes the importance of physical activity to improve strength and functional capacity.

  • 11.
    Stensdotter, Ann-Katrin
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Department of Physiotherapy, School of Health Education & Social Work, Sør-Trøndelag University College, Trondheim, Norway.
    Bjerke, Joakim
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Department of Physiotherapy, School of Health Education & Social Work, Sør-Trøndelag University College, Trondheim, Norway.
    Djupsjöbacka, Mats
    Centre for Musculoskeletal Research, Department of Occupational and Public Health Sciences, University of Gävle.
    Postural sway in single-limb and bilateral quiet standing after unilateral total knee arthroplastyManuscript (preprint) (Other academic)
    Abstract [en]

    Aim: To investigate the effects of total knee arthroplasty (TKA) on single limb stance and whether reduced stability in single-limb stance may increase postural sway in bilateral quiet standing.                                                              

    Methods: 3D kinematics for center of mass was used to assess postural sway in 23 subjects with TKA and 23 controls. Tests included bilateral quiet standing with and without vision and on a yielding surface, and single-limb stance.                                                                    

    Results: 30% of the subjects in the TKA group were unable to maintain single-limb stance for 20 s on any leg. Of the 70%  in the TKA group able to stand on one leg, mean sway velocity in the medio-lateral direction was higher when standing on the prosthetic leg (p=.02), but no differences were found between the TKA and the control group in single-limb stance. Performance in bilateral quiet standing was similar in TKA-subjects able as well as unable to stand on one leg and controls. Reduced quadriceps strength in the contralateral leg, higher BMI, and older age predicted failure to maintain single-limb stance.                  

    Conclusion: In subjects able to stand on one leg, performance was considered comparable between the prosthetic and contralateral limb and between groups. Inability to stand on one leg did not affect postural sway in bilateral quiet standing. The results suggest that inability to maintain single-limb stance is explained by reduced physical capacity rather than the knee condition in itself. The present study emphasizes the importance of physical activity to improve strength and functional capacity.

  • 12.
    Stensdotter, Ann-Katrin
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Dalén, Tore
    Holmgren, Christer
    Häger-Ross, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Knee angle and force vector-dependent variations in open and closed kinetic chain for M. popliteus activation.2008In: Journal of Orthopaedic Research, ISSN 1554-527X, Vol. 26, no 2, p. 217-24Article in journal (Other academic)
  • 13.
    Stensdotter, Ann-Katrin
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Guerra, Jamie
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Häger-Ross, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Limb support in response to balance provocations in women with patellofemoral pain2008In: Advances in physiotherapy, ISSN 1403-8196, Vol. 11, no 2, p. 97-103Article in journal (Refereed)
  • 14.
    Stensdotter, Ann-Katrin
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Hodges, Paul
    Mellor, Rebecca
    Sundelin, Gunnevi
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Häger-Ross, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Quadriceps activation in closed and in open kinetic chain exercise.2003In: Medicine & Science in Sports & Exercise, ISSN 0195-9131, E-ISSN 1530-0315, Vol. 35, no 12, p. 2043-2047Article in journal (Refereed)
    Abstract [en]

    PURPOSE: For treatment of various knee disorders, muscles are trained in open or closed kinetic chain tasks. Coordination between the heads of the quadriceps muscle is important for stability and optimal joint loading for both the tibiofemoral and the patellofemoral joint. The aim of this study was to examine whether the quadriceps femoris muscles are activated differently in open versus closed kinetic chain tasks. METHODS: Ten healthy men and women (mean age 28.5 +/- 0.7) extended the knees isometrically in open and closed kinetic chain tasks in a reaction time paradigm using moderate force. Surface electromyography (EMG) recordings were made from four different parts of the quadriceps muscle. The onset and amplitude of EMG and force data were measured. RESULTS: In closed chain knee extension, the onset of EMG activity of the four different muscle portions of the quadriceps was more simultaneous than in the open chain. In open chain, rectus femoris (RF) had the earliest EMG onset while vastus medialis obliquus was activated last (7 +/- 13 ms after RF EMG onset) and with smaller amplitude (40 +/- 30% of maximal voluntary contraction (MVC)) than in closed chain (46 +/- 43% MVC). CONCLUSIONS: Exercise in closed kinetic chain promotes more balanced initial quadriceps activation than does exercise in open kinetic chain. This may be of importance in designing training programs aimed toward control of the patellofemoral joint.

  • 15.
    Stensdotter, Ann-Katrin
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Hodges, Paul
    Öhberg, Fredrik
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Häger-Ross, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Quadriceps EMG in Open and Closed Kinetic Chain Tasks in Women With Patellofemoral Pain.2007In: Journal of motor behavior, ISSN 0022-2895, E-ISSN 1940-1027, Vol. 39, no 3, p. 194-202Article in journal (Refereed)
    Abstract [en]

    The authors investigated whether the discrepancy noted in the literature regarding delayed and decreased activity in vastus medialis obliquus (VMO) in people with patellofemoral pain (PFP) depends on the nature of the open kinetic chain (OKC) and the closed kinetic chain (CKC) in the experimental task. They hypothesized that activity in VMO would be more delayed and decreased in CKC tasks than in OKC tasks. Women with PFP (n = 17) and healthy controls (n = 17) performed isometric quadriceps contractions in CKC and OKC tasks. The authors manipulated only the application of resistance. Electromyographs (EMGs) showed that participants with PFP reacted later and activated the quadriceps more in the CKC task but had intramuscular quadriceps coordination similar to that of controls. The nature of the OKC task or the CKC task does not seem to explain contradictory findings regarding VMO activation.

  • 16.
    Stensdotter, Ann-Katrin
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Holmgren, Christer
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Diagnostic Radiology.
    Dalén, Tore
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Häger-Ross, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    The role of M. popliteus in unpredictable and in self-initiated balance provocations.2006In: Journal of Orthopaedic Research, ISSN 0736-0266, E-ISSN 1554-527X, Vol. 24, no 3, p. 524-530Article in journal (Refereed)
    Abstract [en]

    The purpose of this study was to determine whether m. popliteus (POP) activity would contribute to the control of knee joint position in unpredictable and in self-initiated provocations of standing balance. Ten healthy women (age 25.2 +/- 4.5 years, means and SD) without known knee pathology were tested for postural reactions (1) to unpredictable support surface translations in anterior and posterior directions, and (2) in self-initiated balance provocations in a reaction time (RT) forward reach-and-grip task. Electromyographic activity was recorded from POP and other leg muscles plus the deltoid muscle. Three-dimensional kinematics were captured for the knee joint and the body centre of mass was calculated. POP was active first of all the muscles recorded, regardless of translation direction, and knee joint movements elicited were either knee extension or external rotation of the tibia. In the RT task, the POP was active after initiation of reaching movement, and there was little consistency in the kinematic response. POP activity was not direction specific in response to support surface translation, but appeared triggered from reactive knee joint movement. The response to the support-surface translation suggests that POP served to control knee joint position rather than posture. In the RT task, we could not deduce whether POP activity was attributed to knee joint control or to postural control. Copyright 2006 Orthopaedic Research Society.

  • 17.
    Stensdotter, Ann-Katrin
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Department of Health Education and Social Work Physiotherapy, Sör-Trönderlag University College Trondheim.
    Tengman, Eva
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Brax Olofsson, Lisbeth
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Häger, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Deficits in single-limb stance more than 20 years after ACL injury2013In: European Journal of Physiotherapy, ISSN 2167-9169, E-ISSN 2167-9177, Vol. 15, no 2, p. 78-85Article in journal (Refereed)
    Abstract [en]

    Aim: To investigate the long-term effect on balance during single-limb stance after unilateral anterior cruciate ligament (ACL) injury across two groups who had rehabilitation including ACL reconstruction (ACLR) or a tailored physiotherapy program (ACLTPP), compared with knee-healthy controls.

    Methods: Single-limb stance was monitored for floor-supports with the contralateral foot. Single-limb stance without floor-supports was assessed with analyses of center of pressure (CoP) for further discrimination. Comparisons were made between ACLR (n = 28) and ACLTPP (n = 28) and with controls (n = 18). The injured and uninjured legs were compared within ACL-injured subjects.

    Results: Single-limb balance was equally inferior in both ACL-injured groups and on both legs compared with knee-healthy controls. In ACLR and ACLTPP, 39% and 50%, respectively, failed to stand on one leg without floor-supports with the contralateral foot. No contralateral supports occurred in knee-healthy controls. CoP measures for subjects who stood without contralateral floor-supports did not reveal any further differences. Older age and higher body mass index (BMI) correlated with larger migration of CoP.

    Conclusion: Inability to stand without contralateral supports showed that balance in single-limb stance was inferior in ACL-injured subjects, independently of which initial treatment that was given. Age and BMI need consideration in studies assessing balance in single-limb stance.

  • 18.
    Stensdotter, Ann-Katrin
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Faculty of Health and Social Sciences, Physiotherapy, Norwegian University of Science and Technology, NTNU, 7491 Trondheim, Norway.
    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.
    Altered postural control strategies in quiet standing more than 20 years after rupture of the anterior cruciate ligament2016In: Gait & Posture, ISSN 0966-6362, E-ISSN 1879-2219, Vol. 46, p. 98-103Article in journal (Refereed)
    Abstract [en]

    Aim: To explore long-term consequences of anterior cruciate ligament (ACL) rupture on postural sway and control strategies during bilateral quiet standing, in subjects treated with or without reconstructive surgery compared to uninjured controls. Method: 70 individuals who had unilateral ACL rupture 23 +/- 2.4 years ago (33 received ACL reconstructive surgery, ACL(R), and 37 had physiotherapy only, ACL(PT)) and 33 uninjured matched controls (CTRL) (mean age 46 +/- 5.3) stood quietly with eyes closed for 3 min on a firm and on a compliant surface, respectively. Center of pressure (CoP) was registered with a force plate and postural sway was calculated from center of mass (CoM) derived from 3D kinematics. Sway density (SD) analyses of CoP assessed distance and duration of stable phases. The torque controlling postural sway was estimated from CoP-CoM. Results: Comparisons across conditions to CTRL revealed larger CoP-CoM-area in ACLR (p = 0.017, Cl: 10.95, 143.10), but not in ACL(PT). Mean distance between SD-peaks was greater for ACLR (p < 0.001, Cl: 1.73, 5.31) than for ACLRT (p = 0.006, Cl: 0.56, 4.12) relative to CTRL. Duration of SD -peaks was smaller for both ACLR and ACLRT (p < 0.001, Cl: 4.04, 1.23 and 3.82, 1.03, respectively) compared to CTRL. CoM-area in the ACL-groups did not differ from CTRL. Conclusions: ACL-injured subjects demonstrated greater postural control efforts than CTRL but without significant differences in postural sway. Control efforts were thus not directly associated with sway and further research should be focused on variance in postural control strategies.

  • 19.
    Tengman, Eva
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Brax Olofsson, Lisbeth
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Stensdotter, Ann-Katrin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Sor-Trondelag University College, Trondheim, Norge.
    Nilsson, Kjell G
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Häger, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Anterior cruciate ligament injury after more than 20 years: II. Concentric and eccentric knee muscle strength2014In: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 24, no 6, p. e501-e509Article in journal (Refereed)
    Abstract [en]

    The long-term consequences on knee muscle strength some decades after rupture of the anterior cruciate ligament (ACL) are not established. The aims of our study were to examine peak torque more than 20 years after ACL injury and to compare their knee muscle strength to that of healthy controls. We tested 70 individuals with unilateral ACL injury 23 ± 2 years after injury, whereof 33 (21 men) were treated with physiotherapy in combination with ACL reconstruction (ACLR) and 37 (23 men) with physiotherapy alone (ACLPT). These were compared with 33 age- and gender-matched controls (21 men). A Kin-Com® dynamometer (90°/s) was used to measure peak torque in knee flexion and extension in both concentric and eccentric contractions. Knee extension peak torque, concentric and eccentric, was ∼10% lower for the injured leg compared with the non-injured leg for both ACLR (P < 0.001; P < 0.001) and ACLPT (P = 0.007; P = 0.002). The ACLPT group also showed reduced eccentric knee flexion torque of the injured leg (P = 0.008). The strength of the non-injured leg in both ACL groups was equal to that of controls. No difference was seen for those with no-or-low degree of knee osteoarthritis compared to those with moderate-to-high degree of osteoarthritis. ACL injury may lead to a persistent reduction of peak torque in the injured leg, which needs to be considered across the lifespan.

  • 20.
    Tengman, Eva
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Grip, Helena
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Stensdotter, Ann-Katrin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Sør-Trøndelag University College, Trondheim Norway.
    Häger, Charlotte
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    One-leg hop more than 20 years after ACL injury: kinematic analysis of persons treated with physiotherapy with or without surgery compared to healthy controlsManuscript (preprint) (Other academic)
  • 21.
    Tengman, Eva
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Grip, Helena
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Stensdotter, Ann-Katrin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. Faculty of Health Education and Social Work, Physiotherapy, Sør-Trøndelag University College, Trondheim, Norway.
    Häger, Charlotte K
    Anterior cruciate ligament injury about 20 years post-treatment: a kinematic analysis of one-leg hop2015In: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 25, no 6, p. 818-827Article in journal (Refereed)
    Abstract [en]

    Reduced dynamic knee stability, often evaluated with one-leg hops (OLHs), is reported after anterior cruciate ligament (ACL) injury. This may lead to long-standing altered movement patterns, which are less investigated. 3D kinematics during OLH were explored in 70 persons 23 +/- 2 years after ACL injury; 33 were treated with physiotherapy in combination with ACL reconstruction (ACL(R)) and 37 with physiotherapy alone (ACL(PT)). Comparisons were made to 33 matched controls. We analyzed (a) maximal knee joint angles and range of motion (flexion, abduction, rotation); (b) medio-lateral position of the center of mass (COM) in relation to knee and ankle joint centers, during take-off and landing phases. Unlike controls, ACL-injured displayed leg asymmetries: less knee flexion and less internal rotation at take-off and landing and more lateral COM related to knee and ankle joint of the injured leg at landing. Compared to controls, ACL(R) had larger external rotation of the injured leg at landing. ACL(PT) showed less knee flexion and larger external rotation at take-off and landing, and larger knee abduction at Landing. COM was more medial in relation to the knee at take-off and less laterally placed relative to the ankle at landing. ACL injury results in long-term kinematic alterations during OLH, which are less evident for ACL(R).

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