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Study Design: A factorial randomized controlled trial., Objectives: To investigate the addition of manual therapy to exercise therapy for the reduction of pain and increase of physical function in people with knee osteoarthritis (OA), and whether "booster sessions" compared to consecutive sessions may improve outcomes., Background: The benefits of providing manual therapy in addition to exercise therapy, or of distributing treatment sessions over time using periodic booster sessions, in people with knee OA are not well established., Methods: All participants had knee OA and were provided 12 sessions of multimodal exercise therapy supervised by a physical therapist. Participants were randomly allocated to 1 of 4 groups: exercise therapy in consecutive sessions, exercise therapy distributed over a year using booster sessions, exercise therapy plus manual therapy without booster sessions, and exercise therapy plus manual therapy with booster sessions. The primary outcome measure was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC score; 0-240 scale) at 1-year follow-up. Secondary outcome measures were the numeric pain-rating scale and physical performance tests., Results: Of 75 participants recruited, 66 (88%) were retained at 1-year follow-up. Factorial analysis of covariance of the main effects showed significant benefit from booster sessions (P = .009) and manual therapy (P = .023) over exercise therapy alone. Group analysis showed that exercise therapy with booster sessions (WOMAC score, -46.0 points; 95% confidence interval [CI]: -80.0, -12.0) and exercise therapy plus manual therapy (WOMAC score, -37.5 points; 95% CI: -69.7, -5.5) had superior effects compared with exercise therapy alone. The combined strategy of exercise therapy plus manual therapy with booster sessions was not superior to exercise therapy alone., Conclusion: Distributing 12 sessions of exercise therapy over a year in the form of booster sessions was more effective than providing 12 consecutive exercise therapy sessions. Providing manual therapy in addition to exercise therapy improved treatment effectiveness compared to providing 12 consecutive exercise therapy sessions alone. Trial registered with the Australian New Zealand Clinical Trials Registry (ACTRN12612000460808).

Patients with knee osteoarthritis often present with signs of mixed tibiofemoral and patellofemoral joint disease. It has been suggested that altered frontal and transverse plane knee joint mechanics play a key role in compartment-specific patterns of knee osteoarthritis, but in-vivo evidence in support of this premise remains limited. Using Dynamic Stereo X-ray techniques, the aim of this study was to compare the frontal and transverse plane tibiofemoral kinematics and patellofemoral malalignments during the loading response phase of downhill gait in three groups of older adults: patients with medial tibiofemoral compartment and coexisting patellofemoral osteoarthritis (n=11); patients with lateral tibiofemoral compartment and coexisting patellofemoral osteoarthritis (n=10); and an osteoarthritis-free control group (n=22). Patients with lateral compartment osteoarthritis walked with greater and increasing degrees of tibiofemoral abduction compared to the medial compartment osteoarthritis and the control groups who walked with increasing degrees of tibiofemoral adduction. Additionally, the medial and lateral compartment osteoarthritis groups demonstrated reduced degrees of tibiofemoral internal rotation compared to the control group. Both medial and lateral compartment osteoarthritis groups also walked with increasing degrees of lateral patella tilt and medial patella translation during the loading response phase of downhill gait. Our findings suggest that despite the differences in frontal and transverse plane tibiofemoral kinematics between patients with medial and lateral compartment osteoarthritis, the malalignments of their arthritic patellofemoral joint appears to be similar. Further research is needed to determine if these kinematic variations are relevant targets for interventions to reduce pain and disease progression in patients with mixed disease., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Knee osteoarthritis has been previously associated with a stereotypical knee-stiffening gait pattern and reduced knee joint motion variability due to increased antagonist muscle co-contractions and smaller utilized arc of motion during gait. However, episodic self-reported instability may be a sign of excessive motion variability for a large subgroup of patients with knee osteoarthritis. The objective of this work was to evaluate the differences in knee joint motion variability during gait in patients with knee osteoarthritis with and without self-reported instability compared to a control group of older adults with asymptomatic knees., Methods: Forty-three subjects, 8 with knee osteoarthritis but no reports of instability (stable), 11 with knee osteoarthritis and self-reported instability (unstable), and 24 without knee osteoarthritis or instability (control) underwent Dynamic Stereo X-ray analysis during a decline gait task on a treadmill. Knee motion variability was assessed using parametric phase plots during the loading response phase of decline gait., Findings: The stable group demonstrated decreased sagittal-plane motion variability compared to the control group (p=0.04), while the unstable group demonstrated increased sagittal-plane motion variability compared to the control (p=0.003) and stable groups (p<0.001). The unstable group also demonstrated increased anterior-posterior joint contact point motion variability for the medial tibiofemoral compartment compared to the control (p=0.03) and stable groups (p=0.03)., Interpretation: The finding of decreased knee motion variability in patients with knee osteoarthritis without self-reported instability supports previous research. However, presence of self-reported instability is associated with increased knee motion variability in patients with knee osteoarthritis and warrants further investigation., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Study Design: Experimental laboratory study., Objective: To characterize the differences in lower extremity gait biomechanics in individuals who have knee osteoarthritis (OA) with and without self-reported knee instability., Background: Individuals with knee OA who experience episodes of knee instability often report gait difficulties that interfere with their daily lives. A better understanding of the alterations in gait biomechanics may help to mitigate symptomatic knee instability in this patient population., Methods: Seventeen participants with knee OA and self-reported knee instability and 36 participants with knee OA and no self-reported knee instability underwent instrumented gait analysis on level ground. Knee-specific symptoms and functional limitations were assessed using the Western Ontario and McMaster Universities Osteoarthritis Index., Results: Knee instability was associated with greater odds of reporting moderate to severe gait-related pain (odds ratio = 6.0; 95% confidence interval: 1.2, 28.9) and moderate to severe difficulty when walking on flat surfaces (odds ratio = 10.7; 95% confidence interval: 1.7, 69.2). During early stance, the group with self-reported knee instability walked with a greater knee flexion excursion (P = .02) and a smaller lower extremity support moment (P<.01), due to reduced contributions from the hip extensors (P<.01) and ankle plantar flexors (P = .04). The group with self-reported knee instability also walked with a greater knee extensor contribution to the lower extremity support moment (P = .04) during the initial knee extension phase of gait compared to their counterparts with good knee stability., Conclusion: These findings suggest that self-reported knee instability is associated with significant alterations in hip, knee, and ankle joint function during the stance phase of gait in individuals with knee OA.

A Task Force of the Osteoarthritis Research Society International (OARSI) has previously published a set of guidelines for the conduct of clinical trials in osteoarthritis (OA) of the hip and knee. Limited material available on clinical trials of rehabilitation in people with OA has prompted OARSI to establish a separate Task Force to elaborate guidelines encompassing special issues relating to rehabilitation of OA. The Task Force identified three main categories of rehabilitation clinical trials. The categories included non-operative rehabilitation trials, post-operative rehabilitation trials, and trials examining the effectiveness of devices (e.g., assistive devices, bracing, physical agents, electrical stimulation, etc.) that are used in rehabilitation of people with OA. In addition, the Task Force identified two main categories of outcomes in rehabilitation clinical trials, which include outcomes related to symptoms and function, and outcomes related to disease modification. The guidelines for rehabilitation clinical trials provided in this report encompass these main categories. The report provides guidelines for conducting and reporting on randomized clinical trials. The topics include considerations for entering patients into trials, issues related to conducting trials, considerations for selecting outcome measures, and recommendations for statistical analyses and reporting of results. The focus of the report is on rehabilitation trials for hip, knee and hand OA, however, we believe the content is broad enough that it could be applied to rehabilitation trials for other regions as well., (Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

Osteoarthritis (OA) and type 2 diabetes mellitus (T2DM) often coexist in older adults. Those with T2DM are more susceptible to developing arthritis, which has been traditionally attributed to common risk factors, namely, age and obesity. Alterations in lipid metabolism and hyperglycemia might directly impact cartilage health and subchondral bone, contributing to the development/progression of OA. Adequate management of older persons with both conditions benefits from a comprehensive understanding of the associated risk factors. We discuss common risk factors and emerging links between OA and T2DM, emphasizing the importance of physical activity and the implications of safe and effective physical activity., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Coexisting patellofemoral osteoarthritis (PFOA) is a common finding in patients with tibiofemoral osteoarthritis (TFOA). The purpose of this study was to elucidate whether severity of coexisting PFOA in patients with TFOA is correlated with altered sagittal-plane gait biomechanics and greater knee-specific impairments. One hundred and six patients with radiographic TFOA were stratified into three groups of no PFOA, mild PFOA, and severe PFOA. All patients completed instrumented gait analysis, quantitative quadriceps strength testing and knee range of motion assessment. Compared to patients with no PFOA, those with severe PFOA exhibited reduced loading-response knee flexion excursions (p = 0.002) and increased peak single-leg stance external knee flexion moments (p < 0.05). The severe PFOA group also demonstrated lower quadriceps strength compared to the no PFOA and mild PFOA groups (p < 0.001). Regression analysis further revealed that quadriceps strength and knee extension range of motion were independently associated with altered sagittal-plane knee biomechanics during gait (p < 0.03). Reduced loading response knee flexion excursion during gait may be an attempt to decrease patellofemoral joint loading by patients with severe PFOA but it may increase impact loading of their arthritic tibiofemoral joint. Additionally, the greater external knee flexion moments observed during the single-leg stance phase of gait can lead to an overall increase in patellofemoral joint loading and symptoms in patients with more severe PFOA. Given the association between knee-specific impairments and altered gait biomechanics in our study, addressing quadriceps muscle weakness and limited knee extension range of motion may be indicated in patients with TFOA and severe coexisting PFOA., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Objective: This study aims to evaluate correlates of gait speed, a measure of disability, in older adults with advanced knee osteoarthritis (OA) and chronic pain., Design/setting/subjects/methods: Baseline data were analyzed from a clinical trial of 190 participants aged >50 with advanced knee OA (according to clinical and radiographic American College of Rheumatology criteria) and chronic pain. Data included 4-meter gait speed, quality of life (Short Form Health Survey 36 global health subscale), knee pain (Western Ontario and McMasters Universities Osteoarthritis Index [WOMAC]), depressive symptoms (Center for Epidemiologic Studies Depression Scale), coping strategies (catastrophizing subscale and Cognitive Strategies Questionnaire), self-efficacy (Athritis Self-efficacy Scale [ASES]), comorbidity (Cumulative Illness Rating Scale), analgesic use, and pain comorbidities (location, frequency, and intensity). A multivariable regression model was used to investigate these variables as they relate to gait speed., Results: In the univariate analysis, the following variables were associated with gait speed: knee pain (per WOMAC), age, depressive symptoms, global health, catastrophizing, ASES function and other, comorbidity, and opioid use (all P values <0.05). In the fully adjusted multivariate model, controlling for knee pain, significant associations between gait speed and age (β = -0.006; P < 0.001), ASES function (β = 0.003; P < 0.001), and opioid use (β = -0.082; P = 0.009) persisted. The correlation between opioid dose and gait speed (among opioid users) was not statistically significant (r = 0.04; P = 0.81)., Conclusion: In a cross-sectional study of older adults with advanced knee OA and chronic pain, we found that age, arthritis function self-efficacy, and opioid use (but not dose) were significantly associated with decreased gait speed., (Wiley Periodicals, Inc.)

Background: To evaluate knee joint contact mechanics and kinematics during the loading response phase of downhill gait in knee osteoarthritis patients with self-reported instability., Methods: Forty-three subjects, 11 with medial compartment knee osteoarthritis and self-reported instability (unstable), 7 with medial compartment knee osteoarthritis but no reports of instability (stable), and 25 without knee osteoarthritis or instability (control) underwent Dynamic Stereo X-ray analysis during a downhill gait task on a treadmill., Findings: The medial compartment contact point excursions were longer in the unstable group compared to the stable (P=0.046) and the control groups (P=0.016). The peak medial compartment contact point velocity was also greater for the unstable group compared to the stable (P=0.047) and control groups (P=0.022). Additionally, the unstable group demonstrated a coupled movement pattern of knee extension and external rotation after heel contact which was different than the coupled motion of knee flexion and internal rotation demonstrated by stable and control groups., Interpretation: Our findings suggest that knee joint contact mechanics and kinematics are altered during the loading response phase of downhill gait in knee osteoarthritis patients with self-reported instability. The observed longer medial compartment contact point excursions and higher velocities represent objective signs of mechanical instability that may place the arthritic knee joint at increased risk for disease progression. Further research is indicated to explore the clinical relevance of altered contact mechanics and kinematics during other common daily activities and to assess the efficacy of rehabilitation programs to improve altered joint biomechanics in knee osteoarthritis patients with self-reported instability., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Obesity is a well-known modifiable risk factor for osteoarthritis (OA) in weight-bearing joints, and is present in approximately 35% of individuals with OA. Obesity adds significant burden to individuals with OA and is associated with poorer functional status and greater disability. In addition to tackling OA-related impairments, such as pain and functional limitations, interventions in this population need to address bodyweight reduction, as well as promotion of active lifestyle behaviors. While exercise and regular physical activity participation are both recommended and beneficial for OA and obese populations, our current understanding of optimal strategies to improve function and health status in those who have both OA and obesity is limited. This review will summarize the current available evidence related to effectiveness of various physical activity interventions to reduce pain, improve function and overall health-related quality of life in overweight or obese individuals with OA.

Synopsis: Altered knee joint biomechanics and excessive joint loading have long been considered as important contributors to the development and progression of knee osteoarthritis. Therefore, a better understanding of how various treatment options influence the loading environment of the knee joint could have practical implications for devising more effective physical therapy management strategies. The aim of this clinical commentary was to review the pertinent biomechanical evidence supporting the use of treatment options intended to provide protection against excessive joint loading while offering symptomatic relief and functional improvements for better long-term management of patients with knee osteoarthritis. The biomechanical and clinical evidence regarding the effectiveness of knee joint offloading strategies, including contralateral cane use, laterally wedged shoe insoles, variable-stiffness shoes, valgus knee bracing, and gait-modification strategies, within the context of effective disease management is discussed. In addition, the potential role of therapeutic exercise and neuromuscular training to improve the mechanical environment of the knee joint is considered. Management strategies for treatment of joint instability and patellofemoral compartment disease are also mentioned. Based on the evidence presented as part of this clinical commentary, it is argued that special considerations for the role of knee joint biomechanics and excessive joint loading are necessary in designing effective short- and long-term management strategies for treatment of patients with knee osteoarthritis., Level of Evidence: Therapy, level 5.

Objective: To evaluate the association between severity of coexisting patellofemoral (PF) disease with lower extremity impairments and functional limitations in patients with tibiofemoral (TF) osteoarthritis (OA)., Methods: Radiographic views of the TF and PF compartments, knee extension strength, and knee range of motion were obtained for 167 patients with knee OA. Additionally, knee-specific symptoms and functional limitations were assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Activities of Daily Living Scale (ADLS)., Results: Moderate/severe PFOA was associated with lower knee extension strength (mean ± SD 1.4 ± 0.5 Nm/body weight [BW]) compared to no PFOA (mean ± SD 1.8 ± 0.5 Nm/BW). Additionally, total knee range of motion was significantly lower for patients with moderate/severe PFOA (mean ± SD 120.8° ± 14.4°) compared to no PFOA (mean ± SD 133.5° ± 10.7°) and mild PFOA (mean ± SD 125.8° ± 13.0°). Moderate/severe PFOA and mild PFOA were also associated with less pain while standing (odds ratio [OR] 0.2, 95% confidence interval [95% CI] 0.1-0.7 and OR 0.2, 95% CI 0.1-0.6, respectively) on the WOMAC, and moderate/severe PFOA was associated with greater difficulty with going downstairs (OR 2.9, 95% CI 1.0-8.1) on the ADLS., Conclusion: It appears that knees with more severe coexisting PF disease demonstrate features distinct from those observed in TFOA in isolation or in combination with mild PF disease. Treatment strategies targeting the PF joint may be warranted to mitigate the specific lower extremity impairments and functional problems present in this patient population., (Copyright © 2013 by the American College of Rheumatology.)

Cellular therapy is a potential approach to improve the regenerative capacity of damaged or diseased skeletal muscle. However, its clinical use has often been limited by impaired donor cell survival, proliferation and differentiation following transplantation. Additionally, functional improvements after transplantation are all-too-often negligible. Because the host microenvironment plays an important role in the fate of transplanted cells, methods to modulate the microenvironment and guide donor cell behavior are warranted. The purpose of this study was to investigate whether the use of neuromuscular electrical stimulation (NMES) for 1 or 4 weeks following muscle-derived stem cell (MDSC) transplantation into dystrophic skeletal muscle can modulate the fate of donor cells and enhance their contribution to muscle regeneration and functional improvements. Animals submitted to 4 weeks of NMES after transplantation demonstrated a 2-fold increase in the number of dystrophin+ myofibers as compared to control transplanted muscles. These findings were concomitant with an increased vascularity in the MDSC+NMES group when compared to non-stimulated counterparts. Additionally, animals subjected to NMES (with or without MDSC transplantation) presented an increased maximal specific tetanic force when compared to controls. Although cell transplantation and/or the use of NMES resulted in no changes in fatigue resistance, the combination of both MDSC transplantation and NMES resulted in a faster recovery from fatigue, when compared to non-injected and non-stimulated counterparts. We conclude that NMES is a viable method to improve MDSC engraftment, enhance dystrophic muscle strength, and, in combination with MDSC transplantation, improve recovery from fatigue. These findings suggest that NMES may be a clinically-relevant adjunct approach for cell transplantation into skeletal muscle.

Background: The therapeutic effect of neuromuscular electrical stimulation (NMES) on muscle strengthening and hypertrophy depends on its dose. Patients must tolerate high doses of NMES to maximize gains in muscle function. It is unknown why some patients are able to achieve high NMES dose while others are not. Disability and psychological attributes may play a role in a patient's tolerance of NMES dose., Purpose: To explore if disability and psychological attributes associate with the ability to achieve high doses of NMES in patients with rheumatoid arthritis (RA)., Methods: Cross-sectional study. Forty subjects with RA participated in 2 sessions of NMES intervention to the quadriceps muscles. The highest NMES dose achieved by each subject was recorded. Dose was defined as the torque produced by the NMES as a percentage of the torque produced during a maximum voluntary isometric contraction. Subjects were then grouped in high or low NMES dose. Variables investigated in this study included disability, pain coping strategies, pain acceptance, sense of mastery or control, anxiety, and depression. Correlations were sought between these factors and NMES dose., Main Results: In unadjusted models, disability, coping self-statements, catastrophizing, and anxiety were predictors of NMES dose. In adjusted models only disability (OR = 0.17 [95% CI: 0.04, 0.77]) and catastrophizing (OR = 0.85 [95% CI: 0.72, 0.99]) predicted NMES dose., Conclusion: Patients with RA with lower disability and lower catastrophising achieve higher doses of NMES. Identifying factors associated with achieving high NMES dose may guide strategies to improve effectiveness of this intervention.

Objective: Understanding how changes in physical and psychological factors following therapeutic exercise are associated with treatment outcome could have important implications for refining rehabilitation programs for knee osteoarthritis (OA). The objective of this study was to examine the association of changes in these factors with changes in pain and function after an exercise program for people with knee OA., Methods: In total, 152 people with knee OA completed an exercise program consisting of lower extremity strengthening, stretching, range of motion, balance and agility, and aerobic exercises. The change from baseline to the 2-month followup was calculated for physical and psychological factors, including self-reported knee instability, quadriceps strength, knee and ankle range of motion, lower extremity muscle flexibility, fear of physical activity, anxiety, and depressive symptoms. Treatment response was defined as a minimum of a 20% improvement from baseline in both a numerical knee pain rating scale and the Western Ontario and McMaster Universities Osteoarthritis Index physical function scale. The association of each factor with treatment response was examined with logistic regression mutually adjusted for age, sex, body mass index, radiographic severity, and exercise group., Results: Change in self-reported knee instability (odds ratio [OR] 1.67 [95% confidence interval (95% CI) 1.13-2.47]) and fear of physical activity (OR 0.93 [95% CI 0.88-1.00]) were the only 2 factors that were significantly associated with treatment response after adjustment for covariates., Conclusion: Improvement in knee instability and fear of physical activity were associated with increased odds of a positive treatment response following therapeutic exercise in subjects with knee OA., (Copyright © 2012 by the American College of Rheumatology.)

Study Design: Secondary analysis, pretreatment-posttreatment observational study., Objective: To compare the reliability and responsiveness of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Knee Outcome Survey activities of daily living subscale (KOS-ADL), and the Lower Extremity Functional Scale (LEFS) in individuals with knee osteoarthritis (OA)., Background: The WOMAC is the current standard in patient-reported measures of function in patients with knee OA. The KOS-ADL and LEFS were designed for potential use in patients with knee OA. If the KOS-ADL and LEFS are to be considered viable alternatives to the WOMAC for measuring patient-reported function in individuals with knee OA, they should have measurement properties comparable to the WOMAC. It would also be important to determine whether either of these instruments may be superior to the WOMAC in terms of reliability or responsiveness in this population., Methods: Data from 168 subjects with knee OA, who participated in a rehabilitation program, were used in the analyses. Reliability and responsiveness of each outcome measure were estimated at follow-ups of 2, 6, and 12 months. Reliability was estimated by calculating the intraclass correlation coefficient (ICC2,1) for subjects who were unchanged in status from baseline at each follow-up time, based on a global rating of change score. To examine responsiveness, the standard error of the measurement, minimal detectable change, minimal clinically important difference, and the Guyatt responsiveness index were calculated for each outcome measure at each follow-up time., Results: All 3 outcome measures demonstrated reasonable reliability and responsiveness to change. Reliability and responsiveness tended to decrease somewhat with increasing follow-up time. There were no substantial differences between outcome measures for reliability or any of the 3 measures of responsiveness at any follow-up time., Conclusion: The results do not indicate that one outcome measure is more reliable or responsive than another when applied to subjects with knee OA. We believe that all 3 instruments are appropriate outcome measures to examine change in functional status of patients with knee OA.

Neuromuscular electrical stimulation (NMES) is a common clinical modality that is widely used to restore (1), maintain (2) or enhance (3-5) muscle functional capacity. Transcutaneous surface stimulation of skeletal muscle involves a current flow between a cathode and an anode, thereby inducing excitement of the motor unit and the surrounding muscle fibers. NMES is an attractive modality to evaluate skeletal muscle adaptive responses for several reasons. First, it provides a reproducible experimental model in which physiological adaptations, such as myofiber hypertophy and muscle strengthening (6), angiogenesis (7-9), growth factor secretion (9-11), and muscle precursor cell activation (12) are well documented. Such physiological responses may be carefully titrated using different parameters of stimulation (for Cochrane review, see (13)). In addition, NMES recruits motor units non-selectively, and in a spatially fixed and temporally synchronous manner (14), offering the advantage of exerting a treatment effect on all fibers, regardless of fiber type. Although there are specified contraindications to NMES in clinical populations, including peripheral venous disorders or malignancy, for example, NMES is safe and feasible, even for those who are ill and/or bedridden and for populations in which rigorous exercise may be challenging. Here, we demonstrate the protocol for adapting commercially available electrodes and performing a NMES protocol using a murine model. This animal model has the advantage of utilizing a clinically available device and providing instant feedback regarding positioning of the electrode to elicit the desired muscle contractile effect. For the purpose of this manuscript, we will describe the protocol for muscle stimulation of the anterior compartment muscles of a mouse hindlimb.

Background: Joint instability has been suggested as a risk factor for knee osteoarthritis and a cause of significant functional decline in those with symptomatic disease. However, the relationship between altered knee joint mechanics and self-reports of instability in individuals with knee osteoarthritis remains unclear., Methods: Fourteen subjects with knee osteoarthritis and complaints of joint instability and 12 control volunteers with no history of knee disease were recruited for this study. Dynamic stereo X-ray technology was used to assess the three-dimensional kinematics of the knee joint during the loading response phase of gait., Findings: Individuals with concurrent knee osteoarthritis and joint instability demonstrated significantly reduced flexion and internal/external rotation knee motion excursions during the loading response phase of gait (P<0.01), while the total abduction/adduction range of motion was increased (P<0.05). In addition, the coronal and transverse plane alignment of the knee joint at initial contact was significantly different (P<0.05) for individuals with concurrent knee osteoarthritis and joint instability. However, the anteroposterior and mediolateral tibiofemoral joint positions at initial contact and the corresponding total joint translations were similar between groups during the loading phase of gait., Interpretations: The rotational patterns of tibiofemoral joint motion and joint alignments reported for individuals with concurrent knee osteoarthritis and joint instability are consistent with those previously established for individuals with knee osteoarthritis. Furthermore, the findings of similar translatory tibiofemoral motion between groups suggest that self-reports of episodic joint instability in individuals with knee osteoarthritis may not necessarily be associated with adaptive alterations in joint arthrokinematics., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Background: Little is known regarding how impairment-based exercises may improve performance of specific functional tasks in people with knee osteoarthritis (OA)., Objective: The purpose of this study was to compare the probability that participation in an impairment-based exercise program or the same impairment-based program supplemented with agility and perturbation training will improve patient-reported function on specific functional tasks., Design: This study was a secondary analysis of data from a randomized clinical trial., Setting: The study was conducted in the outpatient physical therapy clinic of a large, university-based health center., Participants: One hundred eighty-three people with knee OA (122 women, 61 men) participated., Interventions: Participants were randomly assigned to either a group that received agility and perturbation training with standard exercise therapy or a group that received only the standard exercise., Measurements: Specific functional items were taken from the physical function subscale of the Western Ontario and McMasters Universities Osteoarthritis Index, the Lower Extremity Function Scale, and the Activities of Daily Living Scale of the Knee Outcome Survey., Results: The probability of self-reported improvement in a variety of specific functional tasks was low following participation in either of the exercise programs. When only participants with moderate to severe difficulty performing specific functional tasks were considered in the analysis, the probability of success improved but was still limited., Limitations: The results are generalizable only to self-reported assessment of performance of specific functional tasks., Conclusions: Impairment-based exercise may not be enough to make substantial improvement in performance of specific functional tasks. Task-specific exercise approaches need to be explored for people with knee OA.

Study Design: Prospective cohort study., Objectives: To characterize knee cartilage change in individuals with knee osteoarthritis (KOA) who have completed a therapeutic exercise program., Background: While therapeutic exercise is frequently used successfully to improve pain and function in individuals with KOA, no studies have reported the volume of cartilage change or individual factors that may impact volume of cartilage change in those completing an exercise program for KOA., Methods: Thirteen individuals with KOA underwent magnetic resonance imaging to quantify cartilage volume change in the weight-bearing regions of the medial and lateral femoral condyles and the entire surface of the tibial plateaus from baseline to 1-year follow-up. Body structure and function measures were taken for body mass index, knee axis alignment, knee motion, and knee strength. Activity limitations and activity levels were also measured prior to the therapeutic exercise program, using the Western Ontario and McMaster Universities Osteoarthritis Index and the Physical Activity Scale for the Elderly. At 6 months from baseline, follow-up clinical measurements of knee strength and motion were performed. At 1 year from baseline, imaging of the knee cartilage and knee alignment were performed, and participants completed the Western Ontario and McMaster Universities Osteoarthritis Index and Physical Activity Scale for the Elderly., Results: The central region of the medial femoral condyle (cMF) had a median volume of cartilage loss of 3.8%. The other 3 knee tibiofemoral articular surfaces had minimal median cartilage volume change. Individuals were dichotomized into progressors (n = 6) and nonprogressors (n = 7), based on the standard error of measurement of cartilage volume change for the cMF. Progressors were younger, had a larger body mass index, had a higher Kellgren-Lawrence grade in the medial compartment of the knee, and had a greater increase in knee varus alignment from baseline to 1-year follow-up. The progressors also had frontal plane hip and knee kinetics during baseline gait analysis that potentially increased medial knee joint loading., Conclusion: The loss of cMF cartilage volume was highly variable and the median loss of cartilage was within the range previously reported. Seven of the 13 individuals did not have cMF cartilage volume loss greater than the standard error of measurement. Change in cartilage volume of the cMF may be influenced to a greater extent by personal factors than by completion of a therapeutic exercise program. Additional research is needed to decipher the interactions among therapeutic exercise and personal characteristics that impact knee cartilage loss.

Objective: We determined whether baseline depressive symptoms, knee-related confidence and general psychological distress influenced changes in pain and function during 2 years of follow-up., Design: We included persons in the Osteoarthritis Initiative (OAI) dataset with baseline pain of 1 or greater on a 0-10 scale in at least one knee and no knee or hip surgery during the 2-year follow-up (n=3407). The four outcome variables were repeated chair standing, 20 m walk and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain and Disability. Linear mixed effects models assessed the association of each mental health variable with the yearly change in each baseline adjusted outcome measure after controlling for covariates., Results: Depressive symptoms were significantly predictive of worsening in most outcomes. The magnitude of worsening predicted for each year was small. For example, the dichotomized WOMAC Pain model indicated that depressed persons experience more rapid worsening than non-depressed persons at an average rate of 0.59 WOMAC points per year (95% CI 0.176, 1.013, P=0.005). Similar significant but very small effects of depressive symptoms on other outcomes were observed. Knee confidence was not predictive of change. General psychological distress was predictive of change in 20-m walk and WOMAC Pain., Conclusions: The most consistent psychological predictor of yearly worsening was baseline depressive symptoms. Although a statistically robust predictor of outcome, given that change was very small and highly dependent on baseline status, our results indicate that a considerable degree of persistent depressive symptoms would be required to have a meaningful effect on future self-reported outcome., (Copyright © 2011 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

Background: Impairment-based exercise programs have yielded only small to moderate benefits in reducing pain and improving function in people with knee osteoarthritis (OA). It has previously been proposed that adding agility and perturbation training to exercise programs for people with knee OA may improve treatment effects for pain and function., Objective: The purpose of this study was to examine the effectiveness of adding agility and perturbation techniques to standard exercise therapy compared with the standard exercise program alone for people with knee OA., Design: This was a single-blinded randomized controlled trial., Setting: The study was conducted in the outpatient physical therapy clinic of a large, university-based health center., Participants: One hundred eighty-three people with knee OA (122 women, 61 men) participated., Interventions: Participants were randomly assigned to either a group that received agility and perturbation training with standard exercise therapy or a group that received only the standard exercise program., Measurements: The outcome measures were self-reported knee pain and function, self-reported knee instability, a performance-based measure of function, and global rating of change., Results: Although both groups exhibited improvement in self-reported function and in the global rating of change at the 2-, 6-, and 12-month follow-up periods, there were no differences between groups on these outcomes. There was no reduction in knee pain or improvement in performance-based function in either group., Limitations: It is possible that more-intense application of the interventions or application of the interventions to participants with knee OA who were at greater risk for falling may have yielded additive effects of the agility and perturbation training approach., Conclusions: Both intervention groups exhibited improvement in self-reported function and the global rating of change. Our results, however, did not support an additive effect of agility and perturbation training with standard exercise therapy in our sample of individuals with knee OA. Further study is needed to determine whether there are subgroups of individuals who might achieve an added benefit with this approach.

Background: Investigating modifiable factors that contribute to functional limitations in patients with total knee arthroplasty (TKA) may guide changes in rehabilitation protocols and improve functional outcomes. Whereas quadriceps muscle weakness has been demonstrated to contribute to functional limitations in TKA, the role of hip abductor weakness has not received attention., Objective: The purpose of this study was to determine whether hip abductor strength (force-generating capacity) contributes to physical function beyond what can be explained by quadriceps muscle strength in patients after a TKA., Design: A cross-sectional design was used in the study., Setting: The study was conducted in a clinical laboratory at an academic center., Patients: Thirty-one people with TKA (74% female; mean age=68 years, SD=8; mean body mass index=31 kg/m(2), SD=5) participated in the study., Measurements: Strength of quadriceps muscles and hip abductors was measured using an isokinetic dynamometer. Performance-based physical function was assessed with 4 measures: self-selected walking speed, the Figure-of-8 Walk Test, the Stair Ascend/Descend Test, and the 5-Chair Rise Test. Self-reported physical function was assessed with the Western Ontario and McMaster Universities Osteoarthritis Index Physical Function Subscale., Results: In hierarchical regression models, after accounting for demographic and anthropometric factors, quadriceps muscle strength was associated with performance on the Stair Ascend/Descend Test. After accounting for demographic, anthropometric, and quadriceps strength, hip abductor strength was associated with performance on the Stair Ascend/Descend Test, the Figure-of-8 Walk Test, and the 5-Chair Rise Test., Limitations: The study design precluded ascertainment of causal relationships., Conclusions: After TKA, hip abductor strength influenced physical function in participants more than did demographic or anthropometric measures or quadriceps strength. Longitudinal studies with larger samples are warranted. If findings are replicated, they will justify targeting the hip abductors during rehabilitation after TKA.

Dramatic changes in the health care landscape over the next few decades undoubtedly will affect rehabilitation specialists' practice. In the multidisciplinary field of regenerative medicine, cell, tissue, or organ substitutes are used to enhance the healing potential of the body. Given that the restoration of normal functioning of injured or diseased tissues is expected to be the ultimate goal of these therapies, the future of regenerative medicine is, undeniably, tightly intertwined with that of rehabilitation. Rehabilitation specialists not only must be aware of cutting-edge medical advances as they relate to regenerative medicine but also must work closely with basic scientists to guide the development of clinically relevant protocols. The purposes of this article are to provide a current perspective on biological approaches to the management of musculoskeletal disorders and to highlight the needed integration of physical therapeutics with regenerative medicine.

Background and Purpose: The impact of cancer and its treatments on balance and functional mobility in older adults remains unknown but is increasingly important, given the evolution of cancer treatments. Subacute and more persistent side effects such as chemotherapy-induced peripheral neuropathy are on the rise, and the effects on mobility and balance, as well as the prognosis for resolution of any functional deficits, must be established before interventions can be trialed. The purpose of this case report is to describe the severity and long-term persistence of mobility decline in an older adult who received neurotoxic chemotherapy. To our knowledge, this is the first case report to describe an older adult with chemotherapy-induced peripheral neuropathy using results of standardized balance and mobility tests and to focus on prognosis by repeating these measures more than 2 years after chemotherapy., Case Description: An 81-year-old woman received a neurotoxic agent (paclitaxel) after curative mastectomy for breast cancer. Baseline testing prior to taxane therapy revealed a socially active woman with no reported functional deficits or neuropathic symptoms, 1.2-m/s gait speed, and performance at the ceiling on balance and gait portions of a standardized mobility measure., Outcomes: After 3 cycles, paclitaxel therapy was stopped by the oncologist because of neurotoxicity. Declines as large as 50% were seen in performance-based measures at 12 weeks and persisted at 2.5 years, and the patient reported recurrent falls, cane use, and mobility-related disability., Discussion: This case highlights the extent to which function can decline in an older individual receiving neurotoxic chemotherapy, the potential for these deficits to persist years after treatment is stopped, and the need for physical therapy intervention and further research in this population.

Background: Patients with total knee arthroplasty (TKA) have impaired balance and movement control. Exercise interventions have not targeted these impairments in this population., Objectives: The purposes of this study were: (1) to determine the feasibility of applying a balance exercise program in patients with TKA, (2) to investigate whether a functional training (FT) program supplemented with a balance exercise program (FT+B program) could improve physical function compared with an FT program alone in a small group of individuals with TKA, and (3) to test the methods and calculate sample size for a future randomized trial with a larger study sample., Design: This study was a double-blind, pilot randomized clinical trial., Setting: The study was conducted in the clinical laboratory of an academic center., Participants: The participants were 43 individuals (30 female, 13 male; mean age=68 years, SD=8) who underwent TKA 2 to 6 months prior to the study., Interventions: The interventions were 6 weeks (12 sessions) of a supervised FT or FT+B program, followed by a 4-month home exercise program., Measurements: Feasibility measures included pain, stiffness, adherence, and attrition. The primary outcome measure was a battery of physical performance tests: self-selected gait speed, chair rise test, and single-leg stance time. Secondary outcome measures were the Western Ontario and McMaster Universities Osteoarthritis Index and the Lower Extremity Functional Scale., Results: Feasibility of the balance training in people with TKA was supported by high exercise adherence, a relatively low dropout rate, and no adverse events. Both groups demonstrated clinically important improvements in lower-extremity functional status. The degree of improvement seemed higher for gait speed, single-leg stance time, and stiffness in the FT+B group compared with the FT group., Limitations: Due to the pilot nature of the study, differences between groups did not have adequate power to show statistical significance., Conclusions: There is a need for conducting a larger randomized controlled trial to test the effectiveness of an FT+B program after TKA.

Objective: (1) To determine the interrater reliability and measurement error of an 11-step stair ascend/descend test (STTotal-11) and stair up (ascend) test (STUp-11); (2) to seek evidence for the STTotal-11 and STUp-11 as valid measures of physical function by determining if they relate to measures of physical function and do not relate to measures not of physical function; and (3) to explore if the STTotal-11 and STUp-11 scores relate to lower-extremity muscle weakness and knee range of motion (ROM) in subjects with total knee arthroplasty (TKA)., Design: Cross-sectional study., Setting: Academic center., Participants: Subjects (N=43, 30 women; mean age, 68+/-8y) with unilateral TKA., Interventions: Not applicable., Main Outcome Measures: STTotal-11 and STUp-11 were performed twice, and scores were compared with scores on 4 lower extremity performance-based tasks, 2 patient-reported questionnaires of physical function, 3 psychologic factors, knee ROM, and strength of quadriceps, hip extensors, and abductors., Results: Intraclass correlation coefficient was .94 for both the STTotal-11 and STUp-11, standard error of measurements were 1.14 seconds and .82 seconds, and minimum detectable change associated with 90% confidence interval was 2.6 seconds and 1.9 seconds, respectively. Correlations between stair tests and performance-based measures and knee and hip muscle strength ranged from Pearson correlation coefficient (r)=.40 to .78. STTotal-11 and STUp-11 had a small correlation with one of the patient-reported measures of physical function. Stair tests were not associated with psychologic factors and knee extension ROM and were associated with knee flexion ROM., Conclusions: STTotal-11 and STUp-11 have good interrater reliability and minimum detectable changes adequate for clinical use. The pattern of associations supports the validity of the stair tests in TKA., (Copyright 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

Muscle-derived stem-cell (MDSC) transplantation presents a promising method for the treatment of muscle injuries. This study investigated the ability of exercise to enhance MDSC transplantation into the injured muscle. Mice were divided into four groups: contusion + phosphate-buffered saline (C + PBS; n = 14 muscles), C + MDSC transplantation (n = 12 muscles), C + PBS + treadmill running (C + PBS + TM; n = 17 muscles), and C + MDSC + TM (n = 13 muscles). One day after injury, the TM groups began running for 1 or 5 weeks. Two days after injury, muscles of C + MDSC and C + MDSC + TM groups were injected with MDSCs. One or 5 weeks later, the number and differentiation of transplanted MDSCs, myofiber regeneration, collagen I formation, and vascularity were assessed histologically. In vitro, MDSCs were subjected to mechanical stimulation, and growth kinetics were quantified. In vitro, mechanical stimulation decreased the MDSC population doubling time (18.6 +/- 1.6 h) and cell division time (10.9 +/- 0.7 h), compared with the controls (population doubling time: 23.0 +/- 3.4 h; cell division time: 13.3 +/- 1.1 h) (p = 0.01 and 0.03, respectively). In vivo, 5 weeks of TM increased the myogenic contribution of transplanted MDSCs, compared with the controls (p = 0.02). C + MDSC, C + PBS + TM, and C + MDSC + TM demonstrated decreased fibrosis at 5 weeks, compared with the C + PBS controls (p = 0.00, p = 0.03, and p = 0.02, respectively). Results suggest that the mechanical stimulation favors MDSC proliferation, both in vitro and in vivo, and that exercise enhances MDSC transplantation after injury.

Objectives: To explore whether the psychologic variables anxiety, depression, and fear-avoidance beliefs, and interactions between these variables, are associated with physical function in patients with knee osteoarthritis (OA). We hypothesized lower levels of function would be related to higher anxiety, higher depression, and higher fear-avoidance beliefs, and that high levels of 2 of these factors simultaneously might interact to have a greater adverse effect on physical function., Design: Cross-sectional, correlational design., Setting: Institutional practice., Participants: Subjects included patients with knee OA (N=182; age, mean +/- SD, 63.9+/-8.8y; 122 women)., Interventions: Not applicable., Main Outcome Measures: Self-report measures of function included the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index, the Lower Extremity Function Scale (LEFS), and the Knee Outcome Survey-Activity of Daily Living Scale. The Get Up and Go test was used as a physical performance measure of function. Self-report measures for psychologic variables included the Beck Anxiety Inventory, the Center for Epidemiological Studies Depression Scale, and the Fear Avoidance Belief Questionnaire-Physical Activity Scale modified for the knee., Results: Higher anxiety was related to poorer function on the WOMAC physical function. Both high anxiety and fear-avoidance beliefs were related to poorer function on the LEFS and Knee Outcome Survey-Activity of Daily Living Scale. There was no association between the psychologic variables and the Get Up and Go test. The anxiety x depression interaction was associated with the LEFS., Conclusions: Anxiety and fear-avoidance beliefs are associated with self-report measures of function in patients with knee OA. Depression may influence scores on the LEFS under conditions of low anxiety.

Objectives: To explore whether impairment of muscle strength, soft tissue length, movement control, postural and biomechanic alterations, and psychologic factors are associated with physical function and pain in patients with patellofemoral pain syndrome (PFPS)., Design: Cross-sectional study., Setting: Rehabilitation outpatient., Participants: Seventy-four patients diagnosed with PFPS., Interventions: Not applicable., Main Outcome Measures: Measurements were self-reported function and pain; strength of quadriceps, hip abduction, and hip external rotation; length of hamstrings, quadriceps, plantar flexors, iliotibial band/tensor fasciae latae complex, and lateral retinaculum; foot pronation; Q-angle; tibial torsion; visual observation of quality of movement during a lateral step-down task; anxiety; and fear-avoidance beliefs., Results: After controlling for age and sex, anxiety and fear-avoidance beliefs about work and physical activity were associated with function, while only fear-avoidance beliefs about work and physical activity were associated with pain., Conclusions: Psychologic factors were the only associates of function and pain in patients with PFPS. Factors related to physical impairments did not associate to function or pain. Our results should be validated in other samples of patients with PFPS. Further studies should determine the role of other psychologic factors, and how they relate to anxiety and fear-avoidance beliefs in these patients.

Objectives: To evaluate the effect of functional overloading on the transplantation of muscle derived stem cells (MDSCs) into dystrophic muscle and the ability of transplanted cells to increase dystrophic muscle's ability to resist overloading-induced weakness., Design: Cross-sectional., Setting: Laboratory., Animals: Male mice (N=10) with a dystrophin gene mutation., Interventions: MDSCs were intramuscularly transplanted into the extensor digitorum longus muscle (EDL). Functional overloading of the EDL was performed by surgical ablation of the EDL's synergist., Main Outcome Measures: The total number of dystrophin-positive fibers/cross-section (as a measure of stem cell engraftment), the average number of CD31+ cells (as a measure of capillarity), and in vitro EDL contractile strength. Independent t tests were used to investigate the effect of overloading on engraftment, capillarity, and strength. Paired t tests were used to investigate the effect of MDSC engraftment on strength and capillarity., Results: MDSC transplantation protects dystrophic muscles against overloading-induced weakness (specific twitch force: control 4.5N/cm2+/-2.3; MDSC treated 7.9N/cm2+/-1.4) (P=.02). This improved force production following overloading is concomitant with an increased regeneration by transplanted MDSCs (MDSC: 26.6+/-20.2 dystrophin-positive fibers/cross-section; overloading + MDSC: 170.6+/-130.9 dystrophin-positive fibers/cross-section [P=.03]). Overloading-induced increases in skeletal muscle capillarity is significantly correlated with increased MDSC engraftment (R2=.80, P=.01)., Conclusions: These findings suggest that the functional contribution of transplanted MDSCs may rely on activity-dependent mechanisms, possibly mediated by skeletal muscle vascularity. Rehabilitation modalities may play an important role in the development of stem cell transplantation strategies for the treatment of muscular dystrophy.

Background and Purpose: Studies have identified factors that contribute to functional limitations in people with knee osteoarthritis (OA), including quadriceps femoris muscle weakness, joint laxity, and reports of knee instability. However, little is known about the relationship among these factors or their relative influence on function. The purpose of this study was to investigate self-reported knee instability and its relationships with knee laxity and function in people with medial knee osteoarthritis (OA)., Participants: Fifty-two individuals with medial knee OA participated in the study., Methods: Each participant was classified into 1 of 3 groups based on reports of knee instability. Limb alignment, knee laxity, and quadriceps femoris muscle strength (force-generating capacity) were assessed. Function was measured with the Knee Injury and Osteoarthritis Outcome Score (KOOS) and a stair-climbing test (SCT). Group differences were detected with one-way analyses of variance, and relationships among variables were assessed with the Eta(2) statistic and hierarchical regression analysis., Results: There were no differences in alignment, laxity, or strength among the 3 groups. Self-reported knee instability did not correlate with medial laxity, limb alignment, or quadriceps femoris muscle strength. Individuals reporting worse knee instability scored worse on all subsets of the KOOS. Self-reported knee instability scores significantly contributed to the prediction of all measures of function above that explained by quadriceps femoris muscle force, knee laxity, and alignment. Neither laxity nor alignment contributed to any measure of function., Discussion and Conclusion: Self-reported knee instability is a factor that is not directly associated with knee laxity and contributes to worse function. Further research is necessary to delineate the factors that contribute to self-reported knee instability and reduced function in this population.

Background and Purpose: Muscle atrophy is common in patients with rheumatoid arthritis (RA). Although neuromuscular electrical stimulation (NMES) is a viable treatment for muscle atrophy, there is no evidence about the use of NMES in patients with RA. The purposes of this multiple-patient case report are: (1) to describe the use of NMES applied to the quadriceps femoris muscles in conjunction with an exercise program in patients with RA; (2) to report on patient tolerance and changes in lean muscle mass, quadriceps femoris muscle strength (force-producing capacity), and physical function; and (3) to explore how changes in muscle mass relate to changes in quadriceps femoris muscle strength, measures of physical function, and patient adherence., Case Description: Seven patients with RA (median age=61 years, range=39-80 years) underwent 16 weeks of NMES and volitional exercises. Lean muscle mass and strength of the quadriceps femoris muscle and physical function were measured before and after treatment., Outcomes: One patient did not tolerate the NMES treatment, and 2 patients did not complete at least half of the proposed treatment. Patients who completed the NMES and volitional exercise program increased their lean muscle mass, muscle strength, and physical function., Discussion: Because of the small sample, whether NMES combined with exercises is better than exercise alone or NMES alone could not be determined. However, the outcomes from this multiple-patient case report indicate that NMES is a viable treatment option to address muscle atrophy and weakness in patients with RA. Strategies to increase tolerance and adherence to NMES are warranted.

Study Design: Test-retest reliability study., Objective: To determine interrater reliability of the modified scapular assistance test (SAT). The modified SAT is designed to assess the contribution of scapular motion to shoulder pain., Background: Abnormal scapular motion has been implicated in different shoulder disorders. However, there is a lack of clinical evaluation tools to assess the scapular component of shoulder dysfunction., Methods and Measures: Forty-six subjects who were referred to physical therapy for treatment of various shoulder pathologies were recruited for this study. The modified SAT was performed on each participant by 2 different examiners. Percent agreement and kappa coefficient were utilized to determine interrater reliability of the modified SAT., Results: The kappa coefficient and percent agreement were .53 and 77%, respectively, when the test was performed in the scapular plane, and .62 and 91%, respectively, when the test was performed in the sagittal plane., Conclusions: The modified SAT possesses acceptable interrater reliability for clinical use.

While exercise has been shown to be beneficial for reducing pain and improving physical function in individuals with knee osteoarthritis (OA), there are still individuals who do not always respond well to this treatment approach. There are a number of factors that have been shown to influence either the degree of disability and/or the progression of disease in individuals with knee OA. These factors include quadriceps inhibition or activation failure, obesity, passive knee laxity, knee alignment, fear of physical activity and self efficacy. It may be possible that varying levels of these factors might also interfere with an individual's ability to participate in an exercise or physical activity program or minimize the benefits that can be achieved by such programs. This paper examines the influence of these factors on physical function and their potential for altering the outcome of exercise therapy programs for individuals with knee OA. Implications and suggestions for potential adjunctive interventions to address these factors in future research and clinical practice are also discussed.

Background and Purpose: There have been conflicting views and evidence reported in the literature concerning differences in muscle torque-generating capacities between clinical ("plug-in") console devices whose power source is provided by an electrical outlet (60 Hz, alternating current-driven) and portable electrical muscle stimulators (smaller, battery-operated stimulators). The purpose of this study was to compare the torque-generating capacity of the quadriceps femoris muscle during neuromuscular electrical stimulation (NMES) between a clinical neuromuscular electrical stimulator (VersaStim 380) and a portable neuromuscular electrical stimulator (Empi 300PV)., Subjects: Forty volunteer subjects with no known knee, neurological, or cardiovascular pathology (22 male, 18 female) participated in the study., Methods: All subjects were tested with the clinical and portable stimulators on 2 separate days. Peak isometric torque of the quadriceps femoris muscle was measured using a Biodex dynamometer. Peak isometric quadriceps femoris muscle torque achieved during NMES and the average quadriceps femoris muscle torque integral produced over 10 NMES contractions were measured for each stimulator. Subjects also rated the amount of pain they experienced during the 10 NMES contractions using a numeric pain scale. Paired t tests were used to compare mean differences in measured variables between stimulator conditions., Results: There were no differences in the peak torque or numeric pain ratings during the electrically stimulated contractions between stimulator conditions. The Empi 300PV produced a greater average torque integral compared with the VersaStim 380 during 10 electrically stimulated contractions (Empi 300PV=988.6-/+330.4 N.m-s, Versastim 380=822.7-/+292.6 N.m-s)., Discussion and Conclusion: The portable Empi 300PV stimulator produced comparable levels of average peak torque at comparable levels of discomfort to those produced by the VersaStim 380 clinical stimulator. The Empi 300PV maintained greater amounts of torque production during a 10-contraction training session compared with the VersaStim 380. Based on these data, we believe that the Empi 300PV has the potential to produce adequate levels of torque production for NMES quadriceps femoris muscle performance training. Further study is needed to determine the effectiveness of using the Empi 300PV for quadriceps femoris muscle performance training.

Purpose of Review: The purposes of this review are to: (1) describe treatments that physical therapists may use to supplement exercise programs to enhance the benefit of rehabilitation, (2) discuss current research related to the mode of delivery of physical therapy treatment, and (3) identify characteristics from recent research that may influence the responsiveness of individuals with knee osteoarthritis to physical therapy., Recent Findings: Physical therapists provide a variety of interventions, such as manual therapy techniques, balance, coordination, and functional retraining techniques, knee taping techniques, electrical stimulation, and foot orthotics to assist in overcoming some of the barriers that make participation in exercise and physical activity difficult. Recent research implies that a number of factors may influence the responsiveness to physical therapy treatment for individuals with knee osteoarthritis. Factors such as the mode of treatment delivery, treatment compliance issues, mechanical characteristics such as joint laxity and malalignment, and radiographic severity are discussed., Summary: Future studies are needed to improve our understanding of factors that can influence the responsiveness of patients with knee osteoarthritis to exercise and physical activity programs. The question may not be which mode of therapy works best, but rather, which patient and/or disease characteristics will tell us who will and who will not respond to a given mode of therapy.

Objective: To determine the reliability, minimum detectable change (MDC), and validity of the Get Up and Go (GUG) test., Design: Repeated-measures test-retest for reliability. Correlational study for validity., Setting: Institutional practice., Participants: Convenience sample of 130 people, 105 with knee osteoarthritis (OA) (80 women; mean age, 62+/-9 y) and 25 healthy controls (21 women; mean age, 57+/-8 y)., Interventions: Not applicable. Main outcome measures Western Ontario and McMaster Universities Osteoarthritis Index, the Activity of Daily Living Scale of the Knee Outcome Survey, and the 8 scales of the Medical Outcomes Study 36-Item Short-Form Health Survey., Results: Intratester and intertester reliability was.95 (95% confidence interval [CI],.72-.98) and.98 (95% CI,.94-.99), respectively. The MDC, based on measurements by a single tester and between testers, was 1.5 and 1.2 seconds, respectively. Time to perform the GUG test was longer for persons with knee OA than it was for the controls (mean difference, 3.3s; 95% CI, 1.8-4.9). Correlations between the GUG test and measures of physical function did not differ significantly from correlations between the GUG test and measures that do not specifically evaluate physical function., Conclusions: The GUG test is reliable and has an MDC that is adequate for clinical use. Validity of the GUG test as a single measure of physical function was not supported. Further research should include testing a battery of performance-based measures of physical function.

Objective: The purpose of this study was to investigate lower extremity movement and muscle activation patterns in individuals with knee osteoarthritis and healthy age- and gender-matched control subjects., Design: This study utilized a non-randomized case-control design to compare 24 subjects with unilateral symptomatic knee osteoarthritis to 24 age- and gender-matched control subjects without knee osteoarthritis., Background: It is hypothesized that knee osteoarthritis is associated with altered lower extremity movement and muscle activation patterns., Methods: A gait analysis was performed to determine the lower extremity movement and muscle activation patterns when walking on a level surface at 1.12 to 1.34 m/s and while descending a 20 cm step. Paired t-tests were used to compare the average of five trials between the groups., Results: Subjects with knee osteoarthritis demonstrated less excursion of the knee in the sagittal plane from heelstrike to peak flexion before midstance (i.e. during loading). Subjects with knee osteoarthritis also demonstrated reduced peak vertical ground reaction forces relative to body weight. The muscle activity patterns were also different between the groups. The vastus lateralis, medial hamstrings, tibialis anterior and medial gastrocnemius were on approximately 1.5 times longer than the same muscles in the control subjects. Additionally, significant increases in muscle co-activation were also observed in individuals with knee osteoarthritis during walking. Similar findings were observed when the subject descended a 20 cm step.

Study Design: Randomized clinical trial, single-masked., Objectives: To determine the effectiveness of using a modified neuromuscular electrical stimulation (NMES) training program as an adjunct treatment for improving quadriceps strength and physical function in rehabilitation following anterior cruciate ligament reconstruction (ACLR)., Background: NMES training for quadriceps strengthening has previously been shown to be an effective adjunct treatment following ACLR when performed against isometric resistance using a dynamometer with the knee positioned in flexion. We developed a modified version of published NMES protocol because some patients have difficulty tolerating the existing protocol and many clinics may not have instrumented dynamometers. There is a need to determine the effectiveness of this modified protocol., Methods and Measures: Forty-three subjects who had undergone ACLR were randomly assigned to either a group that received (NMES group) or did not receive (comparison group) the NMES treatment in conjunction with their rehabilitation. Group means for quadriceps strength and self-reported measures of knee function were compared after 12 and 16 weeks of rehabilitation. The proportion of subjects in each group achieving clinical criteria to initiate ambulation without crutches, treadmill running, and agility training at selected times during rehabilitation were also compared., Results: The NMES group demonstrated moderately greater quadriceps strength at 12 weeks (effect size, 0.48), and moderately higher levels of self-reported knee function at both 12 (effect size, 0.72) and 16 (effect size, 0.65) weeks of rehabilitation compared to the comparison group. A greater proportion of subjects in the NMES group achieved clinical criteria for advancing to agility training at 16 weeks., Conclusions: The modified NMES quadriceps training protocol can be a useful adjunct to ACLR rehabilitation programs, but the treatment effect is smaller than what has been reported in previous studies.

Background and Purpose: People with knee osteoarthritis (OA) sometimes report episodes of knee instability that limit their activities of daily living. The episodes of instability are similar to those reported by people with knee ligament injuries. The authors believe that modifications of interventions that are used to promote knee stability in individuals with knee ligament injuries can be used to enhance knee stability and function in people with knee OA. The purpose of this case report is to describe the development and implementation of an agility and perturbation training program that was used in conjunction with traditional rehabilitation activities for a patient with knee OA., Case Description: The patient was a 73-year-old woman with a diagnosis of bilateral knee OA. Her chief complaints were knee pain and episodes of partial "giving way" at the knee during walking, stair climbing, and participation in tennis and golf. The patient participated in 12 treatment sessions at a frequency of 2 visits per week. The rehabilitation program consisted of lower-extremity stretching, strengthening and endurance exercises that were supplemented with a variety of walking-based agility training techniques, and perturbation training techniques., Outcome: At the completion of rehabilitation, the patient was able to walk on level surfaces and stairs and return to playing golf and tennis without episodes of instability and with reduced pain., Discussion: Supplementing rehabilitation programs for people with knee OA with a modified agility and perturbation training program may assist them in returning to higher levels of physical activity with less pain and instability following rehabilitation. Further research is needed to determine the role of agility and perturbation training in people with knee OA.

Single leg hop tests are commonly used as physical performance measures of function and are also commonly used to evaluate progress in knee rehabilitation programs, particularly for individuals recovering from anterior cruciate ligament injury or reconstructive surgery. While there is some evidence that hop tests may show promise as a predictive measure for identifying individuals who are at risk for recurrent dynamic instability, further work is needed to clearly define the role of hop test measurements for this purpose. The purposes of this clinical commentary are to review the research that has been done to establish hop tests as a physical performance measure of function, to discuss neuromuscular and biomechanical considerations related to hop performance and dynamic knee stability, to discuss existing evidence that supports the potential for hop tests as a predictor of dynamic knee stability, and to discuss considerations for future studies that are designed to more clearly define the role of hop tests in predicting dynamic knee stability.

Objective: To describe movement patterns in people with complete anterior cruciate ligament rupture objectively identified as good candidates for non-operative management of the injury., Design: Involved side kinematics and kinetics were compared to the uninvolved side and to uninjured subjects., Background: High-level athletes with anterior cruciate ligament rupture and poor dynamic stability (non-copers) have movement alterations, including less knee flexion and a decreased internal knee extensor moment during loading response, that are not seen in those with excellent knee stability (copers). Our screening exam can identify people with good rehabilitation potential for non-operative management of anterior cruciate ligament injury (potential copers), but the movement strategies of these individuals are unknown., Methods: Sagittal plane kinematics and kinetics during the stance phase of walking and jogging were collected from 11 subjects who had an acute anterior cruciate ligament rupture and met the criteria of the screening exam, and were compared to 10 uninjured subjects, who we studied previously. Variables were those in which non-copers differed from uninjured subjects., Results: The potential copers flexed their involved knee less than uninjured subjects and their uninvolved side during walking. Potential copers, compared to uninjured subjects, also had a lower vertical ground reaction force during loading response, a lower knee support moment, and an increased ankle support moment during walking. In jogging, the involved knee angle at initial contact was more extended compared to uninjured subjects, and the amount of knee flexion was less than the uninvolved side. No differences in kinetics were present during jogging., Conclusions: This study provides evidence that the potential copers identified by the screening examination have movement patterns that are consistent with people who have more knee stability than non-copers., Relevance: Although potential copers have developed some characteristics of a successful stabilization strategy, the presence of kinematic alterations indicates that they may benefit from training programs designed to enhance dynamic knee stability.

There is growing demand to increase the volume of clinic-based research in physical therapy. Special considerations, unique to the planning and conduct of clinic-based research, need to be addressed to increase the likelihood that these studies will be completed successfully. The purposes of this perspective are to discuss factors affecting clinic-based research and to offer suggestions for addressing these problems when designing and conducting research studies in a clinical setting. This perspective discusses issues such as patient management, determining the availability of target patient populations, acquiring support from physical therapists and physicians, reporting and managing research-related injury or illness, and modifying or terminating projects. Some of the points made in this perspective are illustrated using examples from the authors' experiences in conducting clinical research.

Rehabilitation for a patient with a multiple-ligament knee injury should be designed to reduce pain and swelling, restore range of motion, strength, and endurance, and to enhance proprioception, and dynamic stability of the knee, with the goals of restoring function and minimizing disability. The biomechanics of the knee must be considered when designing a rehabilitation program. General guidelines for rehabilitation of the multiple-ligament-injured knee include considerations for promoting tissue healing, decreasing pain and swelling, restoring full motion, increasing muscular strength and endurance, improving proprioception, enhancing dynamic stability of the knee, and reducing functional limitations and disability. A patient's progression through this sequence must be individualized and depends on the pattern of ligament injury or surgical procedure that was performed, and the principles of tissue healing. Specific guidelines for rehabilitation following ACL reconstruction combined with MCL repair, PCL reconstruction, combined ACL-PCL reconstruction, and reconstruction of the LCL and posterolateral corner have been provided.

Nonoperative management of anterior cruciate ligament (ACL) rupture has not been a successful option for those who participate in high-level physical activity. However, there are instances when patients may want to attempt to return to physically demanding activities with nonoperative rehabilitation for an ACL injury. The purpose of this commentary is to describe guidelines for nonoperative management of physically active individuals with ACL injuries who wish to return to preinjury levels of physical activity. The guidelines are based on the results of 2 clinical studies that improved the overall success of nonoperative management of physically active individuals with ACL ruptures. A decision-making process for selecting appropriate candidates for nonoperative management (rehabilitation candidates) is described. Individuals are classified as rehabilitation candidates if they have no concomitant ligament or mensical damage associated with the ACL injury, have a unilateral ACL injury, and meet all 4 of the following criteria: (1) timed hop test score of 80% or more of the uninjured limb, (2) Knee Outcome Survey Activities of Daily Living Scale score of 80% or more, (3) global rating of knee function of 60% or more, and (4) no more than 1 episode of giving way since the incident injury to the time of testing. Individuals meeting the criteria of a rehabilitation candidate undergo an intensive rehabilitation program before returning to high-level activity. The rehabilitation program consisting of lower extremity muscle strength training, cardiovascular endurance training, agility and sport-specific skill training, and a training program using balance perturbations is described.

This report describes the development and current use of decision-making criteria for returning patients to high-level physical activity with nonoperative management of anterior cruciate ligament ruptures, and presents the results of treatment for patients who met our criteria as candidates for nonoperative rehabilitation and attempted to return to high-level physical activity with nonoperative management. The screening examination consists of four one-legged hop tests, the incidence of knee giving-way, a self-report functional survey, and a self-report global knee function rating. We screened 93 consecutive patients with acute unilateral anterior cruciate ligament rupture, classifying them as either candidates (n = 39, 42%) or noncandidates (n = 54, 58%) for nonoperative management. Of the 39 rehabilitation candidates 28 chose nonoperative management and returned to preinjury activity levels, 22 of whom (79%) returned to preinjury activity levels without further episodes of instability or a reduction in functional status. No patient sustained additional articular or meniscal damage as a result of rehabilitation or return to activity. The decision-making scheme described in this study shows promise in determining who can safely postpone surgical reconstruction and temporarily return to physically demanding activities. Continued study to refine and further validate the decision-making scheme is recommended.

Background and Purpose: The purpose of this study was to determine the effect of change in video display terminal (VDT) height from desktop height (96.5 cm [38 in]) to an elevated position (109.2 cm [43 in]) on postural angles of the head and neck and the effect on cervical spine flexion moments., Subjects: Twenty-seven persons (3 male, 24 female) who spent at least 3 hours per day using a computer while seated were the subjects. The subjects had a mean age of 36.7 years (SD=6.0, range=25-47)., Methods: Subjects were photographed over two 10-minute periods while seated using a computer with the VDT at two different heights. Later, a goniometer was used over images to record angles., Results: There was no difference in cervical flexion moment between the two screen positions. Several postural angles of the head and neck showed changes, but the clinical relevance of these changes is questionable., Conclusion and Discussion: Changing the VDT height from 96.5 to 109.2 cm (floor to midscreen) has no effect on flexion moment on the cervical spine during short periods of VDT operation. If flexion moment is considered a biomechanical indicator of postural stress, it does not appear that the elevated screen position reduces postural stress on the cervical spine during short periods of VDT operation.

Twenty patients with anterior cruciate ligament-deficient knees were studied. Ten patients returned to all sports activities (compensators) and 10 patients were not improved with nonoperative management and required surgical stabilization (noncompensators). Joint laxity was measured using a KT-2000 arthrometer (manual maximum Lachman). Subjects completed a Lysholm questionnaire and Knee Outcome Score. The International Knee Documentation Committee form was also completed. Patients also rated their knee function on a scale of 1 to 100. There was no difference in level and frequency of athletic activity between the two groups before their anterior cruciate ligament injuries as determined by the knee outcome score. The compensator group had a mean side-to-side difference of 3.25 mm at 89 N and the noncompensators had a mean difference of 3 mm preoperatively. Manual maximum tests gave side-to-side differences of 6.7 mm for the compensators and 6 mm for the noncompensators. There were no differences in laxity measures between groups. The correlation between knee outcome scores and side-to-side laxity measurements were not significant. Measurements of anterior laxity in anterior cruciate ligament-deficient patients were not correlated with measures of functional outcome used in this study. Functional outcome measurements that are partially based on joint laxity measures, such as the International Knee Documentation Committee form, may artificially overestimate the disability after anterior cruciate ligament rupture.