Booster visits in the management of the acute musculoskeletal injuries: Transforming care to improve outcomes-A perspective review.

The current healthcare delivery system for patients with acute musculoskeletal injury is failing. Current rehabilitation management of acute musculoskeletal injury typically includes physical therapy, focused on management of impairments, with an eventual transition to functional activities and release to prior level of function. At that point, formal physical therapy is often discontinued, despite the knowledge that a high percentage of patients fail to maintain preinjury level of activity and often reduce participation in regular physical activity. Further, for those who attempt to return to prior levels of pivoting and cutting activities, there is a high second injury rate. The long-term human experience is compromised by the current model of care which terminates at the point of transition to activity. This model of care fails to meet the continued needs of these patients and may result in long term deficits and potential disability. Extended care models include intermittent follow up visits after discharge from an acute episode of care and have been efficacious and cost effective in some patient populations with musculoskeletal conditions. Specifically, a type of extended care model, labeled "booster sessions," represents an opportunity to provide structured, intermittent care to assist in a smooth transition back to function, following an acute episode of care and promote a healthier life outcome. This perspective review will discuss the opportunity to transform acute musculoskeletal care to booster visit care model in an attempt to develop a more efficacious and cost-effective system of care which could be generalizable to all musculoskeletal conditions.

Comparison Between Movement Pattern Training and Strengthening on Kinematics and Kinetics in Patients With Chronic Hip-Related Groin Pain.

The purpose of this study was to compare the preliminary effects of movement pattern training (MoveTrain) versus strengthening/flexibility (standard) treatment on hip and pelvic biomechanics in patients with chronic hip-related groin pain. This is a secondary analysis of data collected during a pilot randomized clinical trial. Thirty patients with hip pain, between the ages of 15 and 40 years, were randomized to MoveTrain or standard. Both groups completed 10 treatment sessions over 12 weeks along with a daily home exercise program. Three-dimensional motion analysis was used to collect kinematic and kinetic data of the pelvis and hip during a single-leg squat task at pretreatment and immediately posttreatment. Compared with the standard group, the MoveTrain group demonstrated smaller hip adduction angles (P = .006) and smaller hip external adduction moments (P = .008) at posttreatment. The desired changes to hip joint biomechanics, as found in this study, may require specificity in training that could allow health care professionals to better customize the rehabilitation of patients with hip pain. These findings can also be applied to the design and implementation of future clinical trials to strengthen our understanding of the long-term implications of different rehabilitation techniques for patients with hip pain.

First Provider Seen for an Acute Episode of Low Back Pain Influences Subsequent Health Care Utilization.

OBJECTIVE: Costs associated with low back pain (LBP) continue to rise. Despite numerous clinical practice guidelines, the evaluation and treatments for LBP are variable and largely depend on the individual provider. As yet, little attention has been given to the first choice of provider. Early research indicates that the choice of first provider and the timing of interventions for LBP appear to influence utilization. We sought to examine the association between the first provider seen and health care utilization. METHODS: Using 2015-2018 data from a large insurer, this retrospective analysis focused on patients (29,806) seeking care for a new episode of LBP. The study identified the first provider chosen and examined the following year of medical utilization. Cox proportional hazards models were calculated using inverse probability weighting on propensity scores to evaluate the time to event and the relationship to the first choice of provider. RESULTS: The primary outcome was the timing and use of health care resources. Total health care use was lowest in those who first sought care with chiropractic care or physical therapy. Highest health care use was seen in those patients who chose the emergency department. CONCLUSION: Overall, there appears to be an association between the first choice of provider and future health care use. Chiropractic care and physical therapy provide nonpharmacologic and nonsurgical, guideline-based interventions. The use of physical therapists and chiropractors as entry points into the health system appears related to a decrease in immediate and long-term use of health resources. This study expands the existing body of literature and provides a compelling case for the influence of the first provider on an acute episode of LBP. IMPACT: The first provider seen for an acute episode of LBP influences immediate treatment decisions, the trajectory of a specific patient episode, and future health care choices in the management of LBP.

Race Differences in Postacute Physical Therapy Utilization and Patient-Reported Function After Total Knee Arthroplasty.

OBJECTIVE: This observational cohort study included patients of Black and White race and non-Hispanic ethnicity with end-stage knee osteoarthritis who were scheduled to receive total knee arthroplasty (TKA) surgery. Our objective was to examine whether race differences exist in the use of physical therapy (PT) across all postacute settings and to examine patient-reported physical function following TKA. METHODS: We collected pre- and postoperative physical function data and postoperative rehabilitation data on 104 Black and White individuals undergoing TKA. Regression analyses and independent samples t-tests were used to explore the predictive value of race on postoperative functional outcome and to compare PT utilization within each postacute setting and across all postacute rehabilitation settings. RESULTS: Total PT received was similar between White and Black participants, but significant race differences in PT utilization existed within specific settings. Race did not significantly predict function after TKA, but Black participants had slightly lower self-reported function both before and after surgery than White participants. CONCLUSION: This is the first study to examine both PT utilization and functional outcomes in a sample of individuals undergoing TKA, and results indicate differences in where postoperative PT is received between Black and White patients.

Comparison between movement pattern training and strengthening on muscle volume, muscle fat, and strength in patients with hip-related groin pain: An exploratory analysis.

The purpose of this exploratory analysis was to compare the impact of movement pattern training (MoveTrain) and standard strength and flexibility training (Standard) on muscle volume, strength and fatty infiltration in patients with hip-related groin pain (HRGP). We completed a secondary analysis of data collected during an assessor-blinded randomized control trial. Data were used from 27 patients with HRGP, 15-40 years, who were randomized into MoveTrain or Standard groups. Both groups participated in their training protocol (MoveTrain, n = 14 or Standard, n = 13) which included 10 supervised sessions over 12 weeks and a daily home exercise program. Outcome measures were collected at baseline and immediately after treatment. Magnetic resonance images data were used to determine muscle fat index (MFI) and muscle volume. A hand-held dynamometer was used to assess isometric hip abductor and extensor strength. The Standard group demonstrated a significant posttreatment increase in gluteus medius muscle volume compared to the MoveTrain group. Both groups demonstrated an increase in hip abductor strength and reduction in gluteus minimus and gluteus maximus MFI. The magnitude of change for all outcomes were modest. Statement of Clinical Significance: Movement pattern training or a program of strength/flexibility training may be effective at improving hipabductor strength and reducing fatty infiltration in the gluteal musculature among those with HRGP. Further research is needed to betterunderstand etiology of strength changes and impact of muscle volume and MFI in HRGP and the effect of exercise on muscle structure andfunction.

Exploring Race Differences in Satisfaction With Rehabilitation Following Total Knee Arthroplasty: A Qualitative Study.

BACKGROUND: The purpose of this qualitative focus group study was to explore race differences in the rehabilitation experience and satisfaction with rehabilitation following total knee arthroplasty (TKA). METHOD: We conducted a series of qualitative focus group discussions with groups of non-Hispanic White and non-Hispanic Black older adults who recently underwent TKA. We used grounded theory approach, which asks the researcher to develop theory from the data that are collected. Participants discussed barriers and facilitators to accessing rehabilitation after surgery, opinions regarding their physical therapists, the amount of postoperative physical therapy received, and overall satisfaction with the postoperative rehabilitation process. RESULTS: Thirty-six individuals participated in focus groups. Three major themes emerged: (i) Participants reported overall positive views of their post-TKA rehabilitation experience. They particularly enjoyed one-on-one care, the ability to participate in "prehabilitation," and often mentioned specific interventions they felt were most helpful in their recovery. (ii) Despite this, substantial barriers to accessing physical therapy exist. These include suboptimal pain management, copayments and other out-of-pocket costs, and transportation to visits. (iii) There were minor differences in the rehabilitation experiences between Black and White participants. Black participants reported longer paths toward surgery and occasional difficulty interacting with rehabilitation providers. CONCLUSIONS: Individuals undergoing TKA can largely expect positive rehabilitation experiences postoperatively. However, some barriers to postoperative physical therapy exist and may differ between Black and White patients. Physical therapists should increase their awareness of these barriers and work to minimize them whenever possible.

One-year outcomes following physical therapist-led intervention for chronic hip-related groin pain: Ancillary analysis of a pilot multicenter randomized clinical trial.

Evidence related to physical therapist-led intervention for patients with chronic hip-related groin pain (HRGP) is limited. The purpose was to assess sustainability of treatment effects for people with HRGP undergoing two physical therapist-led interventions. We completed an ancillary analysis of a pilot multicenter, randomized clinical trial. Forty-six patients with chronic HRGP, 15-40 years, were enrolled. Patients were randomized to participate in 10 sessions over 12 weeks of either movement pattern training (MoveTrain) or traditional strength/flexibility (Standard). Participants completed self-report questionnaires before treatment and 6 and 12 months after treatment completion. Outcome measures included Hip disability and Osteoarthritis and Outcome Score (HOOS), Patient Specific Functional Scale and Numeric Pain Rating Scale for average and worst pain. Continuous data were analyzed with mixed model repeated measures analysis of variance (RM-ANOVA) within each group. Numeric pain rating scale (NPRS) was analyzed using multinomial generalized estimating equations (GEE) with a cumulative logit. Reported p values are from statistical contrasts within the RM-ANOVAs and GEEs testing a priori hypotheses regarding change from pretest to month 6, and pretest to month 12. A total of 43/46 (93.5%) participants completed treatment, 40 (87.0%) completed 6 and 38 (82.6%) completed 12 month questionnaires. At 6 and 12 months, both groups demonstrated clinically significant improvements, compared to pretest, in all subscales of HOOS (p < 0.01), Patient Specific Functional Scale (p < 0.001), and NPRS (p < 0.0001). Among patients with chronic HRGP, both MoveTrain and Standard resulted in improved outcomes that were sustained 12 months after treatment. Further investigation in a larger sample is needed to confirm our findings.

Promoting Physical Activity in Older Adults With Knee Osteoarthritis and Hypertension: A Randomized Controlled Trial.

A 6-month self-efficacy intervention was compared with attention-control intervention on physical activity, clinical outcomes, and mediators immediate postintervention and 6-month postintervention in 182 older adults with knee osteoarthritis and hypertension using a randomized controlled trial design. The intervention group received six weekly individual physical therapy sessions for lower-extremity exercise and fitness walking and nine biweekly nurse telephone counseling sessions. The attention-control group received six weekly and nine biweekly nurse telephone sessions on health topics. Lower-extremity exercise was assessed by e-diary; fitness walking was assessed by accelerometer and e-diary; blood pressure was assessed by automated monitor; function was assessed by performance-based tests and questionnaires; and pain, self-efficacy, and outcome expectancy were assessed by questionnaires. Self-reported lower-extremity exercise and fitness walking, function, pain, self-efficacy, and outcome expectancy showed significant group or group by time effects favoring intervention. The intervention did not improve physical activity by accelerometer and blood pressure. Mean minutes of fitness walking fell short of the 150 min/week goal.

Combining advanced computational and imaging techniques as a quantitative tool to estimate patellofemoral joint stress during downhill gait: A feasibility study.

BACKGROUND: The onset and progression of patellofemoral osteoarthritis (OA) has been linked to alterations in cartilage stress-a potential precursor to pain and subsequent cartilage degradation. A lack in quantitative tools for objectively evaluating patellofemoral joint contact stress limits our understanding of pathomechanics associated with OA. RESEARCH QUESTION: Could computational modeling and biplane fluoroscopy techniques be used to discriminate in-vivo, subject-specific patellofemoral stress profiles in individuals with and without patellofemoral OA? METHODS: The current study employed a discrete element modeling framework driven by in-vivo, subject-specific kinematics during downhill gait to discriminate unique patellofemoral stress profiles in individuals with patellofemoral OA (n = 5) as compared to older individuals without OA (n = 6). All participants underwent biplane fluoroscopy kinematic tracking while walking on a declined instrumented treadmill. Subject-specific kinematics were combined with high resolution geometrical models to estimate patellofemoral joint contact stress during 0%, 25 %, 50 %, 75 % and 100 % of the loading response phase of downhill gait. RESULTS: Individuals with patellofemoral OA demonstrated earlier increases in patellofemoral stress in the lateral patellofemoral compartment during loading response as compared to OA-free controls (P = 0.021). Overall, both groups exhibited increased patellofemoral contact stress early in the loading response phase of gait as compared to the end of loading response. Results from this study show increased stress profiles in individuals with patellofemoral OA, indicating increasing joint loading in early phases of gait. SIGNIFICANCE: This modeling framework-combining arthrokinematics with discrete element models-can objectively estimate changes in patellofemoral joint stress, with potential applications to evaluate outcomes from various treatment programs, including surgical and non-surgical rehabilitation treatments.

Implementing stratified care for acute low back pain in primary care using the STarT Back instrument: a process evaluation within the context of a large pragmatic cluster randomized trial.

BACKGROUND: Although risk-stratifying patients with acute lower back pain is a promising approach for improving long-term outcomes, efforts to implement stratified care in the US healthcare system have had limited success. The objectives of this process evaluation were to 1) examine variation in two essential processes, risk stratification of patients with low back pain and referral of high-risk patients to psychologically informed physical therapy and 2) identify barriers and facilitators related to the risk stratification and referral processes. METHODS: We used a sequential mixed methods study design to evaluate implementation of stratified care at 33 primary care clinics (17 intervention, 16 control) participating in a larger pragmatic trial. We used electronic health record data to calculate: 1) clinic-level risk stratification rates (proportion of patients with back pain seen in the clinic over the study period who completed risk stratification questionnaires), 2) rates of risk stratification across different points in the clinical workflow (front desk, rooming, and time with clinician), and 3) rates of referral of high-risk patients to psychologically informed physical therapy among intervention clinics. We purposively sampled 13 clinics for onsite observations, which occurred in month 24 of the 26-month study. RESULTS: The overall risk stratification rate across the 33 clinics was 37.8% (range: 14.7-64.7%). Rates were highest when patients were identified as having back pain by front desk staff (overall: 91.9%, range: 80.6-100%). Rates decreased as the patient moved further into the visit (rooming, 29.3% [range: 0-83.3%]; and time with clinician, 11.3% [range: 0-49.3%]. The overall rate of referrals of high-risk patients to psychologically informed physical therapy across the 17 intervention clinics was 42.1% (range: 8.3-70.8%). Barriers included staffs' knowledge and beliefs about the intervention, patients' needs, technology issues, lack of physician engagement, and lack of time. Adaptability of the processes was a facilitator. CONCLUSIONS: Adherence to key stratified care processes varied across primary care clinics and across points in the workflow. The observed variation suggests room for improvement. Future research is needed to build on this work and more rigorously test strategies for implementing stratified care for patients with low back pain in the US healthcare system. TRIAL REGISTRATION: Trial registration: ClinicalTrials.gov ( NCT02647658 ). Registered January 6, 2016.

Movement pattern training compared with standard strengthening and flexibility among patients with hip-related groin pain: results of a pilot multicentre randomised clinical trial.

STUDY DESIGN: Pilot, multicentre randomised clinical trial (RCT). OBJECTIVES: Assess viability of performing a definitive RCT and compare preliminary effects of movement pattern training (MoveTrain) and strengthening/flexibility (Standard) to improve function in people with chronic hip-related groin pain (HRGP). BACKGROUND: To determine the best physical therapist-led intervention for patients with HRGP, we must understand treatment effects of different treatment modes. METHODS: Forty-six patients (17M:29F; 29±5.3 years; body mass index 25.6±6.3 kg/m2) with HRGP were randomised. MoveTrain included task-specific training to optimise biomechanics during daily tasks. Standard included strengthening/flexibility. Treatment included 10 visits/12 weeks and home exercise programme (HEP). Primary outcomes for feasibility were recruitment, retention, treatment adherence and treatment fidelity. Secondary outcomes were patient-reported function (Hip disability and Osteoarthritis Outcome Score (HOOS)), lower extremity kinematics and hip muscle strength. RESULTS: We achieved target recruitment, and retention was excellent (91%). Patient session attendance was high (93%); however, reported HEP adherence (62%) was lower than expected. Physical therapists' adherence to treatment protocols was high (90%). Patients demonstrated high treatment receipt; 91% of exercises performed were rated independent. Both groups demonstrated clinically important improvements in function (HOOS) and muscle strength; however, there were no between-group differences (HOOS subscales, p≥0.13, strength, p≥0.34). Compared with Standard, MoveTrain demonstrated greater reductions in hip adduction (p=0.016) and pelvic drop (p=0.026) during a single leg squat. No adverse events were noted. CONCLUSION: Our experience in completing this RCT confirmed that a larger, multicentre RCT is feasible and highlighted modifications we will implement to optimise the future RCT. TRIAL REGISTRATION NUMBER: NCT02913222.

Improving Patient Reported Outcomes and Preventing Depression and Anxiety in Older Adults With Knee Osteoarthritis: Results of a Sequenced Multiple Assignment Randomized Trial (SMART) Study.

OBJECTIVE: Older adults with knee osteoarthritis (OA) and comorbid subsyndromal depressive symptoms are at elevated risk for incidental major depression or anxiety disorders. Using an indicated prevention paradigm, the authors conducted a sequenced multiple assignment randomized trial (SMART) to: 1) evaluate the effect of cognitive behavioral therapy (CBT) and physical therapy (PT), together with the temporal ordering of these interventions, on patient-reported global impression of change (P-GIC), mood, anxiety, and pain; and 2) compare the strategies' impact on incidence of common psychiatric disorders over 12-months. METHODS: This intervention development trial compared four adaptive strategies delivered in two stages (each up to 8 weeks), contrasted with enhanced usual care (EUC). The strategies were CBT followed by an increased dose of CBT (CBT-CBT), CBT followed by PT (CBT-PT), PT followed by an increased dose of PT (PT-PT), and PT followed by CBT (PT-CBT). Participants (n = 99) were aged 60 years and older and met clinical criteria for knee OA and subthreshold depression. Response was defined as at least "much better" on the P-GIC. Participants were assessed quarterly for 12 months for incidence of psychiatric disorders. RESULTS: Stage 1 response was higher for PT (47.5%) compared to CBT (20.5%). Non-responders receiving an additional dose of the same intervention experienced a response rate of 73%, higher than for switching to a different intervention. All strategies were superior to EUC (5%). Although not powered to detect effects on disorders, neither intervention strategy nor response status affected 12-month incidence of depression and anxiety disorders. CONCLUSION: As response rates were similar for PT-PT and CBT-CBT, it may be dose and not type of these interventions that are necessary for clinical benefit. For non-responders, this finding may guide providers to stay the clinical course for up to 12 weeks before switching. These results support future trials of SMART designs in late-life depression prevention.

Neuromuscular Electrical Stimulation Compared to Volitional Exercise for Improving Muscle Function in Rheumatoid Arthritis: A Randomized Pilot Study.

OBJECTIVE: The aim of this study was to compare the feasibility and effectiveness of neuromuscular electrical stimulation (NMES) with that of high-intensity volitional resistance training for improving muscle structure and function and physical function in patients with rheumatoid arthritis (RA). We also compared pre-intervention and post-intervention values of myocyte characteristics. METHODS: In this 2-group, single-blind, randomized pilot study, adult patients with RA were assigned to 36 sessions of NMES (n = 31 patients) or volitional training (n = 28 patients) over 16 weeks. Outcome measures included muscle structure and function (quadriceps muscle area, density, and strength), physical function (performance-based and patient-reported), feasibility (increased pain, increased disease activity, attrition, and adherence), and myocyte characteristics (area, proportion of type I or II muscle fibers, and intramyocellular lipid content). Analysis of covariance was used to compare groups. RESULTS: The intervention intensity in the NMES group was less than half that in the volitional exercise group (31% versus 77% of maximum effort). Both groups experienced significant improvements in muscle structure and function (P < 0.001 to 0.019). Improvements in muscle characteristics and physical function were not different between groups. Exercise did not result in serious adverse events or increases in pain and disease activity. Attrition was 29% in the NMES group and 7% in the volitional exercise group. CONCLUSION: Both NMES and high-intensity volitional resistance training can be used as effective approaches to improving muscle structure and function in patients with RA. NMES may be a viable alternative for improving muscle function in patients in whom high-intensity resistance exercise may not be tolerated or is contraindicated, but attrition must be considered when using this approach.

Development and Evaluation of the Boston University Osteoarthritis Functional Pain Short Form (BU-OA-FPS).

Background: Pragmatic studies have gained popularity, thus emphasizing the need for patient-reported outcomes (PRO) to be integrated into electronic health records. Objective: This study describes the development of a customized short form from the Boston University Osteoarthritis Functional Assessment PRO (BU-OA-PRO) for a specific pragmatic clinical trial. Methods: A Functional Pain Short Form was created from an existing item bank of deidentified data in the BU-OA-PRO. Item response theory (IRT) methods were used to select items. Reliability was measured with the Cronbach alpha, then with IRT simulation methods. To examine validity, ceiling and floor effects, correlations between the short-form scores and scores from the BU-OA-PRO and the Western Ontario McMasters University Osteoarthritis Index (WOMAC) Pain and Difficulty subscales, and the area under the curve (AUC) were calculated. A minimum detectable change at 90% confidence (MDC90) was calculated based on a calibration sample. Results: The BU-OA-PRO was reduced from 126 items to 10 items to create the BU-OA Functional Pain Short Form (BU-OA-FPS). The Cronbach alpha indicated high internal consistency (0.91), and reliability distribution estimates were 0.96 (uniform) and 0.92 (normal). Low ceiling effects (4.57%) and floor effects (0%) were found. Moderate-to-high correlations between the BU-OA-PRO and BU-OA-FPS were found with WOMAC Pain (BU-OA-FPS = 0.67; BU-OA-PRO = 0.64) and Difficulty (BU-OA-FPS = 0.73; BU-OA-PRO = 0.69) subscales. The correlation between the BU-OA-PRO and BU-OA-FPS was 0.94. The AUC ranged from 0.80 to 0.88. The MDC90 was approximately 6 standardized points. Conclusions: The BU-OA-FPS provides reliable and valid measurement of functional pain. Pragmatic studies may consider the BU-OA-FPS for use in electronic health records to capture outcomes.

Association of Early Outpatient Rehabilitation With Health Service Utilization in Managing Medicare Beneficiaries With Nontraumatic Knee Pain: Retrospective Cohort Study.

BACKGROUND: Nontraumatic knee pain (NTKP) is highly prevalent in adults 65 years of age and older. Evidence-based guidelines recommend early use of rehabilitation; however, there is limited information comparing differences in health care utilization when rehabilitation is included in the management of NTKP. OBJECTIVES: To describe the overall health care utilization associated with the management of NTKP; estimate the proportion of people who receive outpatient rehabilitation services; and evaluate the timing of outpatient rehabilitation and its association with other health care utilization. DESIGN: Rretrospective cohort study was conducted using a random 10% sample of 2009-2010 Medicare claims. The sample included 52,504 beneficiaries presenting within the ambulatory setting for management of NTKP. METHODS: Exposure to outpatient rehabilitative services following the NTKP index ambulatory visit was defined as 1) no rehabilitation; 2) early rehabilitation (1-15 days); 3) intermediate rehabilitation (16-120 days); and 4) late rehabilitation (>120 days). Logistic regression models were fit to analyze the association of rehabilitation timing with narcotic analgesic use, utilization of nonsurgical invasive procedure, and knee surgery during a 12-month follow-up period. RESULTS: Only 11.1% of beneficiaries were exposed to outpatient rehabilitation services. The likelihood of using narcotics, nonsurgical invasive procedures, or surgery was significantly less (adjusted odds ratios; 0.67, 0.50, 0.58, respectively) for those who received early rehabilitation when compared to no rehabilitation. The exposure-outcome relationships were reversed in the intermediate and late rehabilitation cohorts. LIMITATIONS: This was an observational study, and residual confounding could affect the observed relationships. Therefore, definitive conclusions regarding the causal effect of rehabilitation exposure and reduced utilization of more aggressive interventions cannot be determined at this time. CONCLUSIONS: Early referral for outpatient rehabilitation may reduce the utilization of health services that carry greater risks or costs in those with NTKP.

Task-Specific Training for Adults With Chronic Knee Pain: A Case Series.

Study Design Case series. Background Recent evidence suggests that traditional impairment-based rehabilitation approaches for patients with knee pain may not result in improved function or reduced disability. This case series describes a novel task-specific training approach to exercise therapy for patients with chronic knee pain and reports changes in measures of clinical outcome (pain and physical function) following participation in the training program. Case Description Seven patients with chronic knee pain aged 40 years or older were included. Each reported at least "moderate" difficulty with sit-to-stand transfers, floor transfers, and/or stair negotiation at baseline. Experienced physical therapists provided between 8 and 16 treatment sessions focusing on improving performance of difficult or painful tasks. Outcomes A majority of patients demonstrated clinically important improvements in both patient-rated outcomes (Knee injury and Osteoarthritis Outcome Score, numeric pain-rating scale, modified Arthritis Self-Efficacy Scale) and performance-based outcomes (30-second chair-rise test, timed stair-climb test, floor transfer test, Performance Assessment of Self-Care Skills). Discussion A task-specific training approach for patients with chronic knee pain was described and yielded considerable improvement in pain and function for most of the individuals in this case series. Larger studies are needed to determine how task-specific training compares with more traditional impairment-based exercise approaches for chronic knee pain. Level of Evidence Therapy, level 5. J Orthop Sports Phys Ther 2017;47(8):548-556. doi:10.2519/jospt.2017.7349.

Responsiveness of Physical Activity Measures Following Exercise Programs after Total Knee Arthroplasty.

BACKGROUND: Few instruments that measure physical activity (pa) can accurately quantify pa performed at light and moderate intensities, which is particularly relevant to older adults. Evidence for responsiveness of these instruments after an intervention is limited. OBJECTIVES: o estimate and compare the responsiveness of two activity monitors and one questionnaire in assessing PA after an intervention following total knee Arthroplasty. METHODS: This one-group pretest-posttest, repeated-measures study analyzed changes in duration of daily PA and the standardized response mean (SRM) to assess internal responsiveness that were compared across instruments. Correlations between changes in PA measured by the proposed instruments and the global rating of change were used to test external responsiveness. Agreement between PA instruments on identifying individuals who changed their PA based on measurement error was assessed using weighted-Kappa (K). RESULTS: Thirty subjects, mean age 67(6) and 73% female, were analyzed. Changes in PA measured by each instrument were small (p>0.05), resulting in a small degree of responsiveness (SRM<0.30). Global rating of change scores did not correlate with changes in PA (rho=0.13-0.28, p>0.05). The activity monitors agreed on identifying changes in moderate-intensity PA (K=0.60) and number of steps (K=0.63), but did not agree with scores from questionnaire(K≤0.22). CONCLUSION: Analyzing group-based changes in PA is challenging due to high-variability in the outcome. Investigating changes in PA at the individual-level may be a more viable alternative.

Test-Retest Reliability of Rating of Perceived Exertion and Agreement With 1-Repetition Maximum in Adults.

Study Design Clinical measurement. Background It has been suggested that rating of perceived exertion (RPE) may be a useful alternative to 1-repetition maximum (1RM) to determine proper resistance exercise dosage. However, the test-retest reliability of RPE for resistance exercise has not been determined. Additionally, prior research regarding the relationship between 1RM and RPE is conflicting. Objectives The purpose of this study was to (1) determine test-retest reliability of RPE related to resistance exercise and (2) assess agreement between percentages of 1RM and RPE during quadriceps resistance exercise. Methods A sample of participants with and without knee pathology completed a series of knee extension exercises and rated the perceived difficulty of each exercise on a 0-to-10 RPE scale, then repeated the procedure 1 to 2 weeks later for test-retest reliability. To determine agreement between RPE and 1RM, participants completed knee extension exercises at various percentages of their 1RM (10% to 130% of predicted 1RM) and rated the perceived difficulty of each exercise on a 0-to-10 RPE scale. Percent agreement was calculated between the 1RM and RPE at each resistance interval. Results The intraclass correlation coefficient indicated excellent test-retest reliability of RPE for quadriceps resistance exercises (intraclass correlation coefficient = 0.895; 95% confidence interval: 0.866, 0.918). Overall percent agreement between RPE and 1RM was 60%, but agreement was poor within the ranges that would typically be used for training (50% 1RM for muscle endurance, 70% 1RM and greater for strength). Conclusion Test-retest reliability of perceived exertion during quadriceps resistance exercise was excellent. However, agreement between the RPE and 1RM was poor, especially in common training zones for knee extensor strengthening. J Orthop Sports Phys Ther 2016;46(9):768-774. Epub 5 Aug 2016. doi:10.2519/jospt.2016.6498.

Knee joint contact mechanics during downhill gait and its relationship with varus/valgus motion and muscle strength in patients with knee osteoarthritis.

OBJECTIVE: The objective of this exploratory study was to evaluate tibiofemoral joint contact point excursions and velocities during downhill gait and assess the relationship between tibiofemoral joint contact mechanics with frontal-plane knee joint motion and lower extremity muscle weakness in patients with knee osteoarthritis (OA). METHODS: Dynamic stereo X-ray was used to quantify tibiofemoral joint contact mechanics and frontal-plane motion during the loading response phase of downhill gait in 11 patients with knee OA and 11 control volunteers. Quantitative testing of the quadriceps and the hip abductor muscles was also performed. RESULTS: Patients with knee OA demonstrated larger medial/lateral joint contact point excursions (p < 0.02) and greater heel-strike joint contact point velocities (p < 0.05) for the medial and lateral compartments compared to the control group. The peak medial/lateral joint contact point velocity of the medial compartment was also greater for patients with knee OA compared to their control counterparts (p = 0.02). Additionally, patients with knee OA demonstrated significantly increased frontal-plane varus motion excursions (p < 0.01) and greater quadriceps and hip abductor muscle weakness (p = 0.03). In general, increased joint contact point excursions and velocities in patients with knee OA were linearly associated with greater frontal-plane varus motion excursions (p < 0.04) but not with quadriceps or hip abductor strength. CONCLUSION: Altered contact mechanics in patients with knee OA may be related to compromised frontal-plane joint stability but not with deficits in muscle strength.