Recovery Curve for Patient Reported Outcomes and Objective Physical Activity After Primary Total Knee Arthroplasty-A Multicenter Study Using Wearable Technology.

BACKGROUND: This study aimed to describe the trajectory of recovery based on patient-reported outcomes (PROs) and objective metrics of physical activity measures over the first 12 months post-total knee arthroplasty (TKA). METHODS: In total, 1,005 participants who underwent a primary unilateral TKA surgery between November 2018 and September 2021 from a multisite prospective study were analyzed. Generalized estimating equations were used to evaluate PROs and objective physical activity measures over time. RESULTS: All Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR), EuroQol-5D (EQ-5D), and steps per day scores were greater than preoperative scores (P < .05). The flights of stairs per day, gait speed, and walking asymmetry all declined at 1 month (all, P < .001). However, all subsequent scores improved by 6 months (all, P < .01). The greatest clinically important differences from previous visit in KOOS JR (ß = 18.1; 95% Confidence Interval (CI) = 17.2, 19.0), EQ-5D (ß = 0.11; 95% CI = 0.10, 0.12), steps per day (ß = 1,169.3; 95% CI = 1,012.7, 1,325.9), gait speed (ß = -0.05; 95% CI = -0.06, -0.03), and walking asymmetry (ß = 0.00; 95% CI = -0.03, 0.03) were observed at 3 months. CONCLUSION: The KOOS JR, EQ-5D, and steps per day measures showed earlier improvements than other physical activity metrics, with the greatest magnitude of improvement within the first 3 months post-TKA. The greatest magnitude of improvement in walking asymmetry was not observed until 6 months, while gait speed and flights of stairs per day were not observed until 12 months. This data may further help provide expectation setting information to patients before surgery, and may aid in identifying outliers to the normal recovery curve who may benefit from targeted interventions.

Lower Limb Extension Power is Associated With Slope Walking Joint Loading Mechanics in Older Adults.

Fall-related injuries are associated with muscle weakness and common during slope walking in older adults. However, no study has evaluated the relationship between muscle weakness, measured by maximal lower limb extension power, and older adults' ability to navigate slope walking for a better understanding of fall prevention. Therefore, the purpose of this study was to investigate the association between maximal lower limb extension power and joint mechanics during slope walking. Fifteen healthy older adults were tested. Lower limb extension power was measured using the Leg Extension Power Rig. Kinematic and kinetic analysis was performed during level (0°), incline (10°), and decline (10°) slope walking. Greater maximal lower limb extension power was significantly (p < .050; Cohen's f2 > 0.35) associated with multiple kinetic and kinematic joint mechanic variables across stance phase of the gait cycle during level, incline, and decline walking. These findings will allow clinicians to better educate patients and develop interventions focused on fall prevention and improving functional mobility in older adults.

Reference chart for knee flexion following total knee arthroplasty: a novel tool for monitoring postoperative recovery.

BACKGROUND: Clinicians and patients lack an evidence-based framework by which to judge individual-level recovery following total knee arthroplasty (TKA) surgery, thus impeding personalized treatment approaches for this elective surgery. Our study aimed to develop and validate a reference chart for monitoring recovery of knee flexion following TKA surgery. METHODS: Retrospective analysis of data collected in routine rehabilitation practice for patients following TKA surgery. Reference charts were constructed using Generalized Additive Models for Location Scale and Shape. Various models were compared using the Schwarz Bayesian Criterion, Mean Squared Error in 5-fold cross validation, and centile coverage (i.e. the percent of observed data represented below specified centiles). The performance of the reference chart was then validated against a test set of patients with later surgical dates, by examining the centile coverage and average bias (i.e. difference between observed and predicted values) in the test dataset. RESULTS: A total of 1173 observations from 327 patients were used to develop a reference chart for knee flexion over the first 120 days following TKA. The best fitting model utilized a non-linear time trend, with smoothing splines for median and variance parameters. Additionally, optimization of the number of knots in smoothing splines and power transformation of time improved model fit. The reference chart performed adequately in a test set of 171 patients (377 observations), with accurate centile coverage and minimal average bias (< 3 degrees). CONCLUSION: A reference chart developed with clinically collected data offers a new approach to monitoring knee flexion following TKA.

Characteristics of young and lower functioning patients following total knee arthroplasty: a retrospective study.

BACKGROUND: Rates of total knee arthroplasty (TKA) procedures in younger, more medically complex patients have dramatically increased over the last several decades. No study has examined categorization of lower and higher functioning subgroups within the TKA patient population. Our study aimed to determine preoperative characteristics of younger patients who are lower functioning following TKA. METHODS: Patients were categorized into higher and lower functioning subgroups defined using a median split of 1) postoperative Timed Up and Go (TUG) test times and 2) Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical function subscale scores. A split in age (65 years) was used to further classify patients into four categories: younger lower functioning, younger higher functioning, older lower functioning and older higher functioning. Measures from preoperative domains of health, psychological, physical performance and pain severity were examined for between-group differences. RESULTS: Comparing mean values, the younger lower functioning subgroup using the TUG had significantly weaker knee extensor, slower gait speed, higher body mass index and greater pain compared to other subgroups. The younger lower functioning subgroup using the WOMAC physical function subscale demonstrated higher pain levels and Coping Strategies Questionnaire-Catastrophizing Subscale scores compared to the older lower functioning subgroup. CONCLUSIONS: Poorer preoperative physical performance and pain severity appear to have the largest influence on early postoperative TKA recovery in younger lower functioning patients relative to both younger and older higher functioning patients.

Effect of Physical Therapy Visits on Clinical Outcomes Following Anterior Cruciate Ligament Reconstruction With and Without Concurrent Meniscal Repair.

BACKGROUND: Health care payment reform has increased employers and health insurance companies' incentive to take measures to control the rising costs of medical care in the United States. To date, limited research has investigated the influence outpatient physical therapy (PT) visits have on clinical outcomes following anterior cruciate ligament reconstruction (ACLR) with and without a concurrent meniscal repair. OBJECTIVE: To examine the relationship between the number of PT visits and patient-reported outcome scores following ACLR outpatient rehabilitation. STUDY DESIGN: Retrospective cohort. LEVEL OF EVIDENCE: 2b. METHODS: Patients following ACLR with (n = 62) and without (n = 328) meniscal repair were identified through an electronic medical record database. RESULTS: Patients with more PT visits had higher knee outcome survey-activities of daily living (KOS-ADL) change scores (P = .01) following ACLR without meniscal repair. Younger patients yielded significantly higher KOS-ADL change scores (P = .05) in the same cohort. Patients in the semisupervised PT visit strata recorded an 11.1 higher KOS-ADL change score compared with patients within the unsupervised PT visit stratum (P = .02). Younger patients also yielded significantly larger reductions in numeric pain (P = .01) following ACLR without meniscal repair. No significant differences were found between PT visits and either patient-reported outcome following ACLR with meniscal repair. CONCLUSIONS: Our findings suggest that younger patients and those in a semisupervised PT visit model have superior patient-reported outcomes following ACLR without meniscal repair. Preliminary findings indicate no relationship with PT visits and patient-reported outcomes in patients after ACLR with meniscal repair surgery. CLINICAL RELEVANCE: These findings promote an alternative model to outpatient PT following ACLR without meniscal repair that may be more clinically effective and value based. There appears to be a need for patients to undergo a balanced regimen of supervised PT and effective interventions that can be conducted independently.

The Recovery Curve for the Patient-Reported Outcomes Measurement Information System Patient-Reported Physical Function and Pain Interference Computerized Adaptive Tests After Primary Total Knee Arthroplasty.

BACKGROUND: We sought to characterize the typical recovery in physical function (PF) and pain interference (PI) after TKA using Patient-Reported Outcomes Measurement Information System (PROMIS) patient-reported outcome (PRO) measures. METHODS: Ninety-one patients were enrolled into an institutional review board -approved prospective observational study. PROs were obtained preoperatively and postoperatively at 6 weeks, 3 months, 6 months, and 1 year. PROs included the PROMIS PF computerized adaptive test (CAT) and the PROMIS PI CAT. Generalized estimating equations were used to evaluate outcomes over time. RESULTS: There was no difference in the preoperative and 6-week postoperative T-scores for the PF CAT (P = .410). However, all subsequent postoperative T-scores were greater than the preoperative T-score (all, P < 0.05). There was a significant reduction in PI CAT T-scores between the preoperative and all subsequent postoperative T-scores (all, P < .05). A clinically important difference in PF CAT T-scores (ß = 5.44, 95% confidence interval 4.10-6.80; P < .001) and PI CAT T-scores (ß = -7.46, 95% confidence interval -9.52 to -5.40; P < 0.001) was seen between the preoperative and 3-month postoperative visits. Sixty-three percent of the improvement in PF occurred by 3 months, and 89% had occurred by 6 months. The majority of reduction in PI (68%) occurred by 3 months and 90% had occurred by 6 months. CONCLUSION: The greatest magnitude of improvement in both PF and PI occurred within the first 3 months. After 6 months, patients might expect modest improvements in PF and mild reductions of PI. Patients and surgeons should use this information for setting expectations, planning for recovery, and improving care.

Higher Frequency of Reoperation With a New Bicruciate-retaining Total Knee Arthroplasty.

BACKGROUND: With as many as 25% of patients reporting residual knee symptoms after primary total knee arthroplasty (TKA), alternative implant designs and surgical techniques have been proposed to further reduce these symptoms. There is growing evidence that retention of the anterior cruciate ligament (ACL) results in more natural knee kinematics; thus, implants with more normal joint mechanics could provide improved physical function postoperatively and reduce the amount of residual symptoms. Advancements in the bicruciate-retaining (BCR) TKA implant design have been made, and based on these, we wished to compare the BCR with a more traditional cruciate-retaining (CR) implant. QUESTIONS/PURPOSES: (1) Was there a difference in the risk of reoperation after primary TKA between BCR and CR implant designs? (2) Was there a difference in the radiographic findings of radiolucent lines (RLLs) between the implant designs? (3) Was there a difference in patient-reported and clinical outcomes between the two implant designs? METHODS: Between January 2013 and May 2014, two surgeons performed 475 primary TKAs. During this time, 78 (16%) of these were performed with BCR implants and 294 (62%) with CR implants; the remainder were performed with anterior-stabilized or more constrained designs as a result of increased deformity and/or ligamentous deficiencies. During this period, the general indications for BCR TKA were arthritic knees with only slight to moderate deformity and sufficient ligamentous integrity of both the ACL and posterior cruciate ligament. The indications for CR TKA were similar other than these patients presented with a deficient ACL. A total of 66 (85%) of the BCR and 237 (81%) of the CR TKAs were available for followup at a minimum of 12 months or when reoperation occurred before 12 months (mean, 18 months; range, 2-32 months). With the numbers available, there were no differences between the groups in terms of age and sex, but the patients undergoing CR TKA had a greater mean body mass index (33 ± 7 versus 31 ± 5 kg/m2, p = 0.032). The frequency of early reoperation was compared between the groups as were radiographic evidence of RLL, patient-reported outcomes, and knee range of motion (ROM). RESULTS: Knees in the BCR group had a higher frequency of all-cause revision (5% [three of 66] versus 1.3% [three of 237]; hazard ratio (HR), 7.44; 95% confidence interval [CI], 1.24-44.80; p = 0.028). Knees in the BCR group had a higher frequency of irrigation and débridement with component retention (HR, 0.07; 95% CI, 0.02-0.28; p < 0.001). No differences were found between groups for subsequent manipulation (HR, 0.34; 95% CI, 0.08-1.42; p = 0.137). The proportion of RLLs was greater in the BCR group (HR, 2.93; 95% CI, 1.62-5.32; p < 0.001) compared with the CR group. There were no differences between the groups in terms of the Physical Function Computerized Adaptive Test scores, Global10 scores or knee ROM outcomes. CONCLUSIONS: Preliminary short-term findings suggest the BCR implant has inferior survivorship and concerning radiographic findings when compared with a conventional CR implant with respect to complications after primary TKA. These findings raise concerns about the new BCR design; however, further randomized trials are necessary to determine superiority between alternative implant designs. LEVEL OF EVIDENCE: Level III, therapeutic study.

The effects of early aggressive rehabilitation on outcomes after anterior cruciate ligament reconstruction using autologous hamstring tendon: a randomized clinical trial.

STUDY DESIGN: Prospective randomized clinical trial. METHODS AND MEASURES: Thirty-six patients who had a primary anterior cruciate ligament reconstruction (ACL-R) with a semitendinosus-gracilis (STG) autograft from a single orthopedic surgeon were prospectively randomized into 2 groups. Nineteen patients were randomized to the aggressive group (53% male, mean age 30.1 + 10.5 y) and 17 to the nonaggressive group (88% male, mean age 33.1 + 10.9 y). Impairment measures of anteroposterior (A-P) knee laxity, range of motion (ROM), and peak isometric force (PIF) values were obtained 12 wk postoperatively. Subjective response to the International Knee Documentation Committee knee form (IKDC) was collected 1, 12, and 24 wk postoperatively. One-way ANOVA was used to analyze differences between groups at 12 wk for A-P knee laxity, ROM, and PIF. Differences between the groups for the IKDC scores were determined using 1-way ANOVA with repeated measures 1, 12, and 24 wk postoperatively. Bonferroni adjustment was used for multiple comparisons. RESULTS: There were no differences between the groups for the baseline characteristics (P > .05). There was no difference found between the groups in respect to A-P knee laxity, ROM, or PIF at 12 wk (P > .05). Further analysis also showed no significant differences in the IKDC scores between groups at 12 or 24 wk (P > .05). CONCLUSIONS: No differences were found between early aggressive and nonaggressive rehabilitation after an isolated ACL-R using STG autografts for the primary outcomes of A-P knee laxity and subjective IKDC score. In addition, no differences were observed for secondary outcomes between groups for differences in ROM and PIF values.

Factors Associated with Trajectories of Physical Activity Over 8 Years in Knee Osteoarthritis.

OBJECTIVE: The aim of the study was to investigate (1) trajectories of physical activity (PA) over 96 months and (2) study to what extent knee pain, muscle strength, physical function, and radiographic disease were associated with PA trajectories in adults with or at risk of knee osteoarthritis (KOA). METHODS: Using the Osteoarthritis Initiative (OAI) database, we described PA trajectories with the Physical Activity Scale for the Elderly (PASE) over 96 months. Knee pain was categorized into three groups: "no pain" [visual numeric pain rating scale (VAS=0)], "little to some pain" (VAS=1-3), or "moderate to severe pain" (VAS ≥ 4). Knee extensor strength was classified into high [>16.21 (men) and >10.82 (women) N/kg/m2 ] and low [12 seconds) and fast (<12 seconds) groups. Radiographic disease was classified as present [Kellgren-Lawrence (KL) ≥2] or absent (KL grade <2) of KOA. RESULTS: Among 3755 participants (age 61.0 ± 9.0 years, body mass index 28.5±4.8 kg/m2 , 58% female), we identified three trajectories: sedentary PA with slow decline (44.3%), low PA with slow decline (41.3%), and high PA with slow decline (14.4%). Poorer gait speed (OR: 2.32; 95% CI: 1.71-3.16), chair stand time (OR: 1.45; 95% CI: 1.07-1.96), and knee extensor strength (OR: 1.35; 95% CI: 1.03-1.76), but not pain or radiographic disease, were associated with PA trajectory of sedentary PA with slow decline. CONCLUSION: Physical function and strength, but not pain and radiographic disease, were associated with a trajectory of decline in PA among adults with or at risk of KOA.

Patient-reported outcomes measurement information system physical function and knee injury and osteoarthritis outcome score relationship on performance measures in people undergoing total knee arthroplasty.

PURPOSE: Primary purpose was to identify relationships between performance-based measures onto both computerized adaptive testing [Physical Function-Computer Adaptive Testing (PF-CAT)] and joint-specific legacy [Knee injury and Osteoarthritis Outcome Score-Activities of Daily Living (KOOS-ADL)] instruments pre- and 12-month post-TKA. METHODS: The PF-CAT and KOOS-ADL were identified as outcomes and performance on the 40-m fast-paced walking test, stair climb test and chair stand test were identified as predictors. Linear regression was used for all comparisons after adjusting for confounders. RESULTS: Sixty-eight people with TKA (56.7% male) were tested. Better scores on the 40-m fast-paced walking (KOOS-ADL, p = 0.02), stair climb (KOOS-ADL, p = 0.05) and chair stand (KOOS-ADL, p < 0.01) associated with better self-reported scores pre-TKA. Better scores on the 40-m fast-paced walking (PF-CAT, p = 0.05; KOOS-ADL, p = 0.01), stair climb (KOOS-ADL, p < 0.01), chair stand (PF-CAT, p < 0.01) and range of motion (KOOS-ADL, p = 0.02) were associated with better self-reported scores 12-month post-TKA. Decrease knee range of motion related to poorer 40-m fast-paced walking (p = 0.01) and stair climb (p = 0.03) scores pre-TKA. Quadriceps weakness related to poorer 40-m fast-paced walking (p = 0.04) score pre-TKA. CONCLUSION: Self-reported instruments are a moderate, but inconsistent surrogate to performance-based measures pre- and post-TKA. Our findings indicate that both self-reported and performance-based measures are necessary to fully characterize physical function and should be used jointly to aid in the recovery analysis of people undergoing TKA.Implications for RehabilitationMonitoring the trajectory of pre- to post-total knee arthroplasty (TKA) physical function is important as it directly relates to mortality, morbidity and poorer quality of life in older adults.Both self-reported and performance-based measures of physical function are used to determine progress in recovery for patients pre- and post- TKA.This study provides evidence that perceived physical function measures are a moderate, but an inconsistent, surrogate to objective physical function measures pre- and post-TKA.Joint specific deficits in knee range of motion and quadriceps strength were weakly associated with deficits in function measures pre-TKA, but no association was observed 12-month post-TKA.Our findings indicate that both self-reported and performance-based measures are necessary to fully characterize physical function and should be used jointly to aid in the complete recovery analysis of people undergoing TKA.

Knee biomechanics and contralateral knee osteoarthritis progression after total knee arthroplasty.

BACKGROUND: Despite the success rate of Total Knee Arthroplasty (TKA), many patients undergo contralateral TKA. It is possible that altered gait mechanics after unilateral TKA play a role in the progression of contralateral OA progression. RESEARCH QUESTION: The purpose of this study was to identify biomechanical predictors of radiographic OA progression in the contralateral (non-surgical) knee after unilateral (primary/initial) TKA. In addition, this study quantified for patients who had contralateral OA progression. METHODS: Biomechanical outcomes were collected 6-24 months after unilateral primary TKA and were used to predict changes in contralateral OA severity at follow-up. Participants were divided into "Progressor" and "Non-Progressor" groups based on changes in Kellgren-Lawrence (KL) OA grade and Joint Space Width (JSW) between baseline and follow-up testing sessions. Biomechanical factors during walking were peak knee adduction moment, knee flexion/extension excursions, knee angle at initial foot contact, and peak knee flexion/extension. Multiple independent t-tests were used to examine the magnitude of differences in biomechanical variables between the groups. Logistic regression was used to examine the association between the biomechanical predictors and change in KL scores and JSW. RESULTS: The mean time between surgery and follow-up x-rays was 8.8 (2.4) years. Of 40 participants, 62.5-78% had contralateral radiographic knee OA progression by follow-up. There were no significant differences in the biomechanical variables between groups. For the regression analysis, none of the biomechanical variables were found to be predictors for contralateral OA progression. SIGNIFICANCE: Although abnormal biomechanics are known risk factors for primary knee OA, it is possible that the mechanisms that result in OA progression of the contralateral limb are different than primary knee OA progression. Future work should evaluate other objective measures of OA progression and determine if cumulative measures of joint loading are related to OA worsening.

The validity and reliability of the OneStep smartphone application under various gait conditions in healthy adults with feasibility in clinical practice.

OBJECTIVE: Primary purpose of this study was to determine the validity and reliability of the OneStep smartphone application in healthy adults. Secondary purpose was to determine the feasibility of measuring gait dysfunction, limitation in spatiotemporal characteristics, longitudinally in patients following total hip or knee arthroplasty. METHODS: First objective, 20 healthy adults (mean age, 42.3 ± 19.7 years; 60% males; mean body mass index, 29.0 ± 5.2 kg/m2) underwent gait analysis under four gait conditions (self-selected gait speed, fixed gait speed at 0.8 m/s, fixed gait speed at 2.0 m/s and self-selected gait speed with dual task) for the validity and reliability of the smartphone to the motion laboratory. Reliability was determined by intraclass correlation coefficients. Validity was determined by Pearson correlations. Agreement was assessed by the Bland-Altman method. Second objective, 12 additional patients with total hip or knee arthroplasty (mean age, 58.7 ± 6.5 years; 58% males; mean body mass index, 28.9 ± 5.8 kg/m2) were measured at 2- and 10 weeks postoperatively. The smartphone application was used to evaluate change in gait dysfunction over time within the patients' own environment using paired t test. RESULTS: The smartphone application demonstrated moderate-to-excellent intraclass correlation coefficients for reliability between-system (ICC range, 0.56-0.99), -limb (ICC range, 0.62-0.99) and -device (ICC range, 0.61-0.96) for gait analysis of healthy adults. Pearson correlations were low-to-very high between methods (r range, 0.45-0.99). Bland-Altman analysis revealed relative underestimation of spatiotemporal variables by the smartphone application compared to the motion system. For patients following total hip or knee arthroplasty, gait analysis using the OneStep application demonstrated significant improvement (p < 0.001, Cohen's d > 0.95) in gait dysfunction between 2- and 10 weeks postoperatively. CONCLUSION: The smartphone application can be a valid, reliable and feasible alternative to motion laboratories in evaluating deficits in gait dysfunction in various environments and clinical settings.

Gait mechanics are influenced by quadriceps strength, age, and sex after total knee arthroplasty.

Although most patients are satisfied with outcomes after total knee arthroplasty (TKA), many retain preoperative altered gait mechanics. Identifying patient characteristics associated with gait mechanics will improve rehabilitation strategies and enhance our understanding of movement disorders. Therefore, the purpose of this study was to identify which patient characteristics are related to gait mechanics in the surgical limb during walking post-TKA. Patient characteristics included age, body mass, sex, quadriceps strength, self-reported function, and knee pain. General linear regression was used to compare patient characteristics associated with gait mechanics, after controlling for gait speed, functional capacity and time from surgery. We tested 191 patients cross-sectionally at 6-24 months after primary, unilateral TKA. Quadriceps weakness in the surgical limb was associated with less peak vertical ground reaction force (PvGRF) (ß = .245, p = .044), knee extension moment (ß = .283, p = .049), and knee extension excursion (ß = .298, p = .038). Older age (ß = .168, p = .050) was associated with less PvGRF. Quadriceps strength in the nonsurgical limb (ß = -.357, p = .021) was associated with greater knee extension excursion in the surgical limb. Females with TKA (ß = -.276, p = .007) had less knee flexion excursion compared to males. Faster gait speed was also associated with greater PvGRF (ß = .585, p < .001), knee extensor moment (ß = .481, p < .001), and knee flexion excursion (ß = .318, p < .001). Statement of Clinical Significance: This study showed quadriceps weakness, slower gait speed, older age and being female were related to altered gait mechanics post-TKA. These findings will help clinicians better educate patients and develop targeted interventions for improving care in patients post-TKA.

Reliability, responsiveness, and validity of handheld dynamometry for assessing quadriceps strength in total knee arthroplasty.

PURPOSE: To determine the reliability, responsiveness, validity, and agreement of handheld dynamometry, relative to electromechanical dynamometry, for assessing quadriceps strength surrounding total knee arthroplasty. METHODS: Fifty-six patients (48% female) undergoing total knee arthroplasty were assessed prior to surgery and at 2 and 6 weeks following surgery. Maximum isometric quadriceps force was assessed at each time point by handheld dynamometry and electromechanical dynamometry. Within-session test-retest reliability was determined by intraclass correlation coefficient (ICC). Standard error of measurement and relative standard error (RSE) values were calculated. Standardized response means were used to describe responsiveness. Pearson's correlations examined construct validity. Agreement was assessed by the Bland-Altman method. RESULTS: Both handheld dynamometry and electromechanical dynamometry demonstrated excellent test-retest reliability (ICC >0.90) and RSE (<15%). Both methods were responsive, with large postoperative standardized response means of 1.57 (handheld dynamometry) and 1.37 (electromechanical dynamometry). Pearson's correlations were moderate to strong. The Bland-Altman analysis revealed underestimation of force by handheld dynamometry, although this effect was diminished in the early postoperative period. CONCLUSIONS: Our results suggest handheld dynamometry is a promising tool for monitoring quadriceps strength in patients pre- and post-total knee arthroplasty.IMPLICATIONS FOR REHABILITATIONThis study provides evidence of high reliability and responsiveness of handheld dynamometry for assessing quadriceps strength throughout a clinically relevant time frame for patients with total knee arthroplasty.There is construct validity of handheld dynamometry for measuring quadriceps strength, with moderate to high correlations between handheld dynamometry and electromechanical dynamometry, both pre- and post-total knee arthroplasty.Rehabilitation professionals should be aware that handheld dynamometry and electromechanical dynamometry do not agree in terms of the force measurement itself; particularly at higher force values, handheld dynamometry underestimates force output relative to electromechanical dynamometry.Overall, this study supports the use of handheld dynamometry for monitoring quadriceps strength in clinical settings for patient with total knee arthroplasty.

Trunk movement compensation identified by inertial measurement units is associated with deficits in physical performance, muscle strength and functional capacity in people with hip osteoarthritis.

BACKGROUND: Trunk movement compensation characterized as ipsilateral trunk lean and posterior rotation with respect to pelvis during stance phase of walking is common in people with hip osteoarthritis and a biomarker of deficits in physical function in older adults. However, the relationship between trunk movement compensation on deficits in physical performance, muscle strength and functional capacity is unknown. METHODS: A cross-sectional study design was used. Two inertial measurement units were used to assess trunk movement compensation during the six-minute-walk-test. Knee extension, knee flexion and hip abduction strength were measured using hand-held dynamometer. Multivariate regression models, controlling for self-reported hip pain, were used to regress trunk movement compensation onto six-minute-walk-test and muscle strength measures. Pairwise t-tests were used to evaluate the difference trunk movement compensation has on functional capacity by comparing the first and last minute of the six-minute-walk-test. FINDINGS: Thirty-five participants (63.3 ± 7.4 years, 57% male, 28.6 ± 4.5 kg/m2) were enrolled. Greater trunk movement compensation was related to poorer six-minute-walk-test (p = 0.03; r = -0.46). Greater hip abduction weakness was related to increased trunk movement compensation in both the sagittal (p = 0.05; r = -0.44) and frontal (p = 0.04; r = -0.38) planes. Participants demonstrated greater frontal plane trunk movement compensation during the last minute compared to the first minute of the six-minute-walk-test (p < 0.01). INTERPRETATION: Trunk movement compensation, identified by inertial measure units, is a clinically relevant measure and has a moderate-to-strong relationship on deficits in physical performance, muscle strength and functional capacity. Inertial measurement units can be used as a practical means of measuring movement quality in the clinical setting.

Longitudinal study of knee load avoidant movement behavior after total knee arthroplasty with recommendations for future retraining interventions.

BACKGROUND: This study aimed to evaluate clinical and biomechanical changes in self-report survey, quadriceps strength and gait analysis over 3- and 6-months post-total knee arthroplasty (TKA) and confirm the immediate effects of two forms of kinetic biofeedback on improving inter-limb biomechanics during a physically demanding decline walking task. METHODS: Thirty patients with unilateral TKA underwent testing at 3- and 6-months following surgery. All underwent self-report survey, quadriceps strength and gait analysis testing. Patients were assigned to one of two types of biofeedback [vertical ground reaction force (vGRF), knee extensor moment (KEM)]. RESULTS: No decrease in gait asymmetry was observed in non-biofeedback trials over time (p > 0.05), despite significant improvements in self-report physical function (p < 0.01, Cohen d = 0.44), pain interference (p = 0.01, Cohen d = 0.68), numeric knee pain (p = 0.01, Cohen d = 0.74) and quadriceps strength (p = 0.01, Cohen d = 0.49) outcomes. KEM biofeedback induced significant decrease in total support moment (p = 0.05, Cohen f2 = 0.14) and knee extensor moment (p = 0.05, Cohen f2 = 0.21) asymmetry compared to using vGRF biofeedback at 6-months. vGRF biofeedback demonstrated significant decrease in hip flexion kinematic asymmetry compared to KEM biofeedback (p = 0.05, Cohen f2 = 0.18) at 6-months. CONCLUSION: Gait compensation remained similar from 3- to 6-months during a task requiring greater knee demand compared to overground walking post-TKA, despite improvements in self-report survey and quadriceps strength. Single session gait symmetry training at 6-month supports findings at 3-month testing that motor learning is possible. KEM biofeedback is more effective at immediately improving joint kinetic loading compared to vGRF biofeedback post-TKA.

A multi-center trial of exercise and testosterone therapy in women after hip fracture: Design, methods and impact of the COVID-19 pandemic.

BACKGROUND: Up to 75% of hip fracture patients never recover to their pre-fracture functional status. Supervised exercise that includes strength training can improve functional recovery after hip fracture. The role of testosterone replacement for augmenting the effects of exercise in older women after hip fracture is unknown. METHODS: The Starting Testosterone and Exercise after Hip Injury (STEP-HI) Study is a 6-month Phase 3 multicenter randomized placebo-controlled trial designed to compare supervised exercise (EX) plus 1% testosterone topical gel, with EX plus placebo gel, and with enhanced usual care (EUC). Female hip fracture patients age ≥ 65 years are being recruited from clinical centers across the United States. Participants are community dwelling and enrolled within 24 weeks after surgical repair of the fracture. The EX intervention is a center-based program of progressive resistance training. The EUC group receives a home exercise program and health education. Participants receive dietary counseling, calcium and vitamin D. The primary outcome is the Six Minute Walk Distance. Secondary outcomes include physical performance measures, self-reported function and quality of life, and dual energy x-ray absorptiometry measures of body composition and bone mineral density. RESULTS: Enrollment, interventions, and follow-up are ongoing. We describe the impact of the coronavirus disease 2019 pandemic on the trial, including modifications made to allow continuation of the interventions and outcome data collection using remote video and audio technology. CONCLUSIONS: Results from the STEP-HI study are expected to have important clinical and public health implications for management of the growing population of hip fracture patients.

Movement asymmetry during low and high demand mobility tasks after dysvascular transtibial amputation.

BACKGROUND: Movement asymmetries between lower limbs are commonly exhibited by adults after transtibial amputation. However, the degree of movement asymmetry between low- and high-demand functional tasks remains unknown. METHODS: Kinematic and kinetic data were collected during overground walking (low-demand) and step ascent (high-demand) tasks for two groups: 1) persons with transtibial amputation and 2) healthy matched peers. Analysis of covariance was used to compare sagittal-plane peak knee moment and joint angle (primary) and hip and ankle moments and joint angles, vertical ground reaction force and impulse (secondary). FINDINGS: Within transtibial amputation group comparisons showed significantly greater between-limb asymmetry in peak knee moment (p < .01), vertical impulse (p < .01), peak vertical ground reaction force (p = .05), peak ankle angle (p < .01) and peak ankle moment (p < .01) with the step ascent task compared to overground walking. The transtibial amputation group had greater between-limb asymmetry during step ascent in peak knee moment (p < .01), vertical impulse (p < .01), peak vertical ground reaction force (p = .04) and peak ankle angle (p < .01) than healthy matched peers. During overground walking, the transtibial amputation group had greater between-limb asymmetry in peak vertical impulse (p = .05) and peak ankle moment (p < .01) than healthy matched peers. INTERPRETATION: Movement asymmetry is increased during step ascent compared to overground walking for adults with transtibial amputation. While the restoration of overground walking is the focus of post-amputation rehabilitation and prosthetic design, higher demand tasks should also be considered to maximize mobility for adults with transtibial amputation.

Benefits of direct patient discharge to outpatient physical therapy after total knee arthroplasty.

Purpose: To investigate the effectiveness of home health physical therapy followed by outpatient physical therapy as compared to patients discharged directly to outpatient physical therapy in improving functional performance, strength/activation and residual knee pain outcomes among patients who received a total knee arthroplasty.Materials and methods: A secondary analysis of longitudinal data in which patients with total knee arthroplasty underwent home health physical therapy or were discharged directly to outpatient physical therapy. Main outcome measures included the stair climb test, timed up and go, 6-min walk test, quadriceps and hamstring strength, quadriceps activation and residual knee pain.Results: Patients referred to home health physical therapy prior to outpatient physical therapy demonstrated significantly greater declines in stair climb test (10.3; 95% CI [6.5, 14.1]; t = 5.41; p < 0.0001), timed up and go (2.0; 95% CI [1.0, 3.0]; t = 4.10; p < 0.0001), 6-min walk (53.8; 95% CI [29.4, 78.2]; t = 4.35; p < 0.0001), quadriceps strength (21.7%; 95% CI [19.3%, 24.9%]; t = 2.53; p = 0.01), hamstring strength (44.7%; 95% CI [43.4%, 45.7%], t = 3.17; p = 0.002) and higher residual knee pain (0.53; 95% CI [0.04, 1.03]; t = 2.17; p = 0.03) 1 month after total knee arthroplasty compared to those referred directly to outpatient physical therapy.Conclusions: These findings suggest that patients discharged directly to outpatient physical therapy had a more rapid recovery 1 month after total knee arthroplasty. Additional research is needed to investigate the potential causal relation between care pathways and clinical outcomes following total knee arthroplasty.Implications for rehabilitationTotal knee arthroplasty, typically performed to alleviate end-stage knee osteoarthritis, is the most commonly performed elective surgery in the United States.Despite improvement in pain, objective measurements of functional performance and strength often remain at preoperative levels one year after total knee arthroplasty.Patients discharged directly to higher intensity outpatient physical therapy have a more rapid recovery after total knee arthroplasty compared with those patients who received two weeks of home health prior to undergoing outpatient physical therapy.

Movement pattern biofeedback training after total knee arthroplasty: Randomized clinical trial protocol.

INTRODUCTION: Total knee arthroplasty (TKA) reduces joint symptoms, but habitual movement compensations persist years after surgery. Preliminary research on movement training interventions have signaled initial efficacy for remediating movement compensations and restoring knee joint loading symmetry during dynamic functional tasks after TKA. The purpose of this clinical trial is to determine if physical rehabilitation that includes movement training restores healthy movement patterns after TKA and reduces the risk of osteoarthritis (OA) progression in the contralateral knee. METHODS/DESIGN: 150 participants will be enrolled into this randomized controlled trial. Participants will be randomly allocated to one of two dose-equivalent treatment groups: standard rehabilitation plus movement training (MOVE) or standard rehabilitation without movement training (CONTROL). Movement training will promote between-limb symmetry and surgical knee loading during activity-based exercises. Movement training strategies will include real-time biofeedback using in-shoe pressure sensors and verbal, visual, and tactile cues from the physical therapist. The primary outcome will be change in peak knee extension moment in the surgical knee during walking, from before surgery to six months after surgery. Secondary outcomes will include lower extremity movement symmetry during functional tasks, physical function, quadriceps strength, range of motion, satisfaction, adherence, contralateral knee OA progression, and incidence of contralateral TKA. DISCUSSION: This study will provide insights into the efficacy of movement training after unilateral TKA, along with mechanisms for optimizing long-term physical function and minimizing negative sequelae of compensatory movement patterns.