Victoria Ko

The six-minute walk test is an excellent predictor of functional ambulation after total knee arthroplasty

BackgroundThe Six-minute walk (6MW) and Timed-Up-and-Go (TUG) are short walk tests commonly used to evaluate functional recovery after total knee arthroplasty (TKA). However, little is known about walking capacity of TKA recipients over extended periods typical of everyday living and whether these short walk tests actually predict longer, more functional distances. Further, short walk tests only correlate moderately with patient-reported outcomes. The overarching aims of this study were to compare the performance of TKA recipients in an extended walk test to healthy age-matched controls and to determine the utility of this extended walk test as a research tool to evaluate longer term functional mobility in TKA recipients.MethodsThe mobility of 32 TKA recipients one year post-surgery and 43 healthy age-matched controls were assessed using the TUG, 6MW and 30-minute walk (30MW) tests. The latter test was repeated one week later. Self-reported function was measured using the WOMAC Index and a physical activity questionnaire.Results30MW distance was significantly shorter amongst TKA recipients (mean 2108 m [95% CI 1837 to 2381 m]; Controls 3086 m [2981 to 3191 m], P < 0.001). Test-retest repeatability was high (ICC = 0.97, TKA; 0.96, Controls). Amongst TKA recipients, the 30MW distance correlated strongly with the shorter tests (6MW, r = 0.97, P < 0.001; TUG, r = −0.82, P < 0.001). Multiple regression modeling found 6MW distance to be the only significant predictor (P < 0.001) of 30MW distance, explaining 96% of the variability. The TUG test models were moderate predictors of WOMAC function (55%) and physical activity (36%) and were stronger predictors than 6MW and 30 MW tests.ConclusionsThough TKA recipients are able to walk for 30 minutes one year post-surgery, their performance falls significantly short of age-matched norms. The 30MW test is strongly predicted by 6MW test performance, thus providing strong construct validity for the use of the 6MW test in the TKA population. Neither a short nor long walk test is a strong predictor of patient-reported function after TKA.

One-to-One Therapy Is Not Superior to Group or Home-Based Therapy After Total Knee Arthroplasty A Randomized, Superiority Trial

BACKGROUND The aim of this study was to determine whether center-based, one-to-one physical therapy provides superior outcomes compared with group-based therapy or a simple monitored home-based program in terms of functional and physical recovery and health-related quality of life after total knee arthroplasty. METHODS Patients awaiting primary total knee arthroplasty at two Sydney metropolitan hospitals were enrolled into this prospective, randomized, superiority trial preoperatively. At two weeks postoperatively, participants were randomly allocated to one of three six-week treatment programs (twelve one-to-one therapy sessions, twelve group-based therapy sessions, or a monitored home program) with use of a computer-generated sequence. Self-reported outcomes (Oxford Knee Score, Western Ontario and McMaster Universities Osteoarthritis Index pain and function subscales, and Medical Outcomes Study 12-Item Short-Form Survey) and performance-based functional outcomes were measured over twelve months postoperatively by a blinded assessor. The primary outcome was knee pain and function measured with use of the Oxford Knee Score at ten weeks postoperatively. Intention-to-treat analysis was conducted. RESULTS Two hundred and forty-nine patients (eighty-five who had one-to-one therapy, eighty-four who had group-based therapy, and eighty who were in the monitored home program) were randomized and 233 were available for their one-year follow-up assessment. Participants who received one-to-one therapy did not have a superior Oxford Knee Score at week ten compared with those who received the alternative interventions; the median score was 32 points for the one-to-one therapy group, 36 points for the group-based therapy group, and 34 points for the monitored home program group (p = 0.20). Furthermore, one-to-one therapy was not superior compared with group-based therapy or monitored home program in improving any of the secondary outcomes across the first postoperative year. No adverse events were associated with any of the treatment arms. CONCLUSIONS One-to-one therapy does not provide superior self-reported or performance-based outcomes compared with group-based therapy or a monitored home program, in the short term and the long term after total knee arthroplasty. LEVEL OF EVIDENCE Therapeutic level I. See Instructions for Authors for a complete description of levels of evidence.

Is discharge knee range of motion a useful and relevant clinical indicator after total knee replacement? Part 2.

OBJECTIVE Knee range of motion (ROM) at discharge from acute care is used as a clinical indicator following total knee replacement (TKR) surgery. This study aimed to assess the clinical relevance of this indicator by determining whether discharge knee ROM predicts longer-term knee ROM and patient-reported knee pain and function. METHODS A total of 176 TKR recipients were prospectively followed after discharge from acute care. Outcomes assessed included knee ROM and Oxford knee score post rehabilitation and 1 year post surgery. Discharge ROM and other patient factors were identified a priori as potential predictors in multiple linear regression modelling. RESULTS A total of 133 (76%) and 141 (80%) patients were available for follow-up post rehabilitation [mean postoperative week 8.1 (SD 2.7)] and at 1 year [mean postoperative month 12.1 (SD 1.4)], respectively. Greater discharge knee flexion was a significant (P < 0.001) predictor of greater post-rehabilitation flexion but not 1-year knee flexion (P < 0.083). Better discharge knee extension was a significant predictor of better post-rehabilitation (P = 0.001) and 1-year knee extension (P = 0.013). Preoperative Oxford score and post-rehabilitation knee flexion independently predicted post-rehabilitation Oxford score, and gender predicted 1-year Oxford score. Discharge ROM did not significantly predict Oxford score in either model. CONCLUSION The finding that early knee range predicts longer-term range provides clinical evidence favouring the relevance of discharge knee ROM as a clinical indicator. Although longer-term patient-reported knee pain and function were not directly associated with discharge knee ROM, they were associated with ROM when measured concurrently in the sub-acute phase. No causal effect has been demonstrated, but the findings suggest it may be important for physiotherapists to maximize range in the early and sub-acute periods.

Tourniquet application only during cement fixation in total knee arthroplasty: a double-blind, randomized controlled trial

Background:  The functional benefits of tourniquet application for short periods compared with standard duration applications during total knee arthroplasty surgery have not been well explored. We aimed to compare functional outcomes between tourniquet application of short duration (during cement fixation only) and tourniquet application of longer duration (from skin incision to just after cement fixation).

Heart rate response and factors affecting exercise performance during home‐ or class‐based rehabilitation for knee replacement recipients: lessons for clinical practice

OBJECTIVES Patients undergoing total knee replacement (TKR) are typically de-conditioned and manifest medical co-morbidities associated with a lack of fitness. Consequently, an argument exists for rehabilitation programmes to target cardiovascular fitness. Doubt exists, however, as to the capacity of TKR recipients to exercise intensely and effectively. This preliminary study aimed to: (1) determine whether patients participating in a home- or class-based exercise programme can exercise in their heart rate (HR) training zone, and (2) identify confounding factors influencing performance. METHODS A mixed method study nested within a randomized trial was undertaken. Forty-two people (mean age 70 years; 23 women) randomized to commence a 6-week group-based (GRP) or monitored home-based programme (MHP) 2 weeks post surgery participated. Assessments were undertaken weeks 5 (GRP and MHP) and 8 (GRP only) post surgery. HR and participant perceived exertion (PE, 0-10 point scale) captured exercise intensity. Qualitative description using triangulation of informant sources identified factors influencing exercise performance. RESULTS For both programmes, attainment of training HR was almost universal (93% or more), average time spent above the training HR exceeded 30 minutes, and PE indicated moderate exertion (5/10). Individual inconsistency in time spent above the training HR was evident between testing weeks in GRP participants. Therapist skill and focus, and patient co-morbidity, knee pain and stiffness and willingness were confounders of performance. CONCLUSION TKR recipients participating in exercise programmes can exercise moderately hard indicating a potential for rehabilitation to improve cardiovascular fitness. Whether individual fitness actually improves likely depends in part on therapist recognition of key modifiable factors. It is recommended that therapists use these observations to inform practice so patients extract the most benefit from their rehabilitation.Objectives  Patients undergoing total knee replacement (TKR) are typically de-conditioned and manifest medical co-morbidities associated with a lack of fitness. Consequently, an argument exists for rehabilitation programmes to target cardiovascular fitness. Doubt exists, however, as to the capacity of TKR recipients to exercise intensely and effectively. This preliminary study aimed to: (1) determine whether patients participating in a home- or class-based exercise programme can exercise in their heart rate (HR) training zone, and (2) identify confounding factors influencing performance. Methods  A mixed method study nested within a randomized trial was undertaken. Forty-two people (mean age 70 years; 23 women) randomized to commence a 6-week group-based (GRP) or monitored home-based programme (MHP) 2 weeks post surgery participated. Assessments were undertaken weeks 5 (GRP and MHP) and 8 (GRP only) post surgery. HR and participant perceived exertion (PE, 0–10 point scale) captured exercise intensity. Qualitative description using triangulation of informant sources identified factors influencing exercise performance. Results  For both programmes, attainment of training HR was almost universal (93% or more), average time spent above the training HR exceeded 30 minutes, and PE indicated moderate exertion (5/10). Individual inconsistency in time spent above the training HR was evident between testing weeks in GRP participants. Therapist skill and focus, and patient co-morbidity, knee pain and stiffness and willingness were confounders of performance. Conclusion  TKR recipients participating in exercise programmes can exercise moderately hard indicating a potential for rehabilitation to improve cardiovascular fitness. Whether individual fitness actually improves likely depends in part on therapist recognition of key modifiable factors. It is recommended that therapists use these observations to inform practice so patients extract the most benefit from their rehabilitation.

IS THERE A ROLE FOR REHABILITATION STREAMING FOLLOWING TOTAL KNEE ARTHROPLASTY? PRELIMINARY INSIGHTS FROM A RANDOMIZED CONTROLLED TRIAL

OBJECTIVE To determine whether total knee arthroplasty recipients demonstrating comparatively poor mobility at entry to rehabilitation and who received supervised therapy, had better rehabilitation outcomes than those who received less supervision. DESIGN Retrospective analysis of randomized trial data. PATIENTS Total knee arthroplasty participants randomized to supervised (n = 159) or home-based therapy (n = 74). METHODS Participants were dichotomized based on mean target 6-min walk test (6MWT) pre-therapy (second post-surgical week). Absolute and change in 6MWT and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain and Function subscales amongst low performers in the supervised (n = 89) and unsupervised (n = 36) groups were compared, as were high performers in the supervised (n = 70) and unsupervised (n = 38) groups. RESULTS Low performers in the unsupervised compared with the supervised group demonstrated significantly poorer 6MWT scores (absolute δ = 8.5%, p = 0.003; change δ = 8.1%, p = 0.007) when therapy ceased (10 weeks post-surgery). No differences in 6MWT were observed between the high performing subgroups or in the recovery of WOMAC subscales between any subgroups. CONCLUSION Individuals manifesting comparatively poor mobility at the commencement of physiotherapy may recover their mobility, but not perceived function, more quickly if streamed to supervised therapy.