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

Abstract

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 Rehabilitation Monitoring 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.