Purpose: Today's patients, who are likely to be younger and more active than ever, have high expectations regarding functional outcome after total hip arthroplasty (THA) and total knee arthroplasty (TKA). Functional outcome is a multi-dimensional construct, which has several measurable aspects, such as 1) actual daily activity in the home situation 2) perceived (problems in) daily functioning, and 3) functional capacity to perform activities in a (semi) laboratory setting. A previous study of our group (de Groot et al, 2008) showed that six months after THA and TKA patients did not have a clinically relevant increase in actual daily activity level in the home situation, despite improvements in perceived daily functioning and functional capacity. This discrepancy might be explained by the relatively short follow-up period of six months: the level of daily activity might be a matter of behaviour, and the change to a more active lifestyle may need a longer time period. Our primary aim was to examine whether the actual daily activity level increased four years after THA and TKA compared to six months postoperative. Our secondary aim was to examine the changes in perceived daily functioning and functional capacity during the same time interval. Methods: The 77 patients (36 hip, 41 knee) who participated in the previous study of de Groot et al. were eligible to participate in this study. Patients were excluded if they have had THA or TKA of the contra lateral side within the past 12 months, have had revision of the primary THA or TKA, or had co-morbidities which affected physical functioning. Of the 77 patients, 21 were excluded based on the above mentioned criteria. Of the 56 eligible patients, 2 patients died, 2 patients were lost to follow up and 8 patients refused to participate. Eventually, 44 patients (23 hip, 21 knee) participated in this study. Actual daily activity was measured with an accelerometry-based Activity Monitor. Perceived physical functioning was measured with the physical functioning subscale of the HOOS/KOOS questionnaire, and functional capacity with the six minutes walk test. Results: The actual daily activity level didn't increase (even a small decrease was seen) four years postoperative compared to six months postoperative (128 minutes vs. 138 minutes activity per 24 hours, respectively; p-value = 0.48). In contrast, both the HOOS/KOOS subscale data (90.4 vs 69.4, p value <0.0001) and the six-minutes-walking test data (568 m vs 404 m, p-value <0.0001) further increased four years postoperative compared to six months postoperative. Conclusions: In contrast to perceived daily functioning and functional capacity, patients did not increase their actual daily activity level four years after THA and TKA compared to six months after surgery. Because of a selection of a relatively healthy patient group in this study these results might be overestimated. So, even on the long term, patients do not adapt a more active lifestyle after THA or TKA.
Vissers, M. M., Bussmann, J. B., Verhaar, J. A., & Reijman, M. (2010). 304 PHYSICAL FUNCTIONING FOUR YEARS AFTER TOTAL HIP AND KNEE ARTHROPLASTY. Osteoarthritis and Cartilage, 18, S136. https://doi.org/10.1016/s1063-4584(10)60331-7