Discussion
knee arthroplasty, pain
MINOR, STS
The aim of this prospective randomized controlled pilot study was to assess the effect of a digital-assisted group therapy concept on subjective outcomes, strength of the lower extremities, and functional mobility as well as gait parameters in patients with total hip and knee arthroplasty at three- and six-months follow-up. The main findings were: (i) the IG received significantly more therapy sessions than the CG; (ii) at three-months follow-up, the WOMAC stiffness score and the CV of gait velocity were higher in the IG compared to CG; (iii) at six-months follow-up, quality of life (i.e., EQ-5D index, EQ-5D health status) was higher in the IG along with a lower pain, stiffness, and better physical function (WOMAC dimensions) as well as TUG performance. Moreover, the CV of gait velocity was significantly higher in the IG compared to CG. When accounting for the differences in the number of therapy session in the statistical analyses for the six-months follow-up, (iv) the IG had still a higher EQ-5D index and EQ-5D health status as well as a lower WOMAC pain score. Moreover, step length and the CV of gait velocity were higher in the IG compared to the CG, when the results were adjusted for the number of therapy sessions.According to the verbal inquiry, the IG received significantly more therapy sessions during the first six postoperative months compared to the CG. In general physiotherapy proved to be effective for improving clinical outcomes after total hip and knee arthroplasty [The results of the present study revealed only small differences in several outcomes between groups at three-months follow-up. These data collectively indicate that the digital-assisted rehabilitation approach is in short term after total knee and hip arthroplasty similarly effective as the standard physiotherapy that depends on the prescription of the supervising physician. This is in agreement with Wijnen et al. showing comparable functional outcomes after twelve weeks of app-based therapy at home and standardized outpatient rehabilitation [Despite the minor differences in all outcomes between groups at three-months follow-up, quality of life (i.e., EQ-5D index, EQ-5D health status) was higher in the IG at six-months follow-up along with a lower pain, stiffness, and better physical function (WOMAC dimensions) as well as TUG performance. Given that the IG received more therapy sessions, these results can be partly explained by the higher training volume. However, when accounting for the number of therapy sessions in the statistical analyses, the IG had still a higher quality of life (i.e., EQ-5D index, EQ-5D health status), a lower WOMAC pain score, and an increased step length. These data indicate that the novel digital-assisted therapy concept might induce better mid- and long-term outcomes compared to the standard physiotherapy in Germany. Although not directly transferable, a recently published systematic review on the comparison of telerehabilitation and face-to-face rehabilitation after total knee arthroplasty points in the same direction. The authors have found that telerehabilitation induced a similar pain relief, a better WOMAC score as well as higher range of motion in extension and quadriceps muscle strength [Overall both groups improved the STS and TUG performance during the rehabilitation process as shown by previous studies [The conducted gait analyses revealed an increase in step length for both groups but a higher step length in the IG six months after total hip and knee arthroplasty, when adding the number of therapy sessions to the statistical model. Previously published studies revealed increased stride or step length during the rehabilitation process after total knee or hip replacement, but patients did not reach stride or step length of a healthy population even one year after surgery [There are some limitations in our pilot study. The sample size of 26 is relatively small and therefore only small group differences were expected. However, positive trends in the IG were observed indicating an equal and partially higher effectiveness in comparison to the standard physiotherapy in Germany following hip or knee replacement. Moreover, two dropouts were reported in the IG, but those occurred prior to the start of the intervention. During the intervention process no study participant dropped out, suggesting a high adherence of patients despite the high time expenditure of therapy twice a week for several months. Although no significant group differences were found regarding anthropometric measurements, sex, or affected joint (hip or knee), even small differences could have affected the outcome of this study. We addressed this limitation by adding those variables as covariates to the ANCOVA. Based on the post-hoc sample size calculations, a full-sized randomized controlled trial would require at least 75 participants to be enrolled to reach a power of 80% for quality of life (EQ-5D) six months postoperatively. Furthermore, future studies should more accurately verify the time and cost efficiency of the novel digital-assisted and individualized group therapy concept.