A Smartwatch Paired With A Mobile Application Provides Postoperative Self-Directed Rehabilitation Without Compromising Total Knee Arthroplasty Outcomes: A Randomized Controlled Trial.

Background: Self-directed rehabilitation (SDR) after total knee arthroplasty (TKA) has not been traditionally recommended. The purpose of this study was to determine if there was an impact on postoperative outcomes with the use of an SDR program after primary TKA.

Methods: In this prospective, randomized, multicenter, controlled trial, we paired a smartwatch with a mobile application, providing an SDR program after TKA. Three groups were examined in this level I study: (1) control group (formal physical therapy [PT]), (2) high exercise compliance group, and (3) low exercise compliance group. Patient-reported outcome measures (PROMs) of knee injury and osteoarthritis outcome scores, joint replacement (KOOS, JR), and EuroQol five-dimension five-level (EQ-5D-5L) along with range of motion (ROM) and manipulation rates were evaluated.

Results: Three hundred thirty-seven patients were enrolled in two groups with 184 in the control group and 153 in the study groups (90 in the high-compliance group and 63 in the low-compliance group). The KOOS, JR score was statistically lower in the low-compliance group in net change from preoperative scores at 3 months (P = .046) and 6 months (P = .032) than that in the control group; difference was noted at 6 months for the high-compliance group, P = .036. However, these did not meet the threshold of 8.02 units for KOOS JR minimal clinically important difference. No differences were seen in PROMs at other time intervals and in manipulation rates or ROM.

Conclusion: Postoperative outcomes including manipulation under anesthesia, ROM, and PROMs were not different when a smartwatch paired with a self-directed PT mobile application was compared with traditional formal PT. Surgeons can consider this an appropriate alternative to traditional PT programs after TKA.