Rehabilitation during early postoperative period following total knee arthroplasty using single-joint hybrid assistive limb as new therapy device: a randomized, controlled clinical pilot study

Abstract

Introduction The first weeks after total knee arthroplasty (TKA) are crucial for the functional outcome. To improve knee mobility, a continuous passive motion (CPM) motor rail is commonly used during in-hospital rehabilitation. The single-joint hybrid assistive limb (HAL-SJ) is a new therapy device. The aim of the study was to improve patients’ range of motion (ROM), mobility, and satisfaction using the active-assistive support of the HAL-SJ. Materials and methods Between 09/2017 and 10/2020, 34 patients, who underwent TKA and matched the inclusion criteria, were randomized into study (HAL-SJ) and control (CPM) group. Treatment began after drain removal and was carried out until discharge. Primary outcome parameters were raised pre- and postoperatively and included the Oxford knee score (OKS), visual analog scale (VAS), and acquired range of motion. Furthermore complications caused by the device were recorded. Results OKS increased in both groups postoperatively, but only significantly in the HAL-SJ group. Postoperative pain improved in both groups without significant differences. Flexion improvement was significant in both groups between days 3/7 and 8 weeks postoperatively. We did not encounter any complications related to HAL-SJ. Conclusions In conclusion, use of the HAL-SJ during rehabilitation in the early postoperative period after TKA was safe without disadvantages compared to the control group and seems to have advantages in terms of daily life impairment.

Robotic exoskeletons and total knee arthroplasty: The future of knee rehabilitation and replacement – A meta-analysis

“…In previous studies by Yoshikawa, Goto, Mrotzek, and Kontani, [7,9,11,12] the training device used for rehabilitation was the single-leg version of the HAL used in the Cybernic Voluntary Control mode. This device detects bioelectrical signals generated by the wearer's muscles or floor-reaction-force signals caused by a weight shift.…”

“…In 2022, Yoo et al [8] conducted a meta-analysis involving 6 studies on TKA and 1 on THA. In addition to the articles in Yoo's report, the current study incorporated prospective studies by Cai and Mrotzke [9,13] with 82 and 18 cases, respectively. However, 1 study initially included in Yoo's analysis was excluded from this analysis because of its retrospective design.…”

“…The supplementary image is cited from Mrotzek's study, [9] illustrating leads detecting bioelectric signals (BES) attached to the…”

“…strength. A pooled analysis of 3 studies revealed a significant [9][10][11] reported improvements in extension lag post-TKA. This study showed that the tendency toward improvement in knee extension lag favored using exoskeletons; however, the difference was insignificant (SMD: 3.64, 95% CI: −1.39 to 8.67, P = .16).…”

“…Cai and Mrotzek [9,13] reported the hospital stay of patients who used exoskeletons. This meta-analysis showed that patients who used exoskeletons experienced a significantly shorter hospital stay than the control group patients (SMD: −3.19, 95% CI: −4 to −2.38, P < .00001, Fig.…”