# EFFECT OF EARLY HYBRID ASSISTIVE LIMB ASSISTED REHABILITATION ON FUNCTIONAL OUTCOMES AND PATIENT SATISFACTION AFTER TOTAL KNEE ARTHROPLASTY: A RANDOMIZED CONTROLLED TRIAL

## TL;DR

Using a robotic device early after knee replacement surgery may improve recovery and quality of life without increasing pain or swelling.

## Contribution

This study shows early use of the single-joint hybrid assistive limb improves functional outcomes after total knee arthroplasty.

## Key findings

- The early hybrid assistive limb group had significantly better quality of life scores at 12 months.
- Recovery time for knee extension was faster in the early hybrid assistive limb group.
- Knee flexion range of motion improved more in the early hybrid assistive limb group at 1 week.

## Abstract

Early rehabilitation within 4 h following total knee arthroplasty involves passive exercise with manual therapy.

The aim was to determine the beneficial effects of the single-joint hybrid assistive limb for rehabilitation within 4 h after total knee arthroplasty.

This single-blinded randomized controlled trial included 68 participants who underwent primary total knee arthroplasty for knee osteoarthritis and were assigned to the early single-joint hybrid assistive limb (n = 22), HAL-SJ (n = 23), and control (n = 23) groups.

The Knee Injury and Osteoarthritis Outcome Score quality of life (p = 0.007) scores of the early single-joint hybrid assistive limb group showed significantly higher values than the control groups at 12 months. The recovery time for extension lag was significantly improved in the early single-joint hybrid assistive limb group compared with the single-joint hybrid assistive limb (p = 0.006) and control (p < 0.001) groups. Additionally, the knee flexion range of motion of the early single-joint hybrid assistive limb group showed significantly higher values than the single-joint hybrid assistive limb (p = 0.029) and control (p = 0.031) groups at 1 week.

Early single-joint hybrid assistive limb rehabilitation may improve patient-reported quality of life at 12 months without exacerbating postoperative pain or swelling. These results suggest that the single-joint hybrid assistive limb may be a feasible adjunct to early postoperative rehabilitation after total knee arthroplasty, while further studies are required to clarify its clinical relevance and long-term benefits.

This study investigated whether using a wearable robotic device called the single-joint hybrid assistive limb can improve early rehabilitation after total knee arthroplasty. A total of 68 patients were divided into 3 groups, with 1 group starting hybrid assistive limb therapy within 4 h after surgery. The early hybrid assistive limb group showed better quality of life 12 months postoperatively compared with the other groups. They also recovered knee extension and range of motion more quickly. These results suggest that starting with the hybrid assistive limb soon after surgery may lead to faster and better recovery in patients undergoing total knee arthroplasty. These results suggest that HAL-SJ may be a feasible adjunct to early postoperative rehabilitation after total knee arthroplasty, while further studies are required to clarify its clinical relevance and long-term benefits.