Visualized load-bearing-based robot control system improves early function in femoral neck fracture patients: a randomized controlled trial focusing on outcomes after total hip arthroplasty.

BACKGROUND

After total hip arthroplasty (THA), standing and walking balance are greatly affected in the early recovery period, making it important to increase weight-bearing amount (WBA) on the surgical side. Sometimes, traditional treatment methods may not be sufficient to satisfactorily improve WBA and weight-bearing ratio (WBR) on the surgical side. This study aims to evaluate the effectiveness of a visualized load-bearing-based robot control system in promoting early functional recovery of elderly patients after THA. The system senses lower limb weight and displays it in real-time on the screen to provide visual guidance for weight-bearing.

METHODS

A total of 126 patients with femoral neck fractures who underwent THA from July 2023 to June 2024 were selected and randomly divided into a robot group or a control group. As a result, each group was allocated 63 patients. The robot group used an intelligent weight-bearing robot for rehabilitation, while the control group used conventional walking aids for rehabilitation. Patients underwent rehabilitation for 5-7 days during their hospital stay and then continued with home-based rehabilitation after discharge. All measurements were taken one month after surgery to analyze the impact of the two rehabilitation methods on early postoperative function. The main outcome measures included VAS scores, hip joint extension-flexion range of motion (ROM), Harris scores, time for straight leg raising, and 3-minute walking distance.

RESULTS

There were no statistically significant differences between the two groups in terms of age, gender, surgical time, blood loss, length of hospital stay, time to weight-bearing, and preoperative VAS score (P > 0.05). At the 1-month postoperative follow-up, the robot group demonstrated superior outcomes compared to the control group in terms of VAS score, ROM of the hip joint, Harris score, time for straight leg raising, and 3-minute walking distance, with statistically significant differences (P < 0.05). The WBR for the first postoperative weight-bearing on the operated side of the patient was (36.9 ± 14.0)%; it was (49.1 ± 11.1)% in the second week, (61.9 ± 8.4)% in the third week, (74.7 ± 5.8)% in the fourth week, (87.5 ± 4.0)% in the fifth week, and (100.0 ± 0.0)% in the sixth week. There were significant differences in WBR between every two postoperative weeks (p < 0.05). The WBR on the operated side of all patients reached 100% by the end of the sixth week postoperatively.

CONCLUSION

This study demonstrates that a robot control system based on visualized load-bearing can effectively enhance early functional recovery after THA in a short postoperative period, making it a valuable intelligent rehabilitation system. This is beneficial for improving the ability to perform daily activities after THA and may contribute to optimizing the effectiveness of medical care.

TRIAL REGISTRATION: This study has been registered in national medical research registration and filing information system of China, www.medicalresearch.org.cn , Trail registration number: MR-35-24-038086.