Immediate Postoperative Biofeedback with an Insole Device in Unilateral TKA

Background: After unilateral total knee arthroplasty (TKA), patients place more weight on the nonsurgical limb than the surgical limb. The objective of this study was to determine the possibility of providing live biofeedback during early recovery of patients undergoing unilateral TKA and to determine the necessary sample size for future trials. Methods: Twenty patients with unilateral TKA were randomized into two groups: a feedback group and a control group. Inclusion criteria included no contralateral knee pain and aid-free walking before surgery. There were 8 patients in the feedback group and 10 in the control group. Compliance with the recommended training was 91%. The feedback group trained with an insole device for 15 min a day for 4 weeks, along with normal physiotherapy. The control group received normal physiotherapy only. Gait parameters were recorded on level ground at two and six weeks. The primary outcome was the percent loading rate. The secondary outcomes included gait speed, cadence, percent peak force, and pain. Results: Patients within the feedback group showed a small, non-significant trend toward a higher precent load rate at 6 weeks compared to the control group in level walking (p = 0.92). Conclusions: Our findings indicate that live biofeedback on a gait parameter, like percent load rate, can be provided by the mentioned system and may support immediate changes in gait parameters. The compliance of 91% with training and no reported adverse events indicates that the system was easy to use. Following TKA, there may be a potential exploratory use of mobile, real-time biofeedback to help address gait abnormalities and accelerate rehabilitation. This clinical trial was registered at clinicaltrials.gov (Identifier: NCT03673293) on 14 September 2018. This study was conducted in accordance with the Declaration of Helsinki and approved by the institutional review board of the University of Utah (IRB_00110935) on 10 September 2018.