Effects of Electromyographic Biofeedback Training After Meniscectomy on Quadriceps Strength and Health Related Quality of Life: A Randomized Controlled Trial

Background: Meniscal tears are common knee injuries often treated with arthroscopic partial meniscectomy (APM), though its superiority over conservative treatment is debated. Postoperative quadriceps weakness, especially in the vastus medialis oblique (VMO), can impair knee function due to muscle imbalances. Electromyographic biofeedback (EMG BFB) is recommended to enhance muscle activation and rebalance the VMO and vastus lateralis (VL). While EMG BFB may improve strength and functionality by providing real-time muscle activity feedback, evidence of its effectiveness in strength and health related quality of life (HRQoL) over conventional exercise remains inconclusive. Objective: Assess whether a physiotherapy program utilizing EMG BFB offers greater improvements in quadriceps strength and HRQoL compared to a conventional physiotherapy program (CPT) in patients undergoing APM. Methods: A total of 33 participants who had undergone APM were divided into an experimental group (EG) (n = 16, mean age 40.00 ± 12.25 years; 75% male, 25% female) and a control group (CG) (n = 17, mean age 47.12 ± 11.23 years; 52.9% male, 47.1% female) for a four-week physiotherapy program. EG did a CPT with EMG BFB and CG a CPT program. Strength was measured with a handheld dynamometer while executing maximum voluntary isometric contractions (MVIC) at knee flexion angles of 90º and 45º, and HRQoL with the KOOS-QoL questionnaire. Results: After two weeks EG had greater quadriceps strength (MVIC 90º, p = 0.048) and (MVIC 45º, p = 0.016) than CG. The strength difference between groups continued to increase until the fourth week (MVIC 90º, p = 0.014) and (MVIC 45º, p = 0.006). Health related quality of life remained without significant differences throughout the trial. Conclusion: Integrating electromyographic biofeedback into a standard physiotherapy program following arthroscopic partial meniscectomy effectively enhances quadriceps strength levels allowing improved training progression and an enhanced rehabilitation process.