Effects of Isokinetic Training After Knee Chondroplasty With BioCartilage on Hamstrings-to-Quadriceps Ratio: A Case Study

Abstract

Background: This case study examined the effects of a 12-week isokinetic training program after knee arthroscopy with chondroplasty of the medial femoral condyle using BioCartilage on the absolute and normalized hamstrings-to-quadriceps ratio (HTQ) in a female. Methods: One female (age = 30 years, height = 174.90 cm, body mass = 92.56 kg) underwent a 12-week isokinetic training program consisting of 3 days/week. Maximal voluntary isometric contractions (MVIC) and isokinetic knee extension and flexion at 60, 120, 180, 240, and 300°·s⁻¹ were tested before and after the 12-week isokinetic training program on an isokinetic dynamometer. Cross-sectional area (CSA) of the quadriceps and hamstrings was assessed with B-mode ultrasound. Results: HTQ CSA increased from pre- to post-test by approximately 2.29% in the operative and 1.07% in the nonoperative leg. Absolute and normalized HTQ on the operative leg decreased at MVIC, 60, and 180°·s⁻¹, and HTQ on the nonoperative leg decreased at 60, 120, and 240°·s⁻¹. Conclusions: Within the first 12 weeks following post-operative rehabilitation and medical clearance after knee chondroplasty with BioCartilage, isokinetic training was accompanied by increased HTQ CSA in both legs, while HTQ increased at moderate and fast velocities on the operative leg and at isometric and very fast velocities on the nonoperative leg, although all changes were below the minimal detectable change (MDC). This case suggests that isokinetic training may be a useful rehabilitation tool alongside traditional physical therapy.