Dae-Hee Lee1, Jin-Hyuck Lee2, Hye-Jin Jeong2, Seok-Joo Lee2. 1. Department of Orthopaedic Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. ; Department of Sports Medical Center, Korea University College of Medicine, Seoul, Korea. 2. Department of Sports Medical Center, Korea University College of Medicine, Seoul, Korea.
Abstract
PURPOSE: The purpose of this study was to evaluate the quadriceps and hamstring muscle strength and hamstring-to-quadriceps (HQ) ratio, as well as the relationships of these parameters with dynamic balance, in patients with anterior cruciate ligament (ACL) rupture. MATERIALS AND METHODS: We compared 25 patients diagnosed with chronic unilateral ACL tears and 25 age-matched healthy volunteers. The maximal torque of the quadriceps and hamstring and dynamic balance were measured. RESULTS: Although the isokinetic maximal peak torques were about 50% lower in the quadriceps (57%, p<0.001) and hamstring (56%, p=0.001) muscles in the chronic ACL tear group than in the control group, their HQ ratios were similar (56%±17% vs. 58%±6%, p=0.591). HQ ratio was significantly correlated with anterior-posterior stability index (r=-0.511, p=0.021) and overall stability index (r=-0.476, p=0.034) in control group, but these correlations were not observed in chronic ACL tear group. CONCLUSIONS: Thigh muscle strength was about 50% lower in the chronic ACL tear group than in the control group, but the HQ ratio was similar. The dynamic balance of the knee was not influenced by thigh muscle strength but was influenced by HQ ratio in healthy young individuals. However, HQ ratio was not correlated with dynamic knee balance in chronic ACL tear patients.
PURPOSE: The purpose of this study was to evaluate the quadriceps and hamstring muscle strength and hamstring-to-quadriceps (HQ) ratio, as well as the relationships of these parameters with dynamic balance, in patients with anterior cruciate ligament (ACL) rupture. MATERIALS AND METHODS: We compared 25 patients diagnosed with chronic unilateral ACL tears and 25 age-matched healthy volunteers. The maximal torque of the quadriceps and hamstring and dynamic balance were measured. RESULTS: Although the isokinetic maximal peak torques were about 50% lower in the quadriceps (57%, p<0.001) and hamstring (56%, p=0.001) muscles in the chronic ACL tear group than in the control group, their HQ ratios were similar (56%±17% vs. 58%±6%, p=0.591). HQ ratio was significantly correlated with anterior-posterior stability index (r=-0.511, p=0.021) and overall stability index (r=-0.476, p=0.034) in control group, but these correlations were not observed in chronic ACL tear group. CONCLUSIONS: Thigh muscle strength was about 50% lower in the chronic ACL tear group than in the control group, but the HQ ratio was similar. The dynamic balance of the knee was not influenced by thigh muscle strength but was influenced by HQ ratio in healthy young individuals. However, HQ ratio was not correlated with dynamic knee balance in chronic ACL tear patients.
Authors: A D Georgoulis; S Ristanis; C O Moraiti; N Paschos; F Zampeli; S Xergia; S Georgiou; K Patras; H S Vasiliadis; G Mitsionis Journal: Orthop Traumatol Surg Res Date: 2010-10-29 Impact factor: 2.256