title: Correlation between Quadriceps Endurance and Adduction Moment in Medial Knee Osteoarthritis.
abstract: It is not clear whether the strength or endurance of thigh muscles (quadriceps and hamstring) is positively or negatively correlated with the adduction moment of osteoarthritic knees. This study therefore assessed the relationships between the strength and endurance of the quadriceps and hamstring muscles and adduction moment in osteoarthritic knees and evaluated predictors of the adduction moment. The study cohort comprised 35 patients with unilateral medial osteoarthritis and varus deformity who were candidates for open wedge osteotomy. The maximal torque (60°/sec) and total work (180°/sec) of the quadriceps and hamstring muscles and knee adduction moment were evaluated using an isokinetic testing device and gait analysis system. The total work of the quadriceps (r = 0.429, P = 0.037) and hamstring (r = 0.426, P = 0.045) muscles at 180°/sec each correlated with knee adduction moment. Preoperative varus deformity was positively correlated with adduction moment (r = 0.421, P = 0.041). Multiple linear regression analysis showed that quadriceps endurance at 180°/sec was the only factor independently associated with adduction moment (β = 0.790, P = 0.032). The adduction moment of osteoarthritic knees correlated with the endurance, but not the strength, of the quadriceps muscle. However, knee adduction moment did not correlate with the strength or endurance of the hamstring muscle.
authors.affiliation: Department of Orthopaedic Surgery, Korea University College of Medicine, Anam Hospital, Seoul, Korea.
authors.forename: Soon-Hyuck
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Sports Medical Center, Korea University College of Medicine, Anam Hospital, Seoul, Korea.
authors.forename: Jin-Hyuck
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Sports Medical Center, Korea University College of Medicine, Anam Hospital, Seoul, Korea.
authors.forename: Sung-Eun
authors.initials: SE
authors.lastname: Ahn
authors.affiliation: Department of Sports Medical Center, Korea University College of Medicine, Anam Hospital, Seoul, Korea.
authors.forename: Min-Ji
authors.initials: MJ
authors.lastname: Park
authors.affiliation: Department of Orthopaedic Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Dae-Hee
authors.initials: DH
authors.lastname: Lee
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000503:physiopathology*; D020370:Osteoarthritis, Knee / Q000503:physiopathology*; D010807:Physical Endurance / Q000502:physiology*; D052097:Quadriceps Muscle / Q000503:physiopathology*; D016059:Range of Motion, Articular / Q000502:physiology*; D013848:Thigh / Q000503:physiopathology; D019415:Torque