title: Quantitative evaluation of knee instability and muscle strength after anterior cruciate ligament reconstruction using patellar and quadriceps tendon.
abstract: Anterior cruciate ligament reconstruction using an autologous graft harvested from the central one-third of the patellar and quadriceps tendon was performed in 65 knees of 65 patients who were followed from 3 to 7 years. Mean anterior laxity of both knees was measured before and after surgery in each patient using the Styker Knee Laxity Tester. At 30 degrees of knee flexion, 58 patients (89%) had differences of less than 2.5 mm between the operated and unoperated knees. Quadriceps strength was measured with the Cybex II and was less than 50% of the uninjured knee at 3 months after surgery. In men, quadriceps strength returned to 78% of normal at 1 year and 85% at final followup. These values were equal to the preoperative level. In women, the quadriceps strength at final followup was 70%, significantly lower than preoperative strength. Hamstring strength recovered to equal the normal strength. Although anterior cruciate ligament reconstruction using one-third of the patellar and quadriceps tendon achieves stability, postoperative quadriceps weakness is a disadvantage. This weakness may be caused by impairment of the knee extensor mechanism resulting from harvesting the graft. We do not currently recommend this technique for anterior cruciate ligament reconstruction.
authors.affiliation: Department of Orthopaedic Surgery, Hokkaido University School of Medicine, University Hospital, Sapporo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yasuda
authors.forename: Y
authors.initials: Y
authors.lastname: Ohkoshi
authors.forename: Y
authors.initials: Y
authors.lastname: Tanabe
authors.forename: K
authors.initials: K
authors.lastname: Kaneda
mesh_terms: D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000503:physiopathology / Q000601:surgery*; D005069:Evaluation Studies as Topic; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology / Q000601:surgery*; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D009132:Muscles / Q000502:physiology*; D011446:Prospective Studies; D016059:Range of Motion, Articular / Q000502:physiology; D013710:Tendons / Q000637:transplantation*; D013848:Thigh / Q000601:surgery; D014182:Transplantation, Autologous