Biomechanics of patellar tendon autograft for reconstruction of the anterior cruciate ligament in the goat: Three-year study

✍ Scribed by Gabriel Y. Ng; Barry W. Oakes; Owen W. Deacon; Iain D. McLean; Douglas Lampard

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 705 KB
• Volume: 13
• Category: Article
• ISSN: 0736-0266
• DOI: 10.1002/jor.1100130416

✦ Synopsis

Abstract

This study examined the biomechanics of anterior cruciate ligament‐patellar tendon autografts for as long as 3 years after surgery. Twenty‐seven adult female goats were tested; four served as controls and the others received an autograft to the right knee with each left knee serving as an additional control. The animals with grafts were tested at 0 week (n = 4), 6 weeks (n = 4), 12 weeks (n = 4), 24 weeks (n = 3), 1 year (n = 5), and 3 years (n = 3) after surgery. The anteroposterior laxity of the knee joint, load‐relaxation, and structural and material properties of the graft were tested. The anteroposterior laxity was significantly greater than that of the controls for all groups except at 3 years. Load‐relaxation was greater than that of the control anterior cruciate ligaments, but in the 1 and 3‐year grafts load‐relaxation was less than that of the patellar tendons with 5 minutes of sustained loading. Between 12 and 52 weeks, the stiffness and modulus of the grafts increased 3‐fold, but the improvement was slow afterward. At 3 years, the strength and stiffness of the grafts were 44 and 49% those of the control ligaments, respectively; the modulus was 37 and 46% that of the control anterior cruciate ligaments and patellar tendons, respectively. The persistent inferior mechanical performance at 3 years suggests that anterior cruciate ligament grafts may never attain normal strength.