The outcome of anterior cruciate ligament reconstruction in skeletally immature patients with transphyseal tunnels

Abstract

Objective To evaluate the clinical outcomes after transphyseal anterior cruciate ligament (ACL) reconstruction with hamstring autograft in skeletally immature patients. Methods Ten skeletally immature pubescent patients (10 knees) with a mean age of 13.4 years underwent transphyseal ACL reconstruction with hamstring autograft between May 2004 and March 2012. There were 5 males and 5 females. The average duration from injury to surgery was 5.3 months (range 1-12 months). Arthroscopy confirmed ACL rupture in ten knees. Concurrent meniscal surgery was performed in 5 knees. The surgery was conducted via arthroscopically assisted transphyseal reconstruction of the ACL with use of an autogenous quadrupled hamstring tendon graft and fixation devices that do not cross the physes. A protective knee brace was used for 3 months postoperatively with motion limits for the first 2 weeks. The follow-up duration was 6.7 years (range 3-12 years), with evaluation for the following outcomes: physical examination, namely KT-2000 measurements and functional outcome instruments (the International Knee Documentation Committee subjective knee form, the Lysholm scoring, and the Tegner knee activity scale). Radiographs were performed for asymmetrical physeal closure, growth arrest lines and leg-length measurements. Results At the latest follow-up, the mean 2000 IKDC score improved from preoperative 75.1±5.1 to 93.3±3.0, the mean Lysholm score from preoperative 66.1±8.2 to 94.8±3.6 and the mean Tegner score from 4.4±0.8 to 8.5±0.7. All these outcomes had statistically significant difference. Lachman and pivot-shift testing were weekly positive in 3 knees and negative in 7 knees. The mean range of motion of the knee was 140°. Compared with the contralateral knee, no restriction in knee range of motion of 5° or greater was observed in any patient. All patients had normal range of motion. The mean KT-2000 manual maximum side-to-side difference was 1.5±0.7 mm, while that in 3 patients was greater than 2 mm but smaller than 3 mm. No angular deformities were reported. All leg-length measurements were symmetric bilaterally on clinical examination. The mean lateral distal femoral angle was 87.4°±0.6°, and the mean medial proximal tibial angle was 88.3°±0.7°. No patients reported traumatic graft disruption or underwent revision ACL reconstruction, whereas meniscus injury occurred in 3 patients. Conclusion Transphyseal ACL reconstruction with autogenous quadrupled hamstring graft in treating skeletally immature pubescent patients yields satisfied functional outcomes without growth disturbance at a mean follow-up of 6.7 years. Key words: Anterior cruciate ligament; Wounds and injuries; Anterior cruciate ligament reconstruction; Adolescent; Growth plate