[Arthroscopically assisted internal fixation of avulsion fractures of the anterior cruciate ligament during childhood and adolescence].

Objective: Minimally invasive reduction and internal fixation of anterior tibial spine and anterior cruciate ligament (ACL) without harming knee joint cartilage and physis of the proximal tibia.

Indications: Anterior tibial spine fractures type II-IV according to Meyers/McKeever.

Contraindications: ACL tears. Fractures of the tibial plateau. Fractures involving the growth plate (Aitken I-III).

Surgical Technique: 1. Diagnostic arthroscopy and drainage of the knee joint. Search for additional injuries (menisci, knee joint cartilage, collateral ligaments, posterior cruciate ligament). 2. Arthroscopy-assisted reduction of anterior tibial spine fragment. 3. Epiphyseal internal fixation with Kirschner wires or cannulated screws according to fragment size.

Postoperative Management: Full weight bearing as tolerated after wound healing (day 7 after surgery) in 20 degrees of knee flexion (orthesis or ankle-sparing cast tutor). X-rays postoperatively and after 3 and 6 weeks. Passive and active physiotherapy (extension and flexion without weight bearing) 3-4 weeks postoperatively according to patient's age, weight and compliance. Weight bearing in knee flexion (stairs) 6-8 weeks postoperatively.

Results: 19 patients were treated from 2001 to 2005 at an age of 7-14 years. All patients achieved free range of motion without pain or growth disturbances. Three patients developed slight joint laxity (anterior drawer test) which did not affect mobility, sports performance, joint surface or menisci on clinical evaluations conducted at least 1 year postoperatively. One patient had bony healing of the tibial spine in slight dislocation without impingement or decrease of range of motion within the knee joint.