AN ANALYSIS OF DIFFERENT FORMS OF SURGICAL FIXATION FOR AVULSION FRACTURES OF ANTERIOR TIBIAL SPINE

Abstract

Introduction: Avulsion fractures of the anterior tibial spine are not so common. The best form of treatment for displaced fractures is still debatable.

Aims: We aimed to analyze the results of different forms of internal fixation for avulsion fractures of the anterior tibial spine.

Material and Methods: Twenty-five patients with avulsion fractures of the anterior tibial spine had open reduction and internal fixation with different implants (AO screw, Herbert screw, stainless steel wire loop and absorbable stitch) and techniques. The mean follow up period was 3.66 years. They were evaluated clinically and radiologically, using KT 1000 arthrometer for ACL laxity and goniometer for range of movements. The outcome was measured using Lysholm Knee Score.

Results: Significant residual anterior laxity despite adequate fracture union was a common finding. Maximum ACL laxity was seen in adults in whom absorbable stitches had been used and they had a corresponding lower Lysholm score. Significant migration of the Herbert screws was noted in two of five patients in which it was used. Five of the eight patients with higher Lysholm score had AO screw fixation. Three patients with steel wire loop for stabilization of the fracture also had better results comparatively. Three individuals who had their knee immobilised in 25°–50° of flexion developed fixed flexion deformities, which took 12–18 months to recover.

Conclusions: The use of absorbable stitches as the primary method of fixation for avulsion fractures of the tibial spine should be avoided in adults. Herbert screw in this situation has a tendency to migrate. AO screws and non-absorbable loop yields better functional outcome. Immobilization of the knee in excessive flexion leads to prolonged fixed flexion deformity. Early range of movements can be achieved by replacing cast with a brace allowing flexion up to 90 degrees.