Open Reduction and Internal Fixation of Isolated Posterior Cruciate Ligament Avulsion Fractures: Clinical and Functional Outcome

PURPOSE: The posterior cruciate ligament (PCL) presents commonly with avulsion fractures of its tibial attachment. An avulsion fracture of the PCL, if not surgically fixed, may lead to secondary changes in the knee joint. Various fixation techniques have been explored with use of lag screws, steel wires, absorbable screws, suture anchors and straddle nails. The purpose of this study was to evaluate the clinical and functional outcome of open reduction and internal fixation of tibial avulsion injuries of the PCL using cannulated cancellous screws. MATERIALS AND METHODS: We performed open reduction and internal fixation using cannulated cancellous screws in 14 patients (mean age, 33.9 years) with isolated PCL avulsion injuries. Patients with a duration of injury more than 12 weeks were excluded. The minimum follow-up period was 12 months. Results were assessed radiologically and clinically. Final functional outcome was assessed using the Lysholm knee scoring system. RESULTS: The average follow-up period was 13.5 months. At the final follow-up, all 14 patients achieved fracture union. The average flexion was 121.7°±9.2° with full extension achieved in all patients. Mild instability (1+) was noted in 4 patients. The Lysholm functional score was excellent in 11 patients, good in 2 patients and fair in 1 patient with an average score of 97±7.6. CONCLUSIONS: Stable early fixation for PCL avulsion injuries with early controlled mobilization provided excellent to good results. However, fixation should not be discouraged for late-presenting patients because good to fair results can be achieved in such cases.