Long-term results of surgical reconstruction for chronic lateral instability of the ankle: comparison of Watson-Jones and Evans techniques.

Evans and Watson-Jones described different techniques for reconstructing the lateral ligament of the ankle in patients with chronic lateral instability, but long-term results of the two techniques are not clear. This retrospective study compares the results in 20 adults at an average followup of 5 years (range 4 to 8). Preoperatively all patients showed an average talar tilt of 15 degrees more than the normal side. Ten patients had the Evans procedure and ten the Watson-Jones operation. Nineteen patients had good or excellent clinical results with a stable ankle. Radiographic studies showed minimal residual instability which was more marked in plantar flexion than in neutral, but this did not jeopardize the end results. Long-term clinical results of the two operations are similar. However, the Evans technique controlled talar tilt better whereas the Watson-Jones operation was more effective in reducing anteroposterior instability.