Correction of equinus deformity by means of a new unconstrained ilizarov frame system.

Purpose: This study aimed to clarify the effectiveness of a novel technique utilizing the new unconstrained Ilizarov frame system by evaluating the clinical outcomes of equinus deformity correction.

Methods: From January 1998 to December 2012, a total of 9 consecutive patients (median age: 33 years) with equinus deformity were treated by using a simple, unconstrained, hinge-less Ilizarov frame, which was developed to correct talar subluxation using an unconstrained frame system. All patients had equinus deformity >30°, although preoperative radiographs showed a congruous ankle joint with no fixed bony deformity. Preoperative equinus deformity was evaluated as well as dorsal flexion (DF) in Ilizarov at 3 months after removal and at final follow-up. Furthermore, the presence or absence of talar subluxation at the time removal of the Ilizarov apparatus, and whether or not ankle arthrodesis was finally indicated, was evaluated.

Results: Median follow-up period was 76 months. Median preoperative equinus deformity was -40° None of the patients showed anterior or posterior subluxation of the talus at the time of removal. Three months after removal of the Ilizarov apparatus, the median DF angle was -5° However, 4 patients showed less than -15° of DF and underwent ankle arthrodesis with the ankle joint in the 5° DF position. At the final follow-up, median DF angle was 5°.

Conclusion: This technique allows for safe, gradual correction of equinus deformity without talar subluxation, although additional procedures, such as ankle arthrodesis, may be needed in some cases.