Efficacy of external fixation in treating rigid equinus associated with fibro-adipose vascular anomaly

To evaluate the efficacy of external fixation in treating rigid equinus deformity associated with fibro-adipose vascular anomaly (FAVA).

This retrospective study included five patients (four males, one female; mean age 19.4 ± 5.6 years) with FAVA-related rigid equinus who underwent external fixation between January 2021 and August 2023. Three patients were treated with the Ilizarov apparatus and two with the Taylor Spatial Frame. Radiological outcome was measured by the anterior tibiotalar angle (TTA) on weight-bearing lateral radiographs. Functional assessments included the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, weight-bearing Visual Analog Scale (VAS) for pain, and patient satisfaction using a Likert scale.

The overall follow-up duration was 46.6 ± 13.2 months. The first assessment was performed at a mean of 20.6 ± 13.2 months and the second at a mean of 46.6 ± 13.2 months. At the first assessment, peak ankle dorsiflexion improved significantly from - 43.4 ± 10.4° preoperatively to 4 ± 6.5° (P < 0.05); TTA improved from 145.0 ± 18.3° to 106.8 ± 3.0° (P < 0.05); and AOFAS score increased from 63.6 ± 4.6 to 75.8 ± 8.0 (P < 0.05). Weight-bearing VAS changed from 2 ± 1.2 to 0.8 ± 0.8 (P > 0.05). At the second follow-up, AOFAS score was 77.2 ± 12.1 (P < 0.05 vs. preoperative) and VAS was 1.4 ± 0.5 (P > 0.05 vs. preoperative). The patient satisfaction rate was 80%. Two patients experienced mild recurrence and one patient had severe recurrence.

Gradual correction of rigid equinus deformity secondary to FAVA using external fixation is safe and yields satisfactory short- to mid-term outcomes, providing valuable evidence for the management of this rare condition.