Subtalar Arthrodesis and Dynamic Medial Column Stabilization in the Surgical Treatment of Rigid Progressive Collapsing Foot Deformity: A Comparative Analysis with Triple Arthrodesis

CATEGORY: Hindfoot; Midfoot/Forefoot INTRODUCTION/PURPOSE: In the surgical treatment of rigid progressive collapsing foot deformity (PCFD), triple arthrodesis has been commonly used for its ability to correct multiplanar deformities. However, complications associated with postoperative stiffness resulting from the added number of arthrodesis have led to an interest in more joint sparing options. A recent study has shown that dynamic medial column stabilization (DMCS), which transfers flexor hallucis longus tendon to the first metatarsal base, successfully restores medial longitudinal arch without the need for arthrodesis. This study aimed to evaluate the results of subtalar arthrodesis with dynamic medial column stabilization (DMCS) in treating rigid PCFD compared to the triple arthrodesis. METHODS: Sixteen patients (18 feet) who underwent triple arthrodesis (TA group) and 24 patients (24 feet) who underwent subtalar arthrodesis and DMCS (SA+DMCS group) for surgical correction of rigid PCFD were reviewed. Five radiographic parameters were measured preoperatively, 3 months, 6 months postoperatively, and at the last follow-up (minimum 2 years) to compare the amount of correction and its maintenance. Clinical outcomes were assessed using a visual analogue scale (VAS) and foot function index (FFI). Complications such as non-union, development of adjacent joint arthritis were recorded. RESULTS: TA group demonstrated a greater amount of correction in the Meary angle than the SA+DMCS group at 3 months postoperatively. However, the TA group showed a significant decrease in the medial cuneiform height, navicular-1st metatarsal angle, and Meary angle at 6 months compared to the initial reduction at 3 months. In contrast, the SA+DMCS group maintained initial correction throughout the follow-up (Figure 1). Clinical scores improved in all patients. Degenerative arthritis in the NC and TMT joints newly developed in nine and one foot, respectively, in the TA group. In contrast, there were no patients with newly developed arthritis in the SA+DMCS group. Postoperative valgus talar tilt occurred with nine ankles in the TA group, whereas only one ankle in the SA+DMCS group. One non-union of the subtalar arthrodesis occurred in the SA+DMCS group. CONCLUSION: SA+DMCS group demonstrated a comparable amount of correction as the TA group and maintained initial correction throughout the follow-up period. Additionally, the SA+DMCS group developed fewer complications than the TA group. The current findings suggest that SA+DMCS may be a viable option in treating rigid PCFD deformity with less concern for the complications related to the stiffness.