Selective Talonavicular Arthrodesis With Talocalcaneal Stabilization for Flexible Planovalgus in Cerebral Palsy: Outcomes Within a Pathophysiology-Based Treatment Strategy.

BACKGROUND: Flexible planovalgus deformity in cerebral palsy (CP) is influenced by both structural alignment and dynamic muscle imbalance, affecting medial column stability. When tibialis posterior (TP) strength is markedly impaired, reconstructive osteotomies may fail to provide durable correction. This study evaluates the outcomes of selective talonavicular arthrodesis with systematic talocalcaneal stabilization (TNA-TCS) performed within a pathophysiology-based decision-making algorithm.

METHODS: All consecutive TNA-TCS procedures performed for flexible neurological planovalgus in ambulatory children with CP (GMFCS I to IV) were retrospectively reviewed. Surgical indication was based on deformity flexibility and TP strength (≤3/5 or unreliable assessment). Functional outcomes included the Functional Mobility Scale (FMS), Hoffer classification, walking distance, and pain and shoe-wear difficulties. Clinical outcomes were assessed using the Yoo score and patient satisfaction. Radiographic evaluation included standard angular parameters and sagittal "break" analysis. Complications and union rates were recorded. The mean follow-up was 4.5±1.6 years.

RESULTS: Forty-nine feet in 30 patients (mean age 12.8±2.6 y) were included. Walking distance improved significantly (P<0.001), with FMS improvement at 500 meters (P=0.01), while short-distance mobility remained stable. Functional gains were primarily observed in patients undergoing concomitant single-event multilevel surgery, whereas isolated TNA-TCS preserved ambulatory status. Pain and shoe-wear difficulties markedly decreased. Unsatisfactory clinical outcome (Yoo ≤8) occurred in 12% of feet. Overall satisfaction was high, with 83% of families reporting satisfaction or very satisfied. No talonavicular nonunion was observed. Hardware irritation requiring removal occurred in 2 patients.

CONCLUSIONS: Selective TNA-TCS was associated with satisfactory medial column stabilization and reliable fusion and functional preservation in ambulatory children with CP and TP weakness. In a flexible neuromuscular planovalgus with inadequate dynamic inversion strength, talonavicular arthrodesis with talocalcaneal stabilization represents a rational primary strategy within a pathophysiology-based algorithm.

LEVEL OF EVIDENCE: Level IV.