Garceau Technique Requires Less Mechanical Work Than Modified Ponseti for Tibialis Anterior Tendon Transfer: A Biomechanical Study in Cadavers.

BACKGROUND

Tibialis anterior tendon transfer is used to correct dynamic supination in patients with relapsed clubfoot. While both the Garceau and modified Ponseti techniques are clinically accepted, they differ in tendon routing: The Garceau approach follows a straighter path without additional pulley formation, whereas the modified Ponseti technique may create a secondary distal pulley that increases the force required for dorsiflexion, which could have clinical implications for patient selection.

QUESTIONS/PURPOSES: Does the Garceau technique (1) require less force, (2) result in reduced tendon displacement, or (3) decrease the mechanical work needed to dorsiflex the foot, and if so, are differences in the resulting force-displacement curves reflected in earlier force onset, lower peak force at maximum dorsiflexion, and shorter tendon displacement to reach that end point compared with the modified Ponseti technique?

METHODS

Ten cryopreserved lower limbs from 10 unique donors (6 females, 4 males; mean ± SD age 82 ± 8 years) underwent simulated tibialis anterior contraction using a linear traction device. Limbs with no visible surgical scars, hardware, deformity, or arthrodesis of the tibiotalar, subtalar, or midtarsal joints were included; specimens showing any of these features or cutaneous defects were excluded. Each specimen was evaluated in a repeated-measure design under three sequential conditions: control (native tendon insertion, prior to surgical manipulation), after modified Ponseti technique, and finally after converting the modified Ponseti technique to a Garceau transfer. To simulate tibialis anterior muscle contraction, we used a Mecmesin MultiTest 2.5-d traction system (Slinfold). Peak force, tendon displacement, and mechanical work to achieve maximum dorsiflexion (defined for each specimen as the greatest dorsiflexion attainable under linear traction before additional load produced no further change) were recorded with Grafilino Max v 1.24 software (DataMicra). Repeated-measures ANOVA with post hoc testing was used.

RESULTS

The Garceau technique required lower peak force than the modified Ponseti technique to achieve maximal dorsiflexion (mean ± SD modified Ponseti 37 ± 5 N versus Garceau 27 ± 4 N, mean difference 10 [95% confidence interval (CI) 4 to 16]; p = 0.009). The Garceau technique also produced smaller tendon displacement than the modified Ponseti technique (modified Ponseti 33 ± 3 mm versus Garceau 26 ± 3 mm, mean difference 7 [95% CI 4 to 10]; p < 0.001). Consequently, the mechanical work needed to achieve maximum dorsiflexion was lower with the Garceau technique (modified Ponseti 443 ± 76 J versus Garceau 269 ± 47 J, mean difference 174 [95% CI 84 to 264]; p = 0.005), a reduction qualitatively reflected in earlier force application and shorter excursions on the force-displacement curve.

CONCLUSION

The Garceau technique requires less mechanical work than the modified Ponseti method to reach maximum dorsiflexion of the foot, likely because the tendon follows a more direct path, creating no additional tendon-reflection pulley.

CLINICAL RELEVANCE: For patients with limited muscular strength, the Garceau technique may lower energy demand during gait, supporting its consideration in surgical management of recurrent clubfoot. Comparative clinical gait-analysis studies that quantify postoperative dorsiflexion strength, gait kinetics, and relapse rates after each transfer technique are needed to determine whether this biomechanical advantage translates into improved clinical and functional outcomes.