Radiographic Indicators of Surgery and Functional Outcome in Ponseti-Treated Clubfeet.

BACKGROUND

Evaluation of the results of treatment for clubfoot by the Ponseti technique is based on clinical and functional parameters. There is a need to establish universally recognized quantitative measurements to compare, better understand, and more precisely evaluate therapeutic outcome.

METHODS

Nine angles were measured on standard radiographs of 145 children with idiopathic clubfeet treated between 2000 and 2010 with the Ponseti method. The average follow-up was 6.3 years. The need for additional surgery and the functional outcome was correlated to the radiologic measurements.

RESULTS

Three radiologic parameters were identified as having significant (P ≤ .001) predictive value. The lateral tibiocalcaneal angle with the ankle at maximal dorsiflexion measuring fixed equinus was larger in the preoperated group (77 ± 12 degrees) compared to the nonoperated group (67 ± 14 degrees). Functional outcome was better with smaller angles. The lateral talocalcaneal angle with the ankle at maximal dorsiflexion measuring hindfoot rigidity was smaller (29 ± 8 degrees) in the preoperated group compared to the nonoperated group (35 ± 9 degrees). Functional outcome was better with larger angles. The lateral talo-first metatarsal angle with the ankle at maximal plantarflexion measuring foot cavus was larger in the preoperated group (31 ± 10 degrees) compared to the nonoperated group (22 ± 11 degrees), whereas functional outcome did not correlate with this angle.

CONCLUSIONS

The lateral view with the foot in maximal dorsiflexion was found to be the most significant and useful view to detect abnormality in Ponseti-treated clubfeet. In our practice now, we are using only this view in order to reduce the radiation exposure to the child.

LEVEL OF EVIDENCE

Level III, retrospective case series.