Initial correction predicts the need for secondary achilles tendon procedures in patients with idiopathic clubfoot treated with ponseti casting

Background: The Ponseti method is the most common method to treat idiopathic clubfoot in North America. Despite initial correction, recurrence is common with this method. The factors predictive of recurrence are not well defined in the literature. Methods: A retrospective chart review was done of procedures performed at our institution from 2005 to 2010 in children undergoing general anesthesia for primary percutaneous Achilles tenotomy for the treatment of idiopathic clubfoot using the Ponseti casting method (101 patients, 148 feet). All patients were followed up for at least 2 years postoperatively (2 to 7.5 y, average 3.5 y). The patients were divided into 2 groups: group N with no repeat procedures on Achilles tendon and group R with a secondary procedure to address the residual equinus deformity. We looked at postoperative equinus correction through the use of postoperative measurements on digital images using a goniometer. The amount of postoperative dorsiflexion at the initial procedure was compared between the 2 groups using the paired t test. The feet were then divided into 3 groups on the basis of the amount of initial correction, and the rates of future surgical procedures were compared among these groups. Results: A total of 101 patients (148 feet) were evaluated. Seventy- two patients (106 feet) did not have any future procedures to address equinus deformity (group N). Twenty-nine patients (42 feet) underwent future procedure (group R) to correct the residual equinus. The N and R groups differed in amount of postoperative dorsiflexion (14.0 vs. 5.1; P<0.01). Patients in whom at least 10 degrees of dorsiflexion was achieved after the initial tenotomy had only a 12% rate of future procedures. Patients with neutral or less than neutral dorsiflexion had 64% chance of future procedures to address the residual equinus. Conclusions: Residual equinus deformity after Achilles tenotomy in clubfeet treated by the Ponseti method is associated with a high rate of future surgical procedures. Correction of this deformity before bracing could potentially decrease the rate of future surgery. Level of Evidence: Level III-Retrospective.