Purpose The Ponseti method has become the gold standard for clubfoot treatment. Although promising short-term results have been published, only a few studies report results at the end of the bracing period. We aimed to evaluate the functional midterm results, rate of recurrence and need for subsequent surgery. Methods Patients from our prospective database of clubfeet treated with the Ponseti method with a minimum age of three years were identified. Exclusion criteria were syndrome or neurogenic association, address in a foreign country, presentation after six weeks of age, more than three casts applied elsewhere and correction with less than three casts. A total of 125 patients met the inclusion criteria. The Pediatric Outcomes Data Collection Instrument (PODCI), the disease-specific instrument (DSI) questionnaire and an invitation for a clinical examination were sent out. For patients not presenting for evaluation, data from the last follow-up were extracted. Results Seventy questionnaires (56 %) of patients with a mean age of 5.7 years (3.3-8.9 years) were returned. The DSI score (n=65) was 85.3 (± 13.01 SD) and the PODCI score (n=59) was 95.5 (± 6.3 SD). A total of 113 of 125 patients (90.4 %) with 182 clubfeet were examined in the study or seen in follow-up. During a mean follow-up of 5.2 years (range 3-8.5 years) a repeat tenotomy was performed in 4 % of cases, a percutaneous Achilles tendon lengthening in 3 %, a tibialis anterior tendon transfer in 13 % and open joint surgery in 5 %. The mean dorsiflexion with knee extended was 15.9°(range 0-32°; SD ±5.5) with 16 feet (9 %) presenting less than 10°. Conclusions The functional scores indicate that the Ponseti method results in mostly pain-free feet not limiting ageappropriate activity. In this consecutive case series open joint surgery could be avoided in 95 % of cases with a good functional and anatomic outcome.

Interobserver reliability with regard to the radiographic measurement of pediatric feet was higher than expected, although measurement discrepancies can be as great as 30° with the infant foot. Interobserver reliability tended to improve with increasing patient age. The standard deviation showed a trend toward a decrease as patient age increased, although the trend was less notable than expected.