Objectives: To evaluate the efficacy of the Korat technique of serial casting both with and without early percutaneous needle Achilles tenotomy in clubfoot deformity correction, to analyze risk factors related to the recurrence of clubfoot deformity, and to evaluate the midterm clinical and radiographic results in identifying problems following treatment.

Materials and Methods: Clubfoot infants age up to 6 months who were initially treated at the Maharat Nakhon Ratchasima Hospital using the Korat technique between 2002 and 2013 were reviewed.
Infants with Dimeglio grade I, postural clubfoot, and those whose clubfoot had previously been treated were excluded. The number of cast changes to achieve normal foot form and the combined duration in cast were evaluated. Potential risk factors for recurrence were analyzed. The mid-term (3 to 13 years) clinical and radiographic outcomes were assessed.

Results: The study included 61 infants with 90 clubfeet, median age at first treatment 12 days (interquartile range 26). Early percutaneous Achilles tenotomy was done in 68 feet (76%). All feet
achieved normal foot form with a mean of 4.1+1.36 cast changes and a mean combined duration in cast of 4.2+1.30 weeks. Twenty-nine feet (32%) had a recurrence. A grade 0 initial peroneus muscle
function was associated with a 4.41-fold increase in clubfoot relapse (95% CI: 1.25, 15.49). At mid-term follow-up, all were pain free, plantigrade, and could walk and run. Twenty-five feet (28%) still had final peroneus muscle function less than grade IV which was related to the residual metatarsus adductus (odds ratio 4.93; 95% CI 1.23 to 19.74).

Conclusion: The Korat technique of manipulation and serial casting, either with or without early percutaneous needle Achilles tenotomy, is an alternative method for clubfoot deformity correction. Close regular follow-up is recommended for infants with grade 0 initial peroneus function and meticulous peroneus muscle strengthening exercises should be performed to decrease the risk of recurrence.

Keywords: Clubfoot treatment, Korat technique, serial casting, Achilles tenotomy, Peroneus muscle grading