Predicting the need for tenotomy in the Ponseti method for correction of clubfeet.

The purpose of this study was to determine how to predict the need for tenotomy at the initiation of the Ponseti treatment. Fifty clubfeet (35 patients) were prospectively rated according to Pirani and Dimeglio scoring systems. Tenotomies were performed in 36 of 50 feet (72%). Those that underwent tenotomy required significantly more casts (P = 0.005). Of 27 feet with initial Pirani scores > or = 5.0, 85.2% required a tenotomy and 14.8% did not; 94.7% of the Dimeglio Grade IV feet required tenotomies. Following removal of the last cast, there was no significant difference between those that did and did not have a tenotomy. Children with clubfeet who have an initial score of > or = 5.0 by the Pirani system or are rated as Grade IV feet by the Dimeglio system are very likely to need a tenotomy. At the end of casting, feet were equally well corrected whether or not they needed a tenotomy.