Nonoperatively Corrected Clubfoot at Age 2 Years: Radiographs Are Not Helpful in Predicting Future Relapse

Background: Nonoperative treatment of idiopathic clubfoot is standard. The purpose of this study was to determine if measurements made on standing lateral radiographs of successfully treated clubfeet made at 18 to 24 months of age were predictive of late recurrence. Methods: Inclusion criteria were idiopathic clubfoot with an age at presentation of ⩽3 months, nonoperative treatment resulting in a clinically plantigrade foot at 2 years of age, standing lateral radiograph of the involved foot made at 18 to 24 months of age, and a minimum age of 4 years at the time of follow-up. The radiographs were assessed for the talocalcaneal angle and the tibiocalcaneal angle, with measurements made by 2 trained practitioners. The average values of the 2 raters were used. The interobserver reliability was calculated using intraclass correlation coefficients (ICCs). A total of 211 patients with 312 clubfeet were evaluated. The average age at the time of follow-up was 8.0 years (range, 4.0 to 13.3 years). Results at the time of follow-up were rated as good (maintained plantigrade foot), fair (required limited surgery to maintain, or return to, a plantigrade position), or poor (required posteromedial release). Results: Over time, 75% of the feet had a good result, 19% had a fair result, and 6% had a poor result. With regard to radiographic assessment, the ICCs were 0.97 (talocalcaneal angle) and 0.98 (tibiocalcaneal angle), demonstrating excellent agreement between the raters. The mean talocalcaneal angle differed significantly between the feet with a good clinical outcome and those with a fair outcome (28° versus 24°; p < 0.02), but did not differ significantly between those with a good versus poor outcome (28° versus 26°), or a fair versus poor outcome (24° versus 26°). There were no significant differences in the mean tibiocalcaneal angle among the groups (86°, 90°, and 84°, respectively) (p = 0.17). Conclusions: Most clubfeet that were clinically plantigrade at 2 years of age remained so, while one-fourth subsequently required some surgery for late recurrence, primarily limited procedures. The tibiocalcaneal angle and talocalcaneal angle from standing lateral radiographs made at 18 to 24 months of age were not helpful in predicting future relapse. Level of Evidence: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.