Pes planovalgus is the most common foot deformity in children with cerebral palsy (CP). Many of these patients become functionally limited and require surgical intervention. The objectives of this study are to apply previously validated radiographic parameters to radiographs of children with CP who have undergone surgical intervention for pes planovalgus deformity and to assess if these radiographic parameters show improvements post-operatively. Furthermore, this study aims to determine which of these parameters can most accurately be used to quantify correction post-surgery.
A retrospective review was performed to identify patients aged five to 17 with a diagnosis of CP who underwent lateral calcaneal lengthening osteotomy for pes planovalgus between 2006 and 2015 at London Health Sciences Center. The previously validated radiographic measurements were applied to pre-operative and post-operative radiographs. A normality test was performed to observe whether participants were normally distributed with regard to the severity of their deformity. Paired T-test and Wilcoxon signed-rank test were used to compare changes in radiographic measurements from before and after surgery.
Seventeen patients met the inclusion criteria. The average age of selected patients was 13.06 years (range 9.42-16.75 years). This included 11 males and six females, all with spastic CP (12 diplegic, five hemiplegic). Of these patients, 11 underwent bilateral surgery and six underwent unilateral surgery (28 feet). These patients were followed post-operatively for a mean of 7.97 months (range 1.5-20 months). In comparing the radiographs from before and after surgery, statistically significant changes were seen in five out of the seven measurements. Talonavicular coverage angle was found to have the most significant change post-correction.
The previously validated radiographic parameters used to assess foot and ankle deformity can be applied to the surgically treated pes planovalgus foot in patients with CP. It was found that five out of the seven measurements used to assess foot deformity changed significantly with surgical intervention. Talonavicular coverage angle was found to be the most accurate measure for post-surgical correction. This is the first study to apply these parameters to CP patients with surgically treated flatfoot deformity. Lateral calcaneal lengthening osteotomy significantly improves these radiographic measures.