Comparison of 2 Different Cast Configurations for Ponseti Cast: A Randomized Controlled Study.

Abstract

Different cast configurations are available in the literature for the application of the Ponseti cast. To dispel the ambiguity and generate better evidence, we tested 2 cast configurations (standard vs. reinforced) for their effectiveness in terms of retained ankle dorsiflexion and overall cast integrity. We randomized the 2 limbs of a child with bilateral idiopathic clubfeet (n=30 children) to receive a weight-matched standard cast (circular rolls only) or a reinforced cast (additional knee and plantar slabs). The post tenotomy cast was chosen as the index cast for the research purpose. Evaluations included clinical ankle dorsiflexion, immediate post tenotomy, and at the time of cast removal. Any cast breakages were also noted. The mean child's age was 3.5 months. The mean ankle dorsiflexion achieved immediately post tenotomy in either cast configuration was identical (15.5 degrees). At follow-up, 9 children presented with broken casts, 2 bilaterally. Overall, 9 standard (30%) and 2 reinforced (7%) casts were broken. For the broken casts, the ankle dorsiflexion was lost significantly. On intergroup comparisons, the reinforced casted limbs retained the ankle dorsiflexion significantly better (P=0.008) compared with the standard configuration. The reinforced cast configuration retained the ankle dorsiflexion much better than the standard cast. Frequent breakages were also noted with the standard cast.