Abstract
Statement of purpose:
A randomised clinical trial was undertaken to find out if treatment time and failure rate in children treated by the Ponseti method differed between below-knee vs above-knee cast groups.
Methods and Results:
Eligible children with idiopathic clubfoot, treated using the Ponseti method, were randomised to either below knee or above knee plaster of Paris casting. Outcome measures were total treatment time and the occurrence of failure, defined as two slippages or a treatment time above eight weeks. Twenty-six children (33 feet) were entered into the trial, with a mean age of 17 days (range 1–40) in the above knee and 11 days (range 5–20) in the below knee group. Because of six failures in the below knee group (38%), the trial was stopped early for ethical reasons. Failure rate was significantly higher in the below-knee group (P 0.039). The median treatment times of six weeks in the below knee and four weeks in the above knee group differed significantly (P 0.01).
Statement of conclusion:
Below knee plaster of Paris casts in conjunction with the Ponseti method showed significantly higher rates of failure than above knee plaster casts, requiring conversion to above knee casts, and a significantly longer treatment time. This higher rate of failure of below knee casts forced an early end of the trial. This study shows that a well moulded above knee plaster cast is safe and superior to a below knee plaster cast in conjunction with the Ponseti method. We do not believe that modifying the original Ponseti method in this manner is beneficial.
Level of evidence: I
