A randomized clinical trial comparing reported and measured wear rates in clubfoot bracing using a novel pressure sensor

BACKGROUND:: The treatment of clubfoot by the Ponseti method requires the utilization of a foot abduction orthosis (FAO) after manipulation and casting. Adherence to this protocol, specifically FAO wear rates, has been postulated to improve treatment outcomes. Our hypothesis was that caregiver-reported wear rates were significantly less than actual wear rates in these braces. METHODS:: A randomized prospective study of 67 children, aged 0 to 3 years old with idiopathic clubfoot, treated using the Ponseti technique for idiopathic clubfoot, was undertaken after IRB approval. Participants were randomized into 3 groups: a functioning pressure-based sensor (group FPS) attached to the FAO (21 patients), a nonfunctioning sensor (NFPS group) attached to the FAO (24 patients), or no sensor (NS group) (22 patients). All caregivers filled out a diary of subjective wear rates. Reported and actual wear rates were recorded as a percentage of the entire day and compared. RESULTS:: In the FPS group, the average actual wear rate for months 1, 2, and 3 were 91.7% (15 patients; 72.7% to 97.0%), 86.8% (9 patients; 60.5% to 96.3%), and 77.1% (7 patients; 52.6% to 95.8%), respectively. The average self-reported wear rate in the FPS group in months 1, 2, and 3 were 94.9% (13 patients; 93.1% to 98.7%), 95.6% (10 patients; 92.3% to 99.4%), and 94.8% (11 patients; 82.8% to 99.6%), respectively. The most predictive factor in determining a patient's decrease in the overall wear rate was a drop in the wear rate between months 1 and 2 (P<0.001). The reported wear rates were not statistically different between any of the 3 groups (P<0.01). CONCLUSIONS:: By using a novel method of pressure measurement, which documented FAO wear, we have shown a significant decline in wear rates from months 1 to 3. These actual FAO wear rates did not match their reported rates, thus putting into question previous assumptions about reported brace compliance. The largest drop in wear rates occurred from months 2 to 3. This study provides the first objective measurement of FAO brace wear in patients undergoing the Ponseti method of treatment. LEVELS OF EVIDENCE:: Level II.