The Objective Measurement of Brace-Use Adherence in the Treatment of Idiopathic Clubfoot.

BACKGROUND

A successful outcome for the treatment of idiopathic clubfoot is believed to require adequate adherence to brace use. Previous studies have relied on parental reporting of brace application. We used temperature sensors to determine the adherence to the bracing protocol, the accuracy of parent-reported use, and differences in adherence between patients who experienced relapse of deformity and those who did not.

METHODS

Using wireless sensors attached to brace sandals, we monitored brace wear over a 3-month period in this cross-sectional study involving 48 patients in 4 age-based groups: 6 to 12 months (Group 1), >1 to 2 years (Group 2), >2 to 3 years (Group 3), and >3 to 4 years (Group 4). Parents were blinded to the purpose of the sensors. The mean number of hours of daily brace use as measured by the sensors was compared with the physician-recommended hours and parent-reported hours of brace use.

RESULTS

Sensors were retrieved from 44 of 48 patients. Overall, the median brace use recorded by the sensors was 62% (range, 5% to 125%) of that recommended by the physician, and 77% (range, 6% to 213%) of that reported by the parents. For Groups 1 to 3, the difference between the physician-recommended and measured number of hours of daily brace use was significant (p ≤ 0.002), and the difference between the parent-reported and measured number of hours of daily brace use was also significant (p ≤ 0.013). Eight (18%) of the 44 patients who completed the study experienced relapse during the period of monitoring; most importantly, the mean number of hours of brace wear for these patients, 5 hours per day (median, 4; and standard deviation [SD], 3 hours per day) was significantly lower than the 8 hours per day for those who did not experience relapse (median, 9; and SD, 5 hours per day) (p = 0.045).

CONCLUSIONS

The present study objectively quantified the number of daily hours of post-corrective brace wear for patients with clubfoot in varying age groups and provides an estimate of the number of hours required to avoid relapse.

LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.