Time in brace: where are the limits and how can we improve compliance and reduce negative psychosocial impact in patients with scoliosis? A retrospective analysis

Background: Brace treatment for adolescent idiopathic scoliosis (AIS) is generally prescribed for 18-23 hours per day, but the minimal time of brace wear per day to stop progression of AIS is still unclear. Compliance of patients with AIS with brace treatment is reported to be between 27% and 47% of the prescribed time, brace wear especially at school is often described as embarrassing by adolescent patients. It has been reported that a higher rate of compliance leads to a significantly lower rate of curve progression. Theoretically, prescribing brace treatment 16 hours instead of 23 hours per day (patients are allowed to attend school free of their brace) could lead to a higher rate of compliance, and subsequently reduce progression rate of patients with AIS.

Purpose: To investigate if brace treatment 16 hours per day is noninferior to >16 hours with regard to curve progression, and if other clinical and demographic factors that might influence incidence and progression (apart from time of brace wear) of AIS can be identified.

Study design: In a retrospective study, we investigated patients with AIS who had been admitted to our outpatient clinic and enrolled them in one of three groups: group 1 brace <12 hours per day, group 2 brace 12-16 hours per day, and group 3 brace >16 hours per day.

Patient sample: Seventy-two patients met our inclusion criteria and were enrolled in our study, 61 female and 11 male patients. Twenty-eight were allocated in group 1, 13 in group 2, and 25 in group 3.

Outcome measures: Progression of Cobb angle with regard to brace wear per day was the main outcome measure.

Methods: Skeletally immature patients who presented from October 2010 to June 2013 with an AIS and a Cobb angle >20° were enrolled in our study and have been prescribed a Chêneau orthesis. Demographic parameters, progression of Cobb angle, and time of brace wear have been recorded. Groups 1, 2, and 3 of brace wear were analyzed for differences.

Results: The overall difference between the groups referring to increase of Cobb angle was significant (p<.05). Further analysis of groups 2 and 3 showed that the difference between these groups was not significant (p>.05). Apart from time of brace wear, no other factor showed any influence on curve progression. Smoking status of parents of our patients was significantly more often positive than in the general local population (p>.05).

Conclusions: Twelve to 16 hours of brace wear per day did not lead to a higher progression rate of AIS compared with more than 16 hours in our study group. Our analysis showed that smoking status of parents possibly contributes to the risk of developing AIS; however, we did not find an impact on progression of scoliosis.