Response to ‘Letter to the editor regarding: In-brace alterations of pulmonary functions in adolescents wearing a brace for idiopathic scoliosis by Yagci et al.’

My co-authors and I thank the author(s) for their inquiry and remarks regarding our recent study reporting in-brace alterations of pulmonary functions in adolescents wearing a brace for idiopathic scoliosis. Your comments revealed several important points that need to be emphasized about the study.

First of all, we agree with you that evaluating the effects of bracing on pulmonary function is an important aim, but only if the appropriate orthosis is applied to children that require it. We propose that an appropriate orthosis was applied for each patient with idiopathic scoliosis included in our study.

As we reported in the article, the mean age of the participants was 14.5 ± 1.5 years. But contrary to what you have indicated in your letter, age was not one of the inclusion criteria. To put this in more detail, participants’ age was between 12 and 16 years old and skeletal maturity according to the Riser’s grade was 2 or 3. None of our participants had reached skeletal maturity (Risser 4 or above), and this is why they were treated with the bracing method. In addition, all participants were referred by an orthopaedic surgeon with a prescription for brace treatment due to their curve progression in follow-up.

In your letter, you reported that, according to Lonstein and Carlson, ¹ which is an old study published in 1984, 14.5 years of age usually complies with a Risser of 4 in Mediterranean girls. We argue that, in the 2020s, Turkish girls with idiopathic scoliosis tend to have a late menarche age and are likely to have curve progression during their growth period. Furthermore, for predicting scoliosis progression based on the classification of skeletal maturity for patients with idiopathic scoliosis, the Sanders method has been found to be more reliable and sensitive than Risser sign during peak growth velocity.^2,3 In addition, the Risser sign has been reported to have limited sensitivity, high mismatch risk and low intraobserver reliability. ² Unfortunately, we could not use Sanders’ classification due to the lack of hand-wrist radiographs of the patients, which may be one of the limitations of our study.

The issue about curve magnitudes has already been reported in the article, where we state that the main inclusion criteria was having moderate scoliosis: a Cobb angle of 20°–45° for the primary curve. Each participant had curve magnitude above 20°, which has been considered an indication for brace treatment in idiopathic scoliosis. ⁴ You can see the mean Cobb angle of the participants in Table 1.

Therefore, we disagree with your opinion that these children should not have been subjected to brace treatment. Our study participants had curve progression, appropriate curve magnitudes for bracing, and were within their skeletal growth period.

We agree with the authors that the aim of brace is to limit curve progression in idiopathic scoliosis. But this issue was not one of the hypotheses in our study, nor was the aim of the study to evaluate the effectiveness of brace treatment in idiopathic scoliosis. We kindly invite you to focus on the aims of the study, which were to determine the effects of bracing on pulmonary function in adolescents with idiopathic scoliosis, as stated in the article. As you recommend, we should have explained that the amount of in-brace correction was at least 40% for each patient, which has been reported in the literature as the standard for brace success. ⁴

We believe that we gave sufficient detail about brace design in the study. Comparison of the effects of two different types of braces such as a symmetric thoraco lumbo sacral orthosis (TLSO) and asymmetric Chêneau style brace was not a hypothesis of our study. We suggest that this should be investigated in future studies as it will make an important contribution to the literature.