It is reported that adolescent idiopathic scoliosis patients have abnormal bone quality. However, the study of bone quality in idiopathic scoliosis (IS) patients is still sparse. The objective of this study was to determine whether an association exists between IS and bone quality in a school scoliosis screening program.

In total, 391 IS patients (263 girls/128 boys) and 282 healthy controls (185 girls/97 boys) from 6 to 19 years of age in a school scoliosis screening program were included. Quantitative ultrasound measurements were performed at the left distal 1/3 of the radius, and the standard method to estimate speed of sound was recorded. Z-score was then calculated. The Z-score is defined as the difference between the raw score to be standardized and the mean difference divided by the standard deviation (a Z-score less than or equal to −2.0 indicates low bone quality and a Z-score greater than −2 indicates normal bone quality).

The mean age of IS patients and healthy controls were (12.1±3.2) and (10.7±3.0) years old respectively. The mean Cobb angle of IS patients was 14.7°±4.9°. Of 391 IS patients, 101 (25.8%) had low bone quality. Of 282 healthy controls, 51 (18.1%) had low bone quality. There was significant association between IS and low bone quality (OR: 1.58; 95% CI: 1.08–2.30). After adjustment for age, gender and body mass index, a positive association was seen between IS and low bone quality (OR: 1.60; 95% CI: 1.08–2.37).

IS patients have a higher risk of low bone quality. It is recommended that bone quality should be monitored in IS patients.