Abstract
Left-right skeletal length asymmetries in upper limbs related to curve side have been detected with adolescent thoracic idiopathic scoliosis (AIS). In school screening referrals with thoracic scoliosis we find apical vertebral rotation (AVR, Perdriolle) is associated significantly with upper arm length asymmetry. Sixty-nine of 218 consecutive adolescent patients referred routinely during 1988–1999 had idiopathic thoracic scoliosis of whom 61 had left and right upper arm lengths measured with a Holtain anthropometer (right curves 49, left curves 12, mean age 14.9 years, girls 38 postmenarcheal 34, boys 23). The controls are 278 normal girls and 281 boys (11–18 years, mean age 13.5 years). The mean value for Cobb angle is 18 degrees (range 4–42 degrees), AVR 13 (range 0–34 degrees), Cobb angle (CA) and AVR are each positively associated with upper arm length asymmetry (p=0.001 & p< 0.0001 respectively) and after correcting for each of Cobb side, apical level, sex and handedness, AVR and upper arm length asymmetry are still significantly associated (p=0.004 ANOVA). Partial correlation analysis shows AVR is associated with upper arm length asymmetry after controlling for CA (p=0.033); but not CA and upper arm length asymmetry after controlling for AVR (p=0.595). The reason why a larger AVR to the right is associated with a relatively longer right upper arm is unknown. Possibilities include neuromuscular and skeletal mechanisms, the latter relative concave overgrowth of neurocentral synchondrosis and/or of periapical ribs. We suggest consideration be given to combining convex vertebral body stapling (Betz) with concave periapical rib resection (Sevastik and Xiong) for right thoracic AIS in girls.
Correspondence should be addressed to: Dr Caroline Goldberg, The Research Centre, Our Lady’s Children’s Hospital Crumlin, Dublin 12, Ireland.
