Sonia Sahli, PhD

The Spine Journal
Available online 2 October 2013

Abstract
Background context
Concerns have been raised about the effect of backpack carrying on adolescent balance. For adolescent idiopathic scoliosis (AIS) subjects, the effect of backpack carrying method on their balance has not been determined. Our aim is to examine the effects of backpack load and carrying method on AIS subjects’ balance.

Study design/setting
Paired sample matched for age and sex.

Patient sample
Twelve healthy adolescents matched for age and sex with 14 adolescents with mild AIS participated in this study.

Outcome measures
A test battery including clinical examination, radiological assessment, and stabilometric measurements of the postural sways in the upright standing posture were conducted.

Methods
Center of pressure excursions of our subjects were recorded with a stabilometric platform during the upright standing posture without a backpack and while carrying a backpack symmetrically and asymmetrically on each shoulder. For each carrying method, the backpack is loaded at 10% and 15% of body weight (BW).

Results
Our results indicated that postural sways increased with increasing backpack load. These postural sways were observed when normal adolescents carried a backpack loaded with 15% BW load, whereas, for age- and sex-matched AIS subjects, these postural responses were observed for the 10% BW load. The symmetrical backpack carrying induced better balance compared with the asymmetrical one. Asymmetrical carrying on the convex side of the scoliotic curve affects AIS subjects’ balance more than carrying it on the concave side.

Conclusions
Load carriage of 10% BW seems to alter AIS subjects’ balance. Asymmetrical carrying should be avoided especially on the convex side of the scoliotic curve because it causes balance impairments that may increase spinal pain.

Abstract Online:  http://www.sciencedirect.com/science/article/pii/S1529943013006980