The relationship between patella position and length of the iliotibial band as assessed using Ober's test.

The purpose of the study was to investigate the relationship between length of the iliotibial band (ITB) and the medio-lateral position patella. Eighty subjects (37 male, 43 female) were examined for patella position and ITB length. All subjects were physically active, asymptomatic and aged between 18 and 34 years (mean 21.5 years). ITB length was assessed using the Ober's test and modified Ober's test, with hip adduction angle being measured using a fluid goniometer. Patella position was assessed using the method first described by McConnell [The management of chondromalacia patellae: a long term solution. Australian Journal of Physiotherapy 1986;32:215-22]. Patella position had a weak correlation (r=0.28) with modified Ober's (extended knee) test and a poor correlation with Ober's (knee flexed) test (r=0.1). In the group of 47 subjects with laterally displaced patellae, patella position had a moderate statistically significant correlation to ITB length measured by modified Ober's test (r=0.34, P=0.012). Only a poor relationship existed between Ober's test and patella position in the laterally displaced group. The results of this study only partially support the hypothesis that there is a relationship between ITB length and lateral patella displacement. The relationship was not strong enough to confirm ITB length as the only cause of lateral patella displacement.