Oxford shoulder score in a normal population

BACKGROUND: The function of the asymptomatic normal shoulder may differ according to gender and could also deteriorate with age. This may result in a disparity in the normal Oxford shoulder score (OSS) according to these variables. If a difference were to exist an adjusted OSS, for age and gender, could be calculated from the raw score using the expected normal score. AIM: The aim of this study was to define a normal OSS in an asymptomatic population according to age and gender. MATERIALS AND METHODS: During the study period 202 patients aged from 20 years to 99 years with subjectively asymptomatic shoulders completed an OSS. These patients presented to the study center during a 1 week period for management of disorders out with their shoulder girdle. Patients with a known prior shoulder pathology, injury, or polyarthropathy were excluded. RESULTS: The mean OSS varied according age and gender. There was a significant correlation between age and the OSS, with an increasing score (worse) being associated with older age (r = 0.62, P < 0.0001). The mean OSS for females was 18.8 (12-42, SD 5.4) and for males was 16.3 (12-30, SD 4.5), this difference was significant (P = 0.0001). We propose that a normalized OSS could be calculated as a percentage by the using the expected normal for that patient's age and gender as demonstrated in this study ((raw score/normal score) × 100). CONCLUSION: Our study provides normal data for an urban population presenting to orthopedic services and allows for a relative OSS to be calculated from the raw score.