A validation of the Nottingham Clavicle Score: a clavicle, acromioclavicular joint and sternoclavicular joint–specific patient-reported outcome measure

Abstract

Patients with acromioclavicular joint (ACJ) and sternoclavicular joint (SCJ) injuries and with clavicle fractures are typically younger and more active than those with other shoulder pathologies. We developed the Nottingham Clavicle Score (NCS) specifically for this group of patients to improve sensitivity for assessing the outcomes of treatment of these conditions compared with the more commonly used Constant Score (CS) and Oxford Shoulder Score (OSS). This was a cohort study in which the preoperative and 6-month postoperative NCS evaluations of outcome in 90 patients were compared with the CS, OSS, Imatani Score (IS), and the EQ-5D scores. Reliability was assessed using the Cronbach α. Reproducibility of the NCS was assessed using the test/retest method. Effect sizes were calculated for each score to assess sensitivity to change. Validity was examined by correlations between the NCS and the CS, OSS, IS, and EQ-5D scores obtained preoperatively and postoperatively. Significant correlations were demonstrated preoperatively with the OSS (P = .025) and all subcategories of the EQ-5D (P < .05) and postoperatively with the OSS (P < .001), CS (P = .008), IS (P < .001), and all subcategories of EQ-5D (P < .02). The NCS had the largest effect size (1.92) of the compared scores. Internal consistency was excellent (Cronbach α = 0.87). The NCS has been proven to be a valid, reliable and sensitive outcome measure that accurately measures the level of function and disability in the ACJ, SCJ and clavicle after traumatic injury and in degenerative disease.