Can clinical assessment differentiate partial thickness rotator cuff tears from full thickness rotator cuff tears? A secondary analysis.

Shoulder pain causes significant disability, with rotator cuff disease as a common diagnosis. Differentially diagnosing partial tears of the rotator cuff tendons is difficult despite use of imaging and clinical examination. Our objective was to determine if a clinical assessment framework could discriminate between patients with partial and full thickness tears. Pre-operative baseline data from two randomized controlled trials of 452 adult patients awaiting rotator cuff repair were analyzed in this secondary analysis. Nineteen items from a pre-defined clinical assessment framework were investigated for association with the outcome of surgically confirmed partial or full thickness tear. Logistic regression tested independent associations and multivariable models were developed to create the most parsimonious model. Thirty-two participants (7%) had partial thickness tears. Constant Power Score was the sole item associated with partial thickness tears (OR 1.07, 95% CI 1.02-1.12). Traumatic mechanism of injury trended toward significance (OR 2.17, 95% CI 1.06-4.48). Greater abduction strength (i.e., Constant Power Score) was associated with partial thickness tears. Other clinical assessment items did not differentiate between partial and full tears. Our results add to the growing body of research showing most clinical findings are not associated with a diagnosis in rotator cuff disease.Implications for RehabilitationGreater shoulder abduction strength (as measured with the Constant Power Score) was associated with partial thickness rotator cuff tears.Most findings within our clinical assessment framework did not distinguish between partial thickness and full thickness rotator cuff tears and thus, did not contribute to a differential pathoanatomical diagnosis.Since structural integrity of the rotator cuff and patient presentation show poor association, and rehabilitation intervention is often impairment-based, pathoanatomical diagnosis may not adequately direct non-surgical treatment. Including movement-based diagnoses or treatment classification systems in evaluation of rotator cuff disease may improve selection of appropriate conservative treatment.