Abstract
The purpose of this study was to test the null hypothesis that patients with partial thickness rotator cuff tears do not suffer more pain or stiffness than those with full thickness tears. A power study determined that 68 partial thickness tears were required in the study in order to prove a clinically important difference (± = 0.05 and 2 = 0.2). Consecutive patients undergoing arthroscopy and bursoscopy for rotator cuff related problems were assessed using a pain analogue scale and their shoulder movements were measured. Information was gained both pre- and intra-operatively about possibly relevant confounders including age, site size and thickness of tears, and endocrine disorders. Exclusion criteria included glenohumeral arthropathy, frozen shoulder, instability and major traumatic injuries, as well as the inability to understand the pain score. 439 shoulders (428 patients) were included in the study; 216 shoulders had no cuff tear, 95 had partial thickness tears (75 joint side, 1 intrasubstance, 19 bursal side), and 128 shoulders had full thickness tears. There was no significant difference (p< 0.05) in the pain scores or range of movement between full and partial thickness tears. Age was the only independent variable to have an effect on pain score.
The null hypothesis has been upheld. This study contradicts the findings of previous research and challenges commonly held assertions on this topic. Neither pain nor stiffness can be used clinically as discriminators between partial and full thickness rotator cuff tears.
Correspondence should be addressed to The Secretary, British Elbow and Shoulder Society, The Royal College of Surgeons of England, 35–43 Lincoln’s Inn Fields, London WC2A 3PE.