Bone density of the greater tuberosity is decreased in rotator cuff disease with and without full-thickness tears.

BACKGROUND Despite the high prevalence of rotator cuff disease in the aging adult population, the basic mechanisms initiating the disease are not known. It is known that changes occur at both the bone and tendon after rotator cuff tears. However, no study has focused on early or "pretear" rotator cuff disease states. The purpose of this study was to compare the bone mineral density of the greater tuberosity in normal subjects with that in subjects with impingement syndrome and full-thickness rotator cuff tears. MATERIALS AND METHODS Digital anteroposterior shoulder radiographs were obtained for 3 sex- and age-matched study groups (men, 40-70 years old): normal asymptomatic shoulders (control), rotator cuff disease without full-thickness tears (impingement), and full-thickness rotator cuff tears (n = 39 per group). By use of imaging software, bone mineral densities were determined for the greater tuberosity, the greater tuberosity cortex, the greater tuberosity subcortex, and the cancellous region of the humeral head. RESULTS The bone mineral density of the greater tuberosity was significantly higher for the normal control subjects compared with subjects with impingement or rotator cuff tears. No differences were found between the two groups of patients with known rotator cuff disease. The greater tuberosity cortex and greater tuberosity subcortex outcome measures were similar. CONCLUSION Bone mineral changes are present in the greater tuberosity of shoulders with rotator cuff disease both with and without full-thickness tears. The finding of focal diminished bone mineral density of the greater tuberosity in the absence of rotator cuff tears warrants further investigation.