Ultrasound imaging for the rheumatologist XLIV. Ultrasound of the shoulder in healthy individuals.

OBJECTIVES To investigate the prevalence of shoulder ultrasound (US) detectable abnormalities in asymptomatic individuals of various ages and to correlate the US findings with clinical data. METHODS 97 healthy subjects were enrolled in the present study. They were subgrouped according to their age, as follows: group I (20-29 years); group II (30-39 years); group III (40-49 years); group IV (50-59 years); group V (>60 years). A physical examination of both shoulders, based on a series of provocative maneuvers, was carried out. The US assessment was performed by using a Logiq9 machine equipped with a multi-frequency linear probe working at 12MHz and included the study of a number of structures for the evaluation of local abnormalities, as follows: the long head of biceps tendon (synovial effusion (SE), synovial hypertrophy (SH), power Doppler (PD) signal); the subacromion-subdeltoid and sub-scapularis bursae (SE, SH, PD signal); the rotator cuff tendons (tendinosis, calcifications, tears, impingement); the acromionclavicular (ACJ) and gleno-humeral joints (SE, SH, PD signal, osteophytes, erosions, fibrocartilage calcifications, cartilage abnormalities, tophaceous deposits). In addition, deltoid, throchite and throchine enthesopathy were searched for. RESULTS 194 shoulders were studied in total. A low but variable percentage of joints of healthy individuals (3.1-13.4%) showed positive provocative maneuvers. 138 shoulders (71.1%) did not show any US abnormalities. The most frequent changes were SE of ACJ (25.5%), osteophytes of ACJ (23.3%), and supraspinatus tendinosis (20.6%). The prevalence of abnormalities progressively increased with age. Sub-clinical involvement was present in most cases, being provocative maneuvers positive only in a low percentage of joints. CONCLUSIONS The present study demonstrated the presence of a wide set of US-detectable changes in healthy subjects, that were more frequently present in elderly individuals. The absence of any clinical sign of local pathology cannot exclude the presence of local abnormalities.