My aching shoulder

Diagnostic Challenge

CJEM 2007;9(4):296

Case history

A previously healthy 43-year-old man was referred to the emergency department (ED) from a sports medicine clinic because of persistent shoulder pain and reduced function. He first presented to the clinic about 1 week earlier with pain and decreased range of motion in his right shoulder. The pain was described as a constant, background dull ache with superimposed stabbing pain when he moved his arm. Intermittently, he experienced parasthesias in the distribution of the ulnar nerve along with chills and sweats, but no documented fever. Because his symptoms began after lifting heavy boxes, the referring physician originally diagnosed his condition as a shoulder strain.

Physical examination in the ED revealed a well-appearing man, who was in no distress. His vital signs were stable and he was afebrile. There was no cutaneous erythema, induration or increased warmth overlying the shoulder, however, slight edema to the pectoral and shoulder region was present. No axillary, supraclavicular or cervical lymphadenopathy was detected. The brachial and radial pulses in the right arm were normal. Abduction and extension of the right arm was limited by pain. There was no bony tenderness or crepitus along the distal clavicle, acromioclavicular joint, shoulder or upper arm. The muscle bulk was symmetric. Sensation in the terminal nerve distributions was grossly normal. Motor function about the elbow, wrist and hand was normal. Auscultation of the chest revealed crackles in the right lower lung field, posteriorly. The remainder of the physical examination was normal.

Question

The next step in the investigation of this man's shoulder pain would be to order:

1. a complete blood count (CBC);
2. a chest x-ray;
3. an erythrocyte sedimentation rate (ESR);
4. magnetic resonance imaging (MRI) of the shoulder.

See the Answer to this Challenge.