Author: Betty Hom, MD
Co Author #1: Betty Hom MD
Co Author #2: Joshua Wilner MD
Senior Editor: Carolyn Landsberg, MD
Editor: Yu-Tsun Cheng, MD

Patient Presentation:
36-year-old male, avid weightlifter presented with subacute onset of atraumatic progressive pain of the right distal biceps with swelling and tightness.

History:
Pain comes on with weightlifting or washing his hair. Pain worsened with supination and elbow flexion. No bruising, weakness, or numbness/tingling. No fever or chills. He developed left forearm cellulitis 6 months prior, which improved with antibiotics. Bedside ultrasound revealed intact distal biceps tendon and swelling between the subcutaneous tissue and biceps muscle. He was diagnosed with biceps tendonitis and started conservative treatment. Right elbow, humerus, and shoulder x-rays were normal. Two days later, his pain worsened, and he was advised to go to the emergency department to rule out deep vein thrombosis (DVT) or compartment syndrome. He arrived afebrile without chest pain or dyspnea. Patient revealed he receives weekly testosterone injections, which he initially denied.

Physical Exam:
Vital signs were within normal limits. Normal heart and lung exams.
Musculoskeletal: Large muscle bulk of the bilateral upper extremities (BUE). Right biceps greater in size with increased firmness compared to the left. Compartments were soft. No overlying skin changes or pitting edema. No obvious mass or deformity. Tenderness to palpation over the right distal biceps tendon and muscle; no significant proximal tendon tenderness. Normal range of motion of the right shoulder. Mildly reduced right elbow flexion, otherwise normal elbow extension, supination, and protonation. Negative Speed's and Yergason's tests.
Neuro: 5/5 strength to BUE, including supination. Sensation intact.
Vascular: 2+ radial pulses bilaterally.
Skin: No erythema, warmth. No red streaking. No crepitus.

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