Author: Caleb Holder, DO
Co Author #1: Andrew Porter, DO
Senior Editor: Drew Duerson, MD
Editor: David Edwards, MD

Patient Presentation:
A 23-year-old right-handed baseball pitcher with history of humeral neck fracture status post repair as a child presented with left shoulder pain for the past 2 weeks.

History:
While bench-pressing weights, he felt a pop in his left shoulder with immediate pain. He was unable to play baseball and developed limited range of motion of the left arm. He was seen in the Emergency Department twice since time of injury, with normal vital signs and unremarkable x-rays of the shoulder. He was discharged in a sling with instructions to follow up for concerns of a proximal biceps tendon rupture based on exam. He was offered CT and ultrasound, but declined these due to cost. He was examined in the training room at 9 days post-injury, and his strength was 1/5 with elbow flexion. An MRI was ordered, but was pending. His pain was constant and uncontrolled with hydrocodone-acetaminophen every 4hrs. He was seen by the athletic trainer again one day prior to evaluation in clinic and was noted to have a small rash on his left shoulder Case Photo #1 . He was prescribed sulfamethoxazole/trimethoprim at double strength dosing and instructed to be seen in clinic. Review of previous imaging was done prior to his examination Case Photo #2 . Swelling worsened throughout his entire arm, with redness and inability to flex his arm at time of exam in clinic. Case Photo #3

Physical Exam:
Vitals: Temp 36.3 C, HR 93 beats/minute, BP 146/88 mm Hg, SPO2 97% on room air
General: Appeared fatigued, mild distress secondary to pain, left arm held in extension due to weakness and pain.
Cardiovascular: Regular rate and rhythm, no murmurs, 2+ distal pulses.
Respiratory: No respiratory distress, lungs clear to auscultation bilaterally
Musculoskeletal: Left upper extremity showed loss of biceps contour, significant swelling from the left trapezius and across the deltoid, down to the proximal forearm. Strength: 0/5 elbow flexion, 2/5 forearm supination, 4/5 shoulder abduction, 5/5 internal/external rotation of the shoulder. Very tense 3cm x 3cm erythematous, fluctuant mass near prior surgical incision over lateral deltoid.
Neurologic: Sensation intact through radial/ulnar/median distributions

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