(Kiosk 2) Role of Dynamic Ultrasound in the Diagnosis of Snapping Triceps Syndrome in a 19-year-old Male

Case Diagnosis: 19-year-old male with snapping triceps syndrome (STS)

Case Description: A 19-year-old right-hand dominant male who enjoys weightlifting presented with eight months of insidious onset medial elbow snapping with pain greater on the right than the left. Symptoms were reproduced during upper extremity exercises, namely dips, and prompted him to discontinue such exercises. He additionally reported a burning sensation radiating from the medial epicondyle to the medial forearm for the past two months. He denied trauma, numbness, weakness, or neck pain. He was previously seen by orthopedics who performed an MRI of the right elbow which showed normal results for his age. On examination, no skin changes or atrophy were noted. There was full active and passive range of the neck and elbow. Dural tension and Tinel’s at the elbow were negative. Strength, sensation, and reflexes were intact. A painful click in the region of the medial epicondyle was reproduced with tricep dips.

Discussion: STS is a rare cause of medial elbow discomfort. Its characteristic features are often missed by static imaging like MRI. While studies support the advantages of dynamic ultrasound assessment in diagnosing STS, a literature review reveals no reports of ultrasound to assess STS pathology during functional movements that provoke symptoms.

Setting: Outpatient Clinic

Assessment/Results: Electrodiagnostic testing showed no evidence of radiculopathy or peripheral mononeuropathy. Ultrasound of the elbow in active flexion demonstrated ulnar nerve subluxation followed by medial head triceps subluxation over the medial epicondyle bilaterally. Subluxation increased when a dip maneuver was simulated, correlating with patient symptoms. Treatment options were reviewed. The patient proceeded with bilateral ulnar nerve decompressions at the elbow with transposition and medial head triceps centralization, resulting in symptom resolution.

Conclusion: This case highlights the benefit of ultrasound to diagnose STS provoked during functional movements that reproduce patient symptoms.