(1)
Department of Neurosurgery, University of Wisconsin, Madison, WI, USA
21.1 Case Presentation
A 53-year-old male presents with left forearm pain and limited finger extension. This started 3.5 years ago following a car accident. The pain is a discomfort on the extensor surface of the upper forearm and radiates slightly cranially and caudally. It is worse in cold weather, and with using the arm, especially holding the phone to his ear. It is improved with gabapentin. There is no tingling or numbness. PMH: asthma, hypertension, Lyme’s disease, arthritis. PSH: lumbar laminectomy, carpal tunnel release. FH: diabetes in both grandmothers and a sister, lung cancer in the mother, abdominal aortic aneurysm in the father and the paternal grandfather. Socially, he has smoked 1.5 packs of cigarettes per day for 40 years and does not drink alcohol. On examination, finger extension at the MPJ 4, EPL 4, abductor pollicis longus 4+, the remaining muscle groups are 5/5. Sensation is intact to light touch. DTRs are 2+ and symmetric. There is percussion tenderness over the extensor surface of the upper forearm but no Tinel’s sign.
Fig. 21.1
21.2 Questions
- 1.
What is the differential diagnosis?
- 2.
What studies do you need?
- 3.
What do you recommend?
Answers
- 1.
Differential diagnosis: PIN entrapment, most likely, typical appearance of the hand (Fig. 21.1) with radial deviation with wrist extension due to loss of ECU while the radial extensors are intact. Although it can cause pain, the nerve has no cutaneous distribution; therefore, there is no sensory loss. Radial tunnel syndrome is predominantly a pain syndrome associated with sensory changes in the radial n distribution. Lateral epicondylitis (tennis elbow) is very similar to radial tunnel, with tenderness predominantly over the lateral epicondyle [1]. This could also be a traumatic injury to the radial n (history of car accident), neuropathy from Lyme’s disease [2], or multifocal motor neuropathy (MMN ) with conduction block.Stay updated, free articles. Join our Telegram channel
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