Complicated Distal Biceps Tendon Repair with Resulting Development of Complex Regional Pain Syndrome Resolved with Median and Radial Nerve Hydrodissection: A Case Report

Case Diagnosis: 49-year-old male with complex regional pain syndrome (CRPS) type II due to median and radial nerve injury following complicated biceps tendon repair experienced symptom reduction with hydrodissection.

Case Description or Program Description: The patient, who underwent repair of left biceps tendon rupture complicated by abscess 2 years prior, presented with severe radiating left arm pain since surgery. Pain was accompanied by allodynia, hyperalgesia, hair loss, and nail-thickening. He was diagnosed with CRPS and his pain was poorly-managed with 6 stellate ganglion blocks, pregabalin, and opiates prior to presentation.

Setting: Outpatient PM&R Clinic

Assessment/Results: Left upper extremity electrodiagnostic studies demonstrated decreased radial sensory amplitude and median nerve slowing across the forearm. Ultrasound of the median and radial nerves adjacent to surgical site revealed hypoechoic swelling of the nerves, which was painful and reproduced patient's symptoms. Ultrasound-guided hydrodissection was performed at the median and radial nerve with 10cc lidocaine and saline with 12.5% dextrose solution. 1 month later, he had 50% reduction in symptoms, and no longer required pregabalin. Repeat hydrodissection was performed with higher volume, 20cc, and patient started occupational therapy. 8 weeks later, he reported 90% reduction in symptoms, no longer requiring opioids, with increased strength and unrestricted return to work.

Discussion (relevance): Post-operative nerve pain can be difficult to treat; many first-line treatment options are accompanied by serious side-effects. Thorough investigation of neuropathic pain involves a multifaceted approach including electrodiagnostic studies and ultrasound. Treatment with non-pharmacological treatments such as hydrodissection should be considered, especially when first-line treatments fail.

Conclusions: Post-operative nerve pain deserves thorough work-up and ongoing evaluation. CRPS type II can develop from entrapment neuropathy and differentiating type 1 from type 2 is important to guide treatment. Electrodiagnostic studies are the gold standard for diagnosis of nerve injury; however, ultrasound is a validated tool for diagnosis of nerve entrapment and is useful for guiding treatment with hydrodissection.