Delayed Radial Nerve Palsy Following a Low-Impact Mechanical Fall Managed With Early Ultrasound-Guided Hydrodissection: A Case Report.

A 43-year-old male presented to the emergency department due to progressive weakness of the left hand and wrist following blunt trauma to the elbow around three weeks prior to evaluation. He was initially evaluated at the time of injury with radiographs of the elbow and forearm, which were reported to be normal. Due to worsening weakness, he sought care at additional emergency departments and with a neurologist who performed a CT, repeat radiographs, and eventually an MRI of the elbow, all of which revealed no acute findings. At our facility, point-of-care ultrasound evaluation of the elbow demonstrated radial nerve compression just proximal to the joint. Ultrasound-guided hydrodissection of the radial nerve was performed, after which the patient showed improvement in range of motion and strength over the following days. With early initiation of physical therapy, the patient regained full range of motion against gravity within one month and achieved complete recovery within three months. Recognition and prompt management of peripheral nerve compression requires a multidisciplinary approach, involving emergency medicine, physical medicine and rehabilitation, and neurology. Early intervention may help prevent long-term dysfunction and aid in more rapid recovery of compressive neuropathies.