476 - Triple Mononeuropathy of Distal Median, Radial & Ulnar Nerve after Untreated Upper Extremity Compartment Syndrome: A Case Report

Case of a 30 y/o right-handed female without PMHx presented to EDX clinic due to subacute left-hand weakness after suffering a MVA for which she sustained Traumatic Brain Injury that required admission to ICU and mechanical ventilation. At discharge, the patient developed worsening swelling, paresthesias & pain on distal Left UE, that was partially treated with oral medications. Afterwards she reported Lt UE weakness and numbness in distal forearm, wrist and hand. Initial Physical Examination was remarkable for left claw hand w/ marked muscle atrophy & contracture at forearm and hand. Also severely restricted AROM at digits 4th/5th, limited wrist flexion and extension. Strength was found 1/5 distally & 3/5 at Elbow. Decreased sensation at C8 distribution. NCV/EMG showed: median motor neuropathy with axonal loss proximal to pronator teres, ulnar sensory motor axonal loss proximal to FCU muscle & Radial sensory motor neuropathy with worse affection on PIN innervated muscles.

Discussions: This case highlights the complexity of managing neuropathies, in particular involving multiple nerve injuries. This case of triple mononeuropathy underscores the importance of early recognition and intervention of a sub-acute compartment syndrome to prevent long-term functional deficit. The absence of brachial plexus involvement suggests the deficit is a sequela of the aforementioned diagnosis.

Conclusions: Patients admitted due to trauma have to be monitored closely for the possibility of developing compartment syndrome even in the absence of a fracture, due to the irreversible nerve damages it may induce if not treated promptly. A triple mononeuropathy in the UE due to compartment syndrome, has not been documented to the best of our knowledge, until now.