Dry Gangrene From Transient Vaso-Occlusion in the Setting of Right-Sided Brachial Plexus Paralysis.

An 81-year-old woman with chronic right-sided motor and sensory neuropathy, a result of radiation-induced brachial plexus syndrome, presented with an asymptomatic degloving injury of her distal right index finger. This was rapidly followed by the onset of dry gangrene in both the index and middle fingers. The patient reported no history of trauma or thermal injury, noting that her hand was normal before sleep and that she discovered the injury upon awakening. Examination revealed circumferential skin loss on the index finger and dusky discoloration with bullae on the middle finger. Despite these findings, the right hand was warm and well perfused.  An extensive diagnostic evaluation, including echocardiography, CT angiography, Doppler studies, infectious and autoimmune workups, and skin biopsies, effectively ruled out embolic, infectious, and vascular etiologies. Given the absence of vascular obstruction and the patient's history of waking with her arm in hyperflexed positions, the cause was determined to be pressure-induced transient ischemia. This case represents the first documented instance of pressure-induced dry gangrene in the context of brachial plexus syndrome of the upper extremity since 1873. It underscores the critical importance of considering pressure-induced ischemia in patients with profound neuropathy, where a lack of protective sensation can lead to prolonged, unnoticed compression. Prompt recognition of such cases can prevent unnecessary interventions and guide appropriate management.