Abstract
BACKGROUND: Various tumors and tumor-like disorders, originating from the neural sheath, as well as other types, may affect the brachial plexus region. Due to the infrequent presentation, brachial plexus palsy caused by spontaneous hematoma in patients with hemophilia might miss the treatment by early surgical decompression and progress to permanent nerve damage. CASE SUMMARY: The case reported here was a 30-year-old man with hemophilia, as well as both sensory and motor dysfunction of the left upper extremity. A presumptive diagnosis of brachial plexus tumor was initially made, which was subsequently confirmed to be an organized chronic hematoma rather than a neoplasm. The hemophilia-induced expanding hematoma compressing the brachial plexus was considered to be the main reason for the patient's complaints. The clinical symptoms were alleviated and the involved nerves partially recovered at a follow-up of 1 year. CONCLUSION: Early surgical intervention is crucial and it seems to be an essential precondition for recovery of nerve function in brachial plexus lesions.