A Rare Case of Cervical Spinal Arteriovenous Malformation in an Adolescent Presenting with Winged Scapula: A Rare Case Report.

Spinal arteriovenous malformations (SAVMs) are rare vascular lesions .They are basically anomalous connections between arteries and veins within the spinal canal and often result in progressive neurological deficits. Cervical intramedullary arteriovenous malformations (AVMs) are uncommon, and their presentation with scapular winging is extremely rare. A 16-year-old right-handed male presented to us with a 3-month history of right shoulder pain, weakness, and limited overhead movements that initially started after lifting a heavy object. On examination, right scapular winging and serratus anterior atrophy were noted along with a positive Hoffmann's sign. The neurological deficits were predominantly confined to the right upper limb, whereas the lower limbs were spared. Electrodiagnostic studies showed chronic neurogenic changes in the serratus anterior, and MRI revealed an intramedullary cervical spinal lesion extending from C3 to C5 with cord expansion, a hypointense rim suggestive of hemosiderin, and patchy post-contrast enhancement. The patient underwent C3 to C5 laminectomy with excision biopsy. Histopathology confirmed a benign vascular malformation consistent with spinal AVM. Sensory function improved postoperatively, though the right upper limb weakness persisted. Physiotherapy was advised with regular neurosurgical follow-up at the time of discharge. This case illustrates a rare presentation of cervical arteriovenous malformation presenting as scapular winging because of long thoracic and phrenic nerve damage. It emphasizes a detailed neurological examination, identification of upper motor neuron signs, and early use of advanced imaging in atypical presentations. Early detection and surgical intervention are critical to prevent irreversible neurological deficits and thereby improve outcomes in young patients with such rare spinal vascular lesions.