Cubital tunnel syndrome caused by simultaneous intraneural and extraneural ganglion cysts of the ulnar nerve: a rare case report
Quyet Tran, Thang Vu Duc, Phan Nguyen Van, Thinh Le Duc, Hien Tran Thi ThuIntroduction and importance:
Intraneural ganglion cysts of the ulnar nerve are an uncommon cause of cubital tunnel syndrome (CuTS). Coexisting intraneural and extraneural ganglion cysts affecting the same nerve are exceptionally rare. Although the articular (synovial) theory is widely accepted, the optimal surgical management remains controversial.
Presentation of the case:
A 71-year-old man presented with progressive CuTS caused by simultaneous intraneural and extraneural ganglion cysts of the ulnar nerve at the elbow. Ultrasound and magnetic resonance imaging (MRI) revealed multiple cystic lesions compressing the ulnar nerve, without a clearly identifiable articular branch connection. The patient underwent intraneural cyst decompression by longitudinal epineurotomy, excision of adjacent extraneural cysts, and anterior subcutaneous transposition of the ulnar nerve, without articular branch exploration or ligation.
Clinical discussion:
Symptoms resolved completely after surgery. Follow-up ultrasound at 3 months and MRI at 6 months confirmed complete cyst resolution without recurrence.
Conclusion:
This case highlights the rare coexistence of intraneural and extraneural ganglion cysts of the ulnar nerve. In selected patients without demonstrable joint communication, cyst decompression, excision, and nerve transposition may provide favorable short-term outcomes without routine articular branch exploration.