The pathology of the ulnar nerve in acromegaly

Acromegalic patients may complain of sensory disturbances in their hands. Cubital tunnel syndrome, the ulnar nerve neuropathy at the cubital tunnel (UCT), in acromegalic patients has never been reported.

To describe and assess the prevalence of UCT in acromegalic patients and the effects of 1 year of therapy on UCT.

We examined prospectively 37 acromegalic patients with no history of polyneuropathy, acute trauma at the elbow, no diabetes or hypothyroidism with clinical examination, nerve conduction studies (NCS), and high-resolution ultrasound (US). A control group was made by 50 volunteers. The local ethics committee approved the study and written informed consent was obtained from all subjects involved in the study.

Clinical history, physical examination, NCS, and US were used to diagnose UCT at the beginning of the study and after 1 year.

In 8 of 37 patients, a diagnosis of UCT was made at the beginning of the study reflecting a prevalence of 21%. After 1 year, 5 of 8 (62.5%) patients reported clinical and NCS improvements and evident US reduction of nerve cross-sectional area (CSA; 16.7+/-2.9 mm(2) vs 12.2+/-3.1 mm(2); P<0.001). In 3 of 8 (37.5%) patients, the UCT was unchanged. Ulnar nerve CSA was significantly increased in acromegalic patients with UCT (16.7+/-2.9 mm(2) vs 11.1+/-2.3 mm(2); P<0.047).

Ulnar neuropathy could occur in acromegalic patients and can improve in 62% of cases with disease control. Due to the different management and therapeutic approach, it would be important to make differential diagnosis between cubital and carpal tunnel syndrome in acromegaly.