Atypical Presentations in Patients with Carpal Tunnel Syndrome: A Retrospective Study of 106 Patients

Background/Objectives: Carpal tunnel syndrome (CTS) is the most frequent entrapment neuropathy and is usually associated with classic sensory and motor findings. In rare cases, atypical presentations of CTS may occur, such as pruritus, Raynaud’s phenomenon (RP), and digital ulceration. Our objective is to describe the clinical and electrodiagnostic (EDX) features of patients with CTS who exhibited these uncommon presentations. Methods: This is a review of patients referred for EDX confirmation of CTS, who also had unusual features such as pruritus, RP, and/or digital ulceration over a 12½ year period (1 January 2013–31 July 2026). All patients underwent detailed clinical examination and EDX studies. Results: A total of 106 patients had evidence of CTS with uncommon features: pruritus in 92 (86.8%), RP in 8 (7.5%), digital ulceration in 4 (3.8%), and a combination of pruritus and RP in 1 (0.94%) and digital ulceration and RP in 1 (0.94%). Pruritus was associated with CTS in a total of 137 hands (48 patients unilateral and 45 patients bilateral). Of the 137 hands, the most common location of the pruritus was the palm in 72 (52.6%). A total of 132 (96.4%) of those patients had decreased pinprick sensation, and 21 (15.3%) had weakness and/or wasting of thenar muscles. CTS was graded as moderately severe in 67 (48.9%) of the 137 hands with pruritus. RP was associated with CTS in a total of 16 hands (4 patients unilateral and 6 patients bilateral). All 16 (100%) patients with RP had decreased pinprick sensation, and 3 (18.8%) patients had weakness and/or wasting of the thenar muscles. The CTS associated with RP was mild in 7 (43.8%) patients and moderate in 5 (31.2%). Ulcerative CTS was observed in a total of 7 hands (3 patients unilateral and 2 patients bilateral). All 7 patients with ulcerative CTS had either loss of sensation or hypoesthesia as well as weakness and/or wasting of the thenar muscles. The CTS was severe in all 7 of these patients. The severity of CTS varied by the type of CTS (pruritus, RP, and digital ulceration) (p-value < 0.001). Patients with digital ulceration had more severe symptoms than those with other presentations of CTS (p-value < 0.001). Patients with RP more frequently had mild symptoms compared to those with other presentations of CTS (p-value = 0.01). Conclusions: It is important for physicians of different specialties to be aware of rare, atypical clinical presentations of patients with CTS. These presentations include pruritus, RP limited to median nerve-innervated digits, and digital ulceration. These patients should be promptly referred for EDX studies to confirm the diagnosis of CTS.