Investigations

In patients with a diagnosis of CTS, identifying contributing factors (e.g. - hypothyroidism, diabetes, inflammatory conditions) and treating them may contribute to an improvement or resolution of symptoms. Routine screening of CTS patients in the absence of other clinical evidence of secondary causes is neither useful or cost effective (1,2).

Electrophysiological studies are not required to make an initial diagnosis of carpal tunnel syndrome or to initiate management in the primary care setting. Electromyography and nerve conduction studies are

• generally useful in specialist environment for patient selection for surgery, and for evaluation of complex cases, relapse of symptoms, or recurrence
• used to confirm a median nerve lesion, localise the lesion to the carpal tunnel rather than to another site such as the cervical spine, exclude other causes of neuropathy, and form a baseline for nerve function before treatment

Ultrasonography and MRI may be beneficial in some cases but its use

Reference:

• (1) Middleton SD, Anakwe RE Carpal tunnel syndrome. BMJ. 2014;349:g6437
• (2) Burton C, Chesterton LS, Davenport G. Diagnosing and managing carpal tunnel syndrome in primary care. Br J Gen Pract. 2014;64(622):262-3.