Carpal Tunnel Syndrome

Procedure

Patient seated with the forearm supinated and the wrist in neutral, resting on a table. Tap lightly four to six times over the median nerve at the proximal wrist crease, between palmaris longus and flexor carpi radialis, using a fingertip or reflex hammer.

Positive Finding

Tingling or paraesthesia spreading into the median nerve distribution (thumb, index, middle and radial half of the ring finger). Local tenderness at the tapping point alone does not count.

Sensitivity / Specificity

Reference: Dabbagh A, MacDermid JC, Yong J, Packham TL, Grewal R, Boutsikari EC. Diagnostic Test Accuracy of Provocative Maneuvers for the Diagnosis of Carpal Tunnel Syndrome: A Systematic Review and Meta-Analysis. Phys Ther. 2023;103(6).

Interpretation

A positive sign supports median nerve irritation at the carpal tunnel. A negative sign does not exclude carpal tunnel syndrome. Interpret it with the symptom pattern (night waking, shaking the hand out), sensory testing and the other provocation tests; nerve conduction studies confirm the diagnosis when management depends on it. The reference previously shown for this test was a paper on a different body region that does not report on this test; it has been withdrawn. Figures are pooled from a 2023 meta-analysis that excluded studies using healthy controls. Studies comparing patients with healthy volunteers report much higher specificity; those figures overstate the test in clinic.

Procedure

Patient rests both elbows on a table with the forearms vertical and lets the wrists drop into full flexion under gravity. Hold for up to 60 seconds. Do not force the wrists or press the backs of the hands hard together, which adds compression unrelated to the test.

Positive Finding

Numbness or paraesthesia in the median nerve distribution within 60 seconds. Record the time to onset.

Sensitivity / Specificity

Reference: Dabbagh A, MacDermid JC, Yong J, Packham TL, Grewal R, Boutsikari EC. Diagnostic Test Accuracy of Provocative Maneuvers for the Diagnosis of Carpal Tunnel Syndrome: A Systematic Review and Meta-Analysis. Phys Ther. 2023;103(6).

Interpretation

A positive test supports carpal tunnel syndrome, but on its own it changes the probability only a little. Use it as one part of a cluster with the history, sensory testing and Tinel's sign rather than as a stand-alone test. The reference previously shown for this test was a paper on a different body region that does not report on this test; it has been withdrawn. Figures are pooled from a 2023 meta-analysis that excluded studies using healthy controls. Individual studies varied widely (sensitivity 12–92%, specificity 30–95%), so no single study figure should be quoted.

Procedure

Patient seated with the forearm supinated and the wrist in neutral. Press firmly with both thumbs directly over the carpal tunnel, just distal to the distal wrist crease, and hold for up to 30 seconds.

Positive Finding

Numbness, tingling or pain in the median nerve distribution within 30 seconds.

Sensitivity / Specificity

Reference: Dabbagh A, MacDermid JC, Yong J, Packham TL, Grewal R, Boutsikari EC. Diagnostic Test Accuracy of Provocative Maneuvers for the Diagnosis of Carpal Tunnel Syndrome: A Systematic Review and Meta-Analysis. Phys Ther. 2023;103(6).

Interpretation

A positive result supports median nerve compression at the carpal tunnel. Results vary widely between studies, so do not rely on it alone. The reference previously shown for this test was a paper on a different body region that does not report on this test; it has been withdrawn. Range across five studies that compared patients with other symptomatic patients (Dabbagh 2023, Table 3). Specificity above 85%, often quoted, comes from comparisons with healthy volunteers.

Procedure

Patient's eyes closed, hand supported palm up. Touch the fingertip pulp with one or two blunt points of a calibrated discriminator, placed lengthways along the finger and pressed only until the skin just blanches. Start with a wide gap and narrow it, mixing one- and two-point touches at random. Test the thumb, index and middle fingertips and compare with the other hand and with the ulnar-supplied little finger.

Positive Finding

The patient cannot reliably tell two points from one at a gap clearly wider than on the other hand or on the little finger.

Interpretation

Static two-point discrimination usually stays normal until nerve compression is advanced, so a normal result does not exclude carpal tunnel syndrome. An abnormal result suggests established sensory loss; record it as a baseline and include it in any referral.

Procedure

Palpate along the median nerve at the wrist, between palmaris longus and flexor carpi radialis, at and just proximal to the wrist crease, with firm but comfortable pressure. Compare with the other wrist.

Positive Finding

Reproduction of the patient's median nerve symptoms, or clearly more tenderness than on the unaffected side.

Interpretation

Supports median nerve irritation at the wrist, but tenderness here can also come from the flexor tendons or the wrist joint. Use it alongside the provocation tests rather than on its own.

Procedure

Patient supine. Stabilise the shoulder girdle to stop it elevating, then add in order: shoulder abduction to about 110°, wrist and finger extension, forearm supination, shoulder lateral rotation and elbow extension. Then add cervical side-flexion away from and towards the tested side to see whether the symptoms change.

Positive Finding

Reproduction of the patient's arm or hand symptoms that changes with cervical side-flexion (or another movement away from the symptomatic area), and differs from the other side.

Interpretation

A positive test shows increased mechanosensitivity of the median nerve somewhere along its course; it does not locate the problem to the carpal tunnel. It is often positive in cervical radiculopathy and other proximal nerve problems, so use it to help tell these apart rather than to diagnose carpal tunnel syndrome.