Carpal tunnel syndrome (CTS). The condition affects approximately 1 % of the general population and 5 % of the working population engaged in repetitive motion and grasping activities. Reports of prevalence of up to 25 % or more have been made for full-time computer operators.

Length of symptoms, sensory distribution of symptoms, history of dropping things, occupation or activity, nighttime symptoms (or worse at night, often needing to shake or wring the hands out vigorously), previous treatments (corticosteroid injection, wrist splints), and hand coordination. Of course, complete medical and surgical histories are also extremely important.

A blank hand diagram is given to the patient to delineate the bothersome areas front and back. Patients who diagram a median nerve distribution or close to it (the volar/palmar 3¹/₂ digits – thumb, index, middle, and half of the ring) are very likely to have carpal tunnel syndrome.

Tinel’s sign and Phalen’s test. Tinel’s sign is elicited by gently percussing over the median nerve at the carpal tunnel. A positive sign is present if the patient describes an electrical shock sensation in the median nerve distribution. Phalen’s test is performed by having the patient place the dorsal sides of each hand against each other in a position of maximal wrist flexion for 30–60 s. The test is considered positive if the patient reports new or worsening paresthesias in the median nerve distribution of the affected hand(s). Both tests have variable sensitivity and specificity.

Durkan’s involves squeezing the patient’s wrist with direct compression over the median nerve at the carpal tunnel using the examiner’s thumb. A positive test is obtained if the patient reports new or worsening numbness or tingling in some portion of the median nerve sensory distribution to the hand within 30–60 s.

Durkan’s median nerve compression test is thought to be the most sensitive for CTS.

Proximal median nerve compression at the elbow often referred to as pronator syndrome, acute carpal tunnel syndrome, traumatic median nerve injury, or median nerve tumor (e.g., schwannoma).

The palmar cutaneous branch of the median nerve branches prior to the carpal tunnel and travels above the transverse carpal ligament. It innervates the skin over the thenar eminence. Thus typical carpal tunnel syndrome will not show sensory dysesthesias in this area, whereas pronator syndrome will.

Much like the straight leg raise for sciatica of the lumbar spine, Spurling’s test may be used to elicit cervical root pathology (radiculopathy). The patient is asked to extend the neck, tilt and turn the head laterally to the affected side to determine if the hand dysesthesias occur or worsen with the maneuver.

Thoracic outlet syndrome involves compression of the lower brachial plexus (ulnar symptoms predominate) or compression of the subclavian vessels between the anterior and middle scalene muscles, often associated with a cervical rib (check x-ray for this). Two classic tests are mentioned, Adson’s and Wright’s, both of which are frequently confused with the more useful Spurling’s test used for cervical radiculopathy. Adson’s test involves extension of the shoulder with the neck turned toward the affected side and may reproduce symptoms or cause reduction or loss of the pulse at the wrist. Wright’s test involves abduction and external rotation of the shoulder with the neck rotated away from the affected side and may similarly reproduce symptoms or cause reduction or loss of the pulse at the wrist.