Carpal tunnel syndrome | Sparing of ring and little fingers, thenar muscle wasting, lack of interossei wasting, positive Phalen test and Durkan compression test |
Cervical radiculopathy | Neck pain, reduced range of movement in the neck, sensory changes proximal to the wrist crease |
Guyon canal syndrome | Sparing of sensation on the dorsum of the hand |
Brachial plexus injury or neuritis | History of trauma, more widespread neurologic symptoms and signs |
Thoracic outlet syndrome | Pain is a predominant feature; discoloration of the hand; symptoms related to strenuous exercise |
Syringomyelia | Widespread neurologic symptoms and examination findings; cape-like loss of pain and temperature sensation |
Pancoast tumour | Substantial smoking history; chest pain, breathlessness; hemoptysis; constitutional symptoms of malignancy; Horner syndrome |
Less frequent causes include systemic conditions such as Guillain–Barré syndrome, motor neuron disease or polyneuropathy | Bilateral symptoms or unusual patterns of neurologic signs on examination |