| Nerve Entrapment
Disorders: Carpal Tunnel
Syndrome:
Repetitive work can cause pressure on
the median nerve in locations other than the wrist and can also affect other nerves in the
arm and hand.
Ulnar Tunnel Syndrome:
The ulnar nerve supplies sensation to
the ring and little fingers. Like the median nerve, it too can become trapped as a result
of repetitive stress, with subsequent loss of sensation in these fingers and the outer
half of the palm. This condition, known as ulnar tunnel syndrome.
Thoracic Outlet Syndrome:
Pinched nerves in the neck may also
cause weakness in the hands. A disorder known as thoracic outlet syndrome caused by
compression of nerves and blood vessels running down the neck into the arm can cause
symptoms very similar to CTS. The compression occurs at the first rib in the front of the
shoulder.
Diagnosis:
Electrodiagnostic Tests:
There are two common types of
electrodiagnostic tests: nerve conduction studies and electromyographies. The tests
analyze the electric waveforms of nerves and muscles to detect median nerve compression in
the carpal tunnel. To perform nerve conduction studies, surface electrodes are first
fastened to the hand and wrist. Small electric shocks are then applied to the nerves in
the fingers, wrist, and forearm to measure the speed of conduction of sensory and motor
nerve fibers. To perform electromyography, a fine sterile, wire electrode is inserted
briefly into a muscle and the electrical activity is displayed on a viewing screen. |
