Elbow Orthopaedic Test: Wartenberg's Sign

Wartenberg's Sign, also known as "ulnar drift," is a physical examination maneuver used to assess for the presence of ulnar nerve compression or injury. The test involves observing the patient's fingers for an involuntary abduction or deviation of the fifth digit away from the other fingers.

Procedure:

1. Position the patient comfortably so that their hand is easily accessible and visible.
2. Ask the patient to place their hand flat on a table with their fingers extended and close together.
3. Observe the position of the fingers, specifically noting the position of the fifth digit.
4. Ask the patient to try to bring their fingers together or close their hand into a fist while you gently resist the movement.
5. Observe the position of the fingers again, paying particular attention to the position of the fifth digit.
6. Look for any deviation or abduction of the fifth digit away from the other fingers.
7. Repeat the test on the other hand for comparison, if necessary.

A positive Wartenberg's Sign test is characterized by the fifth digit abducting or drifting away from the other fingers, often due to weakness or paralysis of the interossei and lumbrical muscles innervated by the ulnar nerve.

There is no definitive sensitivity or specificity reported for Wartenberg's Sign test, as it is primarily a clinical observation used to aid in the diagnosis of ulnar nerve injury or compression.

References:

1. Bozentka DJ. Ulnar nerve anatomy. Hand Clin. 2004;20(3):229-238. doi: 10.1016/j.hcl.2004.03.001
2. Kline DG, Kim D. Ulnar nerve entrapment at the elbow. Neurosurgery. 2002;50(1):26-31; discussion 31-32. doi: 10.1097/00006123-200201000-00006
3. Spinner M. Management of peripheral nerve problems. Philadelphia: WB Saunders; 1998.