Reliability of Two Tests for Cubital Tunnel Syndrome
Doctors often poke and prod patients to find out exactly what's causing their pain or symptoms. In the case of nerve entrapment at the elbow, two tests are often used to diagnose cubital tunnel syndrome (CuTS). A false positive test may result in unnecessary nerve testing and even surgery. False positive occurs when the test is positive but there's nothing really wrong with the elbow.
In this study, the Tinel and elbow flexion tests are checked for reliability. The Tinel test for the ulnar nerve applies tapping pressure on the inside of the elbow where the nerve is close to the surface. A positive test is if two taps causes numbness or tingling at the elbow, down the arm, or into the hand.
In the second test (elbow flexion) the patient bends the elbow fully with the upper arms at the side. Again, numbness and tingling from the ulnar nerve after one. two, or three minutes is a positive test.
These two tests were given to 100 healthy college students who had no previous history or signs of ulnar nerve entrapment. A total of 200 elbows were tested. One doctor did all the testing.
The Tinel test was positive in 36 percent of the elbows. The elbow flexion test was positive 20 percent of the time. The authors believe these are false positive responses in this group of subjects. Neither test is useful to evaluate for possible CuTS.
At the present time no single test can be used to diagnose CuTS. These two tests can still be used but the result must be viewed with caution. History, physical exam, and other tests such as nerve conduction velocity (NCV) tests are needed to confirm or rule out CuTS as the problem.
Stuart H. Kuschner, MD, et al. Evaluation of Elbow Flexion and Tinel Tests for Cubital Tunnel Syndrome in Asymptomatic Individuals. In Orthopedics. April 2006. Vol. 29. No. 4. Pp. 305-308.