The Elbow Flexion Test (EFT) is a common clinical assessment used by healthcare professionals to evaluate the health and function of the ulnar nerve. This nerve is susceptible to compression as it travels through the cubital tunnel. The test is specifically designed to stress the ulnar nerve at the elbow to determine if it is irritated or entrapped. Understanding what constitutes a normal outcome is central to interpreting the test’s results.
Why and How the Test is Performed
The primary goal of the Elbow Flexion Test is to provoke symptoms associated with ulnar nerve compression, often resulting in Cubital Tunnel Syndrome. Maximal elbow flexion narrows the space through which the ulnar nerve passes, physically tensioning the nerve and drawing the aponeurosis of the flexor carpi ulnaris muscle taut. This mechanical action reduces the volume of the cubital tunnel, which can irritate an already compromised nerve.
To perform the test, the patient is usually seated or standing. The examiner instructs the patient to hold the elbow in a position of maximal flexion, often combined with supinating the forearm and extending the wrist to further increase tension. The patient must hold this position for a specified duration, typically 60 seconds, while the examiner monitors for the onset of symptoms.
Criteria for a Normal Response
A normal, or negative, result is defined by the ability to maintain the required position for the full duration without the onset of specific neurological symptoms. A healthy individual should be able to sustain maximal elbow flexion for the entire minute of the common 60-second protocol. The most important criterion is the complete absence of paresthesia—the tingling, burning, or numbness sensation that indicates nerve irritation. These sensations would specifically occur in the sensory distribution of the ulnar nerve, including the little finger and the adjacent half of the ring finger.
The lack of this neurological feedback suggests the nerve has adequate physiological space and mobility within the cubital tunnel. While holding the position, some individuals may experience mild muscular fatigue or a generalized ache, but this discomfort is considered a normal response to sustained muscle contraction, not a positive test result. A healthy nerve is flexible and can temporarily stretch up to five millimeters to accommodate the change in joint position without triggering symptoms.
What Abnormal Results Indicate
An abnormal, or positive, result occurs if the patient experiences characteristic ulnar nerve symptoms before the required test duration is met. This finding is signaled by the reproduction of pain or the onset of paresthesia in the ring and little fingers. If the patient must stop the test early due to these symptoms, the result is considered positive.
The reproduction of these specific neurological symptoms is highly suggestive of ulnar neuropathy, commonly known as Cubital Tunnel Syndrome. The maximal elbow flexion further tightens the anatomical structures surrounding the nerve, such as the retinaculum, which is already pressing on a compromised nerve. The mechanism behind the abnormal finding is that the sustained tension and reduced space restrict the nerve’s blood supply, leading to localized ischemia and resulting tingling and numbness.