[The role of electrophysiologic tests in the early diagnosis of posterior interosseous neuropathy in patients thought to have lateral epicondylitis].

OBJECTIVES

We investigated the role of electrophysiologic tests in determining posterior interosseous neuropathy (PIN) in patients with a preliminary diagnosis of lateral epicondylitis.

METHODS

Thirty-three patients (24 females, 9 males; mean age 49 years) with a preliminary diagnosis of lateral epicondylitis and 15 healthy controls (10 females, 5 males; mean age 48 years) underwent radial, median, and ulnar nerve conduction studies, electromyography (EMG) of some selected muscles, and measurements for grip strength. The duration of symptoms was less than a month in all the patients and no therapy was instituted.

RESULTS

A diagnosis of PIN was made in 22 patients (66.7%). The mean ages of the patients with and without PIN were 45 and 51 years, respectively. The mean grip strengths did not differ significantly between the patients and controls, and between the right and left hands. All the patients responded well to conservative treatment.

CONCLUSION

Electrophysiologic tests may be necessary and beneficial in the differential diagnosis of PIN in patients unresponsive to treatment for lateral epicondylitis of early stage.