The external fixation test of the lumbar spine. 30 complications in 25 of 100 consecutive patients.

We retrospectively analyzed the rate and character of complications in a series of 100 consecutive external fixation tests during 1985-1991. There were 30 complications in 25 patients. The most common was pin tract infection, which was definite in 12 cases and probable in 6. Although 12 patients developed complications that resulted in removal or reapplication of the device. 8 cases had an incorrect position of a Schanz screw; 3 of these had neurological complications. The only variable having a significant association with complications was the duration of the test. Because of this complication rate, the indications for the test should be carefully considered.