Consistency of history taking and physical examination in patients with suspected lumbar nerve root involvement.

STUDY DESIGN

A cross-sectional study of interobserver variability in primary care patients.

OBJECTIVE

To investigate the consistency of signs and symptoms of nerve root compression in primary care patients with pain irradiating pain into the leg (sciatica).

SUMMARY OF BACKGROUND DATA

The literature does not report on all the clinical tests for nerve root compression. In previous studies, most patients had low back pain with no irradiation. Often, little information on examination technique, proportion of positive test results, or clinical patient characteristics was provided.

METHODS

A random selection of 91 patients was investigated by a neurologist-resident couple. Agreement percentages, proportions of positive test results, and kappas were calculated.

RESULTS

The kappa of the overall conclusion after the history taking was 0.40, increasing to 0.66 after physical examination. Kappas were good for decreased muscle strength and sensory loss (0.57-0.82), intermediate for reflex changes (0.42-0.53), and poor for the examination of the lumbar spine (0.16-0.33). The straight leg raising, crossed straight leg raising, Bragard's sign, and Naffziger's sign were the most consistent nerve root tension signs (> 0.66).

CONCLUSIONS

Two clinicians disagreed on the presence of nerve root involvement in one of four patients after history taking, and in one of five patients after physical examination. For a more consistent overall diagnosis, the physician probably should put more emphasis on the history of pain on coughing-straining-sneezing, a feeling of coldness in the legs, and urinary incontinence. The investigation of paresis, sensory loss, reflex changes, straight leg raising, and Bragard's sign provide the most consistent results.