Foraminal lumbar disc herniation. Experience with 83 patients.

STUDY DESIGN

This study analyzed a series of 83 patients operated on for foraminal lumbar disc herniation.

OBJECTIVES

This study sought to develop clinical and radiologic diagnoses, evaluate interlaminar and extra-articular exposures, and evaluate postoperative results.

SUMMARY OF BACKGROUND DATA

Some authors have reported a specific clinical syndrome, but other reports have indicated the clinical picture is indistinguishable from usual posterolateral disc herniation. Surgical management often has been compared between the interlaminar and extra-articular approaches.

METHODS

Clinical findings were reviewed. All patients were evaluated with computed tomography, but radiologic diagnosis required computed tomographic discography for 26 patients. Interlaminar exposure with partial medial facetectomy was performed in 73 patients and an extra-articular approach was necessary in 10 patients. Postoperative results were evaluated with a 2-year follow-up.

RESULTS

Foraminal lumbar disc herniations have a specific clinical picture, particularly severe radicular signs. Precise preoperative radiologic evaluation is essential for successful operative procedure. Postoperative results were good in 76% of the patients. The other patients felt mild residual radicular pain, although no residual root compression was found on postoperative computed tomography. Only 21% of the patients that had a radicular deficit recovered totally.

CONCLUSIONS

Foraminal lumbar disc herniation involves characteristic clinical features. Radiologic diagnosis requires high-resolution computed tomography, computed tomographic discography, or magnetic resonance imaging. Most foraminal lumbar disc herniations are reached through the interlaminar exposure extended to the upper lamina and medial facet without total facetectomy. An extra-articular approach should be reserved for extra-foraminal herniations.