The Importance of Preserving Disc Structure in Surgical Approaches to Lumbar Disc Herniation

STUDY DESIGN: This study examined the clinical and radiographic results in patients with lumbar disc herniation treated surgically with one of four procedures: two different methods of herniotomy using a posterior approach and two different methods of percutaneous nucleotomy. OBJECTIVES: The authors goal was to identify the structural changes in the disc after each of the procedures and to correlate them with the clinical outcome. SUMMARY OF BACKGROUND DATA: The details of herniotomy procedure via a posterior approach or by percutaneous nucleotomy as described by many authors have not been consistent. Furthermore, previous reviews of these studies have been less than satisfactory. METHODS: One hundred fifty-seven herniotomies using a posterior approach and 94 percutaneous nucleotomies were studied with a follow-up of at least 2 years. Each of these groups was divided into two subgroups to evaluate the role of the remaining nucleus pulposus in the central area of the disc. RESULTS: Changes seen in imaging studies, such as a decrease in disc height and an increase of intervertebral instability in plain radiographs and a decrease in signal intensity of the disc in magnetic resonance images, were significantly less common in the subgroups of herniotomy and percutaneous nucleotomy in which the nucleus pulposus in the central area of the disc was preserved when compared with the subgroups in which a complete removal of the disc was attempted. The changes seen in the imaging studies were significant in patients younger than 40 years of age and correlated closely with the clinical results. CONCLUSIONS: Preserving the nucleus pulposus during the surgical treatment of lumbar disc herniation in patients younger than 40 years of age resulted in better radiographic and clinical results.