QUANTITATIVE OUTCOME AND RADIOGRAPHIC COMPARISONS BETWEEN LAMINECTOMYAND LAMINOTOMY IN THE TREATMENT OF ACQUIRED LUMBAR STENOSIS

OBJECTIVE: The objective of this study was to conduct a comparative qu antitative analysis of outcomes, radiographic findings, and magnetic r esonance imaging results after laminectomy or laminotomy was performed for patients with lumbar stenosis. Such an analysis had not previousl y been conducted. METHODS: Twenty-six patients with no exclusion crite ria who were treated surgically for acquired stenosis at the Division of Neurological Surgery at The Ohio State University from 1990 to 1993 were studied retrospectively. At follow-up examinations, each patient completed a detailed questionnaire that included visual analog scales , functional assessments, and the medical outcome study short form hea lth survey, SF-36. Each patient underwent plain static and dynamic rad iography that detailed vertebral body sagittal listhesis and rotation and magnetic resonance imaging that evaluated dural sac compression. R ESULTS: The mean follow-up duration was 36.7 months. Good outcome was defined by the presence of three criteria: no greater than mild leg pa in (Grades 0-4), the ability to walk more than one block without devel oping lower extremity pain, and the ability to walk without assistance devices. Fifty-eight percent of the patients who had undergone lamine ctomies and 50% of the patients who had undergone laminotomies had goo d outcomes. All were judged to have had adequate decompression. The av erage maximum postoperative listhesis was 17.3 +/- 9.9% in the laminec tomy group and 17.6 +/- 12.5% in the laminotomy group. In contrast to some previous studies, pre-or postoperative listhesis was not statisti cally related to outcome in either group. Patients in each poor outcom e category seemed to have worse comorbid medical conditions than did p atients in the good outcome category. The SF-36 measurements of poor f unctioning because of health factors and bodily pain correlated somewh at with poor outcomes in the patients who had undergone laminectomies. In patients who had undergone laminotomies, the only statistically si gnificant finding among the outcome groups was the effect of poor emot ional health on activity for the patients with poor outcomes. CONCLUSI ON: This study indicates that laminotomy can adequately decompress lum bar canal stenosis that laminectomy and laminotomy have the same degre e of postoperative listhesis, and that the quantitative outcome of any treatment for lumbar stenosis is dependent not only on surgical facto rs but also on comorbid physical and psychological factors.