The Influences of the Clinico-Radiological Factors in Predicting the Intra-operative Difficulties in single Disc Lumbar Microdiscectomy: A Prospective Study

Abstract

Background of the Study: The clinical experience that there is a great variability in the ease of performing lumbar microdiscectomy, in particular while instructing the trainee surgeons. Objective: To determine the role of the pre operative symptoms, it is duration and the radiological findings on influencing the procedure of lumbar microdiscectomy for a single lumbar disc prolapse. Method: A prospective study of 82 patients with a single level lumbar disc prolapse included the analysis and correlation of clinical and radiological factors: age, sex, height, weight, type of physical work, presenting symptoms and their duration, the level and status of the disc prolapse - to the intra-operative findings of epidural vein dilatation, degree of fibrosis, and the duration of operation. The data were subjected to detailed analysis by using the statistical package of Social Science (SPSS/PC) Release 10. Results: Thirty two percent of patients had significantlydilated epidural veins; their presence was influenced by the predominance of low back pain and the duration of symptoms. A third (34%) of patients had appreciable fibrosis at the surgical site, again influenced by low back pain, duration of symptoms and radiological findings of obstruction and bony abnormalities. In 37% of the patients the blood loss was in excess of 100 ml seen in patients with a profile similar to those with significant fibrosis. The procedure of microdiscectomy lasted longer than 120 minutes in 34% of patients whose predominant symptom was low back pain with prolonged duration of symptoms and abnormal x-ray findings. Conclusion: The patient's preoperative clinical presentation and the radiological appearance of the prolapsed disc can affect significantly the microsurgical procedure. The short history of illness with more pronounced leg pain in the absence of bony abnormalities would favor easier operation; while Lumbar microdiscectomy is expected to be a difficult procedure in patients with low back pain as predominant symptom lasting for longer than 12 months and in whom the disc prolapsed is central or who showed additional bony abnormalities.