Address of correspondence: Mumbai Spine Scoliosis and Disc Replacement Centre.Bombay Hospital, Mumbai
Objective:The aim of the present study is to determine influence of body-mass index (BMI) on outcomes of MED for LCS.Background:Many patients undergoing decompression surgery for lumbar canal stenosis(LCS) are overweight. Literature shows relatively poor outcomes and increased peri-operative complications in obese patients undergoing decompression surgery for LCS. However, the relationship between body habitus and outcomes after minimally invasive decompression surgery, popularly known as Micro-Endoscopic Decompression (MED) is not well defined.Materials and Methods:The study period extended from June 2010 to June 2013. All consecutive patients with symptomatic LCS failing conservative management were considered for surgery. The patients were classified as overweight(BMI>25 kg/m²) and normal( BMI < 25 kg/m²) according to international classification of WHO . All patients underwent MED using the 18mm METRX tubular retractor (Medtronics,Memphis,USA). The central canal and the ipsi-lateral and contra-lateral nerve roots were decompressed using “Wanding” technique through a unilateral approach. The outcomes were assessed using pre-operative and post-operative Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) for leg pain and back pain. The operative time, blood loss, the duration of hospital stay and complications were analysed. The results were also analysed in comparison with the literature representing open surgeries for LCS.
In all 65 cases were included in study. Of these 30 (40 %) were obese and 35 (46.6%) were non-obese.The mean preoperative ODI in obese and non obese patient was of 58.76 and 63.54 and mean postoperative ODI was 19 and 18.45 respectively. The improvement rate in ODI score in the obese group (p value<0.05) and in non-obese group (p value<0.05) is almost similar. In the obese group, the mean pre-operative and post-operative VAS score for leg pain was 8 and 0.8 respectively. Similarly in non-obese group, pre-operative and post-operative VAS score for leg pain was 5.6 and 1.14 respectively. In obese group, the mean preoperative and post-operative VAS score of back pain was 5.05 and 1.3 .Similarly in non-obese group, the mean pre-operative and post-operative VAS score for back pain was 3.9 and 1.4 . There was no statistically significant difference in the change of ODI scores (p value<0.05) and VAS scores between these groups irrespective of BMI. The mean operative time in obese group was 127 minute and mean operative time in non-obese group is 111 minute. Average operative blood loss and length of stay was about 75-90 ml and 3-4 days respectively. There were two minor complications in the obese group.
Obese and non-obese patients benefit equally from MED. The overall complication rate in obese patients is minimal in comparison with the non-obese patients. In comparison with the published literature of patients undergoing open surgery for LCS, obese patients achieved better pain reduction, better walking ability, and improved quality of life after MED. This is an advantage over open surgery as we can avoid problems like longer operative time, extensive exposures, increased intra-operative bleeding, poor outcomes and peri-operative complications. The excellent outcomes and incidence of minimal complications is a result of the inherent technique of the MED procedure. The authors strongly recommend this minimally invasive procedure(MED) for LCS, especially in obese patients.
How to Cite this Abstract
Pisal T, Bhute N, Patil V, Kulkarni A. Micro-Endoscopic Decompression for Lumbar Canal Stenosis – A boon for obese patients. International Journal of Conference Proceedings 2015;(2015):60