Role of mri in the management of low back ache: a prospective study

Background: MRI load of low back ache patients is quite high. Nearly 75% of populations suffer from low backache (LBA) with or without sciatica at some or the other time during adulthood. Majority of these patients, after a clinical diagnosis of Prolapsed intervertebral disc, are referred for an MRI, primarly not only for the confirmation of the diagnosis but also for the patient satisfaction (demand) and medico legal reasons. The study was conducted to understand the significance of MRI findings in the production of LBA with Sciatica and its role in its management. Material and Methods: 130 patients of LBA, with sciatica unilateral 78 (60%), bilateral 40 (37.6%) and without sciatica 12 (9.23 %) diagnosed clinically as prolapsed intervertebral Disc, underwent MRI and were evaluated on a uniform pattern by double blind method. The clinical findings of pain distribution dermatomes, sensory loss, motor loss, deep tendon reflexes, local tenderness and straight leg raising tests (SLR) were recorded. MRI evaluation noted the Grades of Disc Degeneration, Level & Type of prolapse, Neural foramina compromise, root impingement and other miscellaneous findings. All the variables of clinical presentation and MRI findings were compared to find out their significance. Inter and intra observer variations were calculated for significance by Kappa coefficient. Results: MRI levels of disc prolapse, impingement, foramina compromise and disc extrusions correlated well with clinical picture in 109 (83.8%) patients. Disc bulges single or multiple were mostly (88%) asymptomatic. Small impingements with effacement did not correlate with neurological/ dermatome level clinically. There was insignificant inter or intraobserver variation in interpretation of most of the MRI observations (Kappa score 0.56), however a minor intraobserver variation of (Kappa 0.34) was observed in labeling various types of disc prolapses. Conclusions: Not all cases of LBA with or without sciatica are prolapse disc and vice versa. Paracentral protrusion or extrusion with moderate to severe foramina impingement correlate well with clinical presentation whereas, central bulges and small disc protrusions show poor relation to clinical findings. The management of LBA & sciatica should depend upon the severity of pain, its distribution, response to conservative treatment and importance of neurological deficit and MRI help should be sought only in cases not responding to conservative treatment, doubtful diagnosis, important neurological deficit (Bowl Bladder involvement) and in cases where surgery has been planned.