Correlation between Clinical Features and Findings Observed on Magnetic Resonance Imaging in Patients with Lumbar Disc Prolapse

Background: Lumbar disc prolapse is one of the common causes of low back pain seen in active people. There are different reports regarding the clinical significance of various magnetic resonance imaging (MRI) findings observed in these patients. The study was conducted to correlate the clinical features and MRI abnormalities.

Methodology: This prospective study was carried out in department of Orthopaedics, in tertiary referral centre, for a year. Eighty six clinically diagnosed patients of lumbar disc prolapse were included in the study. They had a complete lumbar spine MRI with 3 tesla scanner. Clinical evaluation included pain distribution, neurological signs and symptoms. The MRI findings were then correlated with clinical signs and symptoms.

Results: This study included 86 patient, mean age 41years ± 8.790, male to female ratio 1.2:1 and 49 patients (57%) were heavy workers. All patients presented with low back pain and radicular leg pain. Straight leg raising test was positive in 82.6% patients. 78 (90.7%) patients had neurological deficit (motor or sensory) and 28 patients had absent ankle reflex. There were 174 disc herniations, most common type being disc protrusion, position being centro-lateral and level being L4-L5 and L5-S1 (74.1%). There was statistically significant correlation between MRI findings of nerve root compression and SLRT (p-value = 0.035), absent ankle reflex (p-value <0.001) and neurological deficit (p-value = 0.019). There was no statistically significant correlation between type of disc herniation and neurological signs (p-value > 0.05). The clinical level at L4-L5 & L5-S1 and MRI level L4-L5 & L5-S1 had statistically significant correlation (p-value <0.001 ).

Conclusion: Straight leg raising test (SLRT), neurological deficit and absent ankle reflex correlates well with nerve root compression visible in MRI; Clinical level and MRI level also correlates significantly. The type of disc herniation does not correlate with the neurological deficit.