To conduct a prospective study to assess whether we can predict the presence of hyaline material in the extruded disk from preoperative magnetic resonance imaging (MRI) in patients with lumbar disk herniations and its clinical significance.

Hundred patients posted for microlumbar discectomy were included in the study. They were assessed preoperatively for severity of symptoms using visual analog scale (VAS). Detailed radiological assessment was done using MRI. Following surgery, extruded disk specimens were sent for histopathological examination. The presence of hyaline material in biopsy was correlated with specific MRI findings and postoperative outcome assessed based on the VAS score.

Out of the 100 patients, there were 58 males and 42 females between the age of 18 and 55 years. Histopathology of herniated disk material showed annulus fibrosis in 15% of patients, nucleus pulposus in 78% and a combination of both in 7%. Hyaline cartilage was found in 24% of patients. Extend of Modic changes more than 50% of vertebral end plate in MRI was indicative of the presence of hyaline in biopsy (p < 0.001). Preoperative MRI finding of vertebral end plate defect (VEPD) was associated with the presence of hyaline in 92.8% of cases. Presence of hyaline was correlated with the improvement in mean VAS score postoperatively.

In this study, the importance of hyaline in the extruded disk with its clinical significance is emphasized. We conclude that the presence of hyaline, as predicted from MRI findings like VEPD and extend of Modic changes, is a predictor of good postoperative outcome.

Gopal VV, Mahadevan K. Importance of Hyaline Material in Herniated Lumbar Disk Pathology: Predicting the Presence of Hyaline from Preoperative Magnetic Resonance Imaging and its Clinical Significance. J Spinal Surg 2015;2(2):42-47.