Preoperative magnetic resonance imaging Abnormalities Predictive of Lumbar Herniation Recurrence following Surgical Repair.

OBJECTIVE: There are currently no standard criteria for evaluating the risk of recurrent disk herniation following surgical repair. This study investigated the predictive values of five presurgical imaging parameters, paraspinal muscle quality, annular tear size, Modic changes, modified Phirrmann disk degeneration grade, and presence of sacralization or fusion.

METHODS: Between 2015 and 2018, 188 patients(89 female, 99 male, median age 50) receiving first corrective surgery for lumbar disk herniation were enrolled. Microdiscectomy was performed in 161 of these patients and endoscopic translaminar discectomy approach was performed in 27 patients.Clinical status was evaluated before surgery and 4, 12, and 24 months postsurgery using a Visual Analog Scale(VAS), Oswestry Disability Index(ODI), and Short Form 36(SF36).

RESULTS: Recurrent disk herniation was observed in 21 of 188 patients. 17 of the recurrences disc herniations were seen in those who underwent microdiscectomy and 4 in those who underwent endoscopic translaminar discectomy. There were significant differences in VAS, ODI, and SF36 scores at 4, 12, and 24 months between patients with recurrence and the 167 no-recurrence patients. The median annular tear length was significantly greater in patients with recurrence than without recurrence. In addition, there were significant differences in recurrence rate according to Modic change type distribution, sacralization or fusion presence, Pfirmann disk degeneration grade distribution, dichotomized annular tear size, dichotomized Modic change type and simplified 3-tier muscle degeneration classification distribution.

CONCLUSIONS: Patients with poor clinical scores and recurrence exhibited additional radiological abnormalities prior to surgery such as poor paraspinal muscle quality, longer annular tears, higher Modic change type, higher modified Phirrmann disk degeneration grade, and sacralization or fusion. This risk evaluation protocol may prove valuable for patient selection, surgical planning, and choice of postoperative recovery regimen.