Evaluation of endoscopic dorsal ramus rhizotomy in managing facetogenic chronic low back pain

• Lower VAS scores of pain was achieved after surgery.
• Better outcome with respect to percentage of pain relief was obtained after surgery.
• Higher MacNab scores of 1 year follow-up was achieved after surgery.
• Four newly identified anatomical variations of medial branch anatomy were reported.

ObjectiveTo study the effectiveness of surgical dorsal endoscopic rhizotomy for the treatment of facetogenic chronic low back pain.MethodsFrom April 2011 to November 2011, 58 patients who were diagnosed with lumbar facetogenic chronic low back pain (CLBP) and thereafter experienced >80% reliefs of pain with two comparative lumbar medial branch blocks were recruited in the study. Of those 58 patients, 45 cases (the operation group) received dorsal endoscopic rhizotomy, and the remaining 13 cases (the conservative group) received conservative treatment. Patients’ preoperative and postoperative VAS score, percentage of pain relief and the MacNab score were analyzed and compared. Anatomic variations and any possible complications were recorded.ResultsIn the operation group, VAS scores of pain (low back/referred) at any time point postoperatively were significantly lower than that before MBB (P < 0.05), which, however, showed no significant difference as compared to the scores after MBB (P > 0.05). In the conservative group, VAS scores of pain (low back/referred) at any time point postoperatively with conservative treatment decreased significantly compared with that before MBB (P < 0.05) and were significantly higher than that after MBB (P < 0.05). Percentage of pain relief in the operation group at any time point postoperatively were significantly higher than that in the conservative group (P < 0.01). The MacNab scores of 1 year follow-up in the operation group were higher than that in the conservative group. In addition, four separate newly identified anatomical variations of medial branch anatomy were observed and reported.ConclusionDorsal endoscopic rhizotomy is safe and effective for the facetogenic CLBP, and can achieve better clinical outcome than the conservative treatment.