Foraminal and far lateral lumbar disc herniation: outcome of unilateral full facetectomy with instrumented fusion

Abstract

Background Far lateral lumbar disc herniation is a clinical condition characterized by nerve root compression out of the spinal canal, in its extraforaminal/extracanalicular course at the inferior or lateral aspect of the facet joint. Objective To analyze the effect of unilateral full facetectomy with instrumented fusion in management of foraminal and far lateral lumbar disc herniation. Methods This retrospective trial carried out on 34 cases (24 males, 10 females) aged from 27 to 68, with mean value of 49 years who were entered to the Neurosurgery Department, Menoufia University Hospital from January 2018 and January 2022. All patients suffered from foraminal and/or far lateral lumbar disc herniation and were treated with unilateral full facetectomy with instrumented fusion. Results The herniation level was at L2-3, L3-4, L4-5, and L5-S1 in 2, 10, 18, and 4 patients, respectively. Overall, the mean preoperative VAS score decreased from 8.6 to 2.3 in the short-term. When the long-term functional outcome following surgery was analyzed according to the MacNab Criteria, the recovery was excellent, good, fair, and poor in 26, 8, 0, and 0, respectively. Conclusions Full facetectomy ± laminectomy technique provides direct visualization of the complete course of the nerve root extending far laterally to avoid missed disc fragments and protect the nerve root from inadvertent trauma. Pedicle fixation for stabilization following full facetectomy has been indicated to avoid postoperative pain syndromes due to `micro-instability'.