RESUMO
Far lateral disc herniations account for between 7% and 12% of all disk herniations and occur predominantly at L3/4 and L4/5.1,2 They can cause severe radicular pain due to dorsal root ganglion involvement and are exacerbated by lateral bending to the side of the lesion. Back pain is less of a feature with this pathology.3 The Wiltse approach was first described in the 1960s as an approach to L5/S1 noninstrumented fusion for isthmic spondylolisthesis4; its use in pedicle screws and far lateral discs was described in 1988.5 It has been shown to reduce muscle atrophy, wound infection, and blood loss.6,7 The Wiltse approach for a far lateral disc herniation provides a direct route to the disc pathology and as such is useful in cases with this isolated pathology. It confers less extensive muscle dissection and therefore less postoperative pain, minimal bone resection with preservation of the integrity of the facet joint, and it does not rely on endoscopy (rather the traditional operating microscope). It can also be used where endoscopy is contraindicated such as in revision cases. Here we present the case of a 53-year-old woman who presented with several weeks of back pain and right L3 radiculopathy, as well as right hip flexion and knee extension weakness. A Wiltse approach microdiscectomy was proposed for her far lateral disk herniation, and the patient consented to the procedure. At 6 weeks of follow-up, her radicular pain had resolved and there was improvement in hip flexion and knee extension. Image at 5:50 of Surgical Video is used with permissions from the Wiltse, L, Bateman, JD, Hutchinson, RH, and Nelson, WE. The Paraspinal Sacrospinalis-Splitting Approach to the Lumbar Spine. J Bone Joint Surg Am. 1968;50(5):919-926. Copyright © 1968 by The Journal of Bone and Joint Surgery, Inc.
RESUMO
BACKGROUND: Recombinant human bone morphogenetic protein-2 (rhBMP-2) combined with an activated collagen scaffold (Infuse; Medtronic, MN) has been used to facilitate lumbar intervertebral fusion; however, data regarding its efficacy are inconsistent. We aimed to assess the efficacy of rhBMP-2 when used in posterior lumbar interbody fusion (PLIF) by analyzing the rate of reoperation for nonunion and patient-reported outcome measures in a large retrospective case series. We also aimed to assess the impact of patient and surgical factors on rates of reoperation and determine frequency of complications. METHODS: Prospectively collected data from a single-surgeon database of consecutive PLIFs (minimum 18-month follow-up) were retrospectively analyzed. PLIF was performed with pedicle screw instrumentation, intervertebral spacers, and locally harvested bone graft to which rhBMP-2 and bone marrow aspirate (BMA) were added. Multivariate logistic regression was used to determine the influence of patient and surgical factors on the primary outcome: reoperation for confirmed nonunion. RESULTS: A total of 1019 operations at 1485 levels across 908 patients were analyzed. Mean duration of follow-up was 51.7 ± 30.0 months (range 18-172). Twelve patients required reoperation for nonunion (1.2%). Increasing body mass index was found to be significant in predicting reoperation (OR 1.114, P = 0.046). Postoperative radiculitis was common (42%) but transient in most cases. There were significant and sustained improvements in patient-reported outcome measures postoperatively. Four cases of osteolysis and 5 of epidural cyst were recorded, and a reduction of rhBMP-2 dose seemed to ameliorate these sequelae. CONCLUSION: In this large retrospective observational study, PLIF performed with rhBMP-2 and BMA resulted in a low rate of clinically significant nonunion and significant improvement in patient-reported outcomes. Transient radiculitis was common. Osteolysis and epidural cyst formation were rare and possibly related to dosage. CLINICAL RELEVANCE: rhBMP-2 is effective when used in PLIF, resulting in a high rate of fusion and improved patient outcomes, and it has an acceptable safety profile.