Effect of Smoking Status on Successful Arthrodesis, Clinical Outcome, and Complications After Anterior Lumbar Interbody Fusion (ALIF).

BACKGROUND: Anterior lumbar interbody fusion (ALIF) is a surgical technique indicated for the treatment of several lumbar pathologies. Smoking has been suggested as a possible cause of reduced fusion rates after ALIF, although the literature regarding the impact of smoking status on lumbar spine surgery is not well established. This study aims to assess the impact of perioperative smoking status on the rates of perioperative complications, fusion, and adverse clinical outcomes in patients undergoing ALIF surgery. METHODS: A retrospective analysis was performed on a prospectively maintained database of 137 patients, all of whom underwent ALIF surgery by the same primary spine surgeon. Smoking status was defined by the presence of active smoking in the 2 weeks before the procedure. Outcome measures included fusion rates, surgical complications, Short-Form 12, and Oswestry Disability Index. RESULTS: Patients were separated into nonsmokers (n = 114) and smokers (n = 23). Univariate analysis demonstrated that the percentage of patients with successful fusion differed significantly between the groups (69.6% vs. 85.1%, P = 0.006). Pseudarthrosis rates were shown to be significantly associated with perioperative smoking. Results for other postoperative complications and clinical outcomes were similar for both groups. On multivariate analysis, the rate of failed fusion was significantly greater for smokers than nonsmokers (odds ratio 37.10, P = 0.002). CONCLUSIONS: The rate of successful fusion after ALIF surgery was found to be significantly lower for smokers compared with nonsmokers. No significant association was found between smoking status and other perioperative complications or adverse clinical outcomes.

A novel technique for placement of sacro-alar-iliac (S2AI) screws by K-wire insertion using intraoperative navigation.

Sacral-iliac fixation techniques may be indicated in the management of various lumbosacral pathologies including spinal degeneration, infection, tumour resection, fracture, pseudarthrosis, correction of spinal deformities involving long fusion constructs to the sacrum and cases with poor sacral fixation. There are a number of options for lumbosacral fixation each with their own advantages and disadvantages. Though S2-alar-iliac (S2AI) have demonstrated promising advantages over alternatives, the complex anatomy of the spinopelvic region demands precise insertion of the screws to create a biomechanically robust construct safely. As such, we present a novel technique of using intra-operative CT navigation and K-wires to establish and secure a planned trajectory, thereby ensuring solid spinopelvic fixation with S2AI screws. This was performed as part of a long fusion construct for correction of kyphosis deformity in a male patient.

Subsidence following anterior lumbar interbody fusion (ALIF): a prospective study.

BACKGROUND: Anterior lumbar interbody fusion (ALIF) is a widely used surgical technique for disorders of the lumbar spine. One potential complication is the subsidence of disc height in the post-operative period. Few studies have reported the rate of subsidence in ALIF surgery prospectively. We prospectively evaluated the rate of subsidence in adult patients undergoing ALIF. METHODS: Results were obtained by reviewing scans of 147 patients. Disc heights were measured on radiographic scans taken pre-operatively in addition to post-operatively immediately, at 6 weeks and at 18 months. The anterior and posterior intervertebral disc heights were measured. Subsidence was defined as greater than or equal to 2 mm loss of height. RESULTS: A total of 15 patients (10.2%) had subsidence, with 7 being male. Each case was of delayed cage subsidence (DCS) >6 weeks postoperatively. The mean subsidence was 4.7 mm (range, 2.4-7.8). Mean anterior disc height was 8.6±0.4 mm preoperatively, which improved to 15.1±0.5 mm at latest follow-up. Mean posterior disc height was 4.7±0.2 mm preoperatively, which improved to 8.7±0.4 mm at latest follow-up. The mean lumbar lordosis (LL) angle was 42.5°±10.8° and the mean local disc angle (LDA) was 6.7°±4.0°. The 91.2% (n=114/125) of patients with appropriate radiological follow-up demonstrated fusion by latest follow-up. There was no correlation between subsidence rate with patient reported outcomes [Visual Analog Scale (VAS), Oswestry Disability Index (ODI) and Short Form 12 Item survey (SF-12)] and fusion rates. There was a significant negative correlation between LL and extent of subsidence (Pearson correlation =-0.754, P=0.012). CONCLUSIONS: In conclusion, we found that the subsidence rate at follow-up was generally low following standalone ALIF for this patient series. Patient clinical outcomes and bony fusion rates were not significantly influenced by subsidence.

Evaluating Outcomes of Stand-Alone Anterior Lumbar Interbody Fusion: A Systematic Review.

BACKGROUND: Stand-alone anterior lumbar interbody fusion (ALIF) is an effective surgical approach for selected spinal pathologies. It avoids the morbidity and complications associated with instrumented ALIF, such as plate fixation and the traditionally used posterior approach. Despite improved disc space visualization and clearance, the associated posterior instability and increased risk of nonfusion present major challenges to this approach. The integral cage design aims to address these challenges by providing the necessary stabilization through intracorporeal screws. However, there is limited and controversial data available for stand-alone ALIF and integral cage fixation. To our knowledge, this is the first systematic review to evaluate recent findings on outcomes of stand-alone ALIF devices to explore areas of controversy and identify directions for future research. METHODS: Two reviewers conducted independent, systematic literature searches for appropriate studies in 5 electronic databases as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies were filtered by the use of specified selection criteria, particularly exclusion of studies with supplementary fixation to ALIF and studies published before the year 2000. A total of 17 studies met the criteria, and their data were comprehensively extracted and analyzed. RESULTS: The current literature is supportive of stand-alone ALIF due to acceptable clinical outcomes, promising fusion rates and disc height restoration. However, data and outcomes remain preliminary, and there are numerous areas of controversy. CONCLUSIONS: There is evidence for the efficacy and safety of stand-alone ALIF. However, the extent of improvement based on specific indications for surgery remains unclear. Further investigation utilizing more methodologically rigorous studies of long-term outcomes is necessary to address these issues.