Preoperative HbA1c and Postoperative Outcomes in Spine Surgery: A Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: To perform a systematic review and meta-analysis of previous studies on HbA1c in preoperative risk stratification in patients undergoing spinal procedures and provide an overview of the consensus recommendations. SUMMARY OF BACKGROUND DATA: Diabetes mellitus (DM) and hyperglycemia have been shown to be independent risk factors for increased surgical complications. Glycated Hemoglobin A1C (HbA1c), a surrogate for long term glycemic control, is an important preoperative parameter that may be optimized to reduce surgical complications and improve patient-reported outcomes. However, comprehensive systematic reviews on preoperative HbA1c and postoperative outcomes in spine surgery have been limited. METHODS: We systematically searched PubMed, EMBASE, Scopus, and Web-of-Science for English-language studies from inception through April 5 th , 2022, including references of eligible articles. The search was conducted according to PRISMA guidelines. Only studies in patients undergoing spine surgery with preoperative HbA1c values and postoperative outcomes available were included. RESULTS: A total of 22 articles (18 retrospective cohort studies, 4 prospective observational studies) were identified with level of evidence III or greater. The majority of studies (n=17) found that elevated preoperative HbA1c was associated with inferior outcomes or increased risk of complications. Random-effect meta-analysis demonstrated that patients with preoperative HbA1c >8.0% had increased risk(s) of postoperative complications (RR: 1.85, 95% CI: [1.48, 2.31], P <0.01) and that patients with surgical site infection (SSI) had higher preoperative HbA1c (Mean Difference: 1.49%, 95% CI: [0.11, 2.88], P =0.03). CONCLUSION: The findings of this study suggest that HbA1c >8.0% is associated with an increased risk of complications. HbA1c was higher by 1.49% on average among patients with SSI when compared to patients who did not experience SSI. These results suggest that elevated HbA1c is associated with less favorable outcomes following spine surgery. LEVEL OF EVIDENCE: IV.

Laminectomy With Fusion is Associated With Greater Functional Improvement Compared With Laminectomy Alone for the Treatment of Degenerative Lumbar Spondylolisthesis: A Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic review and Meta-analysis. OBJECTIVE: To compare outcomes and complications profile of laminectomy alone versus laminectomy and fusion for the treatment of degenerative lumbar spondylolisthesis (DLS). SUMMARY OF BACKGROUND DATA: Degenerative lumbar spondylolisthesis is a common cause of back pain and functional impairment. DLS is associated with high monetary (up to $100 billion annually in the US) and nonmonetary societal and personal costs. While nonoperative management remains the first-line treatment for DLS, decompressive laminectomy with or without fusion is indicated for the treatment-resistant disease. METHODS: We systematically searched PubMed and EMBASE for RCTs and cohort studies from inception through April 14, 2022. Data were pooled using random-effects meta-analysis. The risk of bias was assessed using the Joanna Briggs Institute risk of bias tool. We generated odds ratio and standard mean difference estimates for select parameters. RESULTS: A total of 23 manuscripts were included (n=90,996 patients). Complication rates were higher in patients undergoing laminectomy and fusion compared with laminectomy alone (OR: 1.55, P <0.001). Rates of reoperation were similar between both groups (OR: 0.67, P =0.10). Laminectomy with fusion was associated with a longer duration of surgery (Standard Mean Difference: 2.60, P =0.04) and a longer hospital stay (2.16, P =0.01). Compared with laminectomy alone, the extent of functional improvement in pain and disability was superior in the laminectomy and fusion cohort. Laminectomy with fusion had a greater mean change in ODI (-0.38, P <0.01) compared with laminectomy alone. Laminectomy with fusion was associated with a greater mean change in NRS leg score (-0.11, P =0.04) and NRS back score (-0.45, P <0.01). CONCLUSION: Compared with laminectomy alone, laminectomy with fusion is associated with greater postoperative improvement in pain and disability, albeit with a longer duration of surgery and hospital stay.

Bariatric Surgery Before Spine Surgery is Associated With Fewer Postsurgical Complications: A Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: To perform a systematic review and meta-analysis investigating the rate of adverse events after spine surgery in patients who underwent bariatric surgery (BS). SUMMARY OF BACKGROUND DATA: Obesity is an established risk factor for postoperative complications after spine surgery. BS has been associated with improvements in health in patients with severe obesity. However, it is not known whether undergoing BS before spine surgery is associated with reduced adverse outcomes. MATERIALS AND METHODS: PubMed, EMBASE, Scopus, and Web-of-Science were systematically searched according to "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" guidelines. The search included indexed terms and text words from database inception to the date of the search (May 27, 2022). Data and estimates were pooled using the Mantel-Haenszel method for random-effects meta-analysis. Risk of bias was assessed using the Joanna Briggs Institute risk of bias tool. The primary outcome was an all-cause complication rate after surgery. Relative risks for surgical and medical complications were assessed. RESULTS: A total of 4 studies comprising 177,273 patients were included. The pooled analysis demonstrated that the all-cause medical complication rate after spine surgery was lower in patients undergoing BS (relative risk: 0.54, 95% CI: 0.39, 0.74, P < 0.01). There was no difference in rates of surgical complications and 30-day hospital readmission rates between the cohort undergoing BS before spine surgery and the cohort that did not. CONCLUSION: These analyses suggest that obese patients undergoing BS before spine surgery have significantly lower adverse event rates. Future prospective studies are needed to corroborate these findings. LEVEL OF EVIDENCE: 4.

Do Obese Patients Lose Weight After Lumbar Spine Surgery: A Systematic Review and Meta-Analysis.

OBJECTIVE: Obesity is a major health care concern in the United States and is associated with high rates of postoperative complications after spine surgery. Obese patients assert that weight reduction is not possible unless spine surgery first relieves their pain and concomitant immobility. We describe the post-spine surgery effects on patient weight, with an emphasis on obesity. METHODS: PubMed, EMBASE, Scopus, Web of Science, and Cochrane databases were systematically searched according to the PRISMA guidelines. The search included indexed terms and text words from database inception to the date of the search (15 April 2022). Studies chosen for inclusion had to have data reporting on pre- and postoperative patient weight after spine surgery. Data and estimates were pooled using the Mantel-Haenszel method for random-effects meta-analysis. RESULTS: Eight articles encompassing 7 retrospective and 1 prospective cohort were identified. A random effects model analysis demonstrated that overweight and obese patients (body mass index [BMI], >25 kg/m2) had increased odds of clinically significant weight loss after lumbar spine surgery compared with non-obese patients (odds ratio, 1.63; 95% confidence interval, 1.43-1.86, P < 0.0001). There was no significant difference in the raw weight change between BMI categories (mean difference, -0.67 kg, 95% confidence interval, -4.71 to 3.37 kg, P = 0.7463). CONCLUSIONS: Compared with non-obese patients (BMI, <25 kg/m2), overweight and obese patients have higher odds of clinically significant weight loss after lumbar spine surgery. No difference in pre-operative and post-operative weight was found, although statistical power was lacking in this analysis. Randomized controlled trials and additional prospective cohorts are needed to further validate these findings.

Robotic and navigated pedicle screws are safer and more accurate than fluoroscopic freehand screws: a systematic review and meta-analysis.

BACKGROUND CONTEXT: Navigated and robotic pedicle screw placement systems have been developed to improve the accuracy of screw placement. However, the literature comparing the safety and accuracy of robotic and navigated screw placement with fluoroscopic freehand screw placement in thoracolumbar spine surgery has been limited. PURPOSE: To perform a systematic review and meta-analysis of randomized control trials that compared the accuracy and safety profiles of robotic and navigated pedicle screws with fluoroscopic freehand pedicle screws. STUDY DESIGN/SETTING: Systematic review and meta-analysis PATIENT SAMPLE: Only randomized controlled trials comparing robotic-assisted or navigated pedicle screws placement with freehand pedicle screw placement in the thoracolumbar spine were included. OUTCOME MEASURES: Odds ratio (OR) estimates for screw accuracy according to the Gertzbein-Robbins scale and relative risk (RR) for various surgical complications. METHODS: We systematically searched PubMed and EMBASE for English-language studies from inception through April 7, 2022, including references of eligible articles. The search was conducted according to PRISMA guidelines. Two reviewers conducted a full abstraction of all data, and one reviewer verified accuracy. Information was extracted on study design, quality, bias, participants, and risk estimates. Data and estimates were pooled using the Mantel-Haenszel method for random-effects meta-analysis. RESULTS: A total of 14 papers encompassing 12 randomized controlled trials were identified (n=892 patients, 4,046 screws). The pooled analysis demonstrated that robotic and navigated pedicle screw placement techniques were associated with higher odds of screw accuracy (OR 2.66, 95% CI 1.24-5.72, p=.01). Robotic and navigated screw placement was associated with a lower risk of facet joint violations (RR 0.09, 95% CI 0.02-0.38, p<.01) and major complications (RR 0.31, 95% CI 0.11-0.84, p=.02). There were no observed differences between groups in nerve root injury (RR 0.50, 95% CI 0.11-2.30, p=.37), or return to operating room for screw revision (RR 0.28, 95% CI 0.07-1.13, p=.07). CONCLUSIONS: These estimates suggest that robotic and navigated screw placement techniques are associated with higher odds of screw accuracy and superior safety profile compared with fluoroscopic freehand techniques. Additional randomized controlled trials will be needed to further validate these findings.