Ehlers-Danlos Syndrome is Associated with Increased Rates of Adjacent Segment Disease Following TLIF: A Propensity Matched Study.

BACKGROUND: Ehlers-Danlos syndrome (EDS) is a collection of connective tissue disorders which are often associated with tissue laxity and disc degeneration. However, the implications of EDS on the risk of adjacent segment disease (ASD) after transforaminal lumbar interbody fusion (TLIF) are not well described. The objective of this study is to compare the rates of ASD among patients with EDS and those without EDS. METHODS: Patients who underwent 1-3 level TLIF for degenerative disc disease between 2010-2022 were identified using the PearlDiver Mariner all-claims insurance database. Patients with all types of EDS were included. Patients undergoing surgery for tumors, trauma, or infection were excluded. 1:1 propensity matching was performed using demographic factors, medical comorbidities, and surgical factors which were significantly associated with ASD in a linear regression model. The primary outcome measure was the development of ASD. The secondary outcomes were the development of pseudoarthrosis, medical complications, and surgical complications. RESULTS: Propensity matching resulted in 2 equal groups of 85 patients who did or did not have EDS and underwent 1-3 level TLIF. Patients without EDS were less likely to experience ASD (RR 0.18, 95% CI 0.09-0.35, P < 0.001). There was no significant difference between the 2 patient groups with regards to a diagnosis of pseudoarthrosis, and there was no significant difference for all-cause medical and surgical complications between the 2 patient groups. CONCLUSIONS: After propensity matching to control for confounding variables, the findings of this study suggest that EDS may be associated with an increased risk of ASD following TLIF. Future studies are needed to corroborate these findings.

Synthetic Interbody Devices and Traditional Bone Graft Are Associated With a Similar Rate of Surgical Complications After 1-2 Level Anterior Cervical Discectomy and Fusions.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To compare the rates of all-cause surgical complications of synthetic interbody devices versus allograft or autograft in patients undergoing 1-2 levels anterior cervical discectomy and fusion (ACDF) procedures. SUMMARY OF BACKGROUND DATA: Cervical degenerative disorders affect up to 60% of older adults in the United States. Both traditional allograft or autograft and synthetic interbody devices (polyetheretherketone or titanium) are used for decompression and arthrodesis, with increasing utilization of the latter. However, the differences in their postsurgical complication profiles are not well-characterized. PATIENTS AND METHODS: Patients who underwent 1-2 level ACDFs for cervical radiculopathy or myelopathy between 2010 and 2022 were identified using the PearlDiver Mariner all-claims insurance database. Patients undergoing surgery for nondegenerative pathologies, such as tumors, trauma, or infection, were excluded. 1:1 exact matching was performed based on factors that were significant predictors of all-cause surgical complications in a linear regression model. The primary outcome measure was the development of all-cause surgical complications after 1-2 level ACDFs. The secondary outcome was all-cause medical complications. RESULTS: 1:1 exact matching resulted in two equal groups of 11,430 patients who received treatment with synthetic interbody devices or allograft/autograft. No statistically significant difference in all-cause surgical complications was found between the synthetic cohort and the allograft or autograft cohort after 1-2 level ACDFs (Relative Risk: 0.86, 95% confidence interval: 0.730-1.014, P = 0.079). No significant differences were observed regarding any specific surgical complications except for pseudoarthrosis (Relative Risk: 0.73, 95% confidence interval: 0.554-0.974, P = 0.037), which was higher in the allograft/autograft cohort. CONCLUSION: After 1:1 exact matching to control for confounding variables, the findings of this study suggest that all-cause surgical complications are similar in patients undergoing ACDFs with synthetic interbody devices or allograft/autographs. However, the rate of pseudarthrosis appears to be higher in patients with allograft/autographs. Future prospective studies are needed to corroborate these findings.

Correlation Between Rod Fracture and Shear Stress: A Novel Parameter.

BACKGROUND: We sought to assess the accuracy of a novel parameter proportional to the rod shear stress (RSS) in identifying patients at risk of rod fracture (RF) after surgery for correction of adult spinal deformity. METHODS: We performed a retrospective medical record review of patients aged ≥18 years treated for adult spinal deformity between 2004 and 2014 with ≥24 months of follow-up. The primary outcome was RFs identified radiographically. Patient weight (w), number of instrumented levels (N), and minimum rod diameter (d) were recorded and used to calculate the RSS parameter (RSS=Nwd2). Receiver operating characteristic curves were produced and the area under the curve (AUC ± 95% confidence interval [CI]) was calculated to compare this parameter's discriminative accuracy to that of its constituent variables. The sensitivity, specificity, and likelihood ratios (LRs) were calculated. RESULTS: A total of 28 RF-positive and 154 RF-negative patients were included. The average age was 59.2 ± 9.6 years, and 93.4% were women. The RSS parameter produced the greatest AUC (0.73 ± 0.11). At an RSS cutoff of 30.1, it achieved a sensitivity of 71.4% and specificity of 71.4% (LR, 2.5; 95% CI, 1.8-3.5). The number of instrumented levels produced the next-greatest AUC (0.65 ± 0.12), with a sensitivity of 78.6% and specificity of 50.0% at a cutoff of 15 (LR, 1.6; 95% CI, 1.2-2.0). CONCLUSIONS: The RSS is calculated using easily obtainable information and shows potential as a tool for predicting patient-specific risk of RF after spinal fusion. The number of instrumented levels also correlates strongly with the occurrence of RFs and is not significantly less accurate than the RSS. A larger sample size and prospective validation would be useful in determining with greater confidence which parameter is superior for predicting RFs after spinal fusion.

Cannabis Use is Associated With Higher Rates of Pseudarthrosis Following TLIF: A Multi-Institutional Matched-Cohort Study.

STUDY DESIGN: This was a retrospective cohort study. OBJECTIVE: To compare the rates of pseudarthrosis in patients undergoing 1 to 3 level transforaminal lumbar interbody fusion (TLIF) procedures between cannabis users and noncannabis users. SUMMARY OF BACKGROUND DATA: Recreational use of cannabis is common, though it remains poorly studied and legally ambiguous in the United States. Patients with back pain may turn to adjunctive use of cannabis to manage their pain. However, the implications of cannabis use on the achievement of bony fusion are not well-characterized. METHODS: Patients who underwent 1 to 3 level TLIF for degenerative disc disease or degenerative spondylolisthesis between 2010 and 2022 were identified using the PearlDiver Mariner all-claims insurance database. Cannabis users were identified with ICD 10 code F12.90. Patients undergoing surgery for nondegenerative pathologies such as tumors, trauma, or infection were excluded. 1:1 exact matching was performed using demographic factors, medical comorbidities, and surgical factors which were significantly associated with pseudarthrosis in a linear regression model. The primary outcome measure was development of pseudarthrosis within 24 months after 1 to 3 level TLIF. The secondary outcomes were the development of all-cause surgical complications as well as all-cause medical complications. RESULTS: A 1:1 exact matching resulted in two equal groups of 1593 patients who did or did not use cannabis and underwent 1 to 3 level TLIF. Patients who used cannabis were 80% more likely to experience pseudarthrosis compared with patients who do not [relative risk (RR): 1.816, 95% CI: 1.291-2.556, P <0.001]. Similarly, cannabis use was associated with significantly higher rates of all-cause surgical complications (RR: 2.350, 95% CI: 1.399-3.947, P =0.001) and all-cause medical complications (RR: 1.934, 95% CI: 1.516-2.467, P <0.001). CONCLUSION: After 1:1 exact matching to control for confounding variables, the findings of this study suggest that cannabis use is associated with higher rates of pseudarthrosis, as well as higher rates of all-cause surgical and all-cause medical complications. Further studies are needed to corroborate our findings.

Surgeon Experience Matters: An Exact Matched Analysis of TLIF Outcomes Demonstrates No Difference in Surgical Outcomes Between Experienced Neurosurgeons and Orthopedic Surgeons.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To compare surgical and medical complications profile between neurosurgeons and orthopedic surgeons after transforaminal lumbar interbody fusion (TLIF) procedures. BACKGROUND: Studies comparing the impact of spine surgeon specialty (neurosurgery vs. orthopedic spine) on TLIF outcomes have been inconclusive and failed to control for operative learning curves and surgical maturity. Orthopedic spine surgeons perform fewer spine procedures in residency, although these differences may be attenuated by mandatory fellowship before starting practice. Any observed differences are likely attenuated with increasing surgeon experience. MATERIALS AND METHODS: Using an all-payer claims database, PearlDiver Mariner, 120 million patient records were analyzed between 2010 and 2022, to identify individuals with lumbar stenosis or spondylolisthesis who underwent index one- to three-level TLIF procedures. International Classification of Diseases-Ninth Edition (ICD-9), International Classification of Diseases-10th Edition (ICD-10) and Current Procedural Terminology (CPT) codes were used to query the database. Only Neurosurgeons and Orthopedic spine surgeons who had performed at least 250 procedures were included in the study. Patients undergoing surgery for tumor, trauma, or infection were excluded. 1:1 exact matching was performed using demographic factors, medical comorbidities, and surgical factors which were significantly associated with all-cause surgical or medical complications in a linear regression model. RESULTS: 1:1 exact matching created two equal groups of 18,195 patients without baseline differences who underwent TLIF procedures by neurosurgeons or orthopedic surgeons. There was no difference in all-cause surgical complications between neurosurgeons and orthopedic spine surgeons (relative risk=1.008, 95% CI: 0.850-1.195, P =0.965). All-cause medical complication rate was higher in the neurosurgery cohort (relative risk=1.144, 95% CI: 1.042-1.258, P =0.005). CONCLUSION: The results of this study suggest that after accounting for surgical maturity, neurosurgeons and orthopedic spine surgeons have similar surgical outcomes. However, neurosurgeons have higher all-cause medical complication rates compared with orthopedic spine surgeons. Further research is warranted to validate this relationship in other spine procedures and for other outcomes.

No Difference in Surgical Outcomes between Stand-Alone Devices and Anterior Plating for 1-2 level Anterior Cervical Discectomy and Fusion: A 1:1 Exact Matched Analysis.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: Compare rates of all-cause surgical and medical complications between zero-profile (stand-alone) implants versus any graft type with anterior plate in patients undergoing 1-2 level anterior cervical discectomy and fusion (ACDF) for treatment of degenerative cervical myeloradiculopathy. SUMMARY OF BACKGROUND DATA: Degenerative cervical myeloradiculopathy is increasingly prevalent in older adults. ACDF is a common surgical procedure for decompression of neural structures and stabilization and has been shown to have excellent outcomes. While ACDFs performed with a graft and plate has been the gold standard, more recently, zero-profile implants were developed to decrease implant related complications, such as severe postoperative dysphagia. However, there is a paucity of papers comparing the surgical and medical complications profile of zero-profile (stand-alone) implants to grafts with plating systems. METHODS: Data was extracted from the PearlDiver Mariner Database using CPT codes to classify patients into 1-level, 2-levels, and total 1-2 level ACDFs. Patients undergoing surgery for non-degenerative pathologies such as tumors, trauma, or infection were excluded. RESULTS: 1:1 exact matching created two equal groups of 7,284 patients that underwent 1-2 level ACDF with either grafting with a plate or zero-profile (standalone) implant. There were no statistically significant difference in all-cause surgical complications, pseudarthrosis rate, dysphagia or need for revision surgery between both cohorts (RR 0.99, 95% CI 0.80-1.21, P = 0.95). Additionally, all-cause medical complications were similar between both cohorts (RR 1.07, 95% CI 0.862-1.330, P = 0.573) or any specific surgical or medical complication included in this study. CONCLUSION: After 1:1 exact matching, the results of this study suggest that zero-profile (stand-alone) implants have similar outcomes compared to grafts with plating systems, with no observed differences in all-cause surgical or medical complications profile.

TLIF is Associated With Lower Rates of Adjacent Segment Disease and Complications Compared to ALIF: A Matched-Cohort Analysis.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To compare the rate of adjacent segment disease (ASD) in patients undergoing anterior lumbar interbody fusion (ALIF) versus transforaminal lumbar interbody fusion (TLIF) for the treatment of degenerative stenosis and spondylolisthesis. SUMMARY OF BACKGROUND DATA: ALIF and TLIF are frequently used to treat Lumbar stenosis and spondylolisthesis. While both approaches have distinct advantages, it is unclear whether there are any differences in rates of ASD and postoperative complications. METHODS: A retrospective cohort study of patients who underwent index 1-3 levels ALIF or TLIF between 2010 and 2022, using the PearlDiver Mariner Database, an all-claims insurance database (120 million patients). Patients with a history of prior lumbar surgery and those undergoing surgery for cancer, trauma, or infection were excluded. Exact 1:1 matching was performed using demographic factors, medical comorbidities, and surgical factors found to be significantly associated with ASD in a linear regression model. The primary outcome was a new diagnosis of ASD within 36 months of index surgery, and secondary outcomes were all-cause medical and surgical complications. RESULTS: Exact 1:1 matching resulted in 2 equal groups of 106,451 patients undergoing TLIF and ALIF. The TLIF approach was associated with a lower risk of ASD (RR 0.58, 95% CI 0.56-0.59, P < 0.001) and all-cause medical complications (RR 0.94, 95% CI 0.91-0.98, P =0.002). All-cause surgical complications were not significantly different between both groups. CONCLUSION: After 1:1 exact matching to control for confounding variables, this study suggests that for patients with symptomatic degenerative stenosis and spondylolisthesis, a TLIF procedure (compared to ALIF) is associated with a decreased risk of developing ASD within 36 months of index surgery. Future prospective studies are needed to corroborate these findings. LEVEL OF EVIDENCE: Level-3.