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Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction in patients older than age 55, with operative management being a widely adopted approach. Previous work has shown that private insurance status, gender and patient race are predictive of the operative approach patients receive (anterior-only, posterior-only, combined anterior-posterior). The Nationwide Inpatient Sample from 2001 to 2010 was used to assess the potential role of multilevel CSM as a contributing factor in determining which operative approach CSM patients receive, as it is rare for an anterior-only approach to be sufficient for CSM patients requiring fusion of four or more involved levels. Multivariate analyses revealed that female sex (OR=3.78; 95% CI=2.08-6.89; p<0.0001), private insurance (OR=5.02; 95% CI=2.26-11.12; p<0.0001), and elective admission type (OR=4.12; 95% CI=1.65-10.32; p=0.0025) were predictive of increased receipt of a 3+ level fusion in CSM. No other variables, including patient age, race, income, or admission source were predictive of either increased or decreased likelihood of receiving fusion of at least three levels for CSM. In conclusion, female sex, private insurance status, and elective admission type are each independent predictors in CSM for receipt of a 3+ level fusion, while patient age, race and income are not. Given the propensity of fusions greater than three levels to require posterior approaches and the association between posterior CSM approaches and increased morbidity/mortality, these findings may prove useful as to which patient demographics are predictive of increased morbidity and mortality in operative treatment of CSM.

INTRODUCTION: Posterior C1-C2 fusion is a highly successful treatment for atlantoaxial instability and other pathologies of the cervical spine, with fusion rates approaching 95%-100%. However, poor visualization of the lateral masses of C1 secondary to the course of the C2 nerve root along with blood loss from the venous plexus and compression of the C2 nerve from lateral mass screws are technical obstacles that can arise during surgery. Thus, sacrifice of the C2 nerve root has long since been debated in fusions involving the C1 and C2 vertebral bodies. METHODS: Cadaveric dissections on four adult specimens were performed. Both intradural and extradural courses of C2 were studied in detail. The tentative site of C2 nerve root compression during placement of C1 lateral mass screws was studied in detail. Both the indication as well as the ease of C2 neurectomy were studied in relation to postoperative compression and entrapment. RESULTS: Four-six dorsal rootlets of C2 nerve were observed while studying the intradural course. The extradural course was studied with respect to the lateral mass of C1. The greater occipital nerve (GON) course was fairly consistent in all specimens. Transection of C2 around its ganglion would allow for proper C1 lateral mass screw placement as the course of C2 nerve interferes with proper placement of instrumentation. CONCLUSION: C2 nerve root transection is associated with occipital numbness but this often has no effect on health-related quality of life (HRQOL). The C2 nerve root preservation is often associated with entrapment neuropathy or occipital neuralgia, which greatly affects HRQOL. The C2 nerve root transection helps in better visualization, aids in optimal placement of C1 lateral mass screws, minimizes estimated blood loss and improves surgical outcome with successful fusion.

STUDY DESIGN: Retrospective cohort study OBJECTIVE.: To assess factors potentially impacting the operative approach chosen for CSM patients on a nationwide level. SUMMARY OF BACKGROUND DATA: Cervical spondylotic myelopathy (CSM) is one of the most common spinal disorders treated by spine surgeons, with operative management consisting of three approaches: anterior-only, posterior-only, or combined anterior-posterior. It is unknown whether the operative approach used differs based on patient demographics and/or insurance status. METHODS: The Nationwide Inpatient Sample from 2001-2010 was used for analysis. Admissions having a diagnosis code of 721.1 and a primary procedure code of 81.02/81.03, 81.32/81.33, 81.02/81.03 or 81.32/81.33 (combined anterior and posterior fusion/refusion at C2 or below), and 3.09 (decompression of the spinal canal including laminoplasty) were included. Analysis was adjusted for several variables including patient age, race, sex, primary payer for care, and admission source/type. RESULTS: Multivariate analyses revealed that non-Caucasian race [Black (OR = 1.39;95%CI = 1.32-1.47;p < 0.0001), Hispanic (OR = 1.51;95%CI = 1.38-1.66;p < 0.0001), Asian/Pacific Islander (OR = 1.40;95%CI = 1.15-1.70;p = 0.0007), Native American (OR = 1.33;95%CI = 1.02-1.73;p = 0.037)] and increasing age (OR = 1.03; p < 0.0001) were predictive of receiving posterior-only approaches. Female sex (OR = 1.39;95%CI = 1.34-1.43;p < 0.0001), private insurance (OR = 1.19;95%CI = 1.14-1.25;p < 0.0001), and non-trauma center admission type (OR = 1.29-1.39;95%CI = 1.16-1.56;p < 0.0001) were independently predictive of increased likelihood of receiving an anterior-only approach. Hispanic race (OR = 1.35;95%CI = 1.14-1.59;p = 0.0004) and admission source [another hospital (OR = 1.65;95%CI = 1.20-2.27;p = 0.0023), other health facility (OR = 1.68;95%CI = 1.13-2.51;p = 0.011)] were the only variables predictive of increased combined anterior-posterior approaches; Native American race (OR = 0.32;95%CI = 0.13-0.78;p = 0.013) decreased the likelihood of a combined anterior-posterior approach. CONCLUSIONS: Private insurance status, female sex, and Caucasian race independently predict receipt of anterior-only CSM approaches, while non-Caucasian race (Black, Hispanic, Asian/Pacific Islander, Native American) and non-private insurance predict receiving posterior-only CSM approaches. Given recent literature demonstrating posterior-only approaches as predictive of increased mortality in CSM (Kaye et al., 2015), our findings indicate that for CSM patients, non-Caucasian race may significantly increase mortality risk, while private insurance status may significantly decrease the risk of mortality. Further prospective study will be needed to more definitively address these issues. LEVEL OF EVIDENCE: 3.

BACKGROUND CONTEXT: For C1-C2 (atlantoaxial) instability and other pathologies of axial spine, posterior C1-C2 instrumentation is a feasible approach with highly successful rate of cervical spine fusion. With technical expertise, the fusion rates approach 95%-100%. Nevertheless, poor visualization of lateral mass of C1 due to C2 nerve root and/or C2 ganglia, blood loss from venous plexus around vertebral artery and compression of C2 nerve from lateral mass screw are technical issues during posterior C1-C2 instrumentation. PURPOSE: Typically, these patients present with hypo or hyperesthesia in the distribution of C2 nerve referred to as greater occipital neuralgia. Even in adept surgical hands, the rates of C2 nerve dysfunction after posterior C1-2 fusions vary from 4-33%. We studied the usefulness and consequences of sacrificing the C2 nerve root and/or ganglion during C1-C2 instrumentation. STUDY DESIGN/SETTING: meta-analysis. PATIENT SAMPLE: not defined. OUTCOME MEASURES: The feasibility of C2 neurectomy was studied during posterior C1-C2 instrumentation and fusion. Estimated blood loss, operative time, postoperative hyperesthesia or hypoesthesia were also studied during the procedure. METHODS:We did MEDLINE literature search using keywords "C2 neurectomy" or "C2 ganglionectomy" or "C2 neurectomy during atlantoaxial instrumented fusion." We described our technique of sacrificing C2 nerve root and ganglion for posterior C1-C2 instrumentation and fusion. RESULTS: An extensive literature search and our experience conclude the feasibility of C2 neurectomy during placement of C1 lateral mass screws. However, in the absence of C2 neurectomy, postoperative occipital neuralgia significantly affects the functional outcome and quality of life in these patients. Complications were studied after C2 ganglionectomy and neurectomy in these patients. CONCLUSIONS: Neurectomy and/or ganglionectomy offer a reasonably safe dissection to avoid neural and vascular injury in C1-C2 disc space. It serves as an acceptable part of the operation in posterior C1-C2 instrumentation, in frail elderly or redoes procedures. Postoperative hypo or hyperesthesia could be associated with the procedure but it offers a complete relief from intractable C2 neuropathic pain. C2 neurectomy or ganglionectomy is associated with decrease blood loss and operative time

BACKGROUND: Surgical-site infections (SSIs) are a major cause of morbidity and mortality, increasing the length and cost of hospitalization. In patients undergoing spine surgery, there is limited large-scale data on patient-specific risk factors for SSIs. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was reviewed for all spinal operations between 2006 and 2012. The rates of 30 day surgical site infections were calculated, and univariate analysis of selected preoperative risk factors was performed. Multivariate analysis was then used to identify independent predictors of SSIs. RESULTS: 1110 of the 60179 patients (1.84%) had a postoperative wound infection. There were 527 (0.87%) deep and 590 (0.98%) superficial infections. Patients with infections had greater rates of sepsis, longer lengths of stay and more return visits to the operating room. Independent predictors of infection were female gender, inpatient status, insulin dependent diabetes, preoperative steroid use greater than 10 days, hematocrit less than 35, body mass index (BMI) greater than 30, wound class, ASA class, and operative duration. CONCLUSIONS: Analysis of a large national patient database revealed many independent risk factors for SSIs after spinal surgery. Some of these risk factors can be modified preoperatively to reduce the risk of postoperative infection.