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Background Context: Proximal junctional failure (PFJ) is a common and dreaded complication of adult spinal deformity. Previous research has identified parameters associated with the development of PJF and the search for radiographic and clinical variables continues in an effort to decrease the incidence of PFJ. The lordosis distribution index (LDI) is a parameter not based on pelvic incidence. Ideal values for LDI have been established in prior literature with demonstrated association with PJF.Purpose: The purpose of this study is compare PJF and mechanical failure rates between patients with ideal and nonideal LDI cohort.Study Design: This is a retrospective, single-center case-controlled study.Patient Sample: Adult patients who underwent surgical treatment for spinal deformity as defined by the SRS-Schwab criteria between 2001 and 2016 were included. Furthermore, fusion constructs spanned at least four vertebral segments with the upper instrumented vertebra (UIV) T9 or caudal. Patients who were under the age of 18, those with radiographic data less than 1 year, and those with neoplastic or trauma etiologies were excluded. Prior thoracolumbar spine surgery was not an exclusion criterion.Outcome Measures: The outcome measures were physiologic in nature: The primary outcome was defined as PFJ. The International Spine Study Group (ISSG) definition for PJF was used, which includes postoperative fracture of the UIV or UIV+1, instrumentation failure at UIV, PJA increase greater than 15° from preoperative baseline or extension of the construct needed within 6 months. Secondary outcomes included extension of the construct after 6 months or revision due to instrumentation failure, pseudarthrosis or distal junctional failure.Methods: A portion of this project was funded through National Institute of Health Grant 5UL1TR001067-05. The authors have no conflict of interest related to this study. The records of patients meeting the inclusion criteria were reviewed. Clinical and radiographic data were extracted and analyzed. Univariate cox proportional hazard models were used to identify factors associated with mechanical failure and included in a multivariate Cox proportional hazards model.Results: There were 187 patients that met the inclusion criteria. Univariate analysis demonstrated the number of levels fused, instrumentation to the sacrum or pelvis, PI-LL difference between pre- and postoperative states, T1-SPI, T9-SPI, and postoperative LDI (treated as a continuous variable). When LDI was treated as a categorical variable using an LDI cutoff of less than 0.5 for hypolordotic, 0.5 to 0.8 for aligned and greater than 0.8 for hyperlordotic, there was no difference in failure rates between the two groups.Conclusions: Lumbar lordosis is an important parameter in adult deformity. However, the LDI is an imperfect variable and previously developed categories did not show differences in failure rates in this cohort. [ABSTRACT FROM AUTHOR]

Study Design: Clinical case series.Objective: To investigate the efficacy of intraoperative neuromonitoring in pediatric cervical spine surgery.Summary Of Background Data: Intraoperative neuromonitoring (IONM) consisting of somatosensory-evoked potentials (SSEP) and transcranial motor-evoked potentials (tcMEP) has been shown to effectively prevent permaneny neurologic injury in deformity surgery. The role of IONM during pediatric cervical spine surgery is not well documented. Advances in cervical spine instrumentation have expanded the surgical options in pediatric populations. The goal of this study is to report the ability of IONM to detect neurologic injury during pediatric cervical spine instrumentation.Methods: A single institution database was queried for pediatric-aged patients who underwent cervical spine instrumentation and fusion between 2011 and 2014. Age, diagnosis, surgical indication, number of instrumented levels, and a complete IONM were extracted. Sensitivity and specificity for the detection of neurologic deficits were calculated with exact 95% confidence intervals. Positive and negative predictive values were calculated with estimated 95% confidence intervals.Results: Sixty-seven patients who underwent cervical spine instrumentation were identified with a mean age of 11.6 years (range 1-18). Diagnoses included instability (27), congenital (11), kyphosis (8), fracture (7), tumor (7), arthritis (4), and basilar invagination (3). Mean number of vertebral levels fused was 4 (range 2-7). All patients underwent cervical instrumentation with SSEP and tcMEP monitoring. A significant change in tcMEP monitoring was observed in 7 subjects (10%). There were no corresponding SSEP changes in these patients. The sensitivity of combined IONM was 75% [95% CI = 24.9, 98.7] and the specificity was 98.5% [92.7, 99.9].Conclusion: tcMEP is a more sensitive indicator to spinal cord injury than SSEP, which is consistent with previous studies. IONM changes in 10% of a patient population are significant enough to warrant intraoperative determination if true SCI has occurred or is underway and intervene accordingly.Level Of Evidence: 4. [ABSTRACT FROM AUTHOR]

The opioid epidemic is a public health crisis causing significant morbidity, mortality and economic costs nationwide. As a result, discovering alternative forms of pain management is becoming imperative. Medical marijuana is an option for a nonopioid analgesic and is under investigation for potential uses in fields such as oncology and chronic pain, but it is yet to be studied in the surgical setting. Specifically, its effects on bone healing are not fully understood, significantly affecting its potential analgesic efficacy for postorthopaedic surgical care. The goal of this this study is to determine the effect of cannabis derivatives, D9-tetrahydrocannabinol (THC) and cannabidiol (CBD) on bone healing. The effects of marijuana on spinal arthrodesis specifically have yet to be investigated. We hypothesized that THC and CBD will not decrease bone healing in a rat model for spinal fusion. A basic science study utilizing a validated experimental model to assess spinal fusion performed on rats. N/A (Sprague-Dawley rats were used for this basic science study). Manual palpation was done to assess strength of the L4-L5 arthrodesis on all rats. Twelve rats underwent lumbar three-dimensional micro-computed tomography (μCT) imaging and histological analysis. The remaining half were subjected to quantitative polymerase chain reaction (qPCR) analyses which are currently pending. The μCT bone analysis was comprised of quantifying the ratio of bone volume (BV) to total volume (TV) within each volume of interest (VOI), as well as bone mineral density (BMD) and tissue mineral density (TMD) for the corresponding VOI. During follow-up, one animal from the saline and one from the combination group were lost due to wound dehiscence. Kruskal-Wallis test followed by Dunn's multiple comparisons test was performed using GraphPad Prism. Two-tailed values of p < 0.05 were considered statistically significant. Animal procedures were approved by the Institutional Animal Care and Use Committee (IACUC). Twenty-eight adult Sprague-Dawley rats were used for this study. Utilizing allogenic bone graft (4 donor rats), posterolateral inter-transverse lumbar fusion at the L4-L5 level was performed under surgical microscopy. The animals were divided into four groups of 6, each receiving 0.1ml intraperitoneal injections weekly as follows: placebo (saline), 5 mg/kg THC, 5 mg/kg CBD, and a combination of 5 mg/kg THC and 5 mg/kg CBD (combo). Eight weeks postsurgery, animals were euthanized and fusions were assessed. The combination treatment group had the highest fusion rates, with 66.7% demonstrating full fusion and 33.3% demonstrating partial fusion. This was followed by the THC group demonstrating 60% of rats with full fusion, 20% with partial fusion, and 20% with no fusion. Fusion rates were lower in the CBD and saline groups. However, the fusion rates were not significantly different between the treatment groups based on our manual palpation scoring. Callus formation was visually more extensive in THC and Combo treatments on μCT 3D reconstruction images. This observation was confirmed though μCT data, in which bone volume fraction (BV/TV) was significantly higher for the CBD and THC treatment groups compared to the saline treatment group (P <0.05). BMD and TMD values were higher for all cannabis treatment groups compared to the saline treatment group, though not statistically significant. This study preliminarily demonstrates that CBD and THC have no adverse effect on bone regeneration and rate of spinal fusion in rats. Cannabinoids may possess osteoinductive properties which require further investigation. Future larger animal studies should further investigate the effects of cannabinoid receptor agonists on bone healing and formation, with additional exploration of cannabinoid receptor agonists as a potential alternative approach to postoperative analgesia following spinal fusion and other procedures requiring bone formation. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]

Background Content: Cervical laminoplasty (LP) and laminectomy and fusion (LF) are commonly used surgical techniques for cervical spondylotic myelopathy (CSM). Several recent studies have demonstrated superior perioperative metrics and decreased overall costs with LP, yet LF is performed far more often in the United States.Purpose: To determine the percentage of patients with CSM who are radiographically candidates for LP.Study Design: Retrospective comparative cohort study.Patient Sample: Patients >18 years old who underwent LF or LP for CSM at 2 large academic institutions from 2017 to 2019.Outcome Measures: Candidacy for LP based on radiographic criteria.Methods: Radiographs were assessed by 2 spine surgeons not involved in the care of the patients to determine the C2-C7 Cobb angle and the presence and extent of cervical instability. Patients with kyphosis >13°, > 3.5 mm of listhesis on static imaging, or > 2.5 mm of motion on flexion-extension or standing-supine films were not considered candidates for LP. Intraclass coefficient (ICC) was calculated to assess the interobserver reliability of angular measurements and the presence of instability. The percentage of patients for whom LP was contraindicated was calculated.Results: One hundred eight patients underwent LF while 142 underwent LP. Of the 108 patients who underwent LF, 79.6% were radiographically deemed candidates for LP, as were all 142 patients who underwent LP. The ICC for C2-C7 alignment was 0.90; there was 97% agreement with respect to the presence of instability.Conclusions: In 250 patients with CSM, 228 (91.2%) were radiographically candidates for LP. These data suggest that LP may be an underutilized procedure for the treatment for CSM. [ABSTRACT FROM AUTHOR]

Background Context: Laminectomy with fusion (LF) and laminoplasty (LP) are commonly used to treat cervical spondylotic myelopathy (CSM). The decision regarding which procedure to perform is largely a matter of surgeon's preference, while financial implications are rarely considered.Purpose: We aimed to better understand the financial considerations of LF compared to LP in the treatment of CSM.Study Design: Retrospective comparative study.Patient Sample: Adult patients, 18 years of age or older, who had undergone LF or LP for CSM from 2017 to 2019 at 2 large academic centers were included. Patients who had undergone previous cervical spine surgery or procedures that extended above C2 or below T2 were excluded.Outcome Measures: The primary outcome was defined as the total cost of the procedure, which was calculated as the sum of the implant and non-implant supply costs.Methods: Patient demographics, surgical parameters, including estimated blood loss and operative time, and length of stay were collected. Operating room material - both implant and non-implant - cost data was also obtained. Variables were analyzed individually as well as after adjustment based on the number of operative levels involved. Statistical analysis was performed using either Student t test with unequal variance or Wilcoxon rank sum test for continuous variables and chi-squared analysis for categorical variables.Results: Two hundred fifty patients were identified who met inclusion criteria. There was no statistical difference in the mean age at time of surgery (p=.25), gender distribution (p=.33), or re-operation rate between the LF and LP groups (p=.39). Overall, operative time was similar between the LF (165.7 ± 61.9 min) and LP (173.8 ± 58.2 min) groups (p=.29), but the LP cohort had a shorter length of stay at 3.8 ± 2.7 days compared to the LF cohort at 4.8 ± 3.7 days. Implant costs in the LF group were significantly more at $6,204.94 ± $1426.41 compared to LP implant costs at $1994.39 ± $643.09. Mean total costs of LP were significantly less at $2,859.08 ± $784.19 compared to LF total costs of $6,983.16 ± $1,589.17. Furthermore, when adjusted for the number of operative levels, LP remained significantly less costly at $766.12 ± $213.64 per level while LF cost $1,789.05 ± $486.66 per operative level. Additional subgroup analysis limiting the cohorts to patients with either three or four involved vertebral levels demonstrated nearly identical cost savings with LP as compared to LF.Conclusions: This study demonstrates that LF is on average at least 2.4 times the total operative supply cost of LP and at least 2.3 times the operative supply cost of LP when adjusted for the number of operative levels. In patients deemed appropriate for either LP or LF, these data may be incorporated into decision-making for the treatment of CSM. [ABSTRACT FROM AUTHOR]

Preoperative MRSA screening and decolonization has demonstrated success for some orthopaedic subspecialties in prevention of surgical site infections (SSIs). Spine surgery, however, has seen varied results, potentially secondary to the anatomic and surgical heterogeneity of the patients included in prior studies. Given that prior research has demonstrated greater propensity for gram positive SSIs in the cervical spine, we sought to investigate if MRSA screening would be more impactful in the cervical spine. The purpose of this study was to determine the relationship between nasal MRSA testing and SSI rates specifically in the setting of primary posterior cervical instrumented spine surgery. Retrospective cohort study. Adult patients undergoing primary instrumented posterior cervical procedures from January 2015-December 2019 at two tertiary academic referral centers in an urban setting Physiologic measures: subfascial presumed infected collection or abscess within 90 days of the index operation. Adult patients undergoing primary instrumented posterior cervical procedures from January 2015-December 2019 were reviewed for MRSA testing < 90-days before surgery, preoperative mupirocin, perioperative antibiotics and SSI defined as operative incision and drainage (I&D) < 90-days after surgery. Trauma, tumor and infection cases were excluded. Logistic regression modeling was used with SSI the primary outcome and MRSA screening the primary predictor with clinical and demographic factors as covariates. This study included 668 patients, of whom MRSA testing was performed in 212 patients (31.7%) and 6 (2.8%) were colonized with MRSA. Twelve patients (1.8%) underwent an I&D. On adjusted analysis, preoperative MRSA testing was not associated with postoperative I&D risk. Perioperative vancomycin similarly had no association with postoperative I&D risk. Notably, six patients (50%) grew MSSA from intraoperative cultures, with no cases of MRSA. There was no association between preoperative nasal MRSA screening and SSIs in primary posterior cervical instrumented procedures, nor was there any association between vancomycin or infection rate. Furthermore, there was a preponderance of gram-positive infections but none caused by MRSA. Given these findings, the considerable cost and effort associated with MRSA testing in the setting of primary posterior cervical instrumentation may not be justified. Further research should investigate if higher-risk scenarios demonstrate greater utility of preoperative testing. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]

Surgical site infections (SSI) constitute significant morbidity in spine surgery. Efforts at SSI prevention include preoperative methicillin-resistant Staphylococcus aureus (MRSA) screening and decolonization, with demonstrated success for arthroplasty patients along with vascular and cardiothoracic surgical patients. The variety of surgical approaches and anatomic regions within spine surgery can limit the impact of analyses at the subspecialty level. Despite the success of MRSA nasal screening and decolonization in reducing SSI rates in other disciplines, the impact on spine surgery is less understood. To determine the relationship between nasal MRSA testing and operative debridement rates for surgical site infection after primary lumbar fusion. Retrospective cohort study at two academic tertiary referral centers. Adult patients (>18 years) were identified from January 2015 to March 2020 based on CPT codes for spinal instrumentation and fusion. Inclusion criteria were primary instrumented posterior lumbar fusion between 1-3 levels and exclusion criteria were revision surgery, tumor, infection, lateral-only surgery or operative surgeon with fewer than 20 cases. Operative incision and drainage (I&D) of the index lumbar spine wound within 90-days after surgery was the primary outcome. Chart text, operative reports and laboratory reports were reviewed for data abstraction. Multivariable logistic regression modeling assessed for demographic differences between MRSA testing groups as well as factors contributing to I&D risk. There were 2,148 patients included with a mean age 62.5 (SD 12.9), 56.9% female, and mean BMI 29.4 (SD 6.2). MRSA testing 90 days prior to surgery was completed in 884 (41.1%) of patients, and 19 (2.2%) of tested patients were colonized with MRSA preoperatively. Thirty-six (1.7%) patients underwent surgical I&D within 90 days of their index procedure for a surgical site infection. I&D risk was not associated with presence or result of MRSA testing, preoperative mupirocin prescriptions, or type of intraoperative antibiotic after controlling for surgeon. I&D risk was associated with higher BMI (5.7% increased risk for every 1 unit increase in BMI or a coefficient of 0.057, 95% confidence interval 0.017 to 0.097, p = 0.005) after controlling for age, diabetes and smoking status. The present study demonstrates no difference in surgical I&D rates between patients who underwent MRSA testing, who had positive MRSA colonization or who underwent other interventions aimed at decreasing SSI rates such as preoperative mupirocin decolonization or addition of intraoperative vancomycin. Increased BMI was associated with risk of undergoing an operative I&D for surgical site infection, suggesting that patient factors dominate over clinical interventions in the prevention of surgical site infection after primary lumbar spine fusion. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]