The demographic, clinical, and management differences between traumatic dens fracture patients with and without simultaneous atlas fractures.

Introduction: Atlas fractures often accompany traumatic dens fractures, but existing literature on the management of simultaneous atlantoaxial fractures is limited. Methods: We examined all patients with traumatic dens fractures at our institution between 2008 and 2018. We used multivariable logistic regression and ordinal logistic regression to identify factors independently associated with presentation with a simultaneous atlas fracture, as well myelopathy severity, fracture nonunion, and selection for surgery. Results: Two hundred and eighty-two patients with traumatic dens fractures without subaxial fractures were identified, including 65 (22.8%) with simultaneous atlas fractures. The distribution of injury mechanisms differed between groups (χ2 P = 0.0360). On multivariable logistic regression, dens nonunion was positively associated with type II fractures (odds ratio [OR] = 2.00, P = 0.038) and negatively associated with having surgery (OR = 0.52, P = 0.049), but not with having a C1 fracture (P = 0.3673). Worse myelopathy severity on presentation was associated with having a severe injury severity score (OR = 102.3, P < 0.001) and older age (OR = 1.28, P = 0.002), but not with having an atlas fracture (P = 0.2446). Having a simultaneous atlas fracture was associated with older age (OR = 1.29, P = 0.024) and dens fracture angulation (OR = 2.62, P = 0.004). Among patients who underwent surgery, C1/C2 posterior fusion was the most common procedure, and having a simultaneous atlas fracture was associated with selection for occipitocervical fusion (OCF) (OR = 14.35, P = 0.010). Conclusions: Among patients with traumatic dens, patients who have simultaneous atlas fractures are a distinct subpopulation with respect to age, mechanism of injury, fracture morphology, and management. Traumatic dens fractures with simultaneous atlas fractures are independently associated with selection for OCF rather than posterior cervical fusion alone.

Atlas fractures with and without simultaneous dens fractures differ with respect to clinical, demographic, and management characteristics.

Background: Patients with simultaneous fractures of the atlas and dens have traditionally been managed according to the dens fracture's morphology, but data supporting this practice are limited. Methods: We retrospectively examined all patients with traumatic atlas fractures at our institution between 2008 and 2016. We used multivariable regression and propensity score matching to compare the presentation, management, and outcomes of patients with isolated atlas fractures to patients with simultaneous atlas-dens fractures. Results: Ninety-nine patients were identified. Patients with isolated atlas fractures were younger (61 ± 22 vs. 77 ± 14, P = 0.0003), had lower median Charlson Comorbidity Index (3 vs. 5, P = 0.0005), had better presenting Nurick myelopathy scores (0 vs. 3, P < 0.0001), and had different mechanisms of injury (P = 0.0011). Multivariable regression showed that having a simultaneous atlas-dens fracture was independently associated with older age (odds ratio [OR] =1.59 [1.22, 2.07], P = 0.001), worse presenting myelopathy (OR = 3.10 [2.04, 4.16], P < 0.001), and selection for surgery (OR = 4.91 [1.10, 21.97], P = 0.037). Propensity score matching yielded balanced populations (Rubin's B = 23.3, Rubin's R = 1.96) and showed that the risk of atlas fracture nonunion was no different among isolated atlas fractures compared to simultaneous atlas-dens fractures (P = 0.304). Age was the only variable independently associated with atlas fracture nonunion (OR = 2.39 [1.15, 5.00], P = 0.020), having a simultaneous atlas-dens fracture was not significant (P = 0.2829). Conclusions: Among patients with atlas fractures, simultaneous fractures of the dens occur in older patients and confer an increased risk of myelopathy and requiring surgical stabilization. Controlling for confounders, the risk of atlas fracture nonunion is equivalent for isolated atlas fractures versus simultaneous atlas-dens fractures.

Anterior approach lumbar fusions cause a marked increase in thromboembolic events: Causal inferences from a propensity-matched analysis of 1147 patients.

OBJECTIVE: Anterior lumbar fusions are thought to be associated with elevated venous thromboembolic event (VTE) rates, but the magnitude of this increase in VTE is not well described. The objective of this study was to quantify any increase in VTE caused by anterior approach lumbar fusion. METHODS: 1147 consecutive lumbar fusions performed at our institution over a six-year period were identified, and clinical and demographic data were collected. K-nearest neighbor propensity score matching and propensity score adjusted regression were performed. Patients undergoing anterior versus posterior approach lumbar fusions were matched according to age, body mass index, sex, VTE history, estimated blood loss, length of surgery, transfusion, selection for postoperative intensive care unit (ICU) admission, comorbid disease burden, and use of chemoprophylactic anticoagulation. RESULTS: Anterior approach surgery (OR=4.29, p < 0.001), a history of VTE (OR=8.67, p < 0.001), age (OR=1.53, p = 0.014), length of surgery (OR=1.16, p = 0.044), and selection for postoperative ICU admission (OR=4.60, p = 0.005) were independently associated with VTE on multivariable regression. 1058 anterior or posterior approach fusion patients were matched. After matching, overall bias was reduced by 71.0 %, no covariates remained significantly different between groups, and propensity scores were well balanced between populations (Rubin's B≤0.25, 0.5 ≤Rubin's R≤2.0). Significantly more patients in the anterior group underwent lower extremity duplex ultrasonography (LED) (36.9 % vs. 14.8 %, OR=3.36 [2.38, 4.76], p < 0.0001), and a statistically insignificantly higher proportion of LEDs were positive among patients in the anterior group (23.2 % vs. 13.2 %, OR=1.99 [0.92, 4.25], p = 0.108). After matching, the rate of VTE was 8.6 % for the anterior group and 1.3 % for the posterior group, with anterior approach surgery causing an increase in VTE by 7.2 % (95 % CI [2.28 %, 12.16 %], p = 0.004). CONCLUSION: Among patients undergoing lumbar fusions, anterior approach surgery causes an increase in VTE by 7.2%, which is a multifold increase in the proportion of patients with thromboembolic complications.

Frailty predicts readmission, reoperation, and infection after posterior spinal fusion: An institutional series of 3965 patients.

OBJECTIVE: Frailty is a measure of physiologic vulnerability conceptualized as the accumulation of deficits with aging, and may be useful for predicting risk of adverse events following posterior spinal fusion. Our objective was to investigate the utility of the Canadian Study on Health and Aging (CHSA) Modified Frailty Index (mFI) in patients undergoing posterior spinal fusion (PSF) as a predictor of several surgical quality metrics including readmission, reoperation, and surgical site infection. METHODS: We examined 3965 consecutive PSF patients treated at our institution between 2000 and 2015, and collected demographic, clinical, and frailty and comorbid disease burden measures using the mFI and Charlson Comorbidity Index (CCI). We examined trends and changes in these clinical and demographic characteristics over the course of the study period. We performed multivariable regression to identify independent predictors of readmission, reoperation, and surgical site infection. RESULTS: Over the course of the study period, the mean patient age increased linearly year-over-year (ß=0.60 [0.48, 0.72], p < 0.0001, R=0.94), while the SSI rate decreased linearly (ß=-0.14 [-0.27, -0.02], p = 0.0249, R=0.56), and frailty scores did not change significantly (p = 0.8124, R=0.065). Among all patients undergoing PSF, postoperative wound infection was independently associated with number of levels fused (OR=1.104 p < 0.001), frailty as measured by mFI (OR=1.150 p = 0.006), and BMI (OR=1.041 p = 0.008). Frailty was also independently associated with postoperative ICU admission (OR=1.1080 p = 0.005), 30-day readmission (OR=1.181 p < 0.001), and 30-day reoperation (OR=1.128 p < 0.001). Among all patients, rate of postoperative wound infection increased with increasing frailty (p = 0.0002) and increasing comorbid disease burden (chi-square p = 0.0012). CONCLUSION: The mFI predicts adverse events among patients undergoing PSF, including readmission, reoperation, and surgical site infection. When controlling for frailty, age was not an independent predictor of adverse events.

Surgical Site Infection in the Intensive Care Setting After Posterior Spinal Fusion: A Case Series Highlighting the Microbial Profile, Risk Factors, and the Importance of Comorbid Disease Burden.

BACKGROUND: Most posterior spinal fusion (PSF) patients do not require admission to an intensive care unit (ICU), and those who do may represent an underinvestigated, high-risk subpopulation. OBJECTIVE: To identify the microbial profile of and risk factors for surgical site infection (SSI) in PSF patients admitted to the ICU postoperatively. METHODS: We examined 3965 consecutive PSF patients treated at our institution between 2000 and 2015 and collected demographic, clinical, and procedural data. Comorbid disease burden was quantified using the Charlson Comorbidity Index (CCI). We performed multivariable logistic regression to identify risk factors for SSI, readmission, and reoperation. RESULTS: Anemia, more levels fused, cervical surgery, and cerebrospinal fluid leak were positively associated with ICU admission, and minimally invasive surgery was negatively associated. The median time to infection was equivalent for ICU patients and non-ICU patients, and microbial culture results were similar between groups. Higher CCI and undergoing a staged procedure were associated with readmission, reoperation, and SSI. When stratified by CCI into quintiles, SSI rates show a strong linear correlation with CCI ( P = .0171, R = 0.941), with a 3-fold higher odds of SSI in the highest risk group than the lowest (odds ratio = 3.15 [1.19, 8.07], P = .032). CONCLUSION: Procedural characteristics drive the decision to admit to the ICU postoperatively. Patients admitted to the ICU have higher rates of SSI but no difference in the timing of or microorganisms that lead to those infections. Comorbid disease burden drives SSI in this population, with a 3-fold greater odds of SSI for high-risk patients than low-risk patients.

Risk Factors for Fracture Nonunion and Transverse Atlantal Ligament Injury After Isolated Atlas Fractures: A Case Series of 97 Patients.

BACKGROUND: The management of atlas fractures is controversial and hinges on the integrity of transverse atlantal ligament (TAL). OBJECTIVE: To identify risk factors for atlas fracture nonunion, with and without TAL injury. METHODS: All isolated, traumatic atlas fractures treated at our institution between 1999 and 2016 were analyzed. Multivariable logistic regression was used to identify variables associated with TAL injury confirmed on MRI, occult TAL injury seen on MRI but not suspected on computed tomography (CT), and with fracture nonunion on follow-up CT at 12 weeks. RESULTS: Lateral mass displacement (LMD) ≥ 7 mm had a 48.2% sensitivity, 98.3% specificity, and 82.6% accuracy for identifying TAL injury. MRI-confirmed TAL injury was independently associated with LMD > 7 mm ( P = .004) and atlanto-dental interval ( P = .039), and occult TAL injury was associated with atlanto-dental interval ( P = .019). Halo immobilization was associated with having a Gehweiler type 3 fracture ( P = .020), a high-risk injury mechanism ( P = .023), and an 18.1% complication rate. Thirteen patients with TAL injury on MRI and/or LMD ≥ 7 mm were treated with a cervical collar only, and 11 patients (84.6%) healed at 12 weeks. Nonunion rates at 12 weeks were equivalent between halo (11.1%) and cervical collar (12.5%). Only age independently predicted nonunion at 12 weeks ( P = .026). CONCLUSION: LMD > 7 mm on CT is not sensitive for TAL injury. Some atlas fractures with TAL injury can be managed with a cervical collar. Nonunion rates are not different between halo immobilization and cervical collar, but a strong selection bias precludes directly comparing the efficacy of these modalities. Age independently predicts nonunion.

Traumatic atlas fracture patients comprise two subpopulations with distinct demographics and mechanisms of injury.

BACKGROUND: Atlas fractures account for as much as 13% of cervical fractures, yet their epidemiology and its implications remain under-examined. METHODS: We retrospectively analyzed 97 consecutive cases of isolated, traumatic atlas fractures at our institution over a 17-year period with respect to demographic, clinical, and outcomes data. Unique patient subsets were identified and compared across these parameters. RESULTS: The age of atlas fracture patients showed a bimodal distribution and strong goodness of fit, with one mean centered at an age of 30 years for patients age< 50 (R=0.9409) and mean age of 74 among patients age≥ 50 (R=0.8584). Young patients were more likely to have a high-risk mechanism of injury (57.8% vs. 11.5%, OR=10.49 [3.59, 29.65], p < 0.0001) and injuries while intoxicated (13.3% vs. 0%, OR ∞ [1.704, ∞], p = 0.0082). A greater portion of young patients were managed with halo (33.3% vs. 13.5%, OR=3.21 [1.20, 8.13, p = 0.0281]). Among patients who were managed with halo, a greater proportion had halo-related complications among patients age≥ 50 (57.1% vs. 6.7%, OR=18.67 [1.55, 239.1], p = 0.0207). The median age of atlas fractures increased by ~2.6 years annually (slope 2.637, p < 0.0001, R=0.8079). CONCLUSIONS: The atlas fracture patient population may comprise two distinct subpopulations, distinguished by differences in age and mechanism of injury that lead to divergent management decisions. While halo immobilization has a low rate of complications among patients age< 50, the complication among patients age≥ 50 was significantly higher. The median age of atlas fracture patients increased linearly during the study period, highlighting the importance of age-related differences in management.

Concomitant cervical spine fractures are the primary driver of disability after traumatic vertebral artery dissection: A Case series of 123 patients.

Background: Traumatic vertebral artery dissections (tVADs) occur in up to 20% of patients with head trauma, yet data on their presentation and associated sequelae are limited. Aims and Objectives: To characterize the tVAD population and identify factors associated with clinical outcomes. Materials and Methods: We retrospectively analyzed all cases of tVAD at our institution from January 2004 to December 2018 with respect to mechanism of injury, clinical presentation, anatomic factors, associated pathologies, and relevant outcomes. Results: Of the 123 patients with tVAD, the most common presenting symptoms were neck pain (n=76, 67.3%), headache (57.5%), and visual changes (29.6%). 101 cases (82.1%) were unilateral, and 22 cases (17.9%) were bilateral. V2 was the most involved anatomic segment (83 cases, 70.3). 30 cases (25.4%) led to stroke, and 39 cases (31.7%) had a concomitant cervical fracture. The anatomic segment and number of segments involved, and baseline clinical and demographic characteristics were not associated with risk of stroke. Patients with associated fractures were older (50.3 years v. 36.4 years, p=0.0233), had a higher comorbid disease burden (CCI 1 vs. CCI 1, p<0.0007), were more likely to smoke (OR 3.0 [1.2178, 7.4028], p=0.0202), be male (OR 7.125 [3.0181, 16.8236], p<0.0001), and have mRS≥3 at discharge (OR 3.0545 [1.0937, 8.5752], p=0.0449). On multivariable regression, only fracture independently predicted mRS≥3 at discharge (OR 5.6898 [1.5067, 21.4876], p=0.010). Conclusion: tVADs may be associated with stroke and/or cervical fracture. Presenting symptoms predict stroke, but baseline demographic and clinical characteristics do not. Comorbid cervical fractures, not stroke, drive negative outcomes.

Predictors of patient satisfaction and survey participation after spine surgery: a retrospective review of 17,853 consecutive spinal patients from a single academic institution. Part 2: HCAHPS.

OBJECTIVEPatient satisfaction is a new and important metric in the American healthcare system. The Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) is a common modality used to assess patient satisfaction in inpatient settings. Despite the existence of data, neurosurgical literature on patient satisfaction following spinal surgery is scarce.METHODSA total of 17,853 patients who underwent spinal procedures at the authors' institution were analyzed retrospectively for HCAHPS survey participation. Appropriate demographic, surgical, comorbidity, and complication data were collected; 1118 patients had patient satisfaction survey data, and further survey metrics were collected for this subset of patients.RESULTSMale patients, patients with urgent/emergency procedures, and patients with a longer length of stay were less likely to complete an HCAHPS survey (OR 0.820, p < 0.001; OR 0.818, p = 0.042; and OR 0.983, p < 0.001, respectively). Posterior approach was negatively associated with HCAHPS survey participation (OR 0.868, p = 0.007). Patients undergoing fusion procedures were more likely to participate in HCAHPS surveys (OR 1.440, p < 0.001). Of the completed HCAHPS surveys, there were no positive predictors associated with perfect scores. High Charlson Comorbidity Index (OR 0.931, p = 0.007), increasing elapsed time since surgery or discharge (OR 0.992, p = 0.004), and increasing length of stay (OR 0.928, p < 0.001) were all negatively associated with a perfect score. Finally, patient sex and race did not influence the likelihood of a perfect or low survey score.CONCLUSIONSParticipation in HCAHPS surveys was correlated with preoperative and postoperative factors. Among these, procedure approach and type, length of stay, and complications seemed to influence participation the most. No factors were associated with an increased likelihood of receiving a perfect score. Similarly, length of stay and time elapsed since surgery to survey completion were significant negative predictors of receiving perfect HCAHPS survey scores. Increasing comorbid burden was also found to be a negative predictor for high scores. Further study on predictors of inpatient satisfaction within spine surgery is needed.

Predictors of patient satisfaction and survey participation after spine surgery: a retrospective review of 17,853 consecutive spinal patients from a single academic institution. Part 1: Press Ganey.

OBJECTIVEPress Ganey surveys are common modalities used to assess patient satisfaction scores in an outpatient setting. Despite the existence of data, neurosurgical and orthopedic literature on patient satisfaction following spinal surgery is scarce.METHODSA total of 17,853 patients who underwent spinal procedures at the authors' institution were analyzed retrospectively for Press Ganey survey participation. Appropriate demographic, surgical, comorbidity, and complication data were collected; 1936 patients had patient satisfaction survey data, and further survey metrics were collected for this subset of patients.RESULTSMale patients, patients with urgent/emergency procedures, and patients with longer length of stay (LOS) were less likely to fill out Press Ganey surveys (OR 0.822, p < 0.001; OR 0.781, p = 0.010; and OR 0.983, p < 0.001, respectively). Posterior approach was negatively associated with Press Ganey participation (OR 0.907, p = 0.055). Patients undergoing fusion procedures were more likely to participate in Press Ganey surveys (OR 1.419, p < 0.001). Of the patients who filled out surveys, there were no positive predictors associated with receiving perfect scores on Press Ganey surveys. High Charlson Comorbidity Index (OR 0.959, p = 0.02), increasing elapsed time since surgery or discharge (OR 0.996, p = 0.03), and increasing LOS (OR 0.965, p = 0.009) were all negatively associated with receiving a perfect score. Patients who underwent a posterior-approach procedure compared with other approaches were less likely to report a low Press Ganey score (OR 0.297, p = 0.046). Patient sex and race did not influence the likelihood of receiving perfect or low Press Ganey scores. Finally, the perceived skill of the surgeon was not a significant predictor for perfect (p > 0.99) or low (p = 0.828) Press Ganey scores.CONCLUSIONSPatient participation in Press Ganey surveys strongly correlated with preoperative factors such as procedure approach and type, as well as postoperative factors such as LOS and complications. No factors were associated with an increased likelihood of receiving a perfect Press Ganey score. Similarly, LOS and time elapsed since surgery to survey completion were significant negative predictors of perfect Press Ganey scores. Skill of surgeon, sex, and race did not correlate with a predictive value for Press Ganey outcomes. In addition, overall comorbid disease burden was found to be a significant negative predictor for high patient satisfaction scores. Further study on predictors of patient satisfaction within spine surgery is needed to better assist physicians in improving the surgical experience for patients.

Factors associated with venous thromboembolic events following ICU admission in patients undergoing spinal surgery: an analysis of 1269 consecutive patients.

In BriefIn a retrospective study the authors examined 1269 patients who underwent spinal surgery and were admitted to the intensive care unit (ICU) and identified factors that are associated with venous thromboembolic events (VTEs) in this "high risk" group. Amongst these high-risk factors were: surgeries longer than 4 hours, comorbid disease, patients needing an osteotomy, and patients undergoing spinal stabilization for fractures. Identification of factors that can be optimized prior to surgery will decrease the rates of VTE.

Tract-Specific Volume Loss on 3T MRI in Patients With Cervical Spondylotic Myelopathy.

STUDY DESIGN: Case-control. OBJECTIVE: The aim of this study was to understand the role of high-resolution magnetic resonance (MR) in identifying regional cord volume loss in cervical spondylotic myelopathy (CSM). SUMMARY OF BACKGROUND DATA: Preliminary studies suggest that compression of the ventral region of the cord may contribute disproportionately to CSM symptomology; however, tract-specific data are lacking in the CSM population. The current study is the first to use 3T MR imaging (MRI) images of CSM patients to determine specific volume loss at the level of detail of individual descending white matter tracts. METHODS: Twelve patients with CSM and 14 age-matched were enrolled prospectively and underwent 3-Tesla MRI of the cervical spine. Using the high-resolution images of the spinal cord, straightening and alignment with a template was performed and specific spinal cord tract volumes were measured using Spinal Cord Tool-box version 3.0.7. Modified Japanese orthopedic association (mJOA) and Nurick disability scores were collected in a prospective manner and were analyzed in relation to descending spinal tract volumes. RESULTS: Having CSM was predicted by anterior/posterior diameter, eccentricity of the cord [odds ratio (OR) 0.000000621, P = 0.004], ventral reticulospinal tract volume (OR 1.167, P = 0.063), lateral corticospinal tract volume (OR 1.034, P = 0.046), rubrospinal tract volume (OR 1.072, P = 0.011), and ventrolateral reticulospinal tract volume (OR 1.474, P = 0.005) on single variable logistic regression. Single variable linear regression showed decreases in anterior/posterior spinal cord diameter (P = 0.022), ventral reticulospinal tract volumes (P = 0.007), and ventrolateral reticulospinal tract volumes (P = 0.017) to significantly predict worsening mJOA scores. Similarly, decreases in ventral reticulospinal tract volumes significantly predicted increasing Nurick scores (P = 0.039). CONCLUSION: High-resolution 3T MRI can detect tract-specific volume loss in descending spinal cord tracts in CSM patients. Anterior/posterior spinal cord diameter, ventral reticulospinal tract, ventrolateral reticulospinal tract, lateral corticospinal tract, and rubrospinal tract volume loss are associated with CSM symptoms. LEVEL OF EVIDENCE: 2.

Management of Isolated Atlas Fractures: A Retrospective Study of 65 Patients.

BACKGROUND: Jefferson fractures, or burst fractures of the C1 vertebra, can be managed surgically or conservatively, depending on their stability. METHODS: We identified all patients who were treated for a C1 fracture at our institution between 1999 and 2016 for retrospective analysis. Patients with any other concurrent cervical fractures or nontraumatic etiology of fracture were excluded. Stability was defined as either lateral mass displacement ≥7 mm on computed tomography or presence of transverse atlantal ligament disruption on magnetic resonance imaging. We collected data on patients' demographic, clinical, and radiographic presentation and identified variables independently associated with instability at presentation and failure to achieve fusion at follow-up. RESULTS: We identified 65 patients. On multivariable regression, instability at presentation was independently associated with atlantodens interval (odds ratio [OR] 2.357, 95% confidence interval [CI] [0.0629-1.271], P = 0.099) and type 3 fracture (OR 6.081, 95% CI [1.068-34.612], P = 0.042). Failure to achieve fusion was independently associated with age (OR 1.226, 95% CI [1.007-1.495], P = 0.043), motor vehicle collision as mechanism of injury (OR 22834.3, 95% CI [3.135-1.66e8], P = 0.027), and type 2 fracture (OR 168.537, 95% CI [1.743-16292.92], P = 0.028). Type 3 fracture was positively associated with halo vest for management (OR 17.171, 95% CI [2.882-102.289], P = 0.002) and negatively associated with a rigid cervical collar for management (OR 0.0616, 95% CI [0.0104-0.3653], P = 0.002). All 4 patients who underwent surgery presented with unstable fracture (P = 0.0187). CONCLUSIONS: Atlantodens interval, mechanism of injury, and fracture type affect Jefferson fracture management decisions and outcomes, including instability at presentation and fusion at follow-up. Most fractures were managed nonsurgically regardless of stability.

Quantitative Magnetization Transfer MRI Measurements of the Anterior Spinal Cord Region are Associated With Clinical Outcomes in Cervical Spondylotic Myelopathy.

STUDY DESIGN: A case-control study. OBJECTIVE: The aim of this study was to understand the role of magnetization transfer ratio (MTR) in identifying patients with clinically significant myelopathy and disability. SUMMARY OF BACKGROUND DATA: MTR is a quantitative measure that correlates with myelin loss and neural tissue destruction in a variety of neurological diseases. However, the usefulness of MTR in patients with cervical spondylotic myelopathy (CSM) has not been examined. METHODS: We prospectively enrolled seven CSM patients and seven age-matched controls to undergo magnetic resonance imaging (MRI) of the cervical spine. Nurick, Neck Disability Index (NDI), and modified Japanese Orthopedic Association (mJOA) scores were collected for all patients. Clinical hyperreflexia was tested at the MCP joint, using a six-axis load cell. Reflex was simulated by quickly moving the joint from maximum flexion to maximum extension (300°/second). Anterior, lateral, and posterior cord MTR measurements were compared with clinical outcomes. RESULTS: Compared with controls, CSM patients had lower anterior cord MTR (38.29 vs. 29.97, Δ = -8.314, P = 0.0022), and equivalent posterior cord (P = 0.2896) and lateral cord (P = 0.3062) MTR. Higher Nurick scores were associated with lower anterior cord MTR (P = 0.0205), but not lateral cord (P = 0.5446) or posterior cord MTR (P = 0.1222). Lower mJOA was associated with lower anterior cord MTR (P = 0.0090), but not lateral cord (P = 0.4864) or posterior cord MTR (P = 0.4819). There was no association between NDI and MTR of the anterior (P = 0.4351), lateral (P = 0.7557), or posterior cord (P = 0.9171). There was a linear relationship between hyperreflexia and anterior cord MTR (slope = -117.3, R = 0.6598, P = 0.0379), but not lateral cord (P = 0.1906, R = 0.4511) or posterior cord (P = 0.2577, R = 0.3957) MTR. CONCLUSION: Anterior cord MTR correlates with clinical outcomes as measured by mJOA index, Nurick score, and quantitative hyperreflexia, and could play a role in the preoperative assessment of CSM. LEVEL OF EVIDENCE: 2.

The safety of resection for primary central nervous system lymphoma: a single institution retrospective analysis.

Surgical resection is not the standard of care for primary central nervous system lymphoma (PCNSL), as historical studies have demonstrated unfavorable complication rates and limited benefits. Some recent studies suggest that resection may provide a therapeutic benefit, yet the safety of these procedures has not been systematically investigated in the setting of modern neurosurgery. We examined the safety of surgical resection for PCNSL. We retrospectively analyzed all patients with PCNSL treated at Columbia University Medical Center between 2000 and 2015 to assess complications rates following biopsy or resection using the Glioma Outcomes Project system. We identified predictors of complications and selection for resection. Well-validated scales were used to quantify patients' baseline clinical characteristics, including functional status, comorbid disease burden, and cardiac risk. The overall complication rate was 17.2% after resection, and 28.2% after biopsy. Cardiac risk (p = 0.047, OR 1.72 [1.01, 2.95]), and comorbid diagnoses (p = 0.004, OR 3.05 [1.42, 6.57]) predicted complications on multivariable regression. Patients who underwent resection had better KPS scores (median 70 v. 80, p = 0.0068, ∆ 10 [0.0, 10.00]), and were less likely to have multiple (46.5% v. 27.6%, p = 0.030, OR 1.42 [1.05, 1.92]) or deep lesions (70.4% v. 39.7%, p = 0.001, OR 1.83 [1.26, 2.65]). Age (p = 0.048, OR 0.75 per 10-year increase [0.56, 1.00]) and deep lesions (p = 0.003, OR 0.29 [0.13, 0.65]) influenced selection for resection on multivariable regression. Surgical resection of PCNSL is safe for select patients, with complication rates comparable to rates for other intracranial neoplasms. Whether there is a clinical benefit to resection cannot be concluded.