Faculty Bibliography

BACKGROUND CONTEXT/BACKGROUND:Laboratory values have been found to be useful predictive measures of survival following surgery. The utility of laboratory values for prognosticating outcomes among patients with spinal metastases has not been studied. PURPOSE/OBJECTIVE:To determine the prognostic capacity of laboratory values at presentation including white blood cell count, serum albumin and platelet-lymphocyte ratio (PLR) in patients with spinal metastases. STUDY DESIGN/METHODS:Retrospective review of records from two tertiary care centers (2005-2017). PATIENT SAMPLE/METHODS:Patients, aged 40 to 80, who received operative or nonoperative management for spinal metastases. OUTCOME MEASURES/METHODS:Survival, complications, or hospital readmissions within 90 days of treatment and a composite measure for treatment failure accounting for changes in ambulatory function and mortality at 6 months following presentation. METHODS:Multivariable Cox proportional hazard regression analysis was used to analyze the relationship between laboratory values and length of survival, adjusting for confounders. Multivariable logistic regression was used in analyses related to 6-month and 1-year mortality, complications, readmissions, and treatment failure. A scoring rubric was developed based on the performance of laboratory values in the multivariable tests. Internal validation was performed using a bootstrap simulation that consisted of sampling with replacement and 1,000 replications. RESULTS:We included 1,216 patients. Thirty-seven percent of patients received a surgical intervention and 63% were treated nonoperatively. Median survival for the cohort as a whole was 255 days (interquartile range 93-642 days). The PLR (hazard ratio [HR] 1.53; 95% confidence interval [CI] 1.29, 1.80; p<.001) and albumin (HR 0.54; 95% CI 0.45, 0.64; p<.001) were significantly associated with survival, whereas WBC count (HR 1.08; 95% CI 0.86, 1.36; p=.50) was not associated with this outcome. Similar findings were encountered for 6-month and 1-year mortality as well as the composite measure for treatment failure. The PLR and albumin performed well in our scoring rubric and findings were preserved in the bootstrapping validation. CONCLUSIONS:Individuals with low serum albumin and elevated PLR should be advised regarding the impact of these laboratory markers on outcomes including survival, irrespective of treatments received. An effort should also be made to optimize nutrition and PLR, if practicable, before treatment to minimize the potential for development of adverse events.

Cervical alignment plays a critical role in the diagnosis and treatment of spinal pathology. There has been a proliferation of novel radiographic parameters to quantify cranial and cervical alignment. These parameters have been placed in clinical context by their correlation with health-related quality of life (HRQOL) scores. This article reviews these parameters and describes their utility in understanding spinal deformity and other pathologies of the cervical spine.

OBJECTIVE:Optimal patient selection for upper-thoracic (UT) versus lower-thoracic (LT) fusion during adult spinal deformity (ASD) correction is challenging. Radiographic and clinical outcomes following UT versus LT fusion remain incompletely understood. The purposes of this study were: 1) to evaluate demographic, radiographic, and surgical characteristics associated with choice of UT versus LT fusion endpoint; and 2) to evaluate differences in radiographic, clinical, and health-related quality of life (HRQOL) outcomes following UT versus LT fusion for ASD. METHODS:Retrospective review of a prospectively collected multicenter ASD database was performed. Patients with ASD who underwent fusion from the sacrum/ilium to the LT (T9-L1) or UT (T1-6) spine were compared for demographic, radiographic, and surgical characteristics. Outcomes including proximal junctional kyphosis (PJK), reoperation, rod fracture, pseudarthrosis, overall complications, 2-year change in alignment parameters, and 2-year HRQOL metrics (Lumbar Stiffness Disability Index, Scoliosis Research Society-22r questionnaire, Oswestry Disability Index) were compared after controlling for confounding factors via multivariate analysis. RESULTS:Three hundred three patients (169 LT, 134 UT) were evaluated. Independent predictors of UT fusion included greater thoracic kyphosis (odds ratio [OR] 0.97 per degree, p = 0.0098), greater coronal Cobb angle (OR 1.06 per degree, p < 0.0001), and performance of a 3-column osteotomy (3-CO; OR 2.39, p = 0.0351). While associated with longer operative times (ratio 1.13, p < 0.0001) and greater estimated blood loss (ratio 1.31, p = 0.0018), UT fusions resulted in greater sagittal vertical axis improvement (-59.5 vs -41.0 mm, p = 0.0035) and lower PJK rates (OR 0.49, p = 0.0457). No significant differences in postoperative HRQOL measures, reoperation, or overall complication rates were detected between groups (all p > 0.1). CONCLUSIONS:Greater deformity and need for 3-CO increased the likelihood of UT fusion. Despite longer operative times and greater blood loss, UT fusions resulted in better sagittal correction and lower 2-year PJK rates following surgery for ASD. While continued surveillance is necessary, this information may inform patient counseling and surgical decision-making.

STUDY DESIGN/METHODS:Retrospective cohort. OBJECTIVE:Identify the nonradiographic predictors of a patient's decision to undergo elective spine surgery. SUMMARY OF BACKGROUND DATA/BACKGROUND:Up to 132 million people seek elective evaluation by spine surgeons annually, though 55%-82% of specialty referrals may be inappropriate. We sought to determine which clinical and psychosocial factors are associated with surgical utilization by patients seeking surgical evaluation for degenerative spine pathologies. MATERIALS AND METHODS/METHODS:Consecutive elective outpatient visits seen in a single clinic between May 2016 and April 2017 for degenerative spine pathologies were reviewed. Data were collected on presenting symptoms, baseline medical illness, demographics, and previous spine care. Multivariable logistic regressions were performed to determine which factors were associated with surgical candidacy and surgical utilization. RESULTS:A total of 353 patients were seen during the period reviewed, of which 144 had complete medical records. Our cohort included 90 nonsurgical candidates, 25 surgical candidates who declined surgery, and 29 patients who underwent surgery. In multivariable analysis, factors negatively associated with surgical candidacy were age, a history of smoking, and osteoporosis, where those positively associated with surgical candidacy were reports of spine-specific pain, higher Charlson Comorbidity Index, pain medication use, number of neurological symptoms, and being myelopathic. Factors positively associated with surgical utilization included proportion of all complaints that were neurological in nature, being myelopathic, higher Charlson Comorbidity Index, and report of pain as chronic, whereas being osteoporotic was negatively associated with surgical use. A receiver operating curve constructed for these models produced c-statistics of 0.75 and 0.80, respectively. CONCLUSIONS:Our results suggest that the results of standard clinic intake questions, such as review of systems, medical history, and chief complaints, may be predictive of surgical candidacy before evaluation by a surgeon. The present pilot study suggests a preliminary algorithm that can be further validated and expanded upon to help decide on optimal patient referrals to spine surgery specialists.

OBJECTIVES/OBJECTIVE:Determine significant associations between patient frailty status and odontoid fractures across common traumatic mechanisms of injuries (MOI) in the elderly. DESIGN/METHODS:Retrospective review. SETTING/METHODS:Single, academic-affiliated hospital with full surgical servicesPatients/Participants: Patients >65 years old with traumatic odontoid fracture were included. INTERVENTION/METHODS:Non-operative management (soft/hard collar, halo, traction tongs, minerva) and/or operative fixation. MAIN OUTCOME MEASUREMENTS/METHODS:mFI, MOI, concurrent injuries, inpatient LOS, reoperation and mortality rates. RESULTS:70 patients were included (80.6±8.5yrs, 60%F, 88% European, 10% Maori/Pacific, 1.4% Asian, CCI 5.3± 2.2, mFI 0.21±0.15). The most common MOIs were Falls (74.3%), high speed MVAs (17.1%), low speed MVAs (5.7%), and pedestrian vs car (2.9%). Patients with traumatic falls exhibited significantly higher mFI scores (0.25) compared to low speed MVAs (0.16), high speed MVAs (0.08), and pedestrian vs car (0.01) (p=0.003). Twenty-seven patients with odontoid fractures were Frail, 33 were Pre-frail, and 10 were Robust. 92% of Frail patients had traumatic fall as their MOI, as opposed to 73% of Pre-frail and 30% of Robust patients (p<0.001). Pre-frail and Frail patients were 4.3 times more likely than Robust patients to present with odontoid fractures via traumatic fall (OR: 4.33 [1.47-12.75], p=0.008), and frailty increased likelihood of reoperation (OR: 4.2 [1.2-14.75], p=0.025) and extended LOS (OR: 5.71 [1.05-10.37], p=0.017). Frail patients had the highest 30-day (p=0.017) and 1-year mortality (p<0.001) compared to other groups. CONCLUSION/CONCLUSIONS:Patients with traumatic odontoid fracture from falls were significantly more frail in comparison to any other MOI, with worse short and long-term outcomes. LEVEL OF EVIDENCE/METHODS:Level III Retrospective Cohort Study.

OBJECT/OBJECTIVE:The LSDI assesses the impact of lumbar stiffness on activities of daily living. We hypothesized that patients <60 years-old would perceive greater lumbar stiffness-related functional limitation following fusion for adult spinal deformity. METHODS:Patients completed the LSDI and SRS-22r questionnaires preoperatively and at 2 years postoperatively. The primary independent variable was patient age <60 vs. ≥60 years-old. Multivariable regression analyses were utilized. RESULTS:In total, 267 patients were analyzed. Patients <60 years-old (51.3%) and ≥60 years-old (48.7%) were evenly represented. In bivariable analysis, patients <60 years-old exhibited lower LSDI at baseline vs. patients ≥60 years-old (25.7 vs. 35.5, β -9.8, p<0.0001), but a directionally smaller difference at 2-years (26.4 vs. 32.3, β -5.8, p=0.0147). LSDI was associated with lower SRS-22r total score among both patients <60 and ≥60 years-old, at both baseline and 2-years (all p<0.0001); the association was stronger among patients <60 vs. ≥60 years-old at 2 years. LSDI was associated with SRS satisfaction scores at 2 years among patients <60 years-old (p<0.0001), but not patients ≥60 years-old (p=0.2250). The difference in SRS satisfaction per unit LSDI between patients <60 years-old and >60 years-old was significant (p=0.0021). CONCLUSIONS:Among ASD patients managed operatively, higher LSDI was associated with inferior SRS-22r total score and satisfaction at 2 years postoperatively. The association between increased LSDI and worse PROMs was greater among patients <60 vs. ≥60 years old. Pre-operative counseling is needed for patients <60 undergoing ASD surgery regarding the effects that lumbar stiffness may have on post-operative function and satisfaction.

The AHRQ (Agency for Healthcare Research and Quality) has requested the correction of the result Tables 1-3 of this study: All stated numbers below 10 shall be modified to read "<10" instead.

STUDY DESIGN/METHODS:Multicenter database review of consecutive adult spinal deformity (ASD) patients. OBJECTIVE:The aim of this study was to identify associations between changes in spinopelvic parameters and cervical alignment after thoracolumbar arthrodesis for ASD. SUMMARY OF BACKGROUND DATA/BACKGROUND:Reciprocal cervical changes occur after instrumented thoracic spinal arthrodesis. The timing and relationship of these changes to sagittal alignment and upper instrumented vertebra (UIV) selection are unknown. METHODS:In 171 ASD patients treated with thoracolumbar arthrodesis from 2008 to 2012, we assessed changes from baseline to 6-week, 1-year, and 2-year follow-up in C2-C7 sagittal vertical axis (SVA), T1 slope, and C2-C7 lordosis. We used multivariate models to analyze associations between these parameters and UIV selection (T9 or distal vs. proximal to T9) and changes at each time point in thoracic kyphosis (TK), lumbar lordosis (LL), C7-S1 SVA, pelvic incidence, pelvic tilt, and sacral slope. RESULTS:Two-year changes in C2-C7 SVA and T1 slope were significantly associated with baseline to 6-week changes in TK and LL and with UIV selection. Baseline to 2-year changes in C2-C7 lordosis were associated with baseline to 6-week changes in C7-S1 SVA (P = 0.004). Most changes in C2-C7 SVA occurred during the first 6 weeks postoperatively (mean 6-week change in C2-C7 SVA: 2.7 cm, 95% confidence interval [CI]: 0.7-4.7 cm; mean 2-year change in SVA: 2.3 cm, 95% CI: -0.1 to 4.6 cm). At 2 years, on average, there was decrease in C2-C7 lordosis, most of which occurred during the first 6 weeks postoperatively (mean 6-week change: -3.2°, 95% CI: -4.8° to -1.2°; mean 2-year change: -1.3°, 95% CI: - 3.2° to 0.5°). CONCLUSION/CONCLUSIONS:After thoracolumbar arthrodesis, reciprocal changes in cervical alignment are associated with postoperative changes in TK, LL, and C7-S1 SVA and with UIV selection. The largest changes occur during the first 6 weeks and persist during 2-year follow-up. LEVEL OF EVIDENCE/METHODS:3.

OBJECTIVE:Cervical deformity (CD) is difficult to define due to the high variability in normal cervical alignment based on postural- and thoracolumbar-driven changes to cervical alignment. The purpose of this study was to identify whether patterns of sagittal deformity could be established based on neutral and dynamic alignment, as shown on radiographs. METHODS:This study is a retrospective review of a prospective, multicenter database of CD patients who underwent surgery from 2013 to 2015. Their radiographs were reviewed by 12 individuals using a consensus-based method to identify severe sagittal CD. Radiographic parameters correlating with health-related quality of life were introduced in a two-step cluster analysis (a combination of hierarchical cluster and k-means cluster) to identify patterns of sagittal deformity. A comparison of lateral and lateral extension radiographs between clusters was performed using an ANOVA in a post hoc analysis. RESULTS:Overall, 75 patients were identified as having severe CD due to sagittal malalignment, and they formed the basis of this study. Their mean age was 64 years, their body mass index was 29 kg/m2, and 66% were female. There were significant correlations between focal alignment/flexibility of maximum kyphosis, cervical lordosis, and thoracic slope minus cervical lordosis (TS-CL) flexibility (r = 0.27, 0.31, and -0.36, respectively). Cluster analysis revealed 3 distinct groups based on alignment and flexibility. Group 1 (a pattern involving a flat neck with lack of compensation) had a large TS-CL mismatch despite flexibility in cervical lordosis; group 2 (a pattern involving focal deformity) had focal kyphosis between 2 adjacent levels but no large regional cervical kyphosis under the setting of a low T1 slope (T1S); and group 3 (a pattern involving a cervicothoracic deformity) had a very large T1S with a compensatory hyperlordosis of the cervical spine. CONCLUSIONS:Three distinct patterns of CD were identified in this cohort: flat neck, focal deformity, and cervicothoracic deformity. One key element to understanding the difference between these groups was the alignment seen on extension radiographs. This information is a first step in developing a classification system that can guide the surgical treatment for CD and the choice of fusion level.

OBJECTIVE:Cervical deformity (CD) correction is clinically challenging. There is a high risk of developing complications with these highly complex procedures. The aim of this study was to use baseline demographic, clinical, and surgical factors to predict a poor outcome following CD surgery. METHODS:The authors performed a retrospective review of a multicenter prospective CD database. CD was defined as at least one of the following: cervical kyphosis (C2-7 Cobb angle > 10°), cervical scoliosis (coronal Cobb angle > 10°), C2-7 sagittal vertical axis (cSVA) > 4 cm, or chin-brow vertical angle (CBVA) > 25°. Patients were categorized based on having an overall poor outcome or not. Health-related quality of life measures consisted of Neck Disability Index (NDI), EQ-5D, and modified Japanese Orthopaedic Association (mJOA) scale scores. A poor outcome was defined as having all 3 of the following categories met: 1) radiographic poor outcome: deterioration or severe radiographic malalignment 1 year postoperatively for cSVA or T1 slope-cervical lordosis mismatch (TS-CL); 2) clinical poor outcome: failing to meet the minimum clinically important difference (MCID) for NDI or having a severe mJOA Ames modifier; and 3) complications/reoperation poor outcome: major complication, death, or reoperation for a complication other than infection. Univariate logistic regression followed by multivariate regression models was performed, and internal validation was performed by calculating the area under the curve (AUC). RESULTS:In total, 89 patients with CD were included (mean age 61.9 years, female sex 65.2%, BMI 29.2 kg/m2). By 1 year postoperatively, 18 (20.2%) patients were characterized as having an overall poor outcome. For radiographic poor outcomes, patients' conditions either deteriorated or remained severe for TS-CL (73% of patients), cSVA (8%), horizontal gaze (34%), and global SVA (28%). For clinical poor outcomes, 80% and 60% of patients did not reach MCID for EQ-5D and NDI, respectively, and 24% of patients had severe symptoms (mJOA score 0-11). For the complications/reoperation poor outcome, 28 patients experienced a major complication, 11 underwent a reoperation, and 1 had a complication-related death. Of patients with a poor clinical outcome, 75% had a poor radiographic outcome; 35% of poor radiographic and 37% of poor clinical outcome patients had a major complication. A poor outcome was predicted by the following combination of factors: osteoporosis, baseline neurological status, use of a transition rod, number of posterior decompressions, baseline pelvic tilt, T2-12 kyphosis, TS-CL, C2-T3 SVA, C2-T1 pelvic angle (C2 slope), global SVA, and number of levels in maximum thoracic kyphosis. The final model predicting a poor outcome (AUC 86%) included the following: osteoporosis (OR 5.9, 95% CI 0.9-39), worse baseline neurological status (OR 11.4, 95% CI 1.8-70.8), baseline pelvic tilt > 20° (OR 0.92, 95% CI 0.85-0.98), > 9 levels in maximum thoracic kyphosis (OR 2.01, 95% CI 1.1-4.1), preoperative C2-T3 SVA > 5.4 cm (OR 1.01, 95% CI 0.9-1.1), and global SVA > 4 cm (OR 3.2, 95% CI 0.09-10.3). CONCLUSIONS:Of all CD patients in this study, 20.2% had a poor overall outcome, defined by deterioration in radiographic and clinical outcomes, and a major complication. Additionally, 75% of patients with a poor clinical outcome also had a poor radiographic outcome. A poor overall outcome was most strongly predicted by severe baseline neurological deficit, global SVA > 4 cm, and including more of the thoracic maximal kyphosis in the construct.