Faculty Bibliography

BACKGROUND CONTEXT: The Scoliosis Research Society established appropriateness criteria for surgery for degenerative lumbar scoliosis (DLS) in order to improve and unify clinical decision making. Though utilized and validated in various cohorts, an appropriateness criteria has yet to be developed in a cervical deformity (CD) population. PURPOSE: To modify the DLS Appropriateness criteria to be utilized in a CD cohort. STUDY DESIGN/SETTING: Retrospective review of a single-surgeon CD database PATIENT SAMPLE: A total of 100 CD patients. OUTCOME MEASURES: Appropriateness criteria.
METHOD(S): CD patients>18yrs were included. Each patient was scored based upon the SRS-appropriateness criteria, comprised of clinical or radiographic characteristics and was modified for a cervical deformity cohort: (1) Severity of Symptoms [NDI], (2) Severity of Myelopathy[mJOA.], (3) Progression of Deformity, (4) Global Sagittal Malalignment [Schwab modifiers], (5) Severity of Risk Factors, (6) Degree of the T1S-CL curvature. For the category 'progression', radiographs were only available at one preoperative time point, and we were unable to include this in the total score. Based upon certain combinations of criteria, patients were stratified into Appropriate and Not Appropriate.
RESULT(S): A total of 100 patients were included (61yrs, 62% F, 29.5kg/m²). Assessment of the categories of Appropriateness of CD surgery: (1) Symptoms: 6% None to Mild, 94% Moderate to Severe; (2) Myelopathy: 16% None to Mild, 45% Moderate, 39% Severe; (3) All were grouped No Progression in the present study; (4) 19% demonstrated Global Malalignment (+/++Schwab), 81% did not; (5) Risk Factors: 27% had None to Mild, 63% Moderate, 10% Severe; (6) Curvature TS-CL demonstrated 88.6% of patients Severe (>20degree). Not Appropriate: None to Mild (NDI <28), with (1) None to Moderate myelopathy (mJOA >12) and Severe Risk Factors (2) None to Mild myelopathy (15-18) and No Progression or Imbalance (3) Moderate myelopathy (mJOA 12-15) and None to Moderate Risk Factors and no Progression, or imbalance and TSCL <25degree. Appropriate: Moderate to Severe Symptoms (NDI >=30), with (1) Severe myelopathy (mJOA<12) and Any Risk Factors (2) Moderate myelopathy and None to Moderate Risk Factors (3) Moderate myelopathy with Severe Risk Factors, Progression AND Imbalance (4) None to Mild myelopathy and None to Moderate Risk Factors and Progression OR imbalance (5) None to Mild myelopathy with None to Moderate Risk Factors and TSCL >25degree. In the present cohort, 94% were deemed Appropriate for surgery, 6% Not Appropriate. Less Appropriate patients demonstrated higher rates of postop dysphagia complications (17% vs 2%), met MCID for NDI less (0% vs 30.9%), and had more occurrences of DJK (16.7% vs 6.4%) by 2 years, p<0.05.
CONCLUSION(S): In light of the heterogeneity and uncertainty surrounding CD, this study developed CD appropriateness criteria, using established methodology, for surgeons to consider in the preoperative decision-making that correlate well with major postop occurrences. Application of the appropriateness criteria for CD may optimize patient selection and reduce the incidence of unwarranted surgery, although future validation is necessary. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Following cervical deformity (CD) corrective surgery, durability remains a challenge and distal junctional kyphosis (DJK) is an important risk for a surgeon to consider. DJK is the result from fixation failure, adjacent level fracture or spondylolisthesis. The timing of DJK onset has yet to be investigated. PURPOSE: To determine the timing of DJK development following CD corrective surgery. STUDY DESIGN/SETTING: Retrospective review. PATIENT SAMPLE: A total of 139 CD patients. OUTCOME MEASURES: Early/Late DJK Development, Severe DJK, Symptomatic DJK.
METHOD(S): Included: surgical CD patients (C2-C7 Cobb>10degree, CL>10degree, cSVA>4cm, or CBVA>25degree) without preop DJK. DJK angle was defined as the change in kyphosis between lower-most instrumented vertebra (LIV) and LIV-2 from preop to postop (<-10). X2 analysis and post-hoc testing assessed annual and overall incidence of early (3M follow-u) and late (DJK development at 6M, 1Y, 2Y) DJK development among operative patients. Differences between early and late DJK (development after 3 months) were assessed. Pearson correlations determined significant variables associated with development of early versus late DJK. Severe DJK was defined as DJK angle <-20degree. DJK was considered symptomatic if associated with reoperation or the previously published thresholds of NDI>24 or mJOA<14. The natural progression of the disease was predicted with the use of a Kaplan-Meier survivorship analysis.
RESULT(S): A total of 139 patients without preop DJK were included (16 re-op) (61.8yrs, 62.3%F, 29.1kg/m2). Surgical characteristics: 20.1% anterior approach, 42.4% posterior, 36.7% combined (levels fused: 7.6). Incidence of DJK from 2013-2018: 23%. Early: 9.4%, late: 10.1% (6M delayed: 3.6%, 1Y delayed: 6.5%, 2Y delayed: 2.2%). No differences were observed between op and reop for development of early or late DJK at all f/u (p>0.050). Presence of upgoing plantar response at baseline neuro exam, C2-C7 angle, T1-C2 angle, CBVA and combined approach correlated with development of early DJK. For late DJK: history of tumor and pulmonary disease, pelvic incidence, T10-L2 angle, and L4 pelvic angle. Apex of the secondary driver was significantly lower in the Late group (mean early: T2/3; late: T10; p=0.023). 3M radiographically, Early DJK patients had greater TK (-57.9degree vs -40degree, p=0.024, while L4PA remained larger in the late DJK group (14.5degree, p=0.009). Between early and late groups, 41.7% of early DJK patients met criteria for severe DJK, while 0% of Late DJK patient were severe(p=0.010); symptomatic DJK between the two groups was not significant (p=0.941). Kaplan-Meier survivorship analysis determined patients within the cohort to have a 91.1% cumulative probability of maintaining non-DJK status by 3-month follow-up, 85.9% at 6-month, 80% at 1-year, and 77.0% by 2-year follow-up.
CONCLUSION(S): Patients undergoing CD corrective surgery have incidence of early and incidence of late DJK. While the majority of DJK development occurs within the first 6 months, late DJK occurs and differs in presentation and etiologic factors. Early DJK occurrence is more likely to be severe radiographically, associated with neurological decline, and is more strongly related to biomechanical factors such as use of a combined approach at the time of surgery. Contrarily, although equally likely to be symptomatic as reflected in loss of clinical gains from surgery, late DJK is more likely mild radiographically and associated with suboptimal cervical realignment and lack of addressing secondary drivers, likely related to negative compensatory mechanisms. Customized prophylactic approaches for both occurrences is mandated. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Amidst a current US opioid epidemic, it is important to understand factors that contribute to long-term or sustained opioid use after elective spine surgery. Recent reports have reported up to 25% of opioid-naive patients are taking opioids at 2-year follow-up after adult spinal deformity (ASD) surgery. This suggests ASD surgery, or at least the postoperative course, could be a significant factor contributing to long-term or sustained opioid use. ln Asian countries, opioids are rarely prescribed for postoperative pain. Potentially, there is a significant cultural difference that can play a role in patient expectations in the postoperative period leading to long-term opioid use. PURPOSE: To compare long-term or sustained (2-years) opioid use after ASD surgery between American and Japanese Cohorts STUDY DESIGN/SETTING: Propensity-matched comparison of American and Japanese ASD patients PATIENT SAMPLE: Patients from two (United States vs Japanese) prospective, multicenter ASD databases were compared OUTCOME MEASURES: Baseline and 2-year opioid use and SRS-22 domains were compared METHODS: We propensity matched 127 JPN to 619 US ASD patients based on age, sex, BMI, 3-column osteotomy, pelvic fixation, number of levels fused and preoperative SVA. Pre-op and 2-year postoperative opioid use was determined using responses to SRS22R Q11 and grouped into 3 categories (none, weekly, or daily). We have previously validated the use of SRS22R Q11 as an accurate measure for opioid use by comparing to a prospective study specifically designed to study opioid use and postoperative outcomes in ASD.
RESULT(S): From each cohort, 34 cases were successfully matched, with no difference in baseline parameters, including baseline opioid use (p=0.095), between the cohorts. The relatively low numbers in each cohort arise from difficulty matching a lower BMI and lower baseline opioid use in the JPN cohort. At 2-years postop, 22 US (65%) vs 31 JPN (91%) reported no opioid use, 1 US (3%) vs 0 JPN (0%) reported weekly use, and 11 US (32%) vs 3 JPN (9%) reported daily use (p=0.009). There was no difference in 2-year SRS-22 Self-image and Mental Health between the two groups while US patients had better Satisfaction (4.29 vs 3.84, p=0.032) but lower Function scores (3.52 vs 3.90, p=0.029).
CONCLUSION(S): In propensity-matched ASD cohorts, 35% of US patients were still using opioids 2 years after surgery compared to 9% of JPN patients, with the most taking opioids daily. Further studies are needed to identify sources of this variability. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Recombinant human bone morphogenetic protein 2 (BMP) is increasingly utilized in minimally invasive (MIS) transforaminal lumbar interbody fusions (TLIF) in order to increase rate of fusion by promoting bone growth through the induction of osteoblast differentiation, awhile reducing morbidity related to iliac crest autograft. Despite these benefits, BMP use is still controversial due to its pro-inflammatory mechanism of action and potential to cause radiculitis. PURPOSE: To assess whether BMP is a risk factor for postoperative radiculitis in TLIF. STUDY DESIGN/SETTING: Single-center retrospective cohort study. PATIENT SAMPLE: A total of 397 TLIFs from June 2012 to December 2018. OUTCOME MEASURES: Perioperative clinical characteristics, post-operative risk of radiculitis and complication, and future reoperation rates.
METHOD(S): Patients >= 18 years-old undergoing elective single-level TLIFs from 2012 to 2018 were included. Outcome measures included perioperative clinical characteristics, postoperative risk of radiculitis and complication, and future reoperation rates. Radiculitis was defined the delayed onset of radicular symptoms postoperatively in patients whom had initial resolution of radicular symptoms immediately postoperatively, in the absence of persistent neurological compression on postoperative imaging. Statistical analyses included independent t-tests and chi-square analysis. Propensity score matching was utilized to control for demographic differences between the groups. Independent predictors for post-operative radiculitis were assessed by multivariate logistic regression. Significance set at p<0.05.
RESULT(S): A total of 397 cases were included in the study (59.33 +/- 13.49 mean age, 28.98 +/- 6.29 mean BMI, 52.90% female, 2.29 +/- 1.92 average Charleston comorbidity Index). There were 223 open procedures and 174 MIS. For the entire cohort, 238 cases utilized BMP and 159 did not, with 102 MIS pairing with BMP use. The MIS TLIFs had a higher percentage of BMP use than open TLIFs (58.6% vs 25.7%, p<0.001), lower estimated blood loss (212.28 +/- 193.79 mL vs 410.91 +/- 337.98 mL, p<0.001) higher fluoroscopy dosage (52.43 +/- 48.61mGy vs 16.77 +/- 27.84mGy, p<0.001), and a lower length of stay (3.20 +/- 2.55 days vs 4.11 +/- 2.52 days, p<0.001). There were no other differences in perioperative clinical characteristics. There was a significantly higher rate of postoperative radiculitis in the MIS TLIFs compared to open (12.6% vs 6.8%, p=0.046) and use of BMP compared to no BMP (13.2% vs 6.7%, p=0.029). There was a 15.7% radiculitis rate when MIS was paired with BMP use. There were no other notable differences in complication rates or rates of reoperation. Individually, MIS had a 12.6% radiculitis rate (p=0.046) and BMP use had a 13.2% rate (p=0.029). Propensity score match controlled for the significant difference in CCI between the MIS and open groups (N=168 each). Multivariate regression indicated that MIS (p=0.314) and BMP (p=0.109) were not independent predictors individually when controlling for age, gender, and BMI. When technique was paired with biologic use the regression revealed MIS + BMP is a risk factor of post-operative radiculitis (2.265(4.753-1.079), p=0.031).
CONCLUSION(S): While BMP and MIS technique were not independent risk factors for postoperative radiculitis, there is an increased risk of radiculitis when using BMP in MIS TLIF. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Prior studies have demonstrated potential benefits of adult spinal deformity (ASD) surgery, but less outcomes data exist for operative ASD patients with severe scoliotic curves (thoracic [TH] curve >=75degree, thoracolumbar [TL] curve >=50degree, or lumbar [LL] curve >=50degree). Also, the surgical complication profile is less clear for this subset of patients with severe scoliotic deformity and warrants focused investigation. PURPOSE: The objective of the current study was to assess treatment outcomes and complication rates associated with ASD surgery in patients with severe scoliosis. STUDY DESIGN/SETTING: Retrospective review of a prospectively collected multicenter consecutive case registry PATIENT SAMPLE: Enrollment required: age >=18 yrs, scoliosis >=20degree, sagittal vertical axis (SVA) >=5cm, pelvic tilt >=25degree, and/or thoracic kyphosis >=60degree. OUTCOME MEASURES: Standard coronal and sagittal spinopelvic deformity measurements and health-related quality of life (HRQL) outcomes, which included Oswestry Disability Index (ODI), Short Form-36 (SF-36) scores, and Scoliosis Research Society-22 (SRS-22) scores.
METHOD(S): Using a prospective multicenter database, we identified surgically treated ASD patients with severe scoliosis (TH Cobb >=75degree or TL/LL Cobb >=50degree) and minimum 2-yr follow-up. Demographic data, surgical characteristics, radiographic alignment measurements, HRQL outcomes and associated complications were analyzed.
RESULT(S): Of 178 patients, 146 (82%, mean age 54 yrs, 92% women, 88 TL, 50 LL, 8 TH) had minimum 2-yr follow-up (mean=3.1 yrs). Almost 30% had prior spine fusion, 6% were active or past smokers, 16% had osteoporosis and 77% had at least 1 comorbidity. Surgical details included: posterior-only (58%) or anterior-posterior approach (42%), SPO (65%), 3CO (14%), TLIF (23%), ALIF (37%), sacropelvic fixation (76%), upper thoracic UIV (64%) and mean posterior fusion length of 13.2 levels. Postoperative coronal alignment improved significantly for all patients (global coronal alignment 3.8 to 2.8 cm, p< 0.001; TH Cobb 38degree to 24degree, p<0.001; TL Cobb 61degree to 30degree, p<0.001; LL Cobb 50degree to 24degree, p<0.001; Fractional Cobb 20degree to 7degree, p<0.001). Overall sagittal alignment also improved significantly (p<0.05), most notably for severe lumbar curves (C7-S1 SVA 6.7 to 2.5 cm, p<0.001; PI-LL 18degreeto 3degree, p<0.001). Overall HRQL improved significantly, including ODI (39 to 26, p<0.001), SF-36 PCS (35 to 41, p<0.001) and SRS-22r (2.9 to 3.8, p<0.001). A total of 191 complications were reported (92 minor/99 major), and 94 (64%) patients had at least one complication. The most common complications included dural tear (12%), pleural effusion (12%), rod fracture (11%), radiculopathy (8%) and proximal junctional kyphosis (7%). 34 reoperations were performed in 27 (18%) patients, with most common indications of rod fracture/pseudarthrosis (8), deep wound infection (6) and neurological deficit (5).
CONCLUSION(S): Surgery for severe adult scoliosis is associated with significant improvement in radiographic alignment and HRQL measures. Although associated complication rates are high, these appear to be comparable to reports of less severe scoliosis. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Age and pelvic incidence (PI) optimal alignment has been shown to minimize mechanical complications such as PJK. Low PI patients may be susceptible to overcorrection because PI specific alignment is not always prioritized. PURPOSE: The purpose of this study is to examine the incidence of over-correction in low PI ASD patients undergoing surgical intervention, and to quantify the impact of over-correction on radiographic PJK in this patient population. STUDY DESIGN/SETTING: Retrospective analysis of a prospective, multicenter database. PATIENT SAMPLE: Surgical ASD patients with low pelvic incidence. OUTCOME MEASURES: PJK defined as 1) proximal junctional angle (PJA, U

BACKGROUND CONTEXT: Operative treatment of adult spinal deformity (ASD) can be very challenging with high complication rates. Despite these challenges it's well established that pts benefit from such treatment. However, the surgical outcomes for pts with mild scoliosis and age appropriate sagittal alignment have not been reported. PURPOSE: To determine if patients (pts) with mild scoliosis and age appropriate sagittal alignment have favorable outcomes following surgical correction. STUDY DESIGN/SETTING: Retrospective review of a prospective, multicenter ASD database. PATIENT SAMPLE: ASD patients: operative pts age>=18, and all preoperartive pelvic tilt (PT), mismatch between pelvic incidence and lumbar lordosis (PI-LL), and C7 sagittal vertical axis (SVA) within established age adjusted parameters with minimum 2-year follow up. A subanalysis for pts with max coronal cobb angle 10-30degree (mild scoli) was done. OUTCOME MEASURES: Health-related quality of life (HRQOL) scores: Oswestry Disability Index (ODI), Short form-36(SF36), Scoliosis Research Society (SRS22), back/leg pain numerical rating scale (NRS) and minimum clinically important difference (MCID)/substantial clinical benefit (SCB). Radiographic values: max coronal cobb angle, coronal C7 plumb line, PT, PI-LL, thoracic kyphosis (TK), SVA. Demographic, frailty, surgical and complications data were collected.
METHOD(S): Two-year and baseline HRQOL/radiographic data were compared.
RESULT(S): A total of 103 pts were included from 667 operative patients (89.3% female, avg age 59.8+/-13.1yrs). Of the 103 pts, 29 (28.2%) had max preop coronal cobb angle 10-30degree. Two-year max coronal cobb angle and C7 coronal plumb were significantly improved compared to baseline (p<0.001 for both the overall cohort and mild scoli). All 2yr HRQOL measures were significantly improved compared to baseline(p<0.001) for both groups. 33.3-81.5%% of mild scoli pts met either MCID/SCB for all HRQOL. In mild scoli pts, 62.1% had min one complication, 27.6% had a major complication with 24.1% requiring a revision.
CONCLUSION(S): Pts with mild scoliosis and sagittal alignment within age appropriate parameters benefit from surgical correction at 2 years postop both radiographically and clinically including 81.5% meeting MCID for SRS pain despite having high complication rates. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Frailty is an increasingly recognized characteristic that has been validated across many studies as influencing operative risk. Utilization of frailty indices can allow for its identification of which spine patients may be too high risk for surgical intervention. This may be especially useful when it comes to surgeries that are minimally invasive and are supposed to have decrease perioperative outcomes. PURPOSE: Identify MIS techniques effects in postoperative outcomes in TLIF patients. STUDY DESIGN/SETTING: Retrospective review of a prospective database. PATIENT SAMPLE: TLIF spine patients. OUTCOME MEASURES: Complications, length of stay (LOS), estimated blood loss (EBL).
METHOD(S): Pts that underwent a lumbar spine procedure in a single-center Comprehensive Spine Quality Database. Pts were stratified based on procedural approach (Open [OP] and Minimally invasive Surgery [MIS]). Frailty was then calculated for each resultant group by using 30 variables with a validated method. Based on these scores, pts were categorized no frailty [NF]: <0.09, frail [F]: 0.09-0.18, and severe frailty [SF] >0.18. Groups were then controlled for surgical invasiveness. Chi-squared tests identified the relationship between complications and length of stay among various frailty states given surgical approach (OP vs MIS). These patients were propensity score matched for levels fused. Hospital acquired complications (HACs) were identified based on frailty groups through the use of chi-squared and t-tests for other surgical factors. A logistic regression analysis identified the association between frailty status and surgical, regarding postoperative (postop) outcomes.
RESULT(S): A total of 1,300 TLIF spine patients were isolated (59yrs, 29.3kg/m2). After PSM for levels fused, there were 338 pts for both MIS and OP. MIS pts were older (56.1 vs 53.3; p<0.05) than Op pts and had similar BMI's (29.1 vs 29.7; respectively). However, OP received more posterior approaches and less anterior approaches than MIS pts (p<0.05). By surgical factors: MIS and OP patients had similar LOS (3 vs 2.9days) and EBL (282.8 vs 251.5cc) but differed by Op time (195.7 vs 247.1; p<0.05) respectively. Further breakdown by frailty displayed statistical significance between MIS and OP patients with MIS pts having more F (16% vs 12%) and SF pts (4.3% vs 1.9%) than OP (all p<0.05). FMIS patients had lower postop neurologic complications as compared to FOP pts (4.63% vs 14.8%). However, SFMIS patiens had more post-operative complications than SFOP pts (55.2% vs 23.1%) and increased a pt's likelihood of being SFMIS by 5.4x's (all p<0.05).
CONCLUSION(S): This study displays that when frailty status is taken into account, TLIF MIS patients benefit from this procedure type when analyzed against neurologic complications. However, these patients were seen to suffer more from postop complications but did not differ on any other specific complications or surgical variables. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Substantial adult spinal deformity (ASD) research has focused on sagittal plane radiological assessment and emphasized the importance of sagittal correction on patient-reported outcomes. It seems less attention has been given to evaluation of ASD in the coronal plane. However, recent ASD studies have demonstrated baseline global coronal malalignment (GCM; substantial displacement of the C7 coronal plumb line from midsacrum) in up to 35% of patients. Moreover, GCM can worsen postoperatively or may occur as an iatrogenic complication in previously balanced patients. Collectively, this may suggest that the associated clinical impact of GCM on ASD surgical outcomes has been underestimated. Currently, few reports focus on surgical outcomes in ASD patients with GCM. PURPOSE: Our objective was to assess treatment outcomes and complication rates associated with ASD surgery in the subset of patients with severe GCM. STUDY DESIGN/SETTING: Retrospective review of a prospectively collected multicenter consecutive case registry. PATIENT SAMPLE: Enrollment required: age >=18 years, scoliosis >=20degree, sagittal vertical axis (SVA) >=5cm, pelvic tilt >=25degree, and/or thoracic kyphosis >=60degree. OUTCOME MEASURES: Radiographic correction (both standard coronal and sagittal spinopelvic deformity measurements) and health-related quality of life (HRQL) outcomes, which included Oswestry Disability Index (ODI), Short Form-36 (SF-36) scores, Scoliosis Research Society-22 (SRS-22) scores, and back/leg pain numerical rating scale (NRS) scores.
METHOD(S): Surgically treated ASD patients with severe GCM (coronal C7PL-midsacral offset magnitude >=1 SD above the mean) were identified. Baseline and follow-up radiographic and HRQL outcomes were analyzed. Percentages of patients achieving minimal clinically important difference (MCID) and substantial clinical benefit (SCB) were assessed. Demographic, frailty, surgical, and complications data were collected. The primary focus for analysis was on patients who reached minimum 2-year follow-up.
RESULT(S): Of 691 potentially eligible operative patients (mean GCM = 4+/-3 cm), 80 met criteria for severe GCM >= 7cm. Of these 80 patients, 62 (78%, mean age 64 years, 81% women) had minimum 2-year follow-up. Baseline frailty score was 3.9+/-1.5 (indicating patients were frail) and 48% had prior spine fusion. Surgical data included: posterior-only (58%), mean fusion 13 levels, sacroiliac fixation (97%), and three-column osteotomy (36%). Postoperative biplane alignment improved significantly (p<0.001): GCM 11 to 4 cm, lumbar Cobb 30degree to 11degree, C7-S1 SVA 13 to 4 cm, and PI-LL 31degree to 5degree. Overall HRQL improved significantly (p<=0.003): ODI 51 to 37, SF-36 PCS 29 to 37, SRS-22r 2.6 to 3.5, and back/leg pain NRS 7 to 4 and 5 to 3, respectively. Thresholds for MCID/SCB were met in 43-83% of patients. A total of 89 complications were reported (34 minor/55 major), and 45 (73%) patients had >=1 complication (most commonly rod fracture [19%] and PJK [18%]). There were 34 reoperations in 22 (36%) patients (most common indications rod fracture/PJK). The 18 patients who did not achieve 2-year follow-up had a mean of 0.63 years follow-up, and the types of complications encountered in these 18 patients were comparable to those encountered in patients with 2-year follow-up.
CONCLUSION(S): ASD surgery for patients with severe GCM is associated with significant improvements in biplane alignment and HRQL outcome measures despite high complication rates. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Thoracolumbar malalignment is often seen in patients presenting with cervical deformities. For operative cervical deformity (CD) patients, it is unknown whether certain thoracolumbar parameters play a large role in poor outcomes (complications, distal junctional kyphosis, reoperation) and whether addressment of such parameters is warranted. PURPOSE: To investigate the impact of cervical to thoracolumbar ratios on poor outcomes in CD corrective surgery. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: 110 CD patients. OUTCOME MEASURES: Radiographic parameters: regionally and globally; complications; distal junctional kyphosis (DJK); reoperations; health-related quality-of-life (HRQLs): NDI, EQ5D, mJOA.
METHOD(S): Included: surgical CD pts (C2-C7 Cobb >10degree, CL>10degree, cSVA >4cm, or CBVA >25degree) with full baseline and 1-year data. Patients were assessed for ratios of preop cervical and global parameters including: C2 slope/T1 slope, TS-CL/PI-LL, cSVA/SVA. Deformity classification ratios of cervical (Ames-ISSG) to spinopelvic (SRS-Schwab) were investigated: cSVA modifier/SVA modifier, TS-CL modifier/PI-LL modifier. Cervical to thoracic ratios included C2-C7 lordosis/T4-T12 kyphosis. Correlations assessed the relationship between ratios and poor outcome (major complication, reoperation, HRQL decline or failure to meet MCID). Decision tree analysis through multiple iterations of multivariate regressions assessed cut-offs for ratios for acquiring suboptimal outcomes.
RESULT(S): A total of 110 cervical deformity patients were included in the present analysis (61.5+/-9.9 years, 66% female, 28.8+/-7.5 kg/m2). By approach, 18.2% underwent anterior-only procedures, 46.4% posterior, and 35.4% combined. Average levels fused: 7.7+/-3.7 levels (anterior: 3.5, posterior: 8.5). The average preoperative radiographic ratios assessed included a C2 slope/T1 slope 1.56, TS-CL/PI-LL of 11.1, cSVA/SVA of 5.4, CL/TK of 0.26. Ames-ISSG and SRS-Schwab modifier ratios of cSVA/SVA 0.1 and TS-CL/PI-LL of 0.35. Pearson correlations demonstrated a significant relationship between major complications and the baseline TS-CL/PI-LL with a cutoff of >12.72 (p=0.034), >0.482 Ames TS-CL/Schwab PI-LL modifiers (p=0.019), and the CL/TK ratios (>0.814, p=0.050). Reoperation had a significant correlation with the TS-CL/PI-LL (>5.819, p=0.009) and the cSVA/SVA (>3.79, p=0.002) ratios. Postoperative DJK had a correlation with the C2 slope/T1 slope (>1.59, p=0.017) and CL/TK (>0.692, p=0.0629) ratios. Not meeting MCID for NDI correlated with the CL/TK ratio (>1.402, p=0.016) and not meeting MCID for EQ5D correlated with the Ames TS-CL/Schwab PI-LL (>0.564, p=0.010).
CONCLUSION(S): Consideration of the ratio of distal regional to global alignment is a critical determinant of outcomes in cervical deformity corrective surgery. Several key ratios of cervical to global alignment were found to correlate with the occurrence of suboptimal realignment parameters, or poor clinical outcomes. A larger cervical lordosis to thoracic kyphosis was most representative of this risk, which predicted a complication, DJK, and not meeting MCID for NDI. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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