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Background/UNASSIGNED:Changes in spinopelvic and lower extremity alignment between standing and relaxed sitting have important clinical implications with regard to stability of total hip arthroplasty. This study aimed to analyze the effect of body mass index (BMI) on lumbopelvic alignment and motion at the hip joint. Methods/UNASSIGNED:A retrospective review of patients who underwent full-body stereoradiographs in standing and relaxed sitting for total hip arthroplasty planning was conducted. Spinopelvic parameters measured included spinopelvic tilt (SPT), pelvic incidence (PI), lumbar lordosis (LL), PI minus LL (PI-LL), proximal femoral shaft angle (PFSA), and standing-to-sitting hip range of motion. Propensity score matching controlled for age, gender, PI, and hip ostoarthritis grade. Patients were stratified into normal (NORMAL; BMI, 18.5-24.9), overweight (OW; 25.0-29.9), and obese (OB; 30.0-34.9) groups. Alignment parameters were compared using one-way analysis of variance. Results/UNASSIGNED:< .001). Conclusions/UNASSIGNED:Significant differences in sitting and standing-to-sitting change in lumbopelvic alignment based on BMI suggest obese patients recruit more posterior spinopelvic tilt when sitting to compensate for soft-tissue impingement that occurs anterior to the hip joint and limiting hip flexion.

BACKGROUND CONTEXT: Expandable cages (EXP) are more frequently utilized in Transforaminal Lumbar Interbody Fusions (TLIF). Designed to reduce complications related to neurological retraction, enable better lordosis restoration, and improve ease of insertion, particularly in the advent of minimally invasive techniques they are exponentially more expensive than the non-expandable (NE) alternate. PURPOSE: To investigate the value of expandable cages given the significantly higher cost. STUDY DESIGN/SETTING: Retrospective review at a single institution. PATIENT SAMPLE: A total of 257 TLIFs between 2012 and 2018 were included. OUTCOME MEASURES: Clinical characteristics, perioperative and neurologic complication rates and radiographic measures.
METHOD(S): Patients >= 18 years of age who underwent single-level TLIF with minimum 1-year follow-up were included. Outcome measures: clinical characteristics, perioperative complications and neurologic complications. Radiographic analysis included change in pelvic incidence-lumbar lordosis (PI-LL), segmental lumbar lordosis (LL), and disc height restoration. Subsidence was radiographically assessed at 1-year follow-up from intraoperative imaging for breaching of the vertebral endplates, measured from the cage endplate to vertebral endplate and defined as a >2mm. Statistical analysis included independent t-tests and chi-square analysis with significance set at p<0.05.
RESULT(S): A total of 257 TLIFs between 2012 and 2018 were included, with 155 NE (53.5% female, mean age 59.46+/-14.07, mean BMI 28.69+/-5.39) and 102 EXP (49% female, mean age 57.78+/-11.76, mean BMI 28.72+/-6.01) with no significant differences in demographics. There were significantly more MIS TLIF cases and BMP use in the EXP group (88.2% MIS, p<0.001 and 59.8% BMP, p<0.001). When controlling for proportion of MIS cases, EXP had a lower operative time and estimated blood loss respectively (215.74+/-59.53 min, p=0.015; 194.72 +/- 187.19 mL, p=0.028). There were no other significant differences in clinical outcomes due to the instrumentation, though there were limited numbers (N=132: 90 EXP vs 42 NE). There were no significant differences between the EXP and NE groups in postoperative rates of radiculitis (14.4% vs 9.5%, p=0.462), and neuropraxia (7.8% vs 7.1%, p=0.750). Radiographic analyses demonstrated no significant differences with respect to change in baseline to 1-year follow-up between groups. No significant difference in post-operative subsidence was observed between the EXP and NE from intraoperative to 1-year follow-up (28.9% vs 28.6%, p=0.970).
CONCLUSION(S): Once technique was controlled for, TLIFs utilizing EXP do not have significantly different neurologic or radiographic outcomes compared to NE. These results question the value of EXP given the higher cost. The findings require further direct comparison in the MIS population because the benefit on outcomes compared to the alternate remains controversial due to the bias towards increased use in MIS procedures. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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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: Recombinant human bone morphogenetic protein 2 (rhBMP-2) is a popular biologic product used in transforaminal lumbar interbody fusion (TLIF) surgeries to promote fusion and avoid the morbidity associated with iliac crest autograft. However, use of rhBMP-2 and its effect on pseudarthrosis rates in TLIFs remains unknown. PURPOSE: To assess the rates of pseudarthrosis in open and MIS TLIF patients, with and without concurrent rhBMP-2 use. STUDY DESIGN/SETTING: Retrospective cohort study at a single academic institution. PATIENT SAMPLE: Included: 317 single level TLIF patients. Consisting of 157 open TLIF (OTLIF), 115 bilateral Wiltse MIS TLIF (WTLIF), and 45 hybrid midline MIS with percutaneous pedicle or cortical screws (MTLIF). OUTCOME MEASURES: Clinical characteristics, perioperative and postoperative outcomes, surgical procedure, rates of pseudarthrosis diagnosis, and revision for pseudarthrosis.
METHOD(S): Patients >=18 years old undergoing 1-level TLIF with minimum 1-year of clinical and radiographic follow up were included. Pseudarthrosis was determined using both radiographic and clinical evaluations. Differences between groups were assessed by ANOVA and chi squared analyses. Demographic and perioperative characteristics were analyzed by multivariate logistic regression.
RESULT(S): The cohort included 317 patients (mean age 59.68+/-13.29, F 52.7%). There was no significant difference in gender, BMI, or smoking status among groups (all p>.05). WTLIF had the lowest EBL (ml) (192.16+/-177.11mL vs 302.73+/-246.51 vs 363.85+/-370.49, respectively p=<0.001) and LOS (days) (2.88+/-1.76 vs 4.16+/-3.94 vs 4.03+/-1.97, respectively p=<0.001) compared to MTLIF and OTLIF. Further, MTLIF had the highest fluoroscopic dose (mGy) compared to WTLIF and OTLIF (52.85+/-40.49 vs 52.80+/-52.77 vs 15.21 +/- 24.53, respectively p=<0.001). MTLIF was also associated with the lowest BMP use compared to OTLIF and MTLIF (13.3% vs 23.6% vs 67.8%, respectively p=<.001). At minimum 1-year follow-up, there was no significant difference between the three different approaches with regards to pseudarthrosis rates (WTLIF 6.1%, MTLIF 8.9%, OTLIF 3.2%, p=0.249) or returns to the OR for pseudarthrosis (WTLIF 3.5%, MTLIF 6.7%, OTLIF 3.2%, p=0.546). Pseudarthrosis rates in patients treated with BMP was 5% (p = 0.881) for the cohort. There was no difference in reoperation for pseudarthrosis between patients who received BMP (2.5%) versus those who did not receive BMP (4.6%, P = 0.338). Multivariate Logistic regression analysis demonstrated no reduction in pseudarthosis related to BMP use (Odds Ratio 1.07 [CI 95% 0.228-5.04], p=0.929). Current or past smoking did not have an effect on use of BMP (p = 0.369) or significantly increase the rate of pseudarthrosis (p = 0.214), regardless of BMP use.
CONCLUSION(S): MP use did not reduce the rate of pseudarthrosis or the number of reoperations for pseudarthrosis in this cohort. No difference in pseudarthrosis rates between the three TLIF approaches was noted. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: C5 palsy stands as a known but poorly understood complication of cervical spine surgery with rates reported as high as 30%. Although there are multiple studies presenting different risk factors, variability in findings have led to controversy in the etiology of postoperative C5 palsy. PURPOSE: To evaluate factors that predispose a patient to developing C5 palsy following cervical spine surgery. STUDY DESIGN/SETTING: Retrospective review of a large single center academic institution. PATIENT SAMPLE: This study included 239 cervical spinal procedures from 2013 to 2018. OUTCOME MEASURES: Patient demographics, surgical procedure and approach, perioperative clinical characteristics, postoperative rate of C5 palsy, C5 palsy resolution, and radiographic outcomes.
METHOD(S): Patients >=18 years of age who underwent cervical spinal surgery including the C4/C5 level, with minimum 1-year follow-up were included. C5 palsy was defined as deltoid +/- bicep weakness with Modified Rankin Scale grading at least 1 point below baseline (BL). Characteristics studied include: demographics, surgical procedure and approach (decompression and/or fusion). Radiographic analyses of MRI and CT measurements of foramen dimensions and spinal cord drift at BL and follow-up were performed. Statistical analyses included t-tests, chi-square analysis, and multivariate logistic regression to determine independent predictive factors. A receiver operating characteristic curve was run to determine the cutoff levels for predictive factors. Significance set at p<0.05.
RESULT(S): A total of 239 patients were included, with a C5 palsy rate of 6.3% for all cases. Subjects that developed C5 palsy were older (64.67+/-8.61 vs 57.56+/-11.61, p=0.021), had more levels decompressed posteriorly (3.20+/-1.82 vs 1.12+/-1.74, p<0.001), a higher rate of preoperative myelomalacia (60% vs 19.6%, p=0.008), and higher CCI (3.80+/-1.97 vs 2.35+/-1.95, p=0.005). Anterior cervical discectomy and fusion (ACDF) surgeries had a 2.4% rate of C5 palsy while the posterior approach rate was 11.9% (p<0.007). The highest rate was in laminectomy and posterior fusion at 15.2% (p<0.001). There were no significant differences in palsy resolution between those treated surgically compared to those not treated. Radiographically, C5 palsy patients had smaller postoperative foramen width measurements than those who did not develop C5 palsy (2.16+/-1.04 vs 3.31+/-1.25, p=0.023 on the right; 1.84+/-0.80 vs 3.02+/-1.25, p=0.014 on the left). When controlling for technique, CCI, age, BMI, and myelomalacia, multivariate regression analysis revealed increasing levels of laminectomy to be a significant independent predictor of C5 palsy (1.602 (2.258-1.136) for each additional level decompressed, p=0.007). The cut-off value for levels decompressed via laminectomy was determined to be 3.50 levels (>=0.7 AUC <=0.8). Postoperative foramen width was also an independent risk factor for C5 palsy (0.009 (0.000-0.726), p=0.035), it was determined that risk of C5 palsy increases at <2.625mm foramen width (>=0.8 AUC <=0.9).
CONCLUSION(S): C5 palsy following cervical spine surgery is correlated with residual postoperative foraminal stenosis and posterior surgery with increasing number levels decompressed. Patients undergoing more than 3.5 level laminectomy with less than 2.625mm foramen width postoperatively are at highest risk of developing C5 palsy. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The Patient Reported Outcome Measurement Information System (PROMIS) aims to offer a valid, reliable and efficient means of capturing spine surgery patient clinical outcomes. To date, few studies have compared PROMIS and legacy outcome measures like the Oswestry Disability Index (ODI) for their sensitivity in reflecting the impact of perioperative complications and length of stay. PURPOSE: Assess differences between PROMIS and ODI scores as they relate to length of stay and complication outcomes of surgical thoracolumbar patients. STUDY DESIGN/SETTING: Retrospective review of single institution clinical data and patient-reported outcome measures. PATIENT SAMPLE: A total of 182 patients undergoing thoracolumbar surgery. OUTCOME MEASURES: Length of stay (LOS), perioperative complications.
METHOD(S): Patients >18 years undergoing thoracolumbar surgery with available pre- and 3-month postoperative ODI and PROMIS scores were included. Pearson bivariate correlation assessed the linear relationships between clinical outcomes (including length of stay, complications) and scores for both PROMIS (Physical Function, Pain Intensity, Pain Interference) and ODI. Linear regression predicted the relationship between perioperative complication incidence and postop scores for ODI and PROMIS. Significance was set p<0.05.
RESULT(S): Included: 182 patients (55.2+/-16.1 years, 44.5% female, 29.5+/-6.3 kg/m2) undergoing thoracolumbar surgery. Among the most common diagnoses were stenosis (62.1%), radiculopathy (48.9%), herniated disc (47.8%), and degenerative spondylolisthesis (25.3%). Overall, 58.3% of patients underwent fusion (mean fusion length: 2.6+/-2.9 levels), 50% underwent laminectomy, 82.9% of cases involved posterior-only approach, 17.6% combined, and 0.5% anterior-only. Patients showed significant pre- to postoperative improvement in both ODI (50.2 to 39.0) and PROMIS Physical Function (10.9 to 21.4), Pain Intensity (92.4 to 78.3) and Pain Interference (58.4 to 49.8, all p<0.001). Mean LOS was 2.7+/-2.8 days. The overall complication rate was 16.5%, and by type, complications were most commonly cardiac, neurologic, or urinary (all 2.2%). Whereas LOS showed no relationship with pre- to postop changes in ODI (p=0.179), changes in PROMIS Pain Intensity (r=0.167, p=0.024) and Physical Function (r=-0.169) both correlated with LOS. Complication occurrence was not correlated with pre- to postoperative changes in ODI or PROMIS (all p>0.05); however, 3-month postoperative scores for Physical Function (r=-0.205, p=0.005) and Pain Interference (r=0.182, p=0.014) both showed stronger correlations with complication occurrence than ODI (r=0.143, p=0.055). Regression analysis showed that while perioperative complication incidence could not predict postoperative ODI (p>0.05), complication occurrence predicted Physical Function (R2=0.037, p=0.005) and Pain Interference (R2=0.028, p=0.014) scores.
CONCLUSION(S): The PROMIS domains of Physical Function and Pain Interference better reflected perioperative complications and length of stay as compared to the legacy patient reported outcome ODI. These results suggest PROMIS may offer more utility as an outcomes assessment instrument. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Screw placement in transforaminal interbody fusion (TLIF) and anterior lumbar interbody fusion (ALIF) can be done with open free hand (FH), fluoroscopy-guided (FG), spinal navigation (NAV), or robotic guided (RG) techniques. Varied techniques may affect perioperative (periop) outcomes. Few studies compare all four guidance techniques. PURPOSE: Compare the perioperative outcomes between FH, FG, NAV, and RG TLIF and ALIF. STUDY DESIGN/SETTING: Single center retrospective cohort study PATIENT SAMPLE: A total of 1,646 patients who underwent 1-2 level TLIF or 1-3 level ALIF from 2012-2019. OUTCOME MEASURES: Outcomes: registration failure, operative time (OT), radiation dosage (RD), estimated blood loss (EBL), length of stay (LOS), and periop complications, and retursn to OR up to 90 days.
METHOD(S): Patients undergoing 1-2 level TLIF or 1-3 level ALIF were included. Analysis of variance (ANOVA) and chi2test were used to analyze differences in outcomes with significance set at p<0.05. Post hoc Tukey (PHT) and Bonferroni (PHB) analysis were conducted when ANOVA or chi2 showed significance. RD was propensity matched for BMI. TLIFs underwent PSM for levels fused.
RESULT(S): A total of 1,202 1-2 level TLIFs were included (843 FH, 175 FG, 40 NAV, 144 RG) TLIFS. 444 1-3 level ALIFs were included: 337 FH, 25 FG, and 80 RG ALIFs. Demographics were similar amongst ALIF cohorts except significantly more FH-ALIF smokers and TLIF cohorts after propensity matching for levels fused. Amongst the TLIF Cohorts: OT and LOS longest in NAV (291.67+/-89.85 min; p <0.001 and 5.38+/-1.66 days p<0.001); EBL most in FG (482.43+/-530.79mL p=0.006). After PSM for BMI, there was no significant difference in RD. RG TLIF registration failed in 2.8% of cases. There were significantly more intraop (11.1%, p=0.008), and postop (45.8%; p<0.001) complications in the RG cohort, which showed high durotomy rates (6.9%; p=0.05) and instrumentation failure rates approaching significance (3.5%; p=0.058). The NAV group had the highest rate of SSI (2.5%; p = 0.045). Among the ALIF cohorts: RD, EBL, and LOS were similar; OT was longest in FG (395.7+/-113.7 p=0.001). There were significantly more intra- and postop complications in RG group (26.3%, p<0.001; 30%, p<0.001) and 13.8% of RG failed registration. Instrumentation failure was highest in FG (4.0% p=0.676), along with return to OR for instrumentation (8%, p = 0.183). Other periop complications and returns to OR were not significantly different.
CONCLUSION(S): NAV-TLIF had significantly differences in EBL, RD, periop complications, and return to OR 30 days. PSM for levels fused show postop complications rate remain significant with other factors and radiographic dosage remaining significant. RG TLIF and RG ALIF had the worst perioperative complications. 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: Hyperlordotic (>20degree) anterior interbody cages (HAI) may be utilized in anterior-posterior fusion (AP-F) in efforts to improve alignment. However, significant increase in segmental lordosis (SL) in HAI without superior articulating process resection (SAP) may result in foraminal stenosis and nerve root compression causing neurological deficits and radiculopathy. Additionally, HAI with SAP may increase SL without concomitant increase in lumbar lordosis (LL). PURPOSE: Assess whether HAI without SAP in APF causes increased neurological complications. STUDY DESIGN/SETTING: Single-center retrospective cohort study PATIENT SAMPLE: A total of 158 patients undergoing single level APF were included, of which 73 had HAI placed and 85 had SAI placed. OUTCOME MEASURES: Outcomes measures included radiographic analysis of pre- and postoperative LL and SL. Perioperative neurological complications were measured including new radiculopathy, iatrogenic motor deficit and malpositioned instrumentation or compressive hematoma causing deficit. Returns to OR within 30 or 90 days were measured including return for foraminal decompression, instrumentation revision, hematoma evacuation, and irrigation and debridement.
METHOD(S): Patients undergoing primary, single level, APF without SAP resection over a 5-year period were included. Patients were classified as HAI or SAI. Outcomes measures included perioperative neurological complications, returns to OR, pre- and postoperative LL and SL. Demographic, procedural and perioperative outcomes were compared using independent samples t-tests and chi-squared analyses as appropriate with significance set at p<0.05. Risk factors for development of neurological complications were assessed with multivariate logistic regression.
RESULT(S): A total of 158 patients (73 HAI, 85 SAI) were included. Age, gender, BMI and CCI were similar between groups. HAI without SAP resulted in significantly larger change in SL (9.84+/-5.84 vs 7.32+/-5.02 deg, p=0.001), without a significantly larger change in LL (8.16+/-1.11 vs 11.5+/-1.69 deg; p=0.641) compared with SAI. HAI without SAP increased overall incidence of neurological deficit (13.69% vs 3.53%; p=0.012), iatrogenic new cases of radiculopathy (10.95% vs 3.53%; p=0.045), and iatrogenic neurological motor deficit (13.69% vs 3.53%; p=0.012). Regression analysis demonstrated that increasing cage lordosis greater than 20degree is an independent risk factor for neurological complications (p=0.046), as is higher preop SL (p=0.022). There were no significant differences in returns to OR.
CONCLUSION(S): We caution HAI implantation without SAP resection due to increased neurological complications from iatrogenic nerve root injury without the benefit of significantly improving LL correction. Use of HAI without SAP resection in single level APF should not be standard practice due to risk of neurological complications. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Frailty is a baseline measure of disability that transcends age alone and has been determined a strong predictor of outcomes following adult spinal deformity (ASD) surgery. This postop impact calls for investigation of unique adjustment of Global Alignment and Proportion (GAP) scores accounting for frailty. This adjustment in spinal proportion may help surgical planning for individualized, optimal postop outcomes. PURPOSE: Modify the GAP score with frailty to optimize outcomes in surgical ASD patients. STUDY DESIGN/SETTING: Retrospective review of a single-surgeon comprehensive ASD database PATIENT SAMPLE: A total of 140 ASD patients OUTCOME MEASURES: Frailty-adjusted GAP scores; Health Related Quality of Life scores (HRQLs): ODI, SRS-22 METHODS: Surgical ASD patients (SVA>=5cm, PT>=25degree, or TK >=60degree, >3 levels fused) >=18 years old with available baseline (BL) radiographic data were isolated in the single-center Comprehensive Spine Quality Database (Quality). Patients were dichotomized by the ASD frailty index, F (Not Frail, Frail). Linear regression analysis established radiographic equations for frailty-adjusted GAP Scores at baseline and 2-years involving relative pelvic version, relative lumbar lordosis, lordosis distribution index, relative spinopelvic alignment, and an age factor to formulate a sagittal plane score. Patients were restratified into frailty-adjusted proportionality groups: Proportional (<5.8), Moderately Disproportional (MD) (5.8-7), Severely Disproportional (SD) (>7). Frailty-adjusted GAP proportionality at 2-years were compared to adjusted-BL to determine whether patients improved, deteriorated or remained the same in their spine proportion.
RESULT(S): A total of 140 patients were included (55.5+/-16.4 yrs, 77.5% female, 25.2+/-4.7 kg/m2). BL frailty: 32.8% not frail, 67.2% frail. Primary analyses demonstrated correlation between BL frailty score and BL and 2-year GAP scores(P<0.001). Linear regression analysis(p<0.001) developed a frailty-adjusted GAP threshold equation: 4.4 + 0.93*(frailty score). Adjusted-baseline scores were taken and re-stratified based distribution and placed 26.4% of patients in Proportional, 26.6% MD, and 44% SD. BL adjusted GAP scores by frailty group: 5.3 Not Frail, 7.5 Frail; p<0.001. At 2-years, GAP scores were grouped into the frailty-adjusted proportionality groups: 66.2% Proportional, 10.8% MD, and 23.1% SD. Patients who were 2-year MD/SD underwent significantly more reoperations (>33.5%) compared to Proportional (12.8%), p=0.015. SD 2-year patients developed increased PJK at the 1-year mark (40%, Proportional: 13.9%, MD:7.1%, p=0.003), as well as had worse 2-year ODI and SRS-22 satisfaction scores(p<0.050). 47.5% improved in GAP (63.4% of frail patients), 12.3% deteriorated, and 40.2% remained in the same proportionality group at 2-year follow up.
CONCLUSION(S): Significant associations exist between frailty and spinal proportion. By adjusting the GAP proportionality groups accounting for baseline frailty contributed to improved outcomes and minimized reoperations. The adjusted GAP groups appeal for less rigorous spine proportion goals in severely frail patients. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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