Faculty Bibliography

BACKGROUND CONTEXT: The International Spine Study Group (ISSG) and the European Spine Study Group (ESSG) developed an adult spinal deformity (ASD) specific risk calculator based on the largest and most granular, prospective ASD database. The calculators utilize preoperative radiographic, surgical, and patient-specific variables in order to predict patient-reported outcomes and complication rates at 2 years. PURPOSE: Assess the ISSG-ESSG risk calculator usability in a single institution ASD population. STUDY DESIGN/SETTING: Retrospective cohort study- single surgeon institution. PATIENT SAMPLE: ASD pts: A total of 631 patients undergoing surgery for adult spinal deformity. OUTCOME MEASURES: Improvement from BL SRS-22 [Pain, Function, total], major complications, Oswestry Disability Index (ODI).
METHOD(S): ASD pts were isolated in the single-center ASD Database 2013-2020. Frail pts were isolated (Frail[F] 0.3>0.5). Basic demographics were assessed for these F pts via chi-squared and t-tests. Each F patient was inputted into the ESSG risk calculator to identify individual predictive rates for postoperative 2-year HRQL outcomes as well as major complications. These calculated predicted outcomes were analyzed against those identified from the ASD database in order to validate the calculator predictability in a single center institution via Brier scores. Having a score closer to 1 means the EESG calculator is not predictive of that specific outcome. A score closer to 0 meant the EESG calculator was a predictive tool for that factor.
RESULT(S): A total of 631 ASD pts were isolated (55.8;16.8yrs, 26.68kg/m², 0.95+/-1.3CCI). Of these patients, 7.8% were frail. Fifty percent of frail pts received an interbody fusion, 58.3% received a decompression, and 79.2% had an osteotomy. Surgical details: mean operative time 342.9+/-94.3minutes, mean estimated blood loss 2131.82+/-1011mL, and an average length of stay 7.12+/-2.5days. The EESG calculator predicted the likelihood of improvement for the following HRQL's ODI(86%), SRS-22 Mental Health (71.1%), SRS-22 Total (87.6%), major complication (53.4%). The single institution had lower percentages of improvement in ODI (24.6%), SRS-22 Mental Health (21.3%), SRS-22 Total (25.1%), and lower presence of major complication (34.8%). The calculated Brier scores identified the calculator's predictability for each factor: ODI (0.24), SRS-22 Mental Health (0.21), SRS-22 Total (0.25), major complication (0.28).
CONCLUSION(S): The newly developed ESSG-ISSG risk-assessment tool has a wide application in single institutions as it accurately predicts 2-year outcomes for various SRS-22 questionnaires and development of major complications. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Although researchers have extensively studied factors predicting clinical outcomes at static time points, assessing rate of recovery after adult spinal deformity (ASD) surgery has largely been ignored. This study aims to address this gap in knowledge by evaluating the impact of frailty and invasiveness on recovery kinetics, using area-under-the-curve (AUC) methodology. PURPOSE: To assess the impact of patient specific and surgical factors on postoperative recovery kinetics. STUDY DESIGN/SETTING: Retrospective review of a prospective, multicenter database. PATIENT SAMPLE: A total of 320 patients were identified from a multicenter database who had minimum 2-year HRQOL follow-up, with preoperative, 6-week and 1-year data available. OUTCOME MEASURES: Our primary outcome measure was integrated health state (IHS) score, a marker of postoperative recovery.
METHOD(S): ASD patients with minimum 2-year follow-up were stratified by frailty and surgical invasiveness. Previously validated ASD-FI scores were used to separate non-frail (<.3) patients from those that there were frail (.3 to.5) and severely frail (>.5). Patients were also stratified by surgical inverness, using ASD-SR, into four quartiles, Q1: <65, Q2: 66-89, Q3: 90-119, Q4: >120. Patient demographics, BMI, CCI and surgical parameters were also collected. To assess recovery kinetics, SRS-22r and ODI scores at 6-weeks, 1-year and 2-year were normalized against preoperative values and graphed as a function of time. AUC was summed across all time points to generate a single IHS score. Multivariate linear regression was used with IHS scores as primary outcome variable.
RESULT(S): A total of 320 patients met the inclusion and exclusion criteria. The mean (SD) patient age was 58.6 (14.7) with 79% female. Overall, 139 were non-frail, 131 frail and 46 severely frail. On univariate analysis, frail and severely frail patients were noted to have worse baseline and 2-year HRQOL scores for SRS pain, activity and ODI; however, when comparing differences in HRQOL across this 2-year period, F and SF were noted to have greater improvements in both SRS and ODI (p<.05). On multivariate regression, frail and severely frail patients, compared to those non-frail, were found to have better IHS scores for ODI, SRS-22r pain, and SRS-22r activity, indicating more favorable recovery (p<.05). In particular, for SRS-22r activity, frail (adjusted beta: 0.37, p=<.01) and severely frail (adjusted beta: 0.74, p=<.01) patients were found to have higher IHS compared to their non-frail counterparts. Similarly, for SRS-22r pain, frail and severely frail patients showed improved recovery with higher IHS scores in comparison to non-frail patients. In contrast to frailty, operative variables, including surgical invasiveness and EBL, were insignificant predictors of IHS scores for either ODI or SRS-22r domains.
CONCLUSION(S): Our results suggest that patient-specific factors, namely frailty, play a larger role in predicting postoperative recovery kinetics, in comparison to surgical factors, which appear to have limited if any impact. Despite frail patients having lower preoperative and 2-year HRQOL scores, they were noted to have higher IHS scores SRS pain, activity, and ODI indicating more favorable recovery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: For surgical adult spinal deformity (ASD) patients, determining optimal restoration of alignment and spinal shape is an active area of research. Complex corrective measures taken are in ASD. Incidence of specific alignment outcomes has yet to be investigated in each of the complex realignment ideals. PURPOSE: Assess alignment outcomes (pelvic nonresponse [PNR], PJK, postop cervical deformity [CD]) following ASD-corrective surgery in the context of correction relative to various alignment schemas. STUDY DESIGN/SETTING: Retrospective cohort study of prospective ASD database. PATIENT SAMPLE: A total of 468 ASD patients. OUTCOME MEASURES: PNR, PJK, postop CD.
METHOD(S): ASD patients with preop, 6-week postop (6W), and 2-year postop (2Y) radiographic data included. PNR: 10-year mismatch (undercorrection; unimproved) from a patient's age-adjusted PT at 6W and maintained at 2Y. Pelvic responder (PR): PT +/-10 match age-adjusted goals. Patients were stratified by incremental additions of corrective alignment schemas: (a) improvement in Schwab SVA, (b) matching age-adjusted PI-LL, (c) match postop "ideal" and "theoretical" Roussouly, (d) improvement in proportionality spinal score at 6W. PNR, PJK, and CD development by 2Y were compared within groups, as well as simultaneous improvement/match of the suggested corrective measures (exclusively). In a subanalysis, patients were stratified by severity of baseline PT, low (<20degree), moderate (20-30degree), and severe (>30degree) to determine which alignment schema is necessary to achieve less PNR, PJK and postop CD.
RESULT(S): A total of 468 patients (56.3 yrs, 76.5% F; 25.6% PNR, 40.6% PR) met inclusion criteria. Rates of postop PJK (PNR:49.2% vs PR:59.5%) and CD (18.3% vs 25.8%) were significantly less in the PNR group, p<0.05. Sole improvement in Schwab SVA (73.2%) did not impact PNR, PJK or CD (p>0.050). Undercorrected age-adjusted PI-LL presented with more PNR (60.1%), whereas overcorrected had increased PJK (68.2%), p<0.001. Matching Roussouly at 6W decreased PNR (17.8% vs mismatch:42.3%, p=0.002). 6W proportional spine, had lower rates of PNR (19.7%, severely disproportioned: 58.8%, p<0.001), with postop moderately disproportioned GAP with highest rates of PJK (p=0.010). Incremental addition of alignment schemas was assessed for effect on malalignment outcomes. Schwab and age-adjusted use (20.9%) had less incidence of PNR (28.6% vs 38.7%) than just Schwab. Addition of the Roussouly (18.3%) presented with less PNR (20% vs 30.4%) and PJK (38.5% vs 60.3%) than only Schwab & age-adjusted. Lastly, addition of proportion (16.7%) had 0% occurrence of PNR and CD. Stratifying by baseline PT severity, the low group demonstrated the least incidence of PNR (7.7%) and CD (10.3%) and PJK (41.3%) when matching theoretical Roussouly at 6W (all p<0.050). This remained the same for moderate PT for PNR and PJK, except Schwab improvement decreased postop CD occurrence (21.2%, p=0.049). Severe PT assessment determined PNR (20%), PJK (37.5%) and CD (19.4%) were the lowest with improvement of proportion at 6W (p<0.050).
CONCLUSION(S): Following ASD corrective surgery, 25.6% of patients showed residual pelvic malalignment, qualifying as pelvic nonresponders. Use of complex realignment schemas (SRS-Schwab, age-adjusted, Roussouly shape, GAP) decreased rates of pelvic nonresponse, PJK and postop cervical deformity development. Severe (>30degree) baseline pelvic tilt requires particular emphasis of proportionality in addition to other realignment ideals. 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: Adult spinal deformity (ASD) surgery is complex and may lead to new-onset cervical malalignment and/or proximal junctional kyphosis (PJK). Roussouly et al describes variations in baseline thoracolumbar (TL) shape (Types 1-4), which have been shown to differentially influence surgical ASD outcomes. The effect of morphological shape on patterns of postoperative CD development remains underexplored. PURPOSE: Stratify patients by Roussouly type and assess patterns of conversion from baseline (BL) cervical alignment to postoperative cervical deformity (CD) in patients undergoing thoracolumbar ASD surgery. STUDY DESIGN/SETTING: Retrospective review of a prospective multicenter database of ASD patients. PATIENT SAMPLE: A total of 266 surgical ASD patients. OUTCOME MEASURES: Rate and timing of conversion to CD, rate of PJK, radiographic alignment parameters.
METHOD(S): Operative ASD patients with complete radiographic data at baseline, 6W, 1Y, 2Y, & 3Y intervals were included. Patients were grouped by baseline PI and apex of LL into component types of the Roussouly classification system utilizing pelvic incidence as published by Pizones et al. Patients with no BL CD were postoperatively stratified by Ames CD criteria (TS-CL>20 degree, cSVA>40mm), where CD was defined as fulfilling >1 criteria. Follow-up intervals were established post-ASD surgery, with 6W postop defined as "Early," 6W-1Y "Intermediate," 1-2Y "Late," and 2-3Y "Long." Univariate and Cox regression analyses identified CD conversion rate and PJK rate (<-10degree change in UIV and UIV+2) across Roussouly types 1-4.
RESULT(S): A total of 266 surgical ASD patients (59.7yrs, 77.4% F) with complete radiographic data were included. By Roussouly classification, 9% were Type 1, 15.8% Type 2, 46.6% Type 3, and 28.6% Type 4. 28.6% of ASD patients converted to postop CD (Early: 14.3%, Intermediate: 5.3%, Late: 4.1%, Long: 4.9%). There were no significant differences in CD conversion rate across Roussouly types (1: 33.3%; 2: 28.6%; 3: 26.6%; 4: 30.3%, P=0.895). Types 2 (41.7%), 3 (60.6%), and 4 (43.5%) had their peak rates of conversion in the Early (<6w) window compared to other follow-up intervals, whereas Type 1 patients had a peak rate (50%) between 6w-1Y. Type 2 patients had higher rates of later CD conversion (>1 year) than other types (50% vs 28.1%, P=0.135), while Type 1 patients trended higher rates of earlier CD conversion (<1 year) than other types (33.8% vs 12.5%, P=0.220); these patterns did not reach statistical significance. Across Roussouly Types, among patients who converted to CD, Type 4 had significantly higher rates of ++ SRS-Schwab PT and greater TPA at BL (both p<0.05). Type 4 patients had the highest rate of concurrent PJK with CD conversion (60.9%) compared to Type 1 (50%), Type 2 (50%), or Type 3 (54.5%) (P>0.05). There were no significant change in ODI, PCS, or SRS total among Roussouly Types in patients that converted to CD (p>0.05). Random forest analysis determined the top surgical (levels fused), radiographic (TS-CL), and demographic (frailty) factors associated with CD conversion.
CONCLUSION(S): Baseline thoracolumbar shape as described by the Roussouly classification has a differential effect on timing to CD conversion, though overall rates of CD conversion after TL-ASD correction were similar across Types 1-4. Type 1 patients with a lower apex of lumbar lordosis trended earlier conversion, while Type 2 patients with a higher apex of LL trended conversion beyond 1-year postop. 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: The literature reports age and frailty as strong predictors of outcomes following spine surgery. This postop impact calls for investigation of unique adjustment parameters accounting for the two factors. Grasping the concordance of surgical factors with age and frailty may help surgical planning for individualized, optimal postop outcomes. PURPOSE: Modify the age-adjusted alignment goals with frailty to optimize outcomes in surgical adult spinal deformity (ASD) patients. STUDY DESIGN/SETTING: Retrospective review of a prospective, multicenter spine database PATIENT SAMPLE: A total of 853 patients OUTCOME MEASURES: Age-frailty-adjusted alignment goals (AF); optimal outcomes METHODS: Included: ASD patients with baseline (BL) frailty and ODI scores, radiographic parameters (PT, SVA, PILL, TPA). Patients were dichotomized by the ASD frailty index (not frail, frail). Linear regression analysis established normative radiographic thresholds, utilizing previously published age(A) specific (<35, 35-55, 45-54, 55-64, 65-74, >=75y/o) US-Normative ODI values converted from SF-36 PCS, in conjunction with frailty score. Patients met AF goals if 1-year postop alignment was within one standard deviation (+1SD Overcorrected [Over]; -1SD Undercorrected [Under]).
RESULT(S): A total of 853 patients were included (57.4+/-15yrs, 80%female, 27.2+/-5.9kg/m2). BL frailty: 438 not frail (51.3%), 308 frail (46.8%). Primary analyses demonstrated correlation between BL frailty score, PT, PILL, TPA, SVA, ODI (P<0.001). Linear regression analysis (R: 0.420-0.517,p<0.001) developed AF specific alignment threshold equations: (PT=5.7+0.25[A]+0.86[F]+0.073[ODI]), (SVA=-63.85 +1.23[A]+93.48[F]+0.52[ODI]), (PI-LL=-21.35+0.83[A]+22.89[F]+ 0.083[ODI]), (TPA=-2.91+0.30[A]+10.12[F]+ 0.097[ODI]). Thresholds increased with age and frailty for all four parameters. Patients<35 years and not frail predicted PT:13.3degree, SVA: -13.3mm, PI-LL: -6.6degree, TPA: 7.5degree, while patients>=75 and frail increased in all thresholds (PT: 29.1degree, SVA: 96.9mm, PI-LL: 25.6degree, TPA: 29.6degree). 38.1% patients matched PT ABF, 43.8% SVA, 38.6% PI-LL, and 45.3% TPA. Match PT patients had less PJK incidence 3mos-2yrs (Match:51% vs O/U:55.9%; p=0.173), as well as SVA (Match: 45.5% vs O/U: 60.8%; p<0.001), PI-LL (Match: 42.9% vs O/U: 61%; p<0.01), and TPA (Match: 49.5% vs O/U: 57.8%; p=0.015). PT Match group met MCID for SRS-22 Pain more (p=0.005), while SVA, PILL and TPA Match met MCID for ODI, PCS, and SRS-22 more (p<0.05). Match SVA and TPA had less overall LOS(p<0.01).
CONCLUSION(S): Incorporating frailty with age-specific goals influenced SVA, PT, PILL and TPA. Use of these modified goals is more sensitive to response to surgery than age and contribute to superior clinical and complication outcomes. Specific alignment thresholds accounting for age and frailty appeal for less rigorous alignment goals in older and severely frail patients. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Prior literature has demonstrated that correction of sagittal plane deformity in adult patients has resulted in improvements in health-related quality of life (HRQOL) outcomes. In the absence of sagittal plane pathology, the effects of coronal malalignment under-correction in patients with spinal deformity have not been fully investigated. PURPOSE: To evaluate the impact of coronal malalignment correction on HRQOL outcomes in adult spinal deformity. STUDY DESIGN/SETTING: Retrospective review of a multicenter database. PATIENT SAMPLE: A total of 522 ASD patients had preoperative coronal malalignment greater than 40 mm. We excluded anyone who had SVA greater than 50 mm in order to control for patients without severe sagittal deformities. OUTCOME MEASURES: Our outcome measures included Oswestry Disability Index (ODI), SF-36 Physical Component Summary (PCS), and several other SF-36 and SRS-22r health domains scores.
METHOD(S): Using a prospective, multicenter database, we identified 1560 surgical patients. Of these, 522 patients had preoperative coronal malalignment greater than 40 mm. We excluded anyone who had SVA greater than 50 mm in order to control for patients who only had coronal plane deformity. We only included patients undergoing primary surgery. We then compared 2-year post HRQOL outcomes in patients that had their coronal malalignment corrected (CVA < 40mm) vs not.
RESULT(S): Mean age of patients was 54 +/- 15 years, 91% females. 79 patients were identified with only a coronal plane deformity undergoing a primary ASD surgery. Of these, 38 (48%) were under-corrected and 41 (52%) had their coronal alignment corrected to <40mm. Compared to the corrected group, the uncorrected group had a higher ODI (26.0+/- 2.9 vs 14.7+/- 2.5; p=0.002) and lower SRS-22r Activity (3.6+/- 0.14 vs 4.2+/- 0.11; p=002), SRS-22r Appearance (3.3+/- 0.16 vs 3.9+/- 0.12, p=.001), SRS-22r total (3.6+/- 0.12 vs 4.1+/- 0.11, p=.004), SF-36 Physical Component Summary (40.8+/- 1.3 vs 46.8+/- 1.6; p=.005), SF-36 Physical Function (40.5+/- 1.7 vs 46.0+/- 1.5, p=.01), SF-36 Bodily Pain (41.7+/- 1.6 vs 47.8+/- 1.5, p=.006), SF-36 General Health (47.2+/- 1.8 vs 52.2+/- 1.4, p=.03), SF-36 Social Functioning (45.9+/- 2.1 vs 51.7+/- 1.4, p=.03), SF-36 Mental Health (48.9+/- 1.9 vs 54.2+/- 1.8, p=.048) 2 years following index surgery.
CONCLUSION(S): Patients with coronal malalignment and little sagittal plane deformity experience worse improvement in pain and disability, with under-correction of their coronal plane deformity. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: There have been few investigations into national trends in the use or outcomes of patients treated with robotic assisted surgery. PURPOSE: To evaluate if incorporation of robotic assisted procedures will lead to a rise in suboptimal outcomes. STUDY DESIGN/SETTING: Retrospective review of a national patient database between 2010-2016. PATIENT SAMPLE: A total of 4,109 weighted hospital discharges. OUTCOME MEASURES: Length of stay, complications, invasiveness.
METHOD(S): Inclusion criteria: elective spine surgery procedures as defined by ICD-9-CM and ICD-10-CM codes. Descriptive statistics assessed demographic information for the cohort. Rates of open and MIS robot assisted procedures were assessed, as well as trends in postoperative complications, and length of stay. Propensity score matching was performed between robotic spine surgery patients and non-robotic spine surgery patients for levels fused. Regression analysis was used to assess robot assisted procedures as a predictor of complications and extended LOS (LOS above 75th percentile), unfavorable discharge, and death during hospitalization.
RESULT(S): A total of 4,109 discharges were included. The overall trends in robotic surgery show a significant increase from 2010 to 2016, increasing from 11 recorded cases to 1,535 in 2016 (p<0.001). The majority of cases were open, however, an increasing percentage of cases have been MIS (8% in 2010 vs 12% in 2016, p<0.001). Average length of stay has significantly decreased from 9.5 days in 2010 to 4.4 days in 2016 (p<0.001). Postoperative hardware complications have significantly decreased from a high of 15.6% of cases in 2011 to 0.3% of cases in 2016, as well as DVTs (9.4% in 2011 vs 0% in 2016, both p<0.001). However, overall complication rates have increased, from 25% in 2011 to 29.3% in 2016 (p<0.001). In an analysis of invasiveness matched non-robot assisted patients, robot assisted surgery was not predictive of extended LOS, unfavorable discharge, total post-operative complications, or death during hospitalization (all p>0.05). Robot assisted surgery was predictive of bleeding complications (hemorrhage and hematoma) compared to non-robot surgery patients (OR: 2.05 [1.10-3.82], p=0.02).
CONCLUSION(S): Robot assisted surgery is an increasing implemented technique in spine surgery, with a significant rise from 2010 to 2016. However, during that period there has been a concurrent rise in postoperative complications. Invasiveness matched robot assisted patients were at significantly higher odds of bleeding complications compared to non-robotic patients. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The choice of surgical approach in CD surgery is often dictated by surgeon preference and experience. This choice could significantly impact the costs and outcomes of an operation, therefore the approaches should be analyzed in order to determine the optimal approach from a cost-utility perspective. The cost utility of different surgical approaches in cervical deformity (CD) has not been investigated in the literature. PURPOSE: Investigate the cost utility of differing approaches in operative CD patients. STUDY DESIGN/SETTING: Retrospective review of a prospective multicenter cervical deformity database. PATIENT SAMPLE: A total of 105 CD patients. OUTCOME MEASURES: Costs, EuroQol-5D (EQ-5D), Quality adjusted life years (QALYs), Cost per quality adjusted life years.
METHOD(S): Included CD patients (C2-C7 Cobb>10degreeor CK>10degree, cSVA>4cm or CBVA>25degree) >18yr with follow-up (1-year) surgical and health related quality of life scores. Costs were calculated using the PearlDiver database, which reflects both private insurance and Medicare reimbursement claims. QALYs and cost per QALY were calculated using a 3% discount rate to account for residual decline to life expectancy (78.7 years). After accounting for complications, LOS, revisions, and death, cost per QALY at 1Y and life expectancy [LE] were calculated for surgical approach (anterior-only, posterior-only [excluding PSO and VCR to account for differences in instrumentation], combined). In a subanalysis, approach groups were propensity-score matched for TS-CL to account for baseline (BL) deformity.
RESULT(S): A total of 105 CD patients met inclusion criteria (61.9 yrs, 63% female, 28.6kg/m2, CCI: 0.97). By approach, 21.9% underwent anterior only, 37.1% posterior only and 41% combined approaches. Average number of levels fused was 6.9, with a mean EBL of 948 ml and total operative time of 544.2 minutes. Mean EQ5D at BL was 0.74+/-0.07 and at 1Y was 0.79+/-0.08 (a difference of 0.05+/-0.08). Average difference in EQ5D from BL to 1Y was significant (p=0.002) across approach: 0.093 anterior-only, 0.021 posterior-only, 0.044 combined. 13% (3) of anterior-only patients underwent a revision, 10.3% (4) of posterior and 13.9% (6) of combined approaches. The average costs per surgery for CD patients at 1-year undergoing surgery by anterior approach was $27,640.75, $38,499.44 posterior-only, and $36,553.41 combined approach (p>0.05).The cost per QALY was higher for posterior-only patients at 1-year ($948,946.81) compared to anterior-only ($152,616.65) and combined ($424,110.14), p<0.001. If the utility gained was sustained to life expectancy, the cost per QALY for the anterior-only group was $21,665.87, posterior-only was $134,715.06 and combined approach was $60,207.82., p<0.001. After PSM for TS-CL, 15 patients remained in each group. The cost per QALY remained higher for posterior-only patients at 1-year and LE (both p<0.050).
CONCLUSION(S): After accounting for comorbidities, complications, revisions, and death, all surgical approaches showed improvement in postoperative EQ5D scores, however posterior approach demonstrated overall lower cost effectiveness. CD patients who underwent anterior-only approach had the lowest average costs for CD corrective surgery, as well as the lowest cost per QALY (best cost-effectiveness) compared to posterior and combined approaches. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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