Faculty Bibliography

OBJECTIVE:To prioritize the cervical parameter targets for alignment. METHODS:Included: cervical deformity (CD) patients (C2-7 Cobb angle > 10°, cervical lordosis > 10°, cervical sagittal vertical axis [cSVA] > 4 cm, or chin-brow vertical angle > 25°) with full baseline (BL) and 1-year (1Y) radiographic parameters and Neck Disability Index (NDI) scores; patients with cervical [C] or cervicothoracic [CT] Primary Driver Ames type. Patients with BL Ames classified as low CD for both parameters of cSVA ( < 4 cm) and T1 slope minus cervical lordosis (TS-CL) ( < 15°) were excluded. Patients assessed: meeting minimum clinically important differences (MCID) for NDI ( < -15 ΔNDI). Ratios of correction were found for regional parameters categorized by primary Ames driver (C or CT). Decision tree analysis assessed cutoffs for differences associated with meeting NDI MCID at 1Y. RESULTS:Seventy-seven CD patients (mean age, 62.1 years; 64% female; body mass index, 28.8 kg/m2). Forty-one point six percent of patients met MCID for NDI. A backwards linear regression model including radiographic differences as predictors from BL to 1Y for meeting MCID for NDI demonstrated an R2 of 0.820 (p = 0.032) included TS-CL, cSVA, McGregor's slope (MGS), C2 sacral slope, C2-T3 angle, C2-T3 SVA, cervical lordosis. By primary Ames driver, 67.5% of patients were C, and 32.5% CT. Ratios of change in predictors for MCID NDI patients for C and CT were not significant between the 2 groups (p > 0.050). Decision tree analysis determined cutoffs for radiographic change, prioritizing in the following order: ≥ 42.5° C2-T3 angle, > 35.4° cervical lordosis, < -31.76° C2 slope, < -11.57-mm cSVA, < -2.16° MGS, > -30.8-mm C2-T3 SVA, and ≤ -33.6° TS-CL. CONCLUSION/CONCLUSIONS:Certain ratios of correction of cervical parameters contribute to improving neck disability. Prioritizing these radiographic alignment parameters may help optimize patient-reported outcomes for patients undergoing CD surgery.

BACKGROUND CONTEXT: Surgeons may preferentially limit fusion levels for younger vs older ASD patients to maintain motion segments and optimize postoperative function. Few data exist comparing the functional impact of upper thoracic (UT) vs thoracolumbar (TL) upper instrumented vertebra (UIV) in younger vs older ASD patients undergoing long fusion to the pelvis. PURPOSE: Evaluate patient reported functional impact of UT vs TL UIV in younger vs older ASD patients undergoing long fusion to the pelvis. STUDY DESIGN/SETTING: Propensity score matched (PSM) analysis of ASD patients prospectively enrolled into a multicenter study. PATIENT SAMPLE: Surgically treated ASD patients prospectively enrolled into multicenter study. OUTCOME MEASURES: Numeric rating scale (NRS) back and leg pain, Scoliosis Research Society-22r questionnaire (SRS-22r), Short Form-36v2 questionnaire (SF-36), Oswestry Disability Index (ODI), estimated blood loss, duration of hospital stay, postoperative complications, revision spine surgery.
METHOD(S): Surgically treated ASD patients prospectively enrolled into a multicenter ASD study were divided into 2 age groups (younger= <65 years, older= > 65 years) and separated according to UIV (TL= L2-T7; UT= T6-T1). Study inclusion criteria; 1) surgery for Lumbar (L), Sagittal (S), or Mixed (M) deformities (as per SRS-Schwab ASD classification), 2) fusion to the pelvis, 3) minimum 5 levels fused, and 4) minimum 2 year postop follow up. Surgery for double major or thoracic scoliosis were excluded. PSM was used to match preop patient demographics, scoliosis, and sagittal spinopelvic parameters including PI-LL, TK, SVS, and TPA. Surgical data evaluated and impact of UIV upon patient reported functional outcomes compared for UT vs TL for younger vs older.
RESULT(S): From 2008-2018, 435 of 717 eligible surgically treated patients were evaluated; younger (n=193; mean age 57.6 years) and older (n=242; mean age 72.3 years), mean levels fused UT=17.4, TL=10.7 (p<0.05). Preop spine deformity, demographics, and performance of osteotomies were similar for matched UT vs TL in younger and older (p>0.05). Surgical blood loss, duration of SICU and hospital stay was greater for UT vs TL in younger and older (p<0.05). UT had more revision surgery than TL due to implant failures in younger (20% vs 3%) and older (16% vs 1%), respectively (p<0.05). Older UT had more major complications than older TL (65% vs 30%). At minimum 2 year postoperative follow up spine deformity correction and all PROMs (including improvements and final values) including SRS-22r activity, SF-36 physical function, SF-36 role physical, SF-36 social function and SF-36 vitality were similar UT vs TL in younger and older (p>0.05).
CONCLUSION(S): Younger ASD patients fused to the pelvis do not report more physical restrictions for UT vs TL UIV compared to older ASD patients, however blood loss, SICU and hospital stay and complications were greater for UT vs TL in younger and older cohorts. When deciding upon UIV for ASD patients, the minimal impact of UT vs TL UIV upon patient reported outcomes must be offset by cognizance of a longer hospital stay and potential for greater postoperative complications for UT fusions especially in older patients. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Few guidelines exist regarding appropriate upper instrumented vertebra (UIV) selection for adult spinal deformity (ASD) patients undergoing long fusion to the pelvis. Fusion to upper thoracic (UT) spine may provide greater deformity correction and reduce proximal junctional failure (PJF) rates compared to fusions terminating at the thoracolumbar (TL) spine. Previous reports comparing outcomes for UT vs TL UIV for ASD surgery are confounded by discrepant patient cohorts. PSM analyses can be used to reduce selection bias and mimic patient randomization. PURPOSE: Use a propensity score matched (PSM) analysis to compare surgical and hospital data, deformity correction, complication rates, and patient reported outcomes (PROs) for demographically and radiographically matched ASD patients receiving TL vs UT UIV. STUDY DESIGN/SETTING: PSM analysis of ASD patients prospectively enrolled into a multicenter study. PATIENT SAMPLE: Surgically treated ASD patients. OUTCOME MEASURES: Numeric rating scale (NRS) back and leg pain, Scoliosis Research Society-22r questionnaire (SRS-22r), Short Form-36v2 questionnaire (SF-36), Oswestry Disability Index (ODI), estimated blood loss, duration of hospital stay, postoperative complications, revision spine surgery, PJF.
Method(s): ASD patients prospectively enrolled into a multicenter study from 2009-2018 were classified according to SRS-Schwab ASD Types. Study inclusion; 1) surgery for lumbar (L), sagittal (S) or mixed (M) deformities, 2) fusion to pelvis, 3) >=5 levels fused, 4) >=2 year follow up. Study exclusion; double major or thoracic scoliosis, thoracic hyperkyphosis (>70degree). UIV cohorts formed based on bimodal UIV distribution (TL=L2-T8 vs UT=T6-T1). PSM matched TL and UT for preop demographics, scoliosis, PI-LL, TK, SVA, TPA and osteotomies. Postop deformity correction, complications, and PROs were compared for UT vs TL in L, M, S deformities.
Result(s): Of 699 eligible patients, 417 (L [n=70], S [n=166] and M [n=198]) were evaluated. UT and TL had similar preop age, frailty, spine deformity, follow up, osteotomies performed (p>0.05). UT had greater blood loss in L and M deformities, greater SICU admissions for L and S, longer hospital and greater revision surgery for implant failures for all deformities than TL (p<0.05). UT had fewer PJF for L deformities (p<0.05). Deformity correction and PROM improvement was similar UT vs TL for all cohorts at last follow up (p>0.05).
Conclusion(s): The theoretical benefits of UT fusion were not demonstrated for matched L, S and M patients receiving long fusion to the pelvis. UT had greater blood loss, hospital stay and revision surgery for implant failures than TL. For select deformities surgeons should consider TL UIV rather than UT; however, more research is needed to determine best outcomes for fusion levels for ASD. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: T1 slope (T1S) and C2 slope (C2S) are important radiographic parameters for cervical deformity (CD) patients, with higher T1S and C2S both corresponding to worse cervical alignment. In addition, prior research has shown higher T1S is associated with poor global sagittal alignment. These two parameters can be used to group patients into distinct spinal deformities with low T1S-high C2S (LTHC) representing CD only and high T1S-high C2S (HTHC) representing global deformity without cervical compensation. PURPOSE: Examine differences in surgical and radiographic outcomes in surgical CD patients with global deformity (HTHC) vs CD only (LTHC). STUDY DESIGN/SETTING: Retrospective review of a prospective multicenter database. PATIENT SAMPLE: Surgical CD patients with high C2S and minimum 1-year follow-up. OUTCOME MEASURES: Surgical characteristics, Postoperative complications, Neck Disability Index (NDI), and radiographic parameters, such as thoracic kyphosis (TK), T1 pelvic angle (TPA), and C7 sagittal vertical axis (cSVA).
METHOD(S): A prospective multicenter database of operative CD patients was analyzed. Inclusion criteria was patients with at least 1 year of follow-up and preoperative high C2S. High C2S (>30degree) was defined by 1 SD above the previously published mean for asymptomatic subjects with an overall kyphotic cervical morphotype. Patients were categorized as LTHC if T1S <= 30degree and HTHC if T1S > 30degree. Severe Distal Junctional Kyphosis (DJK) was defined as DJK angle change >20degree. Statistical analysis included independent samples t-test and chi-square analysis with significance set to p<0.05.
RESULT(S): Ninety-two patients met inclusion criteria (61 HTHC, 31 LTHC). HTHC had greater preoperative TK (-72.86 vs -46.59degree), TPA (18.01 vs 10.56degree), and cSVA (57.96 vs 38.77mm), all p<.010. At 1-year postop, HTHC had higher TK (-69.40 vs -59.67degree) and cSVA (48.95 vs 39.36mm), both p<.05; though there were greater improvements in TK and cSVA for HTHC, while TK worsened for LTHC. HTHC had more posterior levels fused (10.28 vs 6.65), fewer anterior levels fused (1.16 vs 2.23), and more circumferential fusions (66.7% vs 38.7%), all p<.05. Lower instrumented vertebrae (LIV) was more caudal in HTHC (13.65 vs 9.55, p<.001). Both groups had similar baseline Neck Disability Index (NDI) scores (49.55 vs 49.10), but HTHC had less NDI improvement at 1 year (-6.75 vs -15.47, p=.023). There were no significant differences in rates of postop minor (18.0% vs 12.9%, p= 0.529) or major (11.5% vs 9.7%, p=0.793) complications, severe DJK (1.6% vs 6.5%, p= 0.219), or reoperation (4.9% vs 3.2%, p=0.707).
CONCLUSION(S): HTHC have worse global sagittal alignment than LTHC, both preoperatively and at 1 year postoperatively. They require more aggressive procedures with more levels fused, lower LIV, and more circumferential fusions, but have no differences in postop complications. HTHC had smaller 1 year HRQL improvements, likely due to their continued worse global alignment postoperatively. The relationship of T1S and C2S is important in understanding the burden of global spinal deformity in operative cervical deformity patients. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Since circumferential adult spinal deformity (ASD) surgery can lead to high surgical burden for the patient, surgeons may elect to stage these procedures during the same hospitalization. As a result, there is a trend toward planning same-hospitalization staged ASD surgeries by performing an anterior lumbar interbody fusion (ALIF) prior to a subsequent staged posterior fusion. PURPOSE: The aim of this study was to determine optimal timing for staging (early vs delayed) thoracolumbar ASD surgery within the same hospitalization. STUDY DESIGN/SETTING: Retrospective review of a multicenter database. PATIENT SAMPLE: A total of 158 surgical ASD patients undergoing anterior and staged posterior spinal fusion >=5 levels. OUTCOME MEASURES: Our outcome measures were 90-day complication rates, postoperative alignment, and 2-year ODI.
METHOD(S): Using a prospective, multicenter database, we identified 158 surgical ASD patients undergoing first an anterior surgery followed by a staged posterior spinal fusion >=5 levels during the same hospitalization. Stratum-specific likelihood ratio (SSLR) analysis was performed to calculate a cutoff point beyond which 90-day complications were increased. The cutoff generated through SSLR were confirmed with multivariable logistic regression analysis controlling for age, gender, levels fused for each stage, preoperative alignment, three-column osteotomy, and Charlson Comorbidity Index. The outcome measures were 90-day complication rates, postoperative alignment, and 2-year ODI. Multivariable analyses were performed with logistic, Poisson and linear regressions where appropriate.
RESULT(S): Utilization of staged procedures increased 4x from 2008-2019, and the mean staging interval was 3 days (range 1-8). On SSLR analysis, patients were divided into two staging categories based on complication risk: early (<6 days, range 1-5, N=139) versus delayed (>= 6 day, range 6-8, N=19). On bivariate analysis, the delayed group had higher 90-day complication rates (68.4% vs 32.4%, p=0.002) and longer operative times (638 min vs 739 min, p=0.020) relative to the early group. Adjusting for covariates on multivariable analysis, patients with delayed staging had significantly greater odds of 90-day complications (OR=7.57, p=0.006), and longer total operative time (beta=119, p=0.035). With respect to specific complications, delayed staging carries increased odds of infection compared to early staging (OR=11.8 p=0.031). There were no significant differences in postoperative alignment or 2-year ODI between the groups (p>0.05 for all).
CONCLUSION(S): Compared to early staging (< 6 days) of ALIF and subsequent staged posterior fusion, delayed staging (>= 6 days) is associated with greater odds of 90-day complications, particularly infection. With the growing trend toward staged ASD surgeries, efforts should be made to shorten the interval between ALIF and subsequent posterior fusion. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Few studies investigate fractional curve correction after long fusion with transforaminal (TLIF) vs anterior lumbar interbody fusion (ALIF) for adult symptomatic thoracolumbar/lumbar scoliosis (ASLS). PURPOSE: Our objective was to compare fractional correction, health-related quality-of-life (HRQL), and complications associated with L4-S1 TLIF vs ALIF in ASLS operative treatment. STUDY DESIGN/SETTING: Retrospective review of a prospectively collected multicenter consecutive case registry. PATIENT SAMPLE: Database enrollment required age >=18 years, scoliosis >=20, sagittal vertical axis (SVA) >=5cm, pelvic tilt >=25, or thoracic kyphosis >=60. OUTCOME MEASURES: Radiographic correction (including L4-S1 fractional curve), HRQL (Oswestry Disability Index [ODI], Short Form-36 [SF-36] scores, Scoliosis Research Society-22 [SRS-22r] scores), and complications.
METHOD(S): Prospective multicenter data was reviewed. Study inclusion required fractional curve >=10degree, thoracolumbar/lumbar curve >=30degree, index TLIF vs ALIF at L4-L5 and/or L5-S1, and minimum 2-year follow-up. TLIF and ALIF patients were propensity-matched using number and type of interbody fusion at L4-S1.
RESULT(S): Of 135 potentially eligible consecutive patients, 106 (78.5%) achieved minimum 2-year follow-up (age=60.6+/-9.3years, women=85.8%, TLIF=44.3%, ALIF=55.7%). Index operations had 12.2+/-3.6 posterior levels, iliac fixation=86.8%, and TLIF/ALIF at L4-L5 (67.0%) and L5-S1 (84.0%). ALIF had greater cage height (10.9+/-2.1 vs 14.5+/-3.0mm, p=0.001) and lordosis (6.3degree+/-1.6degree vs 17.0degree+/-9.9degree, p=0.001) and longer operative duration (6.7+/-1.5 vs 8.9+/-2.5hrs, p<0.001). Final alignment improved significantly (p<0.05): fractional curve (20.2degree+/-7.0degree to 6.9degree+/-5.2degree), maximum coronal Cobb (55.0degree+/-14.8degree to 23.9degree+/-14.3degree), C7-sagittal vertical axis (5.1+/-6.2 to 2.3+/-5.4cm), pelvic tilt (24.6degree+/-8.1degree to 22.7degree+/-9.5degree), and lumbar lordosis (32.3degree+/-18.8degree to 51.4degree+/-14.1degree). Matched analysis demonstrated comparable fractional correction (TLIF=-13.6degree+/-6.7degree vs ALIF=-13.6degree+/-8.1degree, p=0.982). Final HRQL improved significantly (p<0.05): ODI (42.4+/-16.3 to 24.2+/-19.9), SF-36 Physical Component Summary (PCS, 32.6+/-9.3 to 41.3+/-11.7), SRS-22r (2.9+/-0.6 to 3.7+/-0.7). Matched analysis demonstrated worse ODI (30.9+/-21.1 vs 17.9+/-17.1, p=0.017) and PCS (38.3+/-12.0 vs 45.3+/-10.1, p=0.020) for TLIF at last follow-up (despite no difference in these parameters at baseline). Total complication rate per patient was not different (TLIF=76.6% vs ALIF=71.2%, p=0.530), but significantly more TLIF patients had rod fractures (RF) (TLIF=28.6% vs ALIF=7.1%, p=0.036). Multiple regression demonstrated 1-mm increase in L4-L5 TLIF cage height lead to 2.2degree reduction in L4 coronal tilt (p=0.011), and 1degree increase in L5-S1 ALIF cage lordosis lead to 0.4degree increase in L5-S1 segmental lordosis (p=0.045).
CONCLUSION(S): Operative ASLS treatment with L4-S1 TLIF vs ALIF demonstrated comparable fractional curve correction (66.7% vs 64.8%) despite significantly larger, more lordotic ALIF cages. TLIF cage height had significant impact on leveling L4 coronal tilt, whereas ALIF cage lordosis had significant impact on lumbosacral lordosis restoration. Advantages of TLIF may include reduced operative duration; however, associated HRQL was inferior and more RFs were detected in this study. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Reoperations following adult spinal deformity (ASD) surgery place a significant burden on patient quality of life and overall health care costs. Despite the common knowledge of frequently occurring complications following ASD surgery that require reoperation, little is known on the cost and timing of these complications. Attempts to optimize the cost effectiveness of ASD surgery requires careful examination of the overall impact, frequency and timing of complications requiring reoperation on total cost of care. PURPOSE: The primary aim of our study was to ascertain the percentage of total cost of care attributed to reoperations, identify the costliest complications requiring reoperation following index surgery and to determine the timing of these complications. STUDY DESIGN/SETTING: Retrospective analysis of a prospective, multicenter study. PATIENT SAMPLE: ASD patients with >4 level fusion and eligible for minimum 2-year follow-up were included. OUTCOME MEASURES: Reoperation rates, Total cost of care.
METHOD(S): ASD patients with >4 level fusion with 2-year follow-up were included. Index and total episode of care (EOC) costs were calculated using Medicare's inpatient prospective payment system (IPPS) for MS-DRGs 453-460 and adjusted for inflation to 2020 real dollars. QALYs gained were calculated using baseline, 1-year, and 2-year SF-6D scores. Complication categories included: PJK (proximal junctional kyphosis), adjacent segment disease, pseudarthrosis, neurologic complications, malignment, implant malposition, and infections.
RESULT(S): DRG data for index and revision surgery was available for 505/889 patients. Mean age was 62.5+12.4 years, 76% women. Eighty-nine patients (18%) required a total of 114 reoperations (range 1-5 per patient). The mean index EOC for the whole cohort was $72,718, compared to a mean cost of $59,130 for each reoperation. Accounting for all reoperations, the tEOC in the revision group was 2.1-times higher than the non-revision group ($151,913 vs $71,978, p<0.0001). The 2-year QALY gain in the revision group was significantly higher than the non-revision group (0.08 vs 0.03, p<0.01). The two most common complications requiring reoperations were PJK (41.2%) and pseudarthrosis (36.8%). Reoperations for PJK and pseudoarthrosis collectively accounted for 77% of reoperation costs, but the majority (53%) occurred after 2 years of index surgery. Infections, implant malposition, or neurologic complications (33% each) were most common requiring reoperations within 30 days of index surgery.
CONCLUSION(S): PJK and pseudarthrosis were the two most common complications requiring reoperation and most occurred most frequently over 2 years after index surgery. Collectively, they contributed to 77% of the total reoperation costs. Efforts to optimize the cost effectiveness of ASD surgery should focus on effective methods to mitigate risk of PJK and pseudarthrosis. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: ASD surgery is associated with postoperative improvements in patient pain and function but is also associated with high complication rates and long recovery. Accordingly, if given a choice, patients may indicate they would not undergo surgery again. PURPOSE: At minimum two years postop, evaluate 1) surgically treated ASD patients for willingness to receive/not receive the same surgery, 2) surgeon willingness to perform/not perform the same surgery, 3) surgeon opinion if the corresponding patient would indicate they would/would not have the same surgery again. STUDY DESIGN/SETTING: Analysis of patient vs surgeon willingness to perform/receive surgery for ASD patients enrolled into a prospective, multicenter study. PATIENT SAMPLE: Surgically treated ASD patients prospectively enrolled into multicenter study. OUTCOME MEASURES: Numeric rating scale (NRS) back and leg pain, Scoliosis Research Society-22r questionnaire (SRS-22r), Short Form-36v2 questionnaire (SF-36), Oswestry Disability Index (ODI), estimated blood loss, duration of hospital stay, postoperative complications, revision spine surgery, patient and surgeon willingness to perform surgery.
Method(s): Surgically treated ASD patients, prospectively enrolled into a multicenter study from 2009-2018, were asked at minimum 2 years postop, using SRS-22r question 22 if, based upon their surgical and recovery experience, they would undergo the same surgery. Surgeons were matched to their corresponding patients and the surgeons asked if 1) surgeon would perform the same surgery on the patient and why/why not, 2) surgeon believed the patient would undergo the same surgery and why/why not. Patients were divided into those that indicated they would (yes) or not (no) have same surgery. Agreement between patient and surgeon willingness for same surgery was assessed and correlations between willingness for same surgery and postop complications, deformity improvement, and PROMs evaluated.
Result(s): Of 961 patients eligible for study, 580 were evaluated. The no group (n=108, 18.6%) had similar levels fused, osteotomies, duration of hospital and SICU stay, and major complications as the yes group. (n=472; 81.4%; p>0.05). No group members were younger (58.5 vs 61.6 years), more frail (ASD frailty scale 3.9 vs 3.3), and at minimum 2-years postop had more complications requiring surgery and worse postop improvements for all PROMs including ODI (3.8 vs 18.9), SF-36 PCS (1.8 vs 10) and SRS-22r total (0.4 vs 0.9), pain (0.5 vs 1.2), activity (0.2 vs0.7), and self-image (0.6 vs 1.3) than the yes group, respectively (p<0.05). MCID was reached in 28-56% of no group vs 62- 81% of yes group. Patient willingness to receive surgery varied by surgical institution (70% to 89%; p<0.05). Surgeons accurately identified yes group (91%) but poorly identified the no group (22%; p<0.05).
Conclusion(s): ASD patient willingness to undergo same surgery is important for counseling. Unwillingness for same surgery was associated with PROMs, MCID and complications requiring surgery. Surgeons were poorly able to identify patients unwilling to undergo the same surgery. More research is needed to understand patient experiences recovering from ASD surgeries. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Cervical alignment and cervical deformity surgery are complex topics. Recently, a score inspired by work on thoracolumbar alignment was developed for cervical alignment (cervical deformity score, CDS). While this score was designed to predict early mechanical failures, its association with patient reported outcomes (PROM) remains unclear. PURPOSE: Investigate the association between PROM, complications, and a newly described cervical deformity score. STUDY DESIGN/SETTING: Retrospective review of prospective multicenter database. PATIENT SAMPLE: A total of 102 adult cervical deformity (CD) patients with at least 1 year follow-up. OUTCOME MEASURES: NDI, neck pain, EQ5D, complication rates.
Method(s): CD patients with baseline and 1-year follow-up were included. Postoperative CDS was constructed using offset from age-adjusted values: SVA [(age -55)*2+25], T1 Slope [(age -55)/4 + 28.7], and TS minus CL [cst: between 26.5 and 14.5degree]. Points were assigned based on the offset from alignment targets and the CDS was the sum of the three individual scores. Association with patient-reported outcomes was investigated using Pearson's correlations. Comparison of CDS between patients with and without complication within 1-year was conducted. Logistical regression controlling for demographic and comorbidities was conducted to identify if CDS was an independent predictor of complications.
Result(s): A total of 102 patients met inclusion criteria (61.7yo+/-10, 66.7% F); 37.6% of them had a history of previous cervical surgery (16.7% previous ACDF, 11.7% previous posterior fusion). Preoperatively, they had elevated disability (NDI: 47.1+/-18.1), pain (NSR Neck: 6.6+/-2.5), myelopathy (mJOA: 13.6+/-2.7) and lower general health (EQ5D: 0.74+/-0.07). They also presented with an overall cervical kyphotic alignment (C2-C7: -6.3degree+/-20.9), a moderate cervical anterior alignment (cSVA: 39mm+/-20; TS-CL: 37.9degree+/-19.4) and a posterior global thoracolumbar alignment (SVA: -3mm+/-68). The median of number of levels fused was 7 [4-9], with 49% treated with a posterior approach and 30.4% with a combined approach; 83.2% received an osteotomy, 44.6% some posterior osteotomy, 16.8% grade 6 or 7. The mean operative time was 368min+/-208, median EBL was 525cc [200 1025], and LOS was 5 days [4 8]. At 1 year, patients improved significantly in terms of disability (NDI: 36.2+/-20.7, 60.8% reached MCID), pain (NSR: 4.1+/-2.9) and general health (EQ5D: 0.79+/-0.08) (all p<0.001). The cervical alignment significantly changed (C2-C7: 7.8+/-14.5m; cSVA: 34mm+/-15; TS-CL: 28.9degree+/-12.6 all p <0.002), with a 1-year CDS of 1.68+/-2.46 (prctl [0 3.25]). There was a significant association between increased CDS and increased disability (r=0.273), pain (r=0.336) and lower general health (r=-0.283). Patient with a lower disability level (NDI<20) had a significantly lower CDS (0.71+/-2.3 vs 2.16+/-2.4 p<0.004). Patients without any complications before 1 year had a lower CDS (0.78+/-2.33 vs 2.18+/-2.40 p=0.005), as did patients without major complications (1.36+/-2.27 vs 2.50+/-.78 p=0.037). Deeper analysis revealed significant differences in terms of CDS for patients experiencing cardiopulmonary, instrumentation and radiographic complications (p<0.05). Multivariate analysis, controlling for age and comorbidities, show 1-year CDS to be a significant predictor of complication (p=0.002, OR=1.409).
Conclusion(s): With better outcomes and lower complication rate, maintaining a proportionate alignment postoperatively can result in superior outcomes following CD surgery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Both frailty and surgical invasiveness are correlated with increased risk of complications following ASD surgery, yet there is no accepted risk-stratification system combining these factors. PURPOSE: The aim of this study is to ascertain data-driven categories defining the risk for 90-day complications following ASD surgery based on frailty and surgical invasiveness. STUDY DESIGN/SETTING: Retrospective review of a multicenter database. PATIENT SAMPLE: A total of 1,272 surgical ASD patients undergoing spinal fusions >=5 levels OUTCOME MEASURES: Ninety-day complication risk, 90-day complication rate, invasiveness thresholds for increased complications.
METHOD(S): Using a prospective, multicenter database, we identified 1,272 surgical ASD patients undergoing posterior spinal fusion of at least five levels. Patients were separated into three frailty groups based on the ASD-FI frailty index. Within each frailty group, stratum-specific likelihood ratio (SSLR) analyses were performed to define frailty-based surgical invasiveness cutoffs associated with increased risk for 90-day complications. Cutoffs generated through SSLR were confirmed with multivariable logistic regression analysis controlling for age, alignment, and ODI.
RESULT(S): Mean age was 60 +/- 14 years, 74% females. Of 1,272 surgical ASD patients, 319 (35%) were nonfrail (NF), 667 (52%) frail (F), and 286 (23%) severely frail (SF). Mean SI was 93 +/- 35. The mean complication rate was 35.4% for NF, 37% for F and 43.6% for SF. SSLR analysis of NF patients produced 2 complication categories: 33% complication rate for SI < 153 and 73% for SI >= 153. NF patients with SI >= 153 had 4.14x higher odds of complications than NF patients with SI <153 (p=0.04). SSLR analysis of F patients produced 3 complication categories: 26% complication rate for SI < 60, 42% for SI of 60 to 179, and 64% for SI >= 180. Relative to F patients with SI < 60, F patients with SI 60 to 179, and SI >= 180 had 2.4x and 6.7x higher odds of complications, respectively (p<0.01 for both). SSLR analysis of SF patients produced 2 complication categories: 35% complication rate for SI < 82 and 49% complication rate for SI >= 82. SF patients with SI >= 82 had 1.77x higher odds of complications than SF patients with SI < 82 (p=0.04).
CONCLUSION(S): Frailer groups were found to have lower SI cutoffs, indicating the less invasiveness surgeries can be performed on frail patients to minimize complication risk. This risk-stratification system is useful for counselling patients regarding their risk of complication. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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