Faculty Bibliography

BACKGROUND CONTEXT: As ASD prevalence increases in our ever-aging population there is a hypothetical concomitant increase in poor bone quality, especially if not recognized and not treated. ASD surgery is expensive and carries a high complication profile. It is important to optimize surgical outcomes and reduce complications especially if modifiable preoperative risk factors can be identified, such as osteoporosis. Additional diagnostic modalities such as a DEXA can add cost, delay diagnosis, and can be an additional insurance hurdle. PURPOSE: Our goal was to examine the utility of HU measurement on preoperative CTs for bone health assessment. STUDY DESIGN/SETTING: Retrospective cross-sectional review of a prospective, multicenter ASD cohort. PATIENT SAMPLE: Surgical ASD patients. OUTCOME MEASURES: Hounsfield Units, history of osteoporosis, DEXA results.
METHOD(S): Operative ASD patients (scoliosis >20, SVA>5cm, PT>25, or TK>60) were included if they had a preoperative CT. HU were measured by each participating site from axial views within the cancellous body (x3: top, middle, bottom) at both L1 and future UIV. Reliability of the measurement between the 3 acquisitions was performed using instar-class correlation for absolute agreement. Association between HU and patient demographics was assess using Pearson's correlation. Finally, correlation between DEXA measurement and HU was conducted to evaluate relationship between bone quality and HU values.
RESULT(S): There were 694/1493 (46%) patients who had a CT including either L1 or UIV. And 521 patients were identified as having both L1 and UIV measurement. Also, 71.8% were female with a mean age of 63years+/-12.5, 52.6% were revision with mean levels fused of 10.5+/-4.5. The intraclass correlation coefficient (ICC) for UIV and L1 were 0.767 (95CI 0.737-0.796]) and 0.802 (95CI [0.774 0.827]), respectively. Previous instrumentation did not affect L1 HU ICC (r=0.798 vs r=0.809) and showed no significant difference in HU value (p=0.232). Comparison of L1 HU between different sites demonstrated no significant difference (p=0.43). Comparison of L1 and UIV did show a significant difference (L1:151+/-77 vs 160+/-62 p<0.001) although there was a significant correlation (r=0.631 p<0.001). The mean HU value at L1 was consistent with previously published values (p=0.542). There were 116 (22.5%) patients who had a DEXA and 97 (18.6%) patients reported a history of osteoporosis. Comparison of DEXA and HU between patients with and without history of osteoporosis showed a significant difference in HU (155+/-76 vs 134+/-79 p<0.001) and but not in DEXA (p=0.07). A significant but weak association between DEXA and HU measurements (r=0.286 & 0.285 p<0.002). HU did not correlate with baseline demographic parameters such as BMI, CCMI, or frailty but did correlate with age (p<0.009 r=-0.215). Similarly, DEXA did not correlate with baseline demographic parameters except for BMI (p<0.002,r=0.298).
CONCLUSION(S): In this large cohort of surgical ASD patients, bone quality assessment was available for 18% of patients via DEXA or 46% via HU on CT. HU measured from an axial image of L1 and UIV appears to be a reliable assessment of bone quality. Previous instrumentation did not alter the measurements. There was a significant but weak correlation when comparing HU to DEXA. Patients with a reported history of osteoporosis had lower HU. 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: Concerns exist regarding disease transmission and cost associated with postoperative nonroutine discharge. Few data exist evaluating impact of nonroutine vs home discharge on readmissions, complications and patient reported outcome measures (PROMs) for adult spinal deformity (ASD) surgery. PURPOSE: Evaluate 30-day readmissions, 90-day return to surgery, postoperative complications, and postoperative PROMs for matched ASD patients receiving nonroutine discharge vs home discharge following surgery. 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), duration of hospital stay, 30-day readmission, 90-day return to surgery, postoperative complications.
METHOD(S): Surgically treated ASD patients prospectively enrolled in a multicenter ASD study were divided into two discharge disposition groups, nonroutine (NON) and home (HOME). NON was further divided into acute rehab (REHAB) or skilled nursing facility (SNF) discharge. Study inclusion criteria; (1) surgery >=5 levels fused, (2) >=2-year follow-up. PSM was used to match NON vs HOME for age, frailty and total levels fused. 30-day hospital readmission, 90-day return to surgery, postoperative complications, one and minimum 2 year PROM data was compared for NON vs HOME, and REHAB vs SNF vs HOME.
RESULT(S): From 2015 to 2019, 241 of 374 eligible treated patients were evaluated and 158 included in this study after PSM (mean 2.7 year follow-up). NON (n=106) and HOME (n=52) had similar age (67.6 vs 67.6 years), ASD-frailty index (3.9 vs 3.9), levels fused at surgery (13.8 vs 13.7), and preop PROMs, respectively (p>0.05). Duration of hospital stay (9.7 vs 10.4 days), 30-day readmission (6.6% vs 6.6%), 90-day return to surgery (9.4% vs10.4%), total complications/patient (2.0 vs 1.5), major complications/patient (0.8 vs 0.5), were similar NON vs HOME, respectively (p>0.05). At last follow-up, HOME demonstrated better ODI (21.6 vs 28.2), SRS-total (3.8 vs 3.5), and SRS-activity (3.7 vs 3.3) than NON, respectively (p<0.05). Sub-analysis of REHAB (N=63) vs SNF (N=41) vs HOME showed similar findings, including similar 30-day readmissions, 90-day return to surgery, and complications (p>0.05) and improved PROMs for HOME vs REHAB and SNF (p<0.05).
CONCLUSION(S): Analysis of 158 operatively treated ASD patients prospectively enrolled into a multicenter study and matched for age, frailty, and surgery performed demonstrated that postoperative discharge to skilled nursing or acute rehab facilities did not reduce 30-day readmissions, 90-day return to surgery, or postoperative complications. At one and minimum two years postop, patients discharged home had better PROMs scores than nonroutine discharge. These data should be considered in conjunction with postoperative needs and the cost and disease transmission risks for nonroutine discharge. 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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BACKGROUND CONTEXT: A previous study utilized normative alignment to determine overcorrections and predict mechanical complications in adult spinal deformity (ASD) surgery. Other studies have recommended alignment targets that optimize age-appropriate physical function. The difference in functional outcomes and mechanical complications between these prescribed alignment targets has not been explored. This study utilizes a component angle of the T1 pelvic angle (TPA) within the fusion to compare normative and age-pelvic incidence (PI) optimal alignment in terms of proximal junctional kyphosis (PJK), proximal junctional failure (PJF) and health related quality of life measures (HRQL). Using the component of TPA within the fusion, the T4-pelvic angle (T4PA), allows for the measurement spinopelvic alignment separate from that of the unfused thoracic spine and any PJK that may occur postoperatively. PURPOSE: To compare ASD patients corrected to normative alignment vs age-PI optimal alignment in terms of PJK/PJF and outcomes. STUDY DESIGN/SETTING: Retrospective analysis of a prospective multicenter ASD database and a database of asymptomatic subjects. PATIENT SAMPLE: This study included 1,916 ASD patients and 118 asymptomatic subjects for formula development; 288 ASD patients with 2-year X-ray and HRQL follow-up. OUTCOME MEASURES: SF36-PCS, ODI, SRS-22, NRS back/leg, PJK (change in UIV to UIV+2 >10degree), PJF (defined as severe PJK with change >21.6degree, or UIV olisthesis, or proximal junctional fracture).
METHOD(S): Baseline relationships between age, PI and T4PA, were analyzed in the ASD patients and compared to the asymptomatic subjects. Linear regression modeling was used to determine alignment based on PI and age in asymptomatic subjects (normative alignment), and in ASD patients, alignment corresponding to age-appropriate functional status (optimal alignment). ASD patients with UIV above T4 were grouped based on their corrections: normative vs optimal. Extreme over or under corrected patients were excluded (greater than or less than 2SD from mean postop T4PA). For each group, the rate of PJK and PJF were determined.
RESULT(S): In the multilinear regression analysis of the 119 asymptomatic subjects, T4PA correlated with age and PI, r=.713, p<.0001. 1916 ASD patients were included in the optimal formula development. In the 288 ASD patients included in the pre- to postop analysis (137 normative, 151 optimal), there was no difference in baseline alignment or HRQL between the groups. At 6 weeks, the normative aligned group had smaller T4PA (4.45 vs 14.1) and PI-LL (-7.24 vs 7.4), all p<.0001. Normative aligned patients had the higher PJK rate (40% vs 27.2%, p=.03) compared with optimal; and a higher PJF rate (17% vs 6.8%, p=.008). PJF patients had -1.2degreeof T4PA offset from normative alignment and -5.2degreeof offset from optimal alignment. By contrast, no PJF patients had 3.8degree of T4PA offset from normative alignment and -0.42degree of offset from optimal alignment. There was a trend toward worse 2-year SF36-PCS in patients who suffered PJF (37.7 vs 41.6, p=.09). Both the Normative and Optimal groups improved in outcomes from baseline to 2-year (p<.001) with no difference in 2-year HRQL.
CONCLUSION(S): Correcting ASD patients to normative alignment resulted in higher rates of PJK and PJF without improvements in HRQL. ASD patients should not be corrected to match the alignment of their asymptomatic unfused peers, rather they should be realigned optimally to match age-appropriate physical function. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Rod failure and pseudarthrosis are common complications following the surgical treatment of adult spinal defomity (ASD). Many strategies have been employed in mitigating these problems, such as interbody fusion, multiple rods, use of more effective biologics, and optimizing spinal alignment. We aimed to study the frequency and type of rod failures in a large ASD population over time. PURPOSE: To study the frequency and type of rod failures in a large ASD population over time. STUDY DESIGN/SETTING: Retrospective review of prospective data. PATIENT SAMPLE: This study included 647 adult spinal deformity patients surgically treated between 2008 and 2018. OUTCOME MEASURES: Rod failures.
METHOD(S): ASD patients with a fusion extended from minimum L1 to pelvis and min 2-year follow-up were included. Radiographs and records were examined to identify characteristics of the rod failures: timing, unilateral vs bilateral, vertebral level, unilateral progressing to bilateral failure, revision and failure rates over time.
RESULT(S): Among the study population, 647/1052 patients met inclusion criteria (age: 64+/-10 yrs., 78% F, BMI: 28.3+/-5.7, Mean follow-up: 37 months +/-13). Surgeries for these patients were performed from 2008 to 2018. The UIV was T7 or above in 306 and T8 or below in 338 patients, most frequent UIV: T4 (121) and T10 (208). A total of 146 patients had a 3COs; 435 had interbody fusion with 187 ALIF, 202 TLIF,135 XLIF; 286 patients had BMP use post only and 203 had BMP use interbody and posteriorly. Overall rod failure rate was 135/647 (21%), of which 9.3% occurred before by 2 years postop. Mean days to failure was 795 day +/- 485 (Median 733). Most frequent failures were in the lower lumbar spine L3-4 (32) 24%, L4-5 (34) 25% and L5-S1 (44) 32%. Of the 97 Unilateral failures, 35 (36.1%) were revised and only 8 progressed to bilateral failure of which 6/8 were revised; 46 Bilateral failure, 24 (52.2%) were revised.Kaplan-Meier analysis shows a survival rate of 89.7% at 2 years with decrease of 5% per year. No significant difference was found between the first 5 years and last 5 years. Comparison of primary vs revision index procedures did not reveal any differences in time to failure nor time to revision. Use of BMP improved survival rate to 91.2% compared to no BMP 83.4% at 2 years.
CONCLUSION(S): Rod failures remain a common complication when treating ASD with a rate of 21%. Among those rod failures, 9.3% occurred within 2 years. The most frequent sites of failure were in the lower lumbar spine. Unilateral failures underwent a lower rate of revision than bilateral. BMP increased rod survivability. Kaplan-Meier analysis demonstrated a survival rate of 89.7% at 2 years with a decrease of 5% per year. The failure rate has not improved when comparing the first 5 years. to last 5 years. We must continue to seek solutions to improve rod durability challenges to improve long-term outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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OBJECTIVE/UNASSIGNED:Deterioration of global coronal alignment (GCA) may be associated with worse outcomes after adult spinal deformity (ASD) surgery. The impact of fusion length and upper instrumented vertebra (UIV) selection on patients with this complication is unclear. The authors' objective was to compare outcomes between long sacropelvic fusion with upper-thoracic (UT) UIV and those with lower-thoracic (LT) UIV in patients with worsening GCA ≥ 1 cm. METHODS:This was a retrospective analysis of a prospective multicenter database of consecutive ASD patients. Index operations involved instrumented fusion from sacropelvis to thoracic spine. Global coronal deterioration was defined as worsening GCA ≥ 1 cm from preoperation to 2-year follow-up. RESULTS:Of 875 potentially eligible patients, 560 (64%) had complete 2-year follow-up data, of which 144 (25.7%) demonstrated worse GCA at 2-year postoperative follow-up (35.4% of UT patients vs 64.6% of LT patients). At baseline, UT patients were younger (61.6 ± 9.9 vs 64.5 ± 8.6 years, p = 0.008), a greater percentage of UT patients had osteoporosis (35.3% vs 16.1%, p = 0.009), and UT patients had worse scoliosis (51.9° ± 22.5° vs 32.5° ± 16.3°, p < 0.001). Index operations were comparable, except UT patients had longer fusions (16.4 ± 0.9 vs 9.7 ± 1.2 levels, p < 0.001) and operative duration (8.6 ± 3.2 vs 7.6 ± 3.0 hours, p = 0.023). At 2-year follow-up, global coronal deterioration averaged 2.7 ± 1.4 cm (1.9 to 4.6 cm, p < 0.001), scoliosis improved (39.3° ± 20.8° to 18.0° ± 14.8°, p < 0.001), and sagittal spinopelvic alignment improved significantly in all patients. UT patients maintained smaller positive C7 sagittal vertical axis (2.7 ± 5.7 vs 4.7 ± 5.7 cm, p = 0.014). Postoperative 2-year health-related quality of life (HRQL) significantly improved from baseline for all patients. HRQL comparisons demonstrated that UT patients had worse Scoliosis Research Society-22r (SRS-22r) Activity (3.2 ± 1.0 vs 3.6 ± 0.8, p = 0.040) and SRS-22r Satisfaction (3.9 ± 1.1 vs 4.3 ± 0.8, p = 0.021) scores. Also, fewer UT patients improved by ≥ 1 minimal clinically important difference in numerical rating scale scores for leg pain (41.3% vs 62.7%, p = 0.020). Comparable percentages of UT and LT patients had complications (208 total, including 53 reoperations, 77 major complications, and 78 minor complications), but the percentage of reoperated patients was higher among UT patients (35.3% vs 18.3%, p = 0.023). UT patients had higher reoperation rates of rod fracture (13.7% vs 2.2%, p = 0.006) and pseudarthrosis (7.8% vs 1.1%, p = 0.006) but not proximal junctional kyphosis (9.8% vs 8.6%, p = 0.810). CONCLUSIONS:In ASD patients with worse 2-year GCA after long sacropelvic fusion, UT UIV was associated with worse 2-year HRQL compared with LT UIV. This may suggest that residual global coronal malalignment is clinically less tolerated in ASD patients with longer fusion to the proximal thoracic spine. These results may inform operative planning and improve patient counseling.