Faculty Bibliography

BACKGROUND CONTEXT: The Dubousset Functional Test (DFT) is a novel functional assessment tool. It has been shown that patients with spinal pathology take significantly longer to complete the DFT than do control patients. There has been a recent focus in the literature on using functional assessment to predict patient outcomes. PURPOSE: To investigate the relationship between patients' performance of the novel four-component functional test proposed by Dubousset, sagittal alignment and patient-reported outcome measures PROMs. STUDY DESIGN/SETTING: Prospective, single center study. PATIENT SAMPLE: Patients presenting to a single institution for lumbar degenerative disease or spinal deformity. OUTCOME MEASURES: The correlation between time to complete DFT, radiographic measures of sagittal alignment and PROMs.
METHOD(S): This is a prospective, single-center study including primary patients who presented for evaluation of lumbar degenerative disease and spinal deformity. DFT is a test which assesses 4 domains: Up and Walking Test (UWT), Steps Test (ST), Down and Sitting Test (DST), Dual Tasking Test (DTT). The UWT asks the patient to sit-to-stand unassisted, walk 5 m, and sit unassisted. ST asks the patient to ascend 3 steps, turn, and descend 3 steps. DST asks the patient to sit from standing, and then stand from sitting, both unassisted. Finally, DTT asks the patient to walk 5 m and back while counting down from 50 by 2. Each test was timed, and performance was scored in seconds required to finish the test. Spinopelvic radiographs and PROMs (EQ5D, ODI, SF12) were collected. DFT performance was stratified by 40th (Fast) and 60th (Slow) percentile cutoffs. Radiographic sagittal parameters were compared between groups. Regression models were built to predict DFT domains performances using alignment parameters.
RESULT(S): A total of 55 patients were included (52y, 66%F, BMI 25.6). Patients in all DFT Slow domains had significantly worse ODI (all above 40), EQ5D (all below 0.5), and worse SF12_PCS (all below 32) except DTT Slow patients who had a comparable PCS to Fast. UWT Slow patients had significantly greater PI-LL (15 vs 2), lower LL (45 vs 60), and greater PT (22 vs 12); DTT Slow had greater PT (22 vs 11); DST Slow had greater PT (23 vs 12), and greater PI-LL (13 vs 1); ST and DTT slow patients had comparable radiographic parameters to ST and DTT Fast; however, they were older (59 vs 43 ys) (all p <0.05). Greater PT correlated with longer time to perform UWT and DST (r=0.451, r=0.488, respectively, p < 0.05). Greater PI-LL correlated with longer UWT (r=0.349) and loss of LL with longer ST (r=0.416), all p <0.05. Notably, loss of L4-S1 correlated with slower UWT (r=0.377, p <0.05). Regression models revealed that PT, PI-LL and SVA together predict UWT with r=0.472, DST with r=0.370, DTT with r=0.310, and ST with r=0.149.
CONCLUSION(S): The Dubousset Functional Test correlates with sagittal radiographic parameters and PROMs. PT, SVA, and PI-LL were able to predict up to 25% of patients' performance on the functional testing. Although radiographic parameters are helpful in guiding ASD treatment, they should be supplemented with other forms of patients' assessment which may include functional testing. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Preoperative risk stratification is critical to determining which adult spinal deformity (ASD) patients may develop postop complications and to maximize surgical success. Currently it is unknown if a preoperative inflammatory state results in a higher risk for postop complications. This information can be used in risk stratification models to aid in complication avoidance. PURPOSE: To determine if patients with preoperative elevated serum markers for inflammation have higher rates of postoperative complications STUDY DESIGN/SETTING: Retrospective review of multicenter prospective ASD database. PATIENT SAMPLE: ASD patients. OUTCOME MEASURES: C-reactive protein (CRP), Erythrocyte sedimentation rate (ESR), complications by type and by severity of intervention: none, mild, moderate and severe. Demographic and surgical variables: age, estimated blood loss (EBL), operating room (OR) time, body mass index (BMI), America Society of Anesthesia physical classification scale (ASA), Charlson comorbidity index (CCI), Edmonton frailty scale (EF), 3-column osteotomy (3CO), number of post fusion levels.
METHOD(S): Preoperative labs were drawn on ASD patients and the inflammatory markers were CRP and ESR. CRP thresholds for cardiac risk: normal = 3. The CRP moderate and elevated values were combined into one group named elevated. Normal ESR thresholds: Male age 50, =20, Female >50, =30. Patients were stratified by having normal or elevated markers and rates of complications were compared between the groups. A multivariate model with CRP/ESR and demographic/surgical variables for postoperative complications. Health-related quality of life (HRQOL) metrics were compared RESULTS: The total number of patients with preoperative CRP was 159 and ESR was 158. CRP: normal=114 patients (71.7%), moderate elevation=28 (17.6%), severe elevation=17 (10.7%). Combined elevated=45/159(28.3%). Elevated ESR=25(15.8%), normal=133(84.2%). The elevated CRP group had significantly higher rate of moderate complication 13/45(28.9%) vs 16/114(14.0%), p=0.03 and severe complication 15/45 (33.3%) vs 17/114(14.9%, p=0.009. Elevated ESR patients had significantly higher rate of moderate complication 9/25 (36.0%) vs 20/133 (15.0%), p=0.01. In multivariable logistic regression elevated CRP had odds ratio for moderate complication of 3.3 (95% CI 1.4-7.6, p=0.006), and for severe complication of 2.3 (95% CI 1.05-5.1, p=0.037). Multivariable logistic regression for elevated ESR and moderate complication had odds ratio of 2.9 (95%CI 1.04-7.8, p=0.041). Elevated CRP also had significantly higher rate of wound complications (15.6% vs 3.5%, p=0.007) and MSK complications (11.1% vs 1.8%, p=0.01). Elevated ESR had significantly higher rate of cardiac complications (32.0% vs 13.5%, p=0.02) and neurological complications (24.0% vs 9.0%, p=0.03). Elevated CRP had worse preoperative leg pain, SRS Activity and VR12 PCS(p<0.05). Elevated ESR had worse baseline ODI (p=0.03).
CONCLUSION(S): A preoperative inflammatory state as defined by elevated CRP and ESR is an independent risk factor for the development of moderate and severe postop complications. Having elevated preop CRP is 3.3 and 2.3 times more likely to have a moderate and severe complication, respectively. Elevated ESR is 2.9 times more likely to have a moderate complication. This data can be used in risk stratification models to aid in minimizing postoperative complications. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Bone Morphogenetic Protein-2 (BMP-2) has not shown superior benefit in terms of overall cost-effectiveness after implementation during adult spinal deformity (ASD) surgery. However, it remains to be shown whether certain discrete populations do obtain cost-utility from use of BMP-2. PURPOSE: Generate a score to determine usage of BMP-2 and correlate with rates of pseudarthrosis. STUDY DESIGN/SETTING: Retrospective cohort study of a single-center ASD database. PATIENT SAMPLE: A total of 689 ASD patients. OUTCOME MEASURES: Cost utility, pseudarthrosis.
METHOD(S): ASD patients with BL and 2-year(2Y) data included. BMP-2 kit size and cost: small - 4.2 mg ($21,800), medium - 8.4 mg ($23,667), large - 12 mg ($25,617). Published methods converted ODI to SF-6D. QALYs utilized a 3% discount rate for residual decline. Cost was calculated using the PearlDiver database and assessed for Complications and Comorbidities and Major Complications and Comorbidities according to CMS.gov definitions. Binary logistic regression analyses determined significant predictors for development of pseudarthrosis. Established weights were generated for predictive variables via back-step logistic regression for a risk score to predict development of pseudarthrosis. Risk score was then validated via Receiver Operating Characteristic (ROC) curve method analysis. Categories via conditional inference tree (CIT) analysis-derived thresholds were tested for cost-utility of BMP-2 usage. Marginalized means for utility gained and Cost per QALY were calculated within each risk score category, controlling for age, history of prior fusion, and baseline deformity and disability.
RESULT(S): Included: 387 ASD patients. Of 387, 64% received BMP-2 (1% small, 4% medium, 59% large). There were 17 (4.4%) of patients that developed pseudarthrosis by two years, 9 (2.3%) of which underwent reoperation. BMP-2 use, regardless of kit size, did not significantly lower pseudarthrosis rates overall (OR: 0.4, [0.2-1.04]). A predictive risk score for development of pseudarthrosis was formed by the following preoperative variables: age, frailty, history of diabetes, osteoporosis, depression, ASA grade, and baseline L4-S1 and T1PA. Via ROC method, this predictive risk score generated an AUC of 0.87. Following CIT machine learning, thresholds for the BMP Risk Score were derived: >5 No Risk (NoR), 3-5 Low Risk (LowR), 2-3 Moderate Risk (ModR), and <2 High Risk (HighR). The rates of pseudarthrosis for each category were: NoR - 0%; LowR - 1.6%; ModR - 9.3%; HighR - 24.3%. When assessing BMP-2 use and its cost-utility within each group, patients receiving BMP-2 had similar QALYs to those that did not receive BMP-2 (0.163 vs 0.171, p=.65). BMP-2 usage had significantly worse cost-utility in both NoR and LowR cohorts (both p<.05). In ModR patients, BMP-2 usage had equivocal cost-utility ($680,532.35 vs $580,380.21, p=.14). In the HighR cohort, the cost-utility difference narrowed even further (BMP-2 use: $743,155.21 vs $719,628.79, p=.82).
CONCLUSION(S): Our study shows BMP-2 has equivocal cost-utility within those at moderate and high risk for developing pseudarthrosis within two years following spinal deformity correction. The generated predictive score can better aid spine surgeons assess risk and enhance justification for the use of BMP-2 during surgical intervention for adult spinal deformity. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Recent literature has pointed to the rising use of prone lateral versus lateral decubitus positioning in minimally invasive spine surgery (MISS) as a method to reduce operative time, increase patient safety, and aid in surgical accessibility. However, there is a paucity of literature as to how prone lateral and lateral decubitus positioning compares in terms of reaching optimal postoperative outcomes and reducing complication rates. PURPOSE: To assess differences between prone lateral and single-position lateral decubitus positioning compares in terms of reaching optimal postoperative outcomes and reducing complication rates. STUDY DESIGN/SETTING: Retrospective review of prospective MIS database. PATIENT SAMPLE: A total of 524 MIS patients. OUTCOME MEASURES: HRQLs; complications; surgical factors.
METHOD(S): MISS patients with BL) and 2-year(2Y) postop radiographic/HRQL data were included. Patients positioned in the prone latera (PL) or single-position lateral decubitus (LD) position were isolated. At 2Y, an optimal outcome score was calculated using 4 equally weighted criteria: 1) achieving ideal PT per SRS-Schwab at 2Y, 2) Achieving ideal PI-LL per SRS-Schwab at 2Y, 3) No complication requiring reoperation, 4) Achieving NRS MCID by Salaffi et al. criteria; optimal score threshold was set at meeting 2 of 4 criteria. Means comparison analysis assessed differences in radiographic and clinical outcomes at BL and 1Y postoperatively. ANCOVA assessed estimated marginal means adjusting for BL age and revision status.
RESULT(S): Thirty-four PL and 36 LD patients were included (54.40+/-12.49 years, 40% female, 30.93+/-6.52 kg/m2, mean CCI: 2.23+/-1.55) were included. At baseline, patients were comparable in age, gender, BMI and CCI (all p>.05). Perioperatively, PL patients demonstrated significantly lower operative time (200.09 vs 284.54 min, p=.007) and EBL (332.35 vs 192.05 mL, p=.027). Though optimization scores were equivalent between groups (p=.160), PL patients demonstrated significantly lower perioperative complication rates (p=.012), neurological complication rates (p=.006), and had a fewer number of total complications by 2Y (p=.014). When controlling for BL age and revision status, the PL patients demonstrated consistently fewer intra- and perioperative complications as well (both p<.015). In terms of patient-reported outcomes, PL patients also demonstrated significantly improved NRS-Leg scores compared to LD patients by 1Y (p=.038).
CONCLUSION(S): Patients placed in the PL position during minimally-invasive adult spinal deformity surgery demonstrate decreased mean operative times and decreased intraoperative invasiveness and blood loss versus patients operated on via single-position LD positioning. Though overall rates of achieving optimal outcome remain comparable, PL approach should be considered as there may be significant additional benefit in reducing peri- and postoperative complications by 2Y. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: As surgical techniques for deformity correction evolve towards minimizing tissue trauma, further clarity is warranted to define differences in complication profiles between cMIS and open surgeries. PURPOSE: To compare cMIS and open surgery reoperation rates and identify contributing etiologies to reoperation in each cohort. STUDY DESIGN/SETTING: Prospective multicenter observational series. PATIENT SAMPLE: Database enrollment required age =18 years, adult spinal deformity and circumferential minimally invasive spine surgery. OUTCOME MEASURES: Reoperation rate, patient reported outcomes (PROMS), spinopelvic parameters, mechanical failures (defined as rod breakage/dislocation, screw breakage/loosening, set screw loosening, proximal/distal junctional kyphosis, pseudoarthrosis) and other factors contributing to re-operation such as wound infection, medial breach, nerve impingement by screw, vertebral body fracture, sagittal/coronal imbalance, and wound infection.
METHOD(S): A total of 85 patients (pts) with cMIS for ASD with 2-year follow-up (2YFU) were identified and propensity matched to 85 patients in open cohort. Propensity matching was performed based on pre-operative PT, PI-LL, BMI, and SVA. Patient demographic variables, reoperation rate, and complications contributing to reoperation were compared with uni- and multi-variate analysis at any time in each cohort (33 open, 17 cMIS). PROMS at 2YFU were compared in the reoperated cohorts.
RESULT(S): Total of 33 reoperation in the open cohort vs 17 in cMIS were identified. The reoperation rate was significantly higher in the open cohort at 39% (33/85) compared to 20% (17/85) in the cMIS cohort (P= 0.012). The reoperation rate in open cohort related to mechanical failure was 52% (17/33) compared to 35% (6/17) in cMIS cohort (P= 0.43). No significant difference was found in rates of specific etiologies contributing to complications in the cMIS vs open reoperation cohorts under uni- and multivariate analysis. The change in spinopelvic parameters among the two reoperation cohorts at 2YFU were statistically not significant (deltaCVA, deltaSVA, deltaPI-LL, deltaPT, deltaLL CA, deltaTL CA). Under univariate analysis, the following PROMS were similar: ODI, NRS Leg and Back Pain, EQ5D, EQ5D-VAS, SF-36 PCS,SF-36 MCS. However, SRS-22 in open cohort was significantly higher at 2YFU (3.55 +/- 0.73 open vs. 3,10 +/- 0.56 MIS, p = 0.029).
CONCLUSION(S): Findings in our ongoing study show that cMIS procedures were associated with a significantly lower reoperation rate compared to open surgical approaches. PROMS and the change in spinopelvic parameters were similar at 2YFU in both reoperated cohorts (except for SRS-22 favored open cohort). 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) patients maintain upright posture by compensating through their spine, pelvis and lower extremities. Little data exist quantifying the contribution of lower extremity compensation through the hips, knees, and ankles to maintain upright posture. PURPOSE: Evaluate the effect of the lower limb compensation by numerically unfolding patients. STUDY DESIGN/SETTING: Multicenter, prospective cohort. PATIENT SAMPLE: A total of 288 patients surgically treated for complex ASD with preoperative full body images. OUTCOME MEASURES: Horizontal distance between vertebra centroid and ankle.
METHOD(S): Surgical ASD patients were enrolled into a prospective study based on three criteria deformity severity (PI-LL>25degree, TPA>30degree, SVA>15cm, TCobb>70degree or TLCobb>50degree), procedure complexity (>12 levels fused, 3CO or ACR) and/or age (>65 and >7 levels fused). Preop full-body images were evaluated and age and PI-adjusted normative values were used to model spine alignment based upon three configurations: COMP (all lower extremity compensatory mechanisms maintained), PARTIAL (removal of ankle dorsiflexion and knee flexion, maintained hip extension), UNCOMP (ankle, knee, and hip compensation eliminated by reset PT to the age and PI norms). The three configurations were compared, and COMP alignment was stratified by TPA percentiles to investigate the offsets from each vertebra to the ankle joint acting as a surrogate of the gravity line in free-standing position.
RESULT(S): A total of 288 patients met inclusion criteria (60+/-15yo, 70.5% female, 27.4+/-5.9 BMI). COMP spine deformity magnitude included PI-LL 15+/-24, TPA 24+/-14, and SVA 65+/-69mm. As the model transitioned from COMP to UNCOMP alignment, the initial posterior translation of the pelvis decreased significantly to an anterior translation vs the ankle (P.Shift 30 to -7.6 mm). This was associated with a decrease in pelvic retroversion (PT 24.1 to 16.1), hip extension (SFA 203 to 200), knee flexion (KA 5.5 to -0.4), and ankle dorsiflexion (AA 5.3 to 3.7). As a result, the anterior malalignment of the trunk significantly increased SVA (65 to 120mm) and G-SVA (C7-Ankle from 36 to 127 mm), leading to a three-fold increase in bending moments sustained by the ankle joint. The stratification of the COMP position by TPA percentiles revealed that as the deformity increases, the vertebrae above T8 translate anteriorly, those below T10 move posteriorly, with the T8-T10 segment remaining ~3cm posterior to the ankle joint independently of the deformity severity.
CONCLUSION(S): Removal of lower limbs' compensation revealed an unsustainable truncal malalignment with a three-fold increase of bending moments at the ankle joints. Combined, lower limb compensations permit "reducing" the SVA by two-fold and the C7-ankle SVA by three-fold. From a mechanical point of view, this compensation permits maintaining the trunk center of mass (T9) at a fixed offset of ~3 cm from the ankle joint. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Pelvic incidence (PI) serves as the cornerstone for many deformity classifications and realignment schema to create a more individualized realignment target for each patient. Yet, previous literature has linked high PI to problematic outcomes following corrective surgery, including mechanical complications and hip pathologies. PURPOSE: Investigate if patients with high pelvic incidence have increased risk for complications and poor clinical outcomes following ASD surgery. STUDY DESIGN/SETTING: Retrospective. PATIENT SAMPLE: A total of 689 ASD patients. OUTCOME MEASURES: Clinical Outcomes (ODI, SF-36 PCS, MCS), mechanical failure, surgical details.
METHOD(S): ASD patients with 2-year (2Y) data included. Groups: PI >65degree (HighPI) versus PI < 65degree (NormPI). Means comparison tests assessed differences in demographics, surgical details and outcomes between groups. Multivariate analysis controlling for baseline age, frailty, baseline PI-LL, and history of prior fusion, analyzed complication rates and clinical improvement between groups.
RESULT(S): Included: 445 ASD patients. There were 94 (21%) patients presented with a BL pelvic incidence greater than 65degree (HighPI). HighPI patients were older (63 yrs), shorter, with higher BMI and frailty (all p<.05). HighPI were more likely to have had a prior fusion (OR: 1.9, [1.2-3.1]). HighPI were more likely to present with lower physical functioning scores, and severe pelvic compensation (OR: 5.5, [3.4-8.9]) and global deformity (OR: 3.5, [2.2-5.6]). During surgery, HighPI underwent more 3COs (OR: 1.8,[1.1-3.1]) and fusion to pelvis (OR: 2.1,[1.1-3.9]). Upon correction, adjusted analysis revealed HighPI were more likely to be undercorrected in each age-adjusted parameter compared to LowPI (OR: 4.8, [2.9-7.8]). Yet, HighPI patients were less likely to deteriorate within in-construct PI-based alignment (relative lordosis and lordosis distribution) (OR: 0.3,[0.1-0.9]). While not different at six weeks, HighPI were more likely to deteriorate in PI-based global alignment and pelvic compensation from six weeks to two years (OR: 3.2, [1.6-6.5]). This translated to a higher likelihood of developing a major or mechanical complication by 2Y (OR: 1.6, [1.04-2.6]) via adjusted analysis.
CONCLUSION(S): High pelvic incidence is associated with increased frailty, decreased physical functioning, and more severe lumbopelvic and global deformity upon presentation for adult spinal deformity correction. These patients are more often undercorrected by age-adjusted standards and deteriorate in out-of-construct alignment over time even when adequately corrected, leading to higher mechanical complications by two years. Despite our focus on PI-adjusted alignment, we have still not optimized treatment for the patient with high pelvic incidence. Further research should target which surgical techniques and strategies can achieve better results in this population. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The durability of adult spinal deformity (ASD) surgery is key for cost-effective treatment. Malalignment is one of the main reasons for revision surgery. PURPOSE: To investigate risk factors for loss of correction within the instrumented lumbar spine following ASD surgery. STUDY DESIGN/SETTING: Retrospective cohort study of a prospective database. PATIENT SAMPLE: This study included 321 ASD patients with minimum 3 -year follow-up. OUTCOME MEASURES: L1-S1, L4-S1 and L1-L4 lumbar lordosis.
METHOD(S): A total of 321 patients who underwent fusion of the lumbar spine (=5 levels, LIV S1/ilium) with a revision-free follow-up =3 years were identified. Patients were stratified by the change in PI-LL from 6 weeks to 3 years postop as Maintained vs Loss > 5degree. Those with a loss due to instrumentation failure (broken rod, screw pullout, etc.) were excluded before comparisons. Changes in regional and focal lordosis over time were investigated with repeated measures ANOVA and factor comparison.
RESULT(S): Mean age 64 yrs, BMI 28 kg/m², 80% female. The baseline alignment (PI-LL=21+/-19degree, T1PA=26+/-12degree) was corrected to PI-LL=3+/-13degree, and T1PA=18+/-10degree at 3 yrs (mean 3Y follow-up: 45+/-11m, with 44+/-11 mo between early and late follow-up). Eighty-two patients (25.5%) lost >5degree of PI-LL correction (mean loss 10+/-5degree). After exclusion of patients with instrumentation failure, 52 patients (Loss) with a mean loss of correction of 8.6+/-2.9 were compared to 222 controls with maintained LL correction. Demographics were similar between groups (age: 63 vs 61 p=0.15; Sex: 78.4% F vs 88.5% p=0.10). There were no significant differences in use of osteotomy, 3CO, and IBF between Loss and Maintained LL (all p >0.1). There was no significant difference in number of levels fused (11 vs 12 p=0.39), rod material (CoCr 59.4% vs 58.8% p=0.34), and BMP use (88.7% vs 84.6% p=0.41) but Loss had less supplemental rod use (5.8% vs 23.4% p=0.004). Comparison between Maintained and Loss revealed a similar PI-LL mismatch at pre-op (16.7+/-18.7 vs 20.9+/-18.3 p=0.14) and final postop (1.8+/-12.5 vs 5.1+/-14.5 p=0.11) but a significantly smaller PI-LL for Loss at early postop (0.6+/-12.8 vs -3.5+/-13.7 p=0.41). Distally, Maintained had a significant improvement in L4-S1 lordosis from preop to early postop (p=0.013), with no significant difference from early to final follow-up. In contrast, patients in the Loss group had no difference in L4-S1 from preop to early postop (p=0.14), but showed a significant loss of correction at 3 years (p <0.001). Proximally, significant increase between pre and early postop in L1-L4 (all p <0.001), with Loss and Maintained reaching similar early postop value (p=0.34). However, from early postop to final follow up, Loss showed a significant decrease in proximal lordosis (p <0.001) while Maintained did not (p=0.08), corresponding with a smaller absolute L1-L4 in the Loss cohort at 3 yrs (p=0.002). Screw orientation showed a significant decrease from early to late follow-up between the L1 and S1 screws for Loss (1.3+/-4.1 p=0.031), without any changes across the L4-S1 segment (-0.1+/-2.9 p=0.97).
CONCLUSION(S): Approximately a quarter of patients lose an average of 10degree of their 6-week correction by 3 years. Lordosis is lost proximally through the instrumentation (ie, tulip/shank angle shifts and/or rod bending), but lost distally through bone "settling" through the instrumentation itself. The use of supplemental rods and avoiding sagittal overcorrection may help mitigate this loss. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Surgical intervention has been shown to be an effective treatment modality for adult cervical deformity (CD), yet patient-reported outcomes vary even when patients are optimally realigned. While patients with higher baseline disability have more room for improvement, we propose there may be a threshold beyond which greater disability limits health-related quality of life (HRQL) improvement due to elevated risks and a point of no return. PURPOSE: To assess impact of baseline disability on HRQL outcomes. STUDY DESIGN/SETTING: Retrospective study of prospectively enrolled CD patients in a multicenter CD database. PATIENT SAMPLE: A total of 116 CD patients were included. OUTCOME MEASURES: HRQL, neck disability index (NDI), modified Japanese Orthopaedic Association (mJOA), EuroQol-5 Dimension (EQ5D).
METHOD(S): CD patients with baseline (BL) and 2-year follow-up (2Y) were included. The cohort was ranked into quartiles by baseline NDI, from lowest/best score (Q1) to highest/worst score (Q4). Means comparison tests analyzed differences between disability groups. Multivariate Analyses (MVA) assessed differences in outcomes of interest controlling for covariates including BL deformity, HRQLs, surgical details and complications.
RESULT(S): A total of 116 patients met inclusion criteria (age: 60.97+/-10.45 yrs, BMI: 28.73+/-7.59kg/m², CCI: 0.94+/-1.31). The cohort presented with mean BL cSVA was 38.54 +/- 19.43mm, TS-CL: 37.34 +/- 19.73, and mJOA: 13.62 +/- 2.71. Surgically, patients had an average of 8.44 +/- 3.41 levels fused, with 53.5% of patients undergoing decompression and 48.3% undergoing osteotomy. Mean BL NDI and numerical rating scale (NRS) of the cohort were 48.33 +/- 17.99 and 6.74 +/- 2.48 respectively. Mean BL NDI by disability group was as follows: Q1: 25.04 +/- 8.19, Q2: 41.61 +/- 2.77, Q3: 53.31 +/- 4.32, and Q4: 69.52 +/- 8.35. MVA assessing improvement in NRS neck and NRS back, found significant differences between disability groups (both p=.007). Patients in Q2 demonstrated the greatest improvement in NRS neck at 2 years (-3.93), which was greater than those in Q3 (-1.61, p=.032) and Q4 (-1.41, p=.015). Patients in Q2 demonstrated greater improvement in NRS back at 2 years (-1.71), compared to those in Q4 (+0.84, p=.010). Rates of MCID in NRS neck were also significantly different across disability groups (p=.023). Patients in Q2 met MCID at the highest rates (69.9%) of all groups, higher than those in Q4 (30.3%), p=.039. MVA found patients in Q2 demonstrated the greatest improvement in EQ5D at 2 years (+0.082), compared to Q1 (+0.073), Q3 (+0.022), and Q4 (+0.014), p=.034. Finally, patients in Q2 demonstrated the greatest improvement in mJOA score from baseline (+1.517), p=.042.
CONCLUSION(S): Patients in Q2, with mean baseline NDI of 42, consistently demonstrated the greatest improvement in HRQLs whereas those in Q4, with mean baseline NDI of 70, saw the least improvement. Thus, baseline NDI between 39 and 44 may represent a disability "wweet spot," within which operative intervention maximizes patient reported outcomes. Furthermore, delaying intervention until patients are severely disabled, beyond an NDI of 61, limits benefits of surgical correction in 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: Surgical correction of adult spinal deformity (ASD) has been associated with superior alignment and functional outcomes. However, postoperative complication rates remain relatively high. The extent to which potentially modifiable patient-related factors can influence complication rates in adult spinal deformity patients has not been effectively evaluated. PURPOSE: Evaluate the association between modifiable patient-related factors on complications following ASD corrective surgery. STUDY DESIGN/SETTING: Retrospective. PATIENT SAMPLE: A total of 689 ASD patients. OUTCOME MEASURES: Complication and reoperation rates.
METHOD(S): ASD patients with 2-year (2Y) data were included. Complication groups were defined as follows: 1) any complication; 2) major; 3) medical (cardiac event, ileus, etc.); surgical (site infection, wound dehiscence, etc.); 5) major mechanical (implant failure, rod fracture); 6) major radiographic (PJF [proximal junctional failure], pseudarthrosis, adjacent segment disease); and 7) reoperation. Modifiable risk factors included current smoker, obesity (BMI >30kg/m²), osteoporosis, alcohol use, depression (BL SF-36 MCS <35, perMatcham), psychiatric diagnosis and hypertension. Patients were stratified by BL deformity severity in T1PA (LowDef/HighDef) and age above or below 65 (Young/Older). Means comparison tests assessed prevalence of modifiable risk factors present in those developing specified complications. Binary logistic regression analysis was used to adjust for confounders.
RESULT(S): A total of 480 ASD patients met inclusion criteria (age 59+/-15 yrs, 77%F, BMI 27+/-5 kg/m², CCI: 1.7+/-1.7). By 2Y, comp rates: 72% one complication, 28% major, 21% medical, 27% surgical, 11% major radiographic, and 8% had a major mechanical complication. A total of 106 patients (22%) required reoperation. Overall, 318 patients (66%) had at least one of the preoperative risk factors. Age-Deformity Groups: 32% Young LowDef, 19% Young HighDef, 18% Older LowDef, 31% Older HighDef. Within Young LowDef, patients with osteoporosis were more likely to suffer either a major mechanical or radiographic comp (both OR >6, p<.05), although this trend was not seen in the overall cohort. Young HighDef patients were much more likely to develop complications if obese, especially major mechanical complications (OR: 2.8, [1.04-8.6]; p=.045), while patients with depression or a psychiatric diagnosis suffered major radiographic comps and underwent reoperation more often. Older patients with HighDef developed significantly more complications when diagnosed with depression, including major radiographic comps (23% vs 8%, OR: 3.5, [1.1-10.6]; p=.03). Overall, when controlling for baseline deformity, frailty, and osteoporosis, a diagnosis of depression proved to be a significant risk factor for development of major radiographic complications (OR: 2.4, [1.3-4.5]; p=.005).
CONCLUSION(S): Certain modifiable patient-related factors, especially mental health status, are associated with increased risk for complications following spinal deformity surgery. Therefore, with consideration to clinical presentation, elaborate on the utility in medical intervention prior to undergoing spinal deformity corrective surgery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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