Faculty Bibliography

BACKGROUND CONTEXT: Despite studies reporting the efficacy of BMP to promote surgical spinal fusion, hospital systems and third-party payors continue to deny use of BMP, claiming high cost and lack of long term follow up. PURPOSE: Perform a propensity score matched analysis of complications and cost-effectiveness for surgically treated adult spinal deformity (ASD) patients receiving BMP vs no BMP. STUDY DESIGN/SETTING: Prospective, multicenter, propensity score matched analysis. PATIENT SAMPLE: ASD patients enrolled into a prospective 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), cost of care, cost/QALY, postoperative complications.
METHOD(S): Surgically treated ASD patients prospectively enrolled into a multicenter study from 2009-2018 were assessed for receiving BMP or NOBMP (iliac crest bone graft and allograft only) at the time of surgery. BMP and NOBMP cohorts were propensity score matched (PSM) for age, BMI, frailty, total levels fused, fusion to the pelvis, osteotomies, interbody fusion and supplemental rod use. Postoperative alignment, complications, rod fractures, patient-reported outcomes (PROMs), cost of care (based on DRG reimbursements adjusted to 2021 US dollars), were evaluated at minimum 3-year follow-up, and cost/QALY calculated at 1-,2-, and minimum 3-year follow-up.
RESULT(S): Of 888 patients, 483 (mean 4.2 years follow-up, range 2.9 to 8.8) were evaluated. Mean BMP dosage was 27.6 mg total (range 1 to 200), 2.2 mg/level posterior (range 0 to 25) and 1.7 mg/level interbody (range 0 to 18). BMP (n=407) had similar demographics, osteotomies, total and interbody levels fused, preop PROMs, follow-up duration, and pre- and postoperative spinal alignment as NOBMP (n=76; p>0.05). BMP had fewer implant failures (0.17/patient vs 0.33/patient; p 0.05). At last follow-up, BMP had better SF-36 social function (46.7 vs 43.9) and SF-36 mental component scores (51.5. vs 47.8) than NOBMP (p <0.05, respectively). BMP had lower mean total cost of care/patient ($78,679.61 vs $103,388.78) and lower cost/QALY ($22,455.48 vs $32,947.68) at last follow-up vs NOBMP, respectively (p < 0.05). Revision surgery rates were similar for BMP vs NOBMP (0.32 vs 0.42/patient, p=0.11); however, costs of revision surgery were less for BMP ($11,114.33) vs NOBMP ($22,912.53, p <0.05).
CONCLUSION(S): Propensity score matched analysis demonstrated BMP use in ASD surgery at mean 4-year follow-up was associated with decreased implant fracture rates, lower treatment costs and better cost/QALY than NOBMP. Hospital systems, administrators and third-party payors should consider that the initial cost of BMP use at index surgery may be offset by decreased total cost of care and improve cost/QALY for ASD patients. FDA DEVICE/DRUG STATUS: Bone morphogenetic protein: Investigational.
Copyright

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.
Copyright

BACKGROUND CONTEXT: Previous literature has demonstrated the advantages of lateral single position surgery (L-SPS) in the perioperative period; however, 2-year postoperative outcomes of this novel technique have not yet been compared to circumferential anterior-posterior fusion (FLIP) at 2-years postoperatively. PURPOSE: Evaluate the feasibility and safety of L-SPS technique against the conventional FLIP. STUDY DESIGN/SETTING: Multi-center retrospective cohort study. PATIENT SAMPLE: Patients undergoing primary AP (ALIF or LLIF) fusions with bilateral percutaneous pedicle screw fixation between L2-S1 with minimum 2-year followup at three institutions. OUTCOME MEASURES: Outcome measures included levels fused, operative time, estimated blood loss and perioperative complications. Radiographic analysis included lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), PI-LL mismatch and segmental lumbar lordosis.
METHOD(S): Patients were grouped as L-SPS if anterior and posterior portions of the procedure were performed in the lateral decubitus position, and FLIP if patients were repositioned from supine or lateral to prone position for the posterior portion of the procedure. Groups were compared in terms of demographics, intraoperative, perioperative and radiological outcomes, complications and reoperations up to 2 years follow-up. Measures were compared using independent samples or paired t-tests and chi-squared analyses with significance set at p<0.05.
RESULT(S): A total of 442 pts met inclusion, including 352 L-SPS and 90 FLIP pts. Significant differences were noted in age (62.4 vs. 56.9; p= < 0.001) and smoking status (7% vs. 16%; p=0.023) between the L-SPS and FLIP groups. No differences between L-SPS and FLIP were noted in gender (57.4% female vs 57.8% female, p=1.000), BMI (30.0kg/m2 vs 29.3kg/m2; p=0.318). No differences were noted in number of levels fused between L-SPS and FLIP (1.45vs 1.50; p=0.533), proportion including ALIF (38% vs 39%; p=0.809), or the proportion of surgeries including L5-S1 (38%vs 31%; p=0.222). Perioperative outcomes: L-SPS demonstrated significantly lower Op time (97.7min vs 297.0 min; p < 0.001), fluoro dose (36.5mGy vs 78.8mGy; p < 0.001), EBL (88.8mL vs 270.0mL; p < 0.001), and LOS (1.91 days vs. 3.61 days; p < 0.001) compared to FLIP. L-SPS also demonstrated significantly fewer post-op complications than FLIP (21.9% vs 34.4%; p=0.013), specifically regarding rates of ileus (0.0% vs 5.6%; p < 0.001). There was no difference in remaining surgical site, neurological, or medical complications between groups. Reoperation: N=no differences in reoperation were noted at 30-day (1.7%L-SPS vs 4.4%FLIP, p=0.125), 90-day (5.1%L-SPS vs 5.6%FLIP, p=0.795) or 2-year follow-up (9.7%L-SPS vs 12.2%FLIP; p=0.441). The most common reason for return to OR was Adjacent Segment Disease, (L-SPS 3.1% vs. FLIP 7.8%; p=0.067). Pseudarthrosis rates were similar between groups (0.0%L-SPS vs. 1.1%FLIP; p=0.204). Radiological Outcomes: no significant differences were noted in rates of radiological fusion (94.3% L-SPS vs 97.8%FLIP; p=0.266) or subsidence (6.9%L-SPS vs 12.2%FLIP; p=0.260). There were no differences noted between L-SPS and FLIP in change in LL from Baseline to 1-year (3.5 vs 2.8; p=0.466) and post-op to 1yr (-0.18 vs -0.51; p=0.777), or in PI-LL from Baseline to 1-year (-3.5 vs -3.2; p=0.835) and from post-op to 1-year (0.71 vs 0.71; 0.998).
CONCLUSION(S): L-SPS improves safety, improves operative efficiency and reduces complications in the perioperative period while maintaining similar efficacy of AP fusion at 2-year followup in treating degenerative lumbar spinal conditions. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: Indirect decompression technique may be limited in that it does not include direct removal of the offending intervertebral disc or osteophyte protruding into the canal. PURPOSE: This study evaluates resolution of radiculopathy and perioperative complications in lumbar fusion with indirect or direct decompression techniques. STUDY DESIGN/SETTING: Retrospective analysis of large single center academic institution. PATIENT SAMPLE: This study included 116 single-level lumbar fusion patients with preoperative radiculopathy from 2012 to 2021. OUTCOME MEASURES: Resolution of radiculopathy, visual analog scores (VAS), perioperative complications, motor scores.
METHOD(S): Patients 18 years of age diagnosed with preoperative radiculopathy undergoing single-level lumbar fusion with up to two-year follow-up were grouped by indirect and direct decompression. Direct decompression group included TLIF with or without direct decompression procedure as well as ALIF and LLIF with direct decompression procedure. Indirect decompression group included ALIF and LLIF without direct decompression procedure. Propensity score matching (PSM) was used to control for differences in age between groups. Outcome measures were compared between groups using means comparison tests. Logistic regression analysis was used to correlate decompression type with symptom resolution over time.
RESULT(S): A total of 116 patients were included in this analysis: 58 direct decompression (mean 53.9y, 67.2% female) and 58 indirect decompression (mean 54.6y, 61.4% female). Direct decompression patients experienced greater blood loss relative to indirect decompression patients (242.4 +/- 128.5 vs 171.79 +/- 143.9 mL, p=0.007). Additionally, direct decompressionpatients experienced full resolution of radiculopathy at 3 months postop at a greater rate than those in the indirect decompression group (OR: 4.742, [1.97-11.41]; 53.1% vs 13.73%, p=0.002). At 6 months, direct decompression patients demonstrated a significantly larger reduction in VAS score 6 months postop (-2.889 +/- 2.3 vs -0.897 +/- 4.3, p=0.044). With regard to motor function, direct decompression patients had improved motor score with respect to the L5 dermatome at 6 months compared to indirect decompression patients (DELTAmotor score from baseline: 0.1714 +/- 0.453 vs -0.024 +/- 0.154, p=0.019).
CONCLUSION(S): Patients who underwent direct decompression experienced significantly greater resolution of preoperative lower extremity radiculopathy at 3 months compared with those who underwent ID alone. At 6 and 12 months, no differences were noted between the two groups. There were no differences in complication rates. At 6 months postop, direct decompression patients had greater improvement in preoperative motor deficit than ID patients. In particularly debilitated patients, these findings may influence surgeons to perform a direct decompression to achieve more rapid resolution of radiculopathy symptoms. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: Thoracic decompensation (TD) represents a distinct radiographic complexity from proximal junctional kyphosis (PJK). Few studies exist on the occurrence of TD following adult spinal deformity (ASD) corrective surgery. PURPOSE: To assess the incidence of TD following ASD-corrective surgery in comparison with the occurrence of PJK. STUDY DESIGN/SETTING: Retrospective cohort. PATIENT SAMPLE: A total of 689 ASD patients. OUTCOME MEASURES: ASD, TD, PJK, thoracic compensation.
METHOD(S): ASD patients with complete baseline (BL) and two-year (2Y) followup were included. Patients were divided into groups: those who developed TD: T4-T12 >54.2degree and those who developed PJK. Further analysis assessed outcomes among patients with both TD and PJK (TDPJK). Thoracic compensation was defined as expected thoracic kyphosis minus BL thoracic kyphosis. Means comparison tests and multivariable logistic regression analysis assessed differences between patient groups.
RESULT(S): A total of 373 patients met inclusion criteria. Patient breakdown by radiographic outcome was: TD (N=31), PJK (N=223) and TDPJK (N=119). Age, gender, and ASD-mFI were similar between TD and PJK patients. TD patients were more likely to be osteoporotic than PJK patients, p < 0.05. Procedures on TD patients were less invasive and utilized a shorter construct (9.3 vs 11.5 levels; both p < 0.05). TD patients had significantly greater cervical lordosis, thoracic kyphosis, and lumbar lordosis than PJK patients at BL and 2Y follow-up, all p < 0.05. Thoracic compensation was significantly associated with TD (OR 1.07 [CI 1.04-1.09], p < 0.001) controlling for age, ASD-mFI, and invasiveness. TDPJK had the highest complication rate (84.9%), significantly greater than PJK patients (70.9%), and TD patients (61.3%), both p < 0.05. PJK patients were 78.7% less likely to develop PJF than TDPJK patients (OR 0.213 [CI 0.101-0.453], p < 0.001).
CONCLUSION(S): Patients who developed thoracic decompensation were more likely to present with osteoporosis, but had less invasive procedures and levels fused than patients with proximal junctional kyphosis. The tradeoff between fusing too much resulting in proximal junctional kyphosis and fusing too little predisposing to thoracic decompensation can serve as the basis of future studies to determine optimal construct length to balance these two risks. Thoracic compensation was predictive of postoperative thoracic decompensation in adult spinal deformity-correction. Patients who developed TDPJK had the highest rate of complications and greater odds of junctional failure. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: Prophylaxis usage has been established in literature as an important component of minimizing the risk of proximal junctional kyphosis (PJK) and proximal junctional failure (PJF) development. However, literature is scarce on the effects of prophylaxis in patients who have achieved adequate postoperative alignment and those who maintained poor alignment postoperatively. PURPOSE: To investigate how PJK prophylaxis impacts rates of PJK and PJF with and without ideal alignment and the associated cost/cost-effectiveness. STUDY DESIGN/SETTING: Retrospective cohort study of a prospective adult thoracolumbar deformity database. PATIENT SAMPLE: This study included 1,541 patients. OUTCOME MEASURES: Radiographic alignment, patient-reported outcome measures (ODI), cost per QALY.
METHOD(S): Operative adult spinal deformity patients (scoliosis >20degree, SVA>5cm, PT>25degree, or TK>60degree) with an UIV at L1 or below and available baseline (BL) and 2-year (2Y) radiographic and HRQL data were included. "Matched" and "unmatched" alignment refers to the age-adjusted alignment criteria. PJK prophylaxis was defined by usage of cement, hooks or tethers. PJF was defined as PJK with reoperation. Costs were calculated using the PearlDiver database, accounting for additional costs of prophylaxis when applicable, through estimates from Medicare pay scales for services within a 30-day window, including estimates regarding costs of postoperative complications, outpatient healthcare encounters, revisions and medical related readmissions. QALY was calculated using SF6D.
RESULT(S): A total of 738 ASD patients or below met inclusion criteria (59.9yrs+/-14.0, 79%F, BMI: 27.7 kg/m2 +/-6.0, CCI: 1.8 +/-1.7). Surgically, patients had a mean level fused of 11.1+/-4.4, LOS of 7.9 days+/-4.4, EBL of 1577 mL, operative time of 377 min, with 63% undergoing an osteotomy. Forty percent of patients had PJK prophylaxis. Controlling for age, CCI, BL osteoporosis, levels fused, usage of 3CO, UIV, BL SVA and BL PI-LL, patients who were matched postoperatively in PT, SVA, or PI-LL had lowered PJF rates (OR:.5, 95% CI:.28-.86, p=.01) with prophylaxis. Among those unmatched in either SVA, PILL, or PT by 6W, prophylaxis significantly reduced the rates of PJK and PJF as well (p <0.05). ANCOVA controlling for age, CCI, BL osteoporosis, levels fused, usage of 3CO, UIV, BL SVA and BL PI-LL shows patients with ideal age-adjusted alignment and prophylaxis resulted in a lower cost per QALY by 2Y ($399,948 vs $514,228, p <.001). Similarly, in unmatched patients, prophylaxis resulted in a substantially lower cost per QALY by 2Y ($466,409 vs 672, 024, p <.001), primarily due to decreased costs of reoperation and greater improvements in QALY among prophylaxis cohorts.
CONCLUSION(S): Despite additional surgical cost, optimization of radiographic realignment in conjunction with utilization of proximal junctional failure prophylactic techniques achieves ideal cost utility, predominately due to the minimization of mechanical failure related reoperations. Even among those not achieving optimal alignment, junctional prophylactic measures improved cost utility, emphasizing its critical role of minimization of junctional failures to achieve cost efficiency in adult spinal deformity surgery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: The ACS-NSQIP and SpineSage are both easy to use and readily available online perioperative risk calculators The ACS-NSQIP calculator predicts perioperative complications after surgery, but lacks more spine-specific predictors. The SpineSage platform was developed as a tool built for predicting complications in spine surgery. While a limited number of studies have shown it be predictive of both overall and major medical complications in spine surgery, large external validation studies are limited and none have directly compared NSQIP against SpineSage in the same cohort of spine surgery patients. PURPOSE: Assess the ACS-NSQIP Risk Calculator and SpineSage informatics platform for prediction of perioperative complications in spine surgery STUDY DESIGN/SETTING: Retrospective. PATIENT SAMPLE: A total of 440 patients undergoing thoracolumbar spine with or without fusion. OUTCOME MEASURES: Any complication, serious complication, pneumonia, cardiac, dural tear, SSI, UTI, VTE, reoperation, death and LOS METHODS: Each patient was entered into the ACS-NSQIP and SpineSage calculators and predicted risk for specific complications were directly compared to actual risks. Paired t-tests compared the differences between calculators and their predictability of complications. Patients were ranked based on risk predicted for each complication and the highest tertile for each was isolated. Multivariate regression controlling for age and gender was used to determine if the highest tertile for each risk calculator had predictability in complications following spine surgery.
RESULT(S): Mean LOS 4.2+3 days, EBL 444+300 mL, operative time 256+240 min, and levels instrumented 2.1+2.3. When assessing the four complications predicted by SpineSage there were significant differences in three of the four variables, as SpineSage underpredicted the risk of all and serious-complications (p.5). Both calculator tertiles were trending towards significance for major medical complications (SpineSage: OR: 2.0, [0.94-4.23], p=.073; ACS-NSQIP: OR: 1.8,[0.96-3.48],p=.067). When examining any medical risk, only ACS NSQIP had significant predictability for any medical complication (OR: 2.1, [1.3-3.3]; p=.003).
CONCLUSION(S): Similar to previous studies, the ACS-NSQIP score underpredicted most complications, with the exception of LOS and death. In contrast to previous studies, our data suggest SpineSage was not predictive of actual rates of complications. As both calculators are highly accessible and provide at least some objective perioperative risk data points, we recommend them as a guiding tool but not as an absolute endpoint for clinical decision making as they may be inaccurate and insensitive. Further, higher powered studies elucidating the findings in this study should be conducted. Additionally, the assessment of these calculators for a specific subset of patients, such as deformity, degenerative or pediatrics, can further help guide clinicians regarding the utility of these calculators for their particular patient populations. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: Previous reports indicate postoperative complications have minimal impact on long-term outcomes after ASD surgery. Little data has evaluated the impact of complications on specific heath domains during postoperative period. PURPOSE: To evaluate the impact of specific complications on patient reported health domains compared to patients with no complications. STUDY DESIGN/SETTING: Prospective, multicenter, propensity score matched analysis. PATIENT SAMPLE: ASD patients enrolled into a prospective multi-center study. OUTCOME MEASURES: Oswestry Disability Index, Scoliosis Research Society-22r questionnaire (SRS-22r), Short Form-36v2 questionnaire (SF-36), postoperative complications.
METHOD(S): Surgically treated ASD patients enrolled into a multicenter study were assessed for postoperative complications requiring surgery including wound (WOUND), pseudoarthrosis (PSEUDO), neurologic (NEURO) and malalignment (MAL) and matched to patients with no complications (NOCOMP) using inverse probability weighting for demographic, radiographic and surgical variables. Health domains for SRS-22r, and SF-36 were evaluated at regular time intervals, domain scores normalized to the date of revision surgery, and compared to patients with no complications at minimum 2-year follow-up.
RESULT(S): A total of 566 of 1130 were analyzed, average 3.6 yrs (range: 1.9 to 9). WOUND (n=12) compared to NOCOMP (n=390) had worse SF-36 physical function(21.7 vs 27.4), social function(19.6 vs 28.9), general health (-7.3 vs 8.9) and vitality (-0.9 vs 26.6,p < 0.05). PSEUDO (n=64) was worse than NOCOMP for SRS-22r function, 1.4 vs 2.1, and SF-36 social function, (17.1 vs 28.9) (p < 0.05). NEURO (n=28) was worse than NOCOMP for SRS-22r (0.9 vs 2.1), SF-36 bodily pain (14.7 vs 35.7) and social function (13.4 vs 28.9) (p < 0.05). MAL (n=72) was worse than NOCOMP for SRS-22r pain, (2.7 vs 3.4), function (1.2 vs 2.1), self-image (3.0 vs 3.9), SF-36 bodily pain (27.6 vs 35.7), physical function (18.7 vs 27.4), and social function (11.6 vs 28.9) (p < 0.05).
CONCLUSION(S): Counter to previous reports, specific postoperative complications requiring surgery uniquely impact specific health domains, resulting in worse patient reported quality of life compared to ASD patients with no complications. Social function was negatively impacted for all complications, while wound complications negatively impacted patient perceived general health and vitality and patients with malalignment requiring surgery reported worse self-image. These data highlight new findings that postoperative complications have a negative impact on specific aspects of ASD quality of life that can undermine the potential benefits of ASD surgery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: Numerous studies have reported the interplay between spinal deformity and pelvis compensatory mechanisms, but little data exist evaluating the contribution of lower extremity compensation (LE) to maintain upright posture. We hypothesis that hip, knee and ankle compensation is proportional to the severity of the spinal deformity and varies by demographics. PURPOSE: Evaluate the association between spinal alignment and lower limbs compensation. STUDY DESIGN/SETTING: Multicenter, prospective cohort. PATIENT SAMPLE: This study included 288 patients treated for complex adult spinal deformity (ASD) with full body images available. OUTCOME MEASURES: Pelvic retroversion (PT), hip extension (SFA), knee flexion (KA), ankle dorsiflexion (AA), pelvic translation (P.Shift) and patient reported outcomes (ODI, PROMIS and SRS-22).
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). Associations between lower extremity compensation (hip extension, knee flexion, and ankle dorsiflexion) and the magnitude of spinal deformity, patient demographics, patient frailty, and patient-reported outcomes (ODI, SRS, PROMIS-CAT) were assessed via regressions and partial correlations.
RESULT(S): A total of 288/329 patients met inclusion criteria (60+/-15yo, 70.5% female), had moderate to severe spinal deformity (PI-LL:15+/-24, TPA:24+/-14, SVA:65+/-69mm, lumbar Cobb:34+/-24), and reported high pain (PROMIS pain interference; PI=62.7+/-7.8) and reduced physical function (PROMIS physical function; PF=35.6+/-7.6). Lower extremity compensation included pelvic retroversion (PT:24.1+/- 11.8), hip extension (SFA: 203+/-10.5), knee flexion (KA:5.5+/- 9.6), ankle dorsiflexion (AA: 5.3+/-4.5), and posterior pelvic translation (P.Shift: 30+/-51mm). Overall, lower extremity compensation increased with age (all p <0.001), BMI and frailty (all p <0.001, except SFA). For a similar PT, women had greater hip extension than men (SFA: 206 vs 200, p <0.001), with less KA (3.6 vs. 10.1, p <0.001), AA, and P.Shift. Lower extremity compensation increased with PI (r=0.2-0.45, p <0.001), TPA (r=0.5-0.9, p <0.001) and correlated with PROMS (ODI:0.26 - 0.37, PROMIS PF: -0.28 - -0.39, SRS Acti.: -0.20 - -0.33). When controlling for deformity severity and PI, most associations between lower limbs compensation and PROMS were lost. However, P.Shift and SFA remained weakly correlated with physical scores (ODI and PROMIS PF).
CONCLUSION(S): The recruitment of LE compensation is overall proportional to the severity of adult spinal deformity, with different patterns observed between men and women. Patients achieved similar PT by recruiting different patterns of LE compensation. Hip extension and posterior pelvic translation are independently associated with impairment in patient-reported outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright

BACKGROUND CONTEXT: Evidence on long-term maintenance of health status in adult spinal deformity (ASD) patients who improve above MCID threshold (MCID+) at 2 years following surgery is limited. PURPOSE: This study aims to: (1) evaluate whether patients who reached MCID+ status at two years postoperatively will maintain MCID+ status at 5 years, (2) identify risk factors associated with maintaining MCID+ status, and (3) Assess whether maintaining MCID+ status at 5 years is associated with satisfaction with surgery. STUDY DESIGN/SETTING: Retrospective review. PATIENT SAMPLE: Patients who underwent adult spinal deformity (ASD) surgery with minimum 5-year follow-up who achieved 2-year MCID in ODI were identified. OUTCOME MEASURES: Maintenance of MCID+ status at 5 years for Oswestry Diability Index (ODI).
METHOD(S): Patients who maintained MCID+ status at 5 years and those who did not formed the comparison groups. Multivariable logistic regression, controlling for age, complications after two years and two-year alignment, was used to identify risk factors associated with the inability to maintain MCID+ status. In a separate multivariable logistic regression, whether maintaining MCID+ status was associated with 5-year surgical satisfaction was assessed.
RESULT(S): Of 633 eligible patients, 339 had 5-year data. Of 133 with both 2- and 5-year data, 70 who achieved 2-year MCID in ODI were included. 30% (21) failed to maintain MCID+ status at 5 years. Preoperatively, 33% (23) were narcotic users, 47% (33) were frail and mean surgical invasiveness was 96.6+/-36.02. On multivariable logistic regression, preoperative variables were assessed: CCI > 3 (OR 5.75; p=0.026), ASA grade > 2 (OR 5.25; p=0.015), anemia (OR 19.74; p=0.009), and cancer (OR 6.46; p=0.015) were associated with increased odds of failure to maintain MCID+ status at 5-year follow-up. Patients who failed to maintain MCID+ status at 5 years had a higher odds of being unsatisfied with the surgery (OR 15.66; p=0.001). Frailty and surgical invasiveness had no significant impact on MCID+ status at 5 years.
CONCLUSION(S): Preoperative comorbid conditions significantly impact patient's long-term ability to maintain the positive gains in health-related quality of life measures from the surgery. Surgeons should continue to monitor and treat the chronic conditions to ensure maintenance of long-term recovery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
Copyright