Faculty Bibliography

BACKGROUND CONTEXT: Recent studies have suggested that for patients with chronic neck pain, both psychological and physical symptoms need to be addressed. Studies have shown that psychological distress is associated with poor outcomes in these patients. The fear avoidance model has been used to explain how maladaptive thoughts and behaviors contribute to chronicity and disability. Cognitive behavioral therapy (CBT) addresses these risk factors through education about pain, modification of maladaptive beliefs, and increasing patient's self-efficacy. PURPOSE: Determine the effectiveness of brief psychological intervention on psychological outcomes in cervical spine surgery. STUDY DESIGN/SETTING: Prospective, blind, and placebo-controlled trial. PATIENT SAMPLE: A total of 42 symptomatic Cervical Degenerative Disorders patients. OUTCOME MEASURES: Distress and Risk Assessment Method (DRAM), Fear Avoidance Beliefs Questionnaire (FABQ), Pain Catastrophizing Scale (PCS), Outcome Expectation Question (OEQ). Neck Disability Index (NDI), modified Japanese Orthopedic Association (mJOA).
METHOD(S): Forty-two patients age >18 with symptomatic cervical degenerative disease have been enrolled in the study. If patients met psychological distress criteria, they were in the treatment group: DRAM >17 and <33, FABQ >49/66, PCS >30/52 or OEQ <=2 (randomized to CBT or Placebo). CBT and Placebo treatment groups had 6 sessions prior to surgery. The control group had no intervention prior to surgery. Baseline and 1-year (1Y) changes were assessed for all outcome measures.
RESULT(S): Forty-two patients were enrolled (53.6 years, BMI 29.4 kg/m2); 23 patients met psychological distress criteria and were randomized into a treatment group (14 CBT vs 9 placebo). Ten patients were in the control group, with nine exceeding DRAM scores to be CBT candidates. At enrollment, the CBT group had greater EQ5D scores (CBT: 10.8, Placebo: 9.5, Control: 7.5, DRAM:8.7) while the Placebo group had greater PCS scores (Placebo: 33.1, CBT: 32.4, Control:18.6, DRAM: 30.8; all p<0.05). From BL to 1Y postop, the CBT patients improved in all psychological-related questionnaires (NDI: 29.2 to 2, PCS: 32.4 to 20.7, FABQ:41.3 to 32.3, mJOA: 2.3 to 3.4, DRAM:12.9 to 16.6). Placebo patients also improved post-operatively, but to a lesser degree in NDI (26.6 to 2), PCS (33.1 to 28.3), and worsened in FABQ (40.4 to 54.1), mJOA(12.5 to 11.8), and DRAM (36.6 to 31.6). In contrast, patients in the control group showed improvement to a much lesser degree than CBT and Placebo patients (NDI: 18.1 to 2, PCS:18.6 to 3.2, FABQ:26.2 to 17.6, mJOA: 15.3 to 16.4). DRAM patients showed minimal changes in psychological- and spine-related questionnaires. Comparing treatment groups at 1Y, CBT pts had significantly lower FABQ scores than Placebo pts (32.3 vs 54.1; p<0.05). CBT pts also had better DRAM scores than the control group at 1Y (30.3 vs 11.4; p=0.03).
CONCLUSION(S): Cognitive behavior treatment can be beneficial in patients undergoing cervical surgery as it was identified in our study to minimize fear avoidance beliefs more than the Placebo group. This type of professional treatment has also shown a steady improvement in all psychological questionnaires and spine related neck disability from baseline to 1-year postoperatively. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Recombinant human bone morphogenetic protein 2 (BMP) is increasingly utilized in minimally invasive (MIS) transforaminal lumbar interbody fusions (TLIF) in order to increase rate of fusion by promoting bone growth through the induction of osteoblast differentiation, awhile reducing morbidity related to iliac crest autograft. Despite these benefits, BMP use is still controversial due to its pro-inflammatory mechanism of action and potential to cause radiculitis. PURPOSE: To assess whether BMP is a risk factor for postoperative radiculitis in TLIF. STUDY DESIGN/SETTING: Single-center retrospective cohort study. PATIENT SAMPLE: A total of 397 TLIFs from June 2012 to December 2018. OUTCOME MEASURES: Perioperative clinical characteristics, post-operative risk of radiculitis and complication, and future reoperation rates.
METHOD(S): Patients >= 18 years-old undergoing elective single-level TLIFs from 2012 to 2018 were included. Outcome measures included perioperative clinical characteristics, postoperative risk of radiculitis and complication, and future reoperation rates. Radiculitis was defined the delayed onset of radicular symptoms postoperatively in patients whom had initial resolution of radicular symptoms immediately postoperatively, in the absence of persistent neurological compression on postoperative imaging. Statistical analyses included independent t-tests and chi-square analysis. Propensity score matching was utilized to control for demographic differences between the groups. Independent predictors for post-operative radiculitis were assessed by multivariate logistic regression. Significance set at p<0.05.
RESULT(S): A total of 397 cases were included in the study (59.33 +/- 13.49 mean age, 28.98 +/- 6.29 mean BMI, 52.90% female, 2.29 +/- 1.92 average Charleston comorbidity Index). There were 223 open procedures and 174 MIS. For the entire cohort, 238 cases utilized BMP and 159 did not, with 102 MIS pairing with BMP use. The MIS TLIFs had a higher percentage of BMP use than open TLIFs (58.6% vs 25.7%, p<0.001), lower estimated blood loss (212.28 +/- 193.79 mL vs 410.91 +/- 337.98 mL, p<0.001) higher fluoroscopy dosage (52.43 +/- 48.61mGy vs 16.77 +/- 27.84mGy, p<0.001), and a lower length of stay (3.20 +/- 2.55 days vs 4.11 +/- 2.52 days, p<0.001). There were no other differences in perioperative clinical characteristics. There was a significantly higher rate of postoperative radiculitis in the MIS TLIFs compared to open (12.6% vs 6.8%, p=0.046) and use of BMP compared to no BMP (13.2% vs 6.7%, p=0.029). There was a 15.7% radiculitis rate when MIS was paired with BMP use. There were no other notable differences in complication rates or rates of reoperation. Individually, MIS had a 12.6% radiculitis rate (p=0.046) and BMP use had a 13.2% rate (p=0.029). Propensity score match controlled for the significant difference in CCI between the MIS and open groups (N=168 each). Multivariate regression indicated that MIS (p=0.314) and BMP (p=0.109) were not independent predictors individually when controlling for age, gender, and BMI. When technique was paired with biologic use the regression revealed MIS + BMP is a risk factor of post-operative radiculitis (2.265(4.753-1.079), p=0.031).
CONCLUSION(S): While BMP and MIS technique were not independent risk factors for postoperative radiculitis, there is an increased risk of radiculitis when using BMP in MIS TLIF. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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Metabolic syndrome is a clustering of clinical findings defined in the literature including hypertension, high glucose, abdominal obesity, high triglyceride, and low high-density lipoprotein cholesterol levels. The purpose of this study was to assess perioperative outcomes in patients undergoing spine fusion surgery with (MetS) and without (no-MetS) a history of metabolic syndrome. Included: Patients ≥18 yrs old undergoing spine fusion procedures diagnosed with MetS components with BL and 1-year follow-up were isolated in a single-center database. Patients in the two groups were propensity score matched for levels fused. 250 spine fusion patients (58 yrs, 52.2%F, 39.0 kg/m²) with an average CCI of 1.92 were analyzed. 125 patients were classified with MetS (60.2 yrs, 52%F, CCI: 3.2). MetS patients were significantly older (p = 0.012). MetS patients underwent significantly more open (Met-S: 78.4% vs No-MetS: 45.6%, p < 0.001) and posterior approached procedures (Met-S: 60.8% vs No-MetS: 47.2%, p = 0.031). Mean operative time: 272.4 ± 150 min (MetS: 288.1 min vs. no-MetS: 259.7; p = 0.089). Average length of stay: 4.6 days (MetS: 5.27 vs no-MetS: 3.95; p = 0.095). MetS patients had more post-operative complications (29.6% vs. 18.4%; p = 0.038), specifically neuro (6.4% vs 2.4%), pulmonary (4% vs. 1.6%), and urinary (4.8% vs 2.4%) complications. Binary logistic regression analyses found that MetS was an independent risk factor for post-operative complications (OR: 1.865 [1.030-3.375], p = 0.040). With longer surgeries and greater open-exposure types, MetS patients were at greater risk for complications, despite controlling for total number of levels fused. Surgeons should be aware of the increased threat to spine surgery patients with metabolic syndrome in order to optimize surgical decision-making.

BACKGROUND CONTEXT: The Roussouly Classification system of sagittal spinal shape and the SRS-Schwab adult spinal deformity (ASD) classification system have become important indicators of spine deformity. No prior studies have examined the outcomes of matching both Roussouly type and improving in Schwab modifiers postoperatively. PURPOSE: Evaluate outcomes of matching Roussouly Type and improving in Schwab modifier following ASD surgery. STUDY DESIGN/SETTING: Retrospective review of single-center ASD database. PATIENT SAMPLE: A total of 103 ASD patients. OUTCOME MEASURES: Roussouly types, Schwab modifiers, Health Related Quality of Life scores(HRQLs): Minimal Clinical Important Difference for ODI, EQ5D, VAS Leg &Back Pain.
METHOD(S): Surgical ASD patients (SVA>=5cm, PT>=25degree, or TK >=60degree, >3 levels fused) >=18 years old with available baseline (BL) radiographic data at baseline (BL) and 1-year (1Y) were isolated in the single-center Comprehensive Spine Quality Database (Quality). Patients were grouped by two Roussouly types: (1)"theoretical" Roussouly type(Type 1: PI<45degree, LL apex below L4; Type 2: PI<45degree, LL apex above L4 L4-L5 space; Type 3: 45degree60degree); (2) "current" Roussouly type (1: SS<35degree, LL apex below L4; 2: PI<35degree, LL apex above L4-L5 space; 3: 35degree45degree), as previously published. One year (1Y) matched Roussouly: preoperative mismatched (Between 'actual' and 'theoretical' patients that matched at 1Y. Schwab modifiers at BL were identified: non-, moderate and severe deformity (0, +, ++) for PT, SVA, and PI-LL. Schwab improvement was defined as a decrease in a modifier at one year.
RESULT(S): A total of 103 ASD patients (61.8yrs, 63.1%F, 30kg/m2). By surgical approach, 79.6% posterior, 10.7% combined, 2.9% anterior). Average levels fused: 4.6. BL breakdown of 'current; Roussouly type: 28% Type 1, 25.3% Type 2, 32.0% Type 3, 14.7% Type 4. BL Roussouly mismatch: 65.3%. Breakdown BL Schwab modifiers: PT (0: 8.7%, +: 41.7%, ++: 49.5%), SVA (0: 29.7%, +: 20.3%, ++: 50%), PI-LL mismatch (0: 28.2%, +: 25.2%, ++: 46.6%). At one year, 19.2% of patients matched Roussouly target type, while according to Schwab modifiers, 12.6% improved in SVA, 42.7% in PI-LL, and 45.6% in PT. Patients who both met Roussouly type and improved in a Schwab by the modifiers: 9 PT (8.7%), 8 PI-LL (7.8%), 2 SVA (1.9%). There were 2 patients (1.9%) who met their Roussouly type and improved in all 3 Schwab modifiers. One year (1Y) matched Roussouly patients improved more in HRQLs (MCID for ODI, EQ5D, VAS Leg/Back Pain), when compared to mismatched Roussouly, but was not significant(P>0.05). Match Roussouly and improvement in PT Schwab met MCID for EQ5D significantly more (33.3% vs 10.6%, p=0.050). Matched Roussouly and PI-LL Schwab had more patients meet MCID for all HRQLs, yet none were significant, p>0.05. Matched Roussouly and improvement in SVA Schwab met MCID for ODI significantly more (p=0.024).
CONCLUSION(S): Patients who both matched Roussouly sagittal spinal type and improved in SRS-Schwab modifiers had superior patient-reported outcomes at 1-year. Utilizing both classification systems in surgical decision making can optimize postop patient outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Persistent lumbopelvic malalignment following ASD-corrective surgery may impair quality of life and result in persistent pathologic compensation in the lower extremities. Patient-specific age- and BMI-adjusted alignment targets have been proposed to improve alignment outcomes; however, it is unclear whether reaching these postop targets reduces rates of pelvic nonresponse following surgery. PURPOSE: Assess the relationship between pelvic nonresponse to ASD-corrective surgery and persistent lower-extremity compensation. STUDY DESIGN/SETTING: Single center retrospective review. PATIENT SAMPLE: Fifty-eight ASD patients. OUTCOME MEASURES: Sagittal alignment.
METHOD(S): Included: surgical ASD patients with full-spine X-ray imaging at pre- and early postop follow-up (<1Y). Patients were grouped by postop improvement in PT, per SRS-Schwab Classification: those who did not improve (pelvic nonresponders, PNR), and those that did improve (pelvic responders, PR). Groups were propensity score matched for preop PT, and assessed for differences in demographics, surgical factors, and alignment (sagittal spinal and lower extremity) with means comparison tests. Rates of persistent postop lower extremity compensation (defined as no improvement in lower extremity alignment) were compared between groups. Subanalysis assessed the relationship between reaching postop age- and BMI-specific alignment targets and rates of pelvic nonresponse.
RESULT(S): Following propensity score matching, PNR (N=29) and PR (N=29) patients did not differ in age, sex, BMI or preop sagittal spinal alignment (all p>0.05); however, PNR patients presented with less knee flexion (9degree vs 14degree, p=0.043). Groups did not differ in levels fused (10.8 vs 10.8, p=0.974) or osteotomy (93% vs 92%, p=0.902). Postop, PNR patients had inferior lumbopelvic alignment in PT (30degree vs 17degree), PI-LL (17degree vs 3degree), and greater global malalignment for TPA (27degree vs 15degree, all p<0.001). For PNR patients, these changes in alignment were accompanied by greater compensatory anterior hip extension (53mm vs 31mm, p=0.021). PNR patients also showed greater pre- to postop increases in sacrofemoral angle (2degree vs -5degree), and smaller decreases in hip extension (-24mm vs -64mm), pelvic femoral angle (-1.4degree vs -3.8degree), and global sagittal angle (-3.5degree vs -8degree, all p<0.005), indicating persistent lower extremity compensation. PNR patients had higher rates of persistent postop lower extremity compensation for sacrofemoral angle (68% vs 25%), ankle flexion (64% vs 33%), and pelvic shift (28% vs 4%, all p<0.034). PNR and PR groups did not differ in rates of reaching age- and BMI specific ideal postop alignment for PT, SVA, TPA, or PI-LL (all p>0.05). For patients with severe preop SVA deformity, overcorrection relative to ideal postop PT targets was associated with lower rates of pelvic non-response (under: 12%, match: 18%, over: 71%, p<0.001). Lower rates of nonresponse were observed for patients with severe preop PT deformity overcorrected relative to ideal postop PI-LL (under: 0%, match: 30%, over: 70%, p=0.016).
CONCLUSION(S): Pelvic nonresponders following ASD-corrective surgery had higher rates of persistent compensatory action in the lower extremities. Patients with severe preop PT deformity who were surgically overcorrected with respect to ideal PI-LL had lower rates of postop pelvic nonresponse, indicating that for severely malalignmed patients, existing alignment targets may need to be adjusted to optimize alignment outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: In the current value-based health care climate where spinal surgery is shifting to the ambulatory setting, factors influencing postoperative patient length of stay (LOS) have significance to both surgeons and hospital administrators. Underlying patient factors including the diagnosis of radiculopathy and myelopathy have not been investigated in this context. PURPOSE: Identify predictors extended LOS(E-LOS) between myelopathy(M), radiculopathy(R), and patients with both (MR). STUDY DESIGN/SETTING: Retrospective review of a single-center stereographic database. PATIENT SAMPLE: A total of 718 surgical cervical spine patients. OUTCOME MEASURES: Postoperative LOS, patient factors, preoperative HRQL, complications, predictors of E-LOS.
METHOD(S): Surgical cervical spine patients >=18yrs diagnosed with M or R primary diagnoses were isolated in the single-center Comprehensive Spine Quality Database (Quality). Patients were stratified by surgical approach: Anterior, Posterior or Combined. Top-quartile LOS values were labeled as extended. M and R patients were compared using chi-squared and independent samples t-tests, as appropriate. Univariate tests assessed differences in baseline patient-related and surgical data between M and R, and extended/non-extended LOS. Univariate/multivariate analyses were run to assess predictive factors of E-LOS in each diagnosis group. Regression with stepwise model selection was employed to explore factors potentially significant in predicting LOS.
RESULT(S): A total of 718 patients (54.5 years, 41.1%F, 29.1kg/m2). Mean CCI score: 1.11. Within the cohort, 177 patients (24.7%) had a diagnosis of myelopathy, 383 (53.3%) radiculopathy, and 22% with a diagnosis of myeloradiculopathy. Patients with M primary diagnosis were significantly older (62.2 vs 49.8yrs, p<0.001) and had a greater CCI score (1.64 vs 0.82, p<0.001) when compared to R patients. By approach: 76.7% anterior (57.6% of M, 90.6%R, 64.6%MR; p<0.001), 16.4% (35%M, 6%R, 20.9%MR; p<0.001) posterior, 6.5% (6.8%M, 3.4%R, 13.9%MR; p<0.001) combined. Average LOS: M(3.8days), R(1.5 days), MR(2.9 days) p<0.001. LOS for anterior approach in each diagnosis was as follows, M: 2.21, R: 1.21, MR: 1.69 days, p<0.001. Meanwhile, posterior approach LOS, M:6.06, R:2.91, MR:5.0, p<0.001; combined approach M: 5.17, R: 6.23, MR: 5.59, P=0.881. A total of 195 patients were categorized as E-LOS (Avg: 5.87 days), 87 M, 43 R, 65 MR. Major surgical approach of E-LOS for M (60.9%) and MR (44.6%) was posterior; whereas R E-LOS patients majorly underwent anterior procedures (53.5%). Generalized linear regression modeling found that the following combination of factors predicted E-LOS in R patients (R2=0.736, p=0.003):BMI, durotomy, CCI, anterior and combined approaches, and cardiac complications. An additional model discovered the predictors of E-LOS in M patients (R2= 0.312, p<0.001): age, hypertension, CCI, anterior and combined approaches, intraoperative complications, neuro complications, ileus, and return to OR in 90 days. Lastly, the model for E-LOS in MR patients consisted of (R2 = 0.267, p=0.001): age, durotomy, BL EQ5D, hypertension, posterior and combined approaches and postoperative complications, specifically neuro.
CONCLUSION(S): Independent of surgical approach, patients with a primary diagnosis of myelopathy, though older aged and higher comorbidity profile, had consistently longer overall postop LOS when compared to radiculopathy or myeloradiculopathy patients. The heightened risk in myelopathy patients for extended LOS should be considered when determining admission status for patients undergoing cervical spine surgery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The Adult Spinal Deformity Frailty Index (ASD-FI), a validated modality for quantifying frailty, stratifies patients into categories not frail (NF), frail (F) and severely frail (SF). However, the cost of treating each frailty state is unknown. PURPOSE: Investigate the cost utility of treating not frail versus frail or severely frail ASD patients. STUDY DESIGN/SETTING: Retrospective review of a prospective single center adult spinal deformity database. PATIENT SAMPLE: A total of 79 operative and non operative ASD patients >=18 years old, with baseline and 2Y ASD-FI and Oswestry Disability Index (ODI) scores. OUTCOME MEASURES: ODI, SF-6D, Cost per quality adjusted life years (QALY), Incremental Cost Effectiveness, Ratio (ICER).
METHOD(S): Inclusion criteria was surgical ASD (scoliosis>=20degree, SVA>=5cm, PT>=25degree, or thoracic kyphosis >=60degree) patients >18 years with available frailty and ODI data at BL and 2-years post op. Independent T-Tests assessed baseline radiographic differences in PT, PI-LL, and Schwab SVA modifier status between NF vs. F/SF patients. Utility data was calculated using the ODI converted to the SF-6D using published conversion methods. QALYs utilized a 3% discount rate to account for residual decline to life expectancy (78.7 years). Costs were calculated using the PearlDiver database. After accounting for complications, LOS, revisions, and death, cost per QALY at 2Y and life expectancy were calculated for NF, and F/SF patients. ICER was compared between non op and operative NF and F/SF patients at 2Y and life expectancy.
RESULT(S): Seventy-nine ASD patients met inclusion criteria. Descriptive statistics for the cohort were: age 51.0+/-6.8, 76% women, BMI 26.7+/-6.8, 54% osteotomy, 54% decompression, and 11.6+/-4.2 average levels fused. At BL, there were 48 NF, 26 F, and 4 SF pts. The average BL frailty for NF pts was 0.13+/-0.08, 0.39+/-0.06 for F, and 0.59+/-0.08 for SF pts. There were no differences in PT, PI-LL, or severe SVA Schwab modifier grades between NF or F/SF pts (all p>0.05). At 2-year follow up, there was no difference in the average cost of ASD surgery, $91,068.98 for NF patients and $90,888.53 for F/SF pts (p>0.05). The cost per QALY was higher for NF pts at 2 years vs F/SF pts ($464,239.62 vs. $321,107.89, p<0.05). If the utility gained was sustained to life expectancy, the cost per QALY was $70,796.43 for NF and $48,968.88 for F/SF (p<0.05). When compared to non op ASD pts, the ICER was $447,943.96 vs. $313,211.01 for NF and F/SF at 2 years, and $68,311.35 vs. $47,764.61 for NF and F/SF at life expectancy.
CONCLUSION(S): Frail and severely frail patients had lower cost per QALY compared to not frail patients at 3 years and life expectancy. In addition, when compared to a non operative cohort of ASD patients, frail and severely frail patients had lower ICER values. While these results support operative correction of frail and severely frail patients, it is important to note that these patients are often at worse baseline disability, which is closely related to frailty scores, and have more opportunity to improve postoperatively. In addition, there may be a threshold of frailty that is not operable due to the risk of severe complications that is not captured by this analysis. While future research should investigate economic outcomes at extended follow-up times, these findings support the cost effectiveness of ASD surgery at all frailty states. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Numerous advances have been made in the field of spine fusion, such as minimally invasive (MIS) or robotic assisted spine surgery. However, it is unknown how these advances have impacted the cost of care. PURPOSE: Compare the economic outcomes of lumbar spine fusion between open, MIS and robotic assisted surgery patients. STUDY DESIGN/SETTING: Retrospective review of a single center spine surgery database. PATIENT SAMPLE: A total of 360 propensity matched patients. OUTCOME MEASURES: Costs, EuroQol-5D (EQ5D), Cost per quality adjusted life years (QALY).
METHOD(S): Inclusion criteria: surgical patients >18 years undergoing lumbar fusion surgery. Patients were categorized into 3 groups based on procedure type: open, MIS or robotic. Open patients undergoing poster spinal fusion were considered as the control group. MIS patients included those undergoing transforaminal or lateral lumbar interbody fusion with percutaneous screws. Robotic patients were those undergoing robot assisted fusion. Propensity score matching was performed between all groups for the number of levels fused. Costs were calculated using the PearlDiver database, which reflects both private insurance and Medicare reimbursement claims for ICD-9 codes. For robot cases, costs were reflective of operational fees and initial purchase cost. Complications and comorbidities (CC) and major complications and comorbidities (MCC) were assessed according to CMS.gov manual definitions. QALYs and cost per QALY were calculated using a 3% discount rate to account for residual decline to life expectancy (78.7 years). Costs per QALY were calculated for both 1 year and life expectancy, assuming no loss of benefit.
RESULT(S): A total of 360 propensity matched patients (120 open, 120 MIS, 120 robot) met inclusion. Descriptive statistics for the cohort were: age 58.8+/-13.5, 50% women, BMI 29.4+/-6.3, op time 294.4+/-119.0, LOS 4.56+/-3.31 days, EBL 515.9+/-670.0 cc, and 2.3+/-2.2 average levels fused. Rates of postop complications were significantly higher in robotic cases versus open and MIS (43% vs. 21% and 22% for open and MIS, p<0.05). However, revision rates were comparable between all groups (3% open, 3% MIS, 5% robotic, p>0.05). After factoring in complications, revisions, and purchasing and operating fees, the costs of robotic cases was significantly higher than both open and MIS surgery ($60,047.01 vs. $42,538.98 open and $41,471.21 MIS). In a sub analysis of 42 patients with BL and 1Y EQ5D data, the cost per QALY at 1Y for open, MIS, and robot assisted cases was $296,624.48, $115,911.69, and $592,734.30. If utility gained was sustained to life expectancy, the cost per QALY was $14,905.75, $5,824.71, $29,785.64 for open, MIS, and robot assisted cases.
CONCLUSION(S): Numerous advances have been made in the field of spine surgery, however, there has been limited discussion of the effect these advances have on economic outcomes. When matched for levels fused, robot assisted surgery patients had significantly higher rates of complications and 30% higher costs of surgery compared to minimally invasive and open spine surgery patients. While 1 year economic outcomes weren't optimal for robotic surgery cases, the projected costs per quality adjusted life years at life expectancy were well below established acceptable thresholds. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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In the current value-based healthcare climate where spine surgery is shifting to the ambulatory setting, factors influencing postop length of stay (LOS) are important to surgeons and hospital administrators. Pre-op patient factors including diagnosis of radiculopathy and myelopathy have yet to be investigated in this context. Operative pts ≥ 18Y with primary diagnoses of cervical myelopathy (M), radiculopathy (R), or myeloradiculopathy (MR) were included and propensity score matched by invasiveness score (Mirza et al.). Top-quartile LOS was defined as extended. M&R patients were compared using Chi² & independent t-tests. Univariate tests assessed differences in preop patient and surgical data in M&R pts and extended/non-extended LOS. Stepwise regression analysis explored factors predictive of LOS. 718 operative pts (54.5 yrs, 41.1%F, 29.1 kg/m², mean CCI 1.11) included (177 M, 383 R, and 158 MR). After PSM, 345 patients remained (115 in each diagnosis). 102 patients had E-LOS (Avg: 5.96 days), 41 M patients (mean 7.1 days), 28 R (5.9 days), and 33 MR (4.6 days). Regression showed predictors of E-LOS in R pts (R²â€¯= 0.532, p = 0.043): TS-CL, combined and posterior approach, LIV, UIV, op time, Lactated Ringer's, postoperative complications. Predictors of E-LOS in M pts (R²â€¯= 0.230, p < 0.001): age, CCI, combined and posterior approach, levels fused, UIV, EBL, neuro and any postop complications. Predictors of E-LOS in MR patients (R²â€¯= 0.152, p < 0.001): age, kyphosis, combined approach, UIV, LIV, levels fused, EBL and op time. Independent of invasiveness, patients with a primary diagnosis of myelopathy, though older aged and higher comorbidity profile, had consistently longer overall postop LOS when compared to radiculopathy or myeloradiculopathy patients.