Immediate Postoperative Change in the Upper Instrumented Screw-Vertebra Angle Is a Predictor for Proximal Junctional Kyphosis and Failure.

STUDY DESIGN: Retrospective review. OBJECTIVES: To determine if change in position of upper instrumented vertebral (UIV) screw between intraoperative prone and immediate postoperative standing radiographs is a predictor for proximal junctional kyphosis or failure (PJK/PJF). SUMMARY OF BACKGROUND DATA: Cranially directed UIV screws on post-operative radiographs have been found to be associated with PJK. Change in the screw position between intraoperative and immediate postoperative radiographs has not been studied. METHODS: Patients with posterior fusion ≥3 levels and UIV at or distal to T8, and minimum 2-year follow-up were identified from a single center database. Primary outcomes were radiographic PJK/PJF or revision for PJK/PJF. Demographic, surgical and radiographic variables, including intraoperative screw-vertebra (S-V) angle, change in S-V angle, direction of UIV screw (cranial-neutral-caudal) and rod-vertebra (R-V) angle were collected. RESULTS: 143 cases from 110 patients were included with a mean age of 62.9 years and a follow-up of 3.5 years. 54 (38%) cases developed PJK/PJF, of whom 30 required a revision. Mean S-V angle was -0.9°±5.5° intraoperative and -2.8°±5.5° postoperative. The group with PJK/PJF had a mean S-V angle change of -2.5°±2.4 while the rest had a change of -1.0°±1.6 (P=0.010). When the change in S-V angle was <5°, 33% developed PJK, this increased to 80% when it was ≥5° (P=0.001). Revision for PJK/PJF increased from 16% to 60% when S-V angle changed ≥5° (P=0.001). Regression analysis showed S-V angle change as a significant risk factor for PJK/PJF (P=0.047, OR=1.58) and for revision due to PJK/PJF (P=0.009, OR=2.21). CONCLUSIONS: Change in the S-V angle from intraop prone to immediate postop standing radiograph is a strong predictor for PJK/PJF and for revision. For each degree of S-V angle change, odds of revision for PJK/PJF increases by 2.2x. A change of 5° should alert the surgeon to the likely development of PJK/PJF requiring revision.

Comparison of No Tap (two-step) and tapping robotic assisted cortical bone trajectory screw insertion.

Workflow for cortical bone trajectory (CBT) screws includes tapping line-to-line or under tapping by 1 mm. We describe a non-tapping, two-step workflow for CBT screw placement, and compare the safety profile and time savings to the Tap (three-step) workflow. Patients undergoing robotic assisted 1-3 level posterior fusion with CBT screws for degenerative conditions were identified and separated into either a No-Tap or Tap workflow. Number of total screws, screw-related complications, estimated blood loss, operative time, robotic time, and return to the operating room were collected and analyzed. There were 91 cases (458 screws) in the No-Tap and 88 cases (466 screws) in the Tap groups, with no difference in demographics, revision status, ASA grade, approach, number of levels fused or diagnosis between cohorts. Total robotic time was lower in the No-Tap (26.7 min) versus the Tap group (30.3 min, p = 0.053). There was no difference in the number of malpositioned screws identified intraoperatively (10 vs 6, p = 0.427), screws converted to freehand (3 vs 3, p = 0.699), or screws abandoned (3 vs 2, p = 1.000). No pedicle/pars fracture or fixation failure was seen in the No-Tap cohort and one in the Tap cohort (p = 1.00). No patients in either cohort were returned to OR for malpositioned screws. This study showed that the No-Tap screw insertion workflow for robot-assisted CBT reduces robotic time without increasing complications.

The effect of myelography dye on bone density measurements utilizing Hounsfield units on CT.

OBJECTIVE: Hounsfield unit (HU) measurements of bone density on CT are increasingly used for preoperative planning in spine surgery. Postmyelogram CT is another common preoperative diagnostic study. However, there is no current literature evaluating whether HU measurements on CT are affected by the presence of myelography dye. The purpose of the current study was to determine if the presence of myelography dye affects HU measurements of bone density in CT studies. METHODS: Twenty-nine preoperative spine surgery patients who underwent both standard and postmyelography CT performed within 6 months of each other were identified. HU measurements were obtained from an elliptical region of interest using the available software on a standard PACS. Measurements were obtained on the axial cut at the midvertebral body on all lumbar vertebrae on three separate occasions and an average value was calculated for comparative analysis. A 6-week gap was used between measurements of the CT scans and the CT myelograms to diminish bias. RESULTS: The mean age of the cohort was 69 years and the average BMI was 32 kg/m2. Five patients were male and 24 were female. Six of the patients had instrumentation placed prior to the initial CT scan. The average HU measurements for CT levels L1-5 were 165, 171, 145, 154, and 225, respectively, whereas HU measurements for CT myelography of levels L1-5 were 168, 177, 148, 170, and 239, respectively. Strong correlations were noted between the HU measured on CT and CT myelography for L1 (r2 = 0.951), L2 (r2 = 0.966), L4 (r2 = 0.820), and L5 (r2 = 0.900), and moderate for L3 (r2 = 0.668). CONCLUSIONS: The presence of myelography dye had no clear effect on CT HU measurements of bone density. The results of this study support the use of CT myelograms for bone density assessment in the absence of standard CT images.

The Effect of Implant Density on Adolescent Idiopathic Scoliosis Fusion: Results of the Minimize Implants Maximize Outcomes Randomized Clinical Trial.

BACKGROUND: Severe adolescent idiopathic scoliosis (AIS) can be treated with instrumented fusion, but the number of anchors needed for optimal correction is controversial. METHODS: We conducted a multicenter, randomized study that included patients undergoing spinal fusion for single thoracic curves between 45° and 65°, the most common form of operatively treated AIS. Of the 211 patients randomized, 108 were assigned to a high-density screw pattern and 103, to a low-density screw pattern. Surgeons were instructed to use ≥1.8 implants per spinal level fused for patients in the high-implant-density group or ≤1.4 implants per spinal level fused for patients in the low-implant-density group. The primary outcome measure was the percent correction of the coronal curve at the 2-year follow-up. The power analysis for this trial required 174 patients to show equivalence, defined as a 95% confidence interval (CI) within a ±10% correction margin with a probability of 90%. RESULTS: In the intention-to-treat analysis, the mean percent correction of the coronal curve was equivalent between the high-density and low-density groups at the 2-year follow-up (67.6% versus 65.7%; difference, -1.9% [95% CI: -6.1%, 2.2%]). In the per-protocol cohorts, the mean percent correction of the coronal curve was also equivalent between the 2 groups at the 2-year follow-up (65.0% versus 66.1%; difference, 1.1% [95% CI: -3.0%, 5.2%]). A total of 6 patients in the low-density group and 5 patients in the high-density group required reoperation (p = 1.0). CONCLUSIONS: In the setting of spinal fusion for primary thoracic AIS curves between 45° and 65°, the percent coronal curve correction obtained with use of a low-implant-density construct and that obtained with use of a high-implant-density construct were equivalent. LEVEL OF EVIDENCE: Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.

Management of nonpurulent wound drainage following spinal surgery: is empiric oral antibiotic treatment appropriate?

BACKGROUND CONTEXT: Postoperative incisional concerns including nonpurulent drainage are relatively common following spine surgery. Evidence-based management protocols are lacking. PURPOSE: The purpose of this study is to determine if prescribing empiric oral antibiotics for nonpurulent wound drainage is beneficial for the prevention of chronic infection or reoperation. STUDY DESIGN: Retrospective chart review. PATIENT SAMPLE: Patients calling the office with postsurgical wound concerns. OUTCOME MEASURES: Not applicable. METHODS: In a large, multisurgeon, spine surgery practice, a review of the communications log showed that 298 patients called or messaged the office with a concern regarding postoperative nonpurulent wound drainage. Patients were prescribed empiric oral antibiotics based on surgeon preference. Patients who received empiric oral antibiotic treatment (AbxTx) were propensity matched to patients who did not (No AbxTx) based on sex, age, BMI, ASA grade, smoking status, prior spine surgery, anatomic location, and number of surgical levels. The number of patients requiring surgical intervention (debridement) and/or developing a chronic infection was determined. RESULTS: Oral antibiotics were prescribed for 112 of the 298 (38%) patients with reports of nonpurulent drainage. Demographic and surgical characteristics of the two matched cohorts were similar. Although there were more patients in the AbxTx group who required surgical intervention (n=17, 17%) compared to the No AbxTx group (n=9, 9%), this difference was not statistically significant (p=.139). The intra-operative culture results showed no growth in 94% (16/17) of the AbxTx group vs 67% (6/9) of the No AbxTx group (p=.103). One patient in each group required a return to the operating room within the year after the initial surgical debridement for management of chronic infection. CONCLUSION: In this large series (n=298) of patients with nonpurulent wound drainage following spine surgery, 87% resolved without the need for surgical intervention. Empiric oral antibiotics did not reduce the need for surgical intervention or the development of a chronic infection. In addition to the added cost, potential adverse reactions, development of resistant organisms, and inaccurate labeling of surgical site infection; empiric oral antibiotics may lead to a negative intraoperative culture for those requiring surgical intervention impacting the ability to prescribe a specific antibiotic regimen.

Comparison of revision surgery for pseudarthrosis with or without adjacent segment disease after anterior cervical discectomy and fusion.

Background: Patients with a pseudarthrosis after anterior cervical discectomy and fusion (ACDF) may have concurrent adjacent segment disease (ASD). Although prior studies have shown posterior cervical decompression and fusion (PCDF) is effective in repairing pseudarthrosis, improvement in patient reported outcomes (PROs) has been marginal. The aim of this study is to evaluate the effectiveness of PCDF in achieving symptom relief in patients with pseudarthrosis after ACDF and whether that is altered by the additional treatment of ASD. Methods: Thirty-two patients with pseudarthrosis were compared with 31 patients with pseudarthrosis and concurrent ASD after ACDF who underwent revision PCDF with a minimum 1-year follow-up. Primary outcomes measures included the neck disability index (NDI), and numerical rating scale (NRS) scores for neck and arm pain. Secondary measures included estimated blood loss (EBL), operating room (OR) time, and length of stay. Results: Demographics between cohorts were similar, however there was a significantly higher mean body mass index (BMI) in the group with concurrent ASD (32.23 vs. 27.76, p=.007). Patients with concurrent ASD had more levels fused during PCDF (3.7 vs. 1.9, p<.001), greater EBL (165 cc vs. 106 cc, p=.054), and longer OR time (256 minutes vs. 202 minutes, p<.000). Preoperative PROs for NDI (56.7 vs. 56.5, p=.954), NRS arm pain (5.9 vs. 5.7, p=.758), and NRS neck pain (6.6 vs. 6.8, p=.726) were similar in both cohorts. At 12 months patients with concurrent ASD experienced a slightly greater, but not statistically significant, improvement in PROs (Δ NDI 4.40 vs. -1.44, Δ NRS neck pain 1.17 vs. 0.42, Δ NRS arm pain 1.28 vs. 0.10, p=.107). Conclusions: PCDF is a standard procedure for treatment of pseudarthrosis following ACDF, however improvements in PROs are marginal. Slightly greater improvements were seen in patients whose indication for surgery also included concurrent ASD, rather than a diagnosis of pseudarthrosis alone.

Correlation between bone density measurements on CT or MRI versus DEXA scan: A systematic review.

Background: Novel methods of bone density assessment using computed tomography (CT) and magnetic resonance imaging (MRI) have been increasingly reported in the spine surgery literature. Correlations between these newer measurements and traditional Dual-Energy X-ray Absorptiometry (DEXA) is not well known. The purpose of this study is to perform an updated systematic review of correlations between bone mineral density (BMD) from CT or MRI and DEXA. Methods: Articles published between 2011 and 2021 that reported correlations between the CT-HU or MRI measurements to DEXA t-scores or BMD of lumbar spine or hip were included in this systematic review. Results: A total of 25 studies (15 CT, 10 MRI) met the inclusion criteria with a total number of 2,745 patients. The pooled correlation coefficient of spine CT-HU versus spine DEXA, spine CT-HU versus hip DEXA and spine CT-HU versus lowest t-score were 0.60, 0.50 and 0.60 respectively. Regarding spine DEXA parameters, the pooled r2 for spine CT-HU versus spine t-score was 0.684 and spine CT-HU versus spine BMD was 0.598. Furthermore, in patients undergoing spine surgery in four studies, the pooled correlation between spine CT and spine DEXA was (r2: 0.64). In MRI studies, the pooled r2 of spine MRI versus spine DEXA and spine MRI versus hip DEXA were -0.41 and -0.44 respectively. Conclusions: CT-HU has stronger correlations with DEXA than MRI measurements. Lumbar CT-HU has the highest pooled correlation (r2 = 0.6) with both spine DEXA and lowest skeletal t-score followed by lumbar CT-HU with hip DEXA (r2 = 0.5) and lumbar MRI with hip (r2 = 0.44) and spine (r2 = 0.41) DEXA. Both imaging modalities achieved only a moderate correlation with DEXA. Few studies in both modalities have investigated the correlation in spine surgery populations and the available data shows that the correlations are worse in the degenerative spine population. A careful interruption of CT HU and MRI measurement when evaluation of BMD as they only moderately correlated with DEXA scores. At this time, it is unclear which modality is a better predictor of mechanical complications and clinical outcomes in spine surgery patients.

Early Experience With an Endocrinology Preoperative Fast-Track Program for Optimizing Spine Surgery Candidates With Poorly Controlled Diabetes Mellitus.

INTRODUCTION: Previous studies demonstrated an increase in adverse outcomes for patients undergoing elective surgeries with poorly controlled diabetes mellitus. At a large, tertiary-care spine center with a notable population of patients with poorly controlled diabetes, an Endocrinology Fast-Track (EFT) program was developed to improve patient optimization before elective spine surgery. The purpose of this study was to report our early experience. METHODS: Seventy-five patients who were scheduled for elective spine surgery were noted to have Hgb A1c > 7 on preoperative evaluation. Thirty-two patients accepted referral to the EFT program and 43 declined (non-EFT). Mean preoperative Hgb A1c was similar between groups (EFT: 8.79 versus non-EFT: 9.26, P = 0.221). The Fast-Track program included counseling, education, and medical management. RESULTS: Patients in the two groups were similar in number of females (EFT: 17 versus non-EFT: 17, P = 0.348), age (EFT: 57.7 versus non-EFT: 60.6, P = 0.280), and body mass index (EFT: 34.6 versus non-EFT: 33.0, P = 0.341). A smaller number of smokers were there in the EFT group (1) compared with the non-EFT group (15, P = 0.003). The proportion of patients on insulin (EFT: 19 versus non-EFT: 23, P = 0.814) and oral hypoglycemics (EFT: 29 versus non-EFT: 39, P = 0.983) was similar between the two groups. Surgical clearance for patients with a documented preoperative Hgb A1c of < 7 or equivalent fructosamine level was significantly better in the Fast-Track group compared with the non-Fast-Track group (91% versus 42%, P = 0.000). Although most patients who declined the Fast-Track program did not obtain clearance for surgery, mean Hgb A1c was improved at the latest follow-up in both groups for those who obtained surgical clearance (7.10 versus 6.78, P = 0.470). DISCUSSION: A novel EFT program was successful in obtaining acceptable blood glucose control in patients recommended for spine surgery who had poorly controlled diabetes mellitus on preoperative evaluation. The improved blood glucose control was maintained at the latest follow-up.

Correction and Maintenance of Cervical Alignment: 3-Level ACDF Versus Corpectomy-ACDF "Hybrid" Procedures.

STUDY DESIGN: Longitudinal observational comparative cohorts. OBJECTIVE: The objective of this study is to compare 3 and 12-month radiographic sagittal parameters and patient-reported outcomes (PROs) in patients who underwent 3-level ACDF or a hybrid procedure. SUMMARY OF BACKGROUND DATA: Anterior Cervical Discectomy and Fusion (ACDF), Anterior Cervical Corpectomy and Fusion (ACCF), and hybrids (combination ACCF-ACDF) are common procedures used to treat symptomatic cervical spondylosis. Although there is a relative abundance of literature comparing 1-level ACCF versus 2-level ACDF and 2-level ACCF versus 3-level ACDF, detailed comparisons of 3-level ACDF versus hybrid procedures have not been extensively addressed. METHODS: Patients who underwent a 3-Level ACDF (3L-ACDF, N=47) or 1-Level Corpectomy/1-Level ACDF (Hybrid, N=52) with at least a 12-month post-op data available were identified. Standard demographic, surgical and PROs were collected in addition to preoperative and postoperative radiographic data, including C2 plumb line (C2PL), C2-C7 lordosis (CL), segmental lordosis (SL), and T1 slope (T1S). RESULTS: The 2 cohorts were similar in terms of demographics. At 3 months post-op, CL (9.04° vs. -2.12°, P =0.00) and SL (6.06° vs. -2.26°, P =0.003) were significantly greater in the 3L-ACDF group versus the HYBRID group. This significant difference was maintained at 12 months postoperative for CL [(6.62° vs. -0.60°, P =0.015) but not for SL (2.36° vs. -1.09°, P =0.199)]. There were no differences in PROs between the 2 groups before surgery, at 3 months postoperative or 12 months postoperative. Seven patients required revision surgery in the 1-year study period (1 in the 3L-ACDF, and 6 in the Hybrid P <0.001). CONCLUSIONS: Three level ACDF resulted in greater C2-C7 lordosis and segmental lordosis postoperatively, which was maintained at 1 year for cervical lordosis. While PROs were similar between the groups, patients with hybrid instrumentation required significantly more revision surgeries than those treated with 3-level ACDF.

Cost-Effectiveness of Intraoperative Electromyography to Determine Adequate Screw Position.

STUDY DESIGN: Prospective observational cohort. OBJECTIVES: To examine the cost-effectiveness of IntraOperative ElectroMyeloGraphy (IO-EMG) by evaluating how often an abnormal IO-EMG signal changed the surgeon's surgical plan, or replaced a pedicle screw either intra-operatively or as a second unplanned surgery. METHODS: Patients undergoing instrumented posterolateral lumbar fusion were monitored with intraoperative triggered EMG's. Pedicle screws were placed freehand from L1 to S1 by attending physicians and fellows. Concern for pedicle breach was a screw stimulation<10 mA. RESULTS: There were 145 cases with a total of 725 pedicle screws placed. Mean age was 57.8 ± 14.2 yrs, OR time was 238 ± 95 minutes, EBL was 426.8 ± 354.3cc. Mean number of surgical levels fused was 2.7 ± 1.1. 686 (95%) screws stimulated at >10 mA and 39 (5%) screws stimulated at <10 mA. All 39 screws were removed and pedicles re-examined. Intraoperative screw repositioning was necessary in 8 of 145 cases (6%). No patient required a return to the OR for screw repositioning. As a worst case cost analysis, assuming the 8 patients requiring intraoperative screw positioning would have returned to the OR at a cost of $11,798 per readmission, the per patient cost is $651 which is less than the ION per patient cost of $750. CONCLUSIONS: Only 1% of the 725 lumbar pedicle screws placed in 8 of 145 cases required repositioning. Due to the infrequency of pedicle wall breaches and the cost of ION, the utility of this modality in straightforward lumbar fusions should be critically evaluated.

Predictors of segmental lumbar lordosis following midline posterior (transforaminal) lumbar interbody fusion: Does interbody device type matter?

Background: Controversy exists regarding the ability of posterior (transforaminal) lumbar interbody fusion (PLIF/TLIF) to achieve lordosis. We hypothesized that an interbody device (IBD) designed for positioning in the anterior disc space produces greater lordosis than IBDs designed for straight-in positioning. The purpose of this study is to determine if using either an anterior-position or straight-in position IBD design were associated with successful achievement of postoperative lordosis. Methods: A consecutive series of patients undergoing a undergoing a single-level, posterior open midline (transforaminal) lumbar interbody fusion procedure for degenerative spine conditions during a time period when the two types of interbody devices were being used at surgeon discretion were identified from a multi-surgeon academic training center. Patient demographics and radiographic measures including surgical level lordosis (SLL), anterior disc height, middle disc height, posterior disc height, IBD height, and IBD insertion depth were measured on preop, immediate postop, and one-year postop standing radiographs using PACS. Group comparison and regression analysis were performed using SPSS. Results: Sixty-one patients were included (n=37 anterior, n=34 straight-in). Mean age was 59.8±8.7 years, 32 (52%) were female. There was no difference between IBD type (anterior vs. straight-in) for mean Pre-op SLL (19±7° vs. 20±6°, p=0.7), Post-op SLL (21±5° vs 21±6°, p=0.5), or Change in SLL (2±4° vs. 1±5°, p=0.2). Regression analysis showed that Pre-op SLL was the only variable associated with Change in SLL (Beta = negative 0.48, p=0.000). While the mean Change in SLL could be considered clinically insignificant, there was wide variability: from a loss of 9° to a gain of 13°. Gain of lordosis >5° only occurred when Pre-op SLL was <21°, and loss of lordosis >5° only occurred when Pre-op SLL was >21°. Conclusions: While group averages showed an insignificant change in segmental lordosis following a posterior (transforaminal) interbody fusion regardless of interbody device type, pre-operative lordosis was correlated with a clinically significant change in segmental lordosis. Preoperative hypolordotic discs were more likely to gain significant lordosis, while preoperative hyperlordotic discs were more likely to lose significant lordosis. Surgeon awareness of this tendency can help guide surgical planning and technique.

Severity and Outcome of Neurologic Deficits in Patients with Pyogenic Spondylodiscitis: A Systematic Review.

Patients with advanced pyogenic spondylodiscitis can present with neurologic deficits. However, the prevalence, severity, and outcome of the neurologic deficits are not well known. A systematic review was performed to improve the knowledge of this commonly encountered clinical scenario. The considerable number of severe neurologic deficits in addition to their poor recovery, even after surgical intervention, demonstrates that the early diagnosis of pyogenic spondylodiscitis is crucial. Prompt surgical intervention is likely associated with a greater chance of improvement of neurologic status than nonsurgical treatment.

Changes in Recombinant Human Bone Morphogenetic Protein-2 Use in Posterior Fusion Over the Past Two Decades.

Background In 2011, studies suggested that complications and cancer rates associated with bone morphogenetic protein (BMP) were greater than previously reported. However, later studies reported complication rates similar to prior literature and no increased cancer rate. We evaluated the pattern of clinical utilization of BMP in posteriorly based lumbar fusion by comparing two periods: 2002-2004 and 2017-2019. Methods Patients who received BMP from 2002-2004 (Early) and 2017-2019 (Late) from a single multi-surgeon institution who had a lumbar fusion were identified. One hundred patients from each cohort were randomly selected. Mean total BMP used at each level and the proportion of BMP placed in the interbody space versus posterolateral gutters were evaluated. Results In the transforaminal lumbar intebody fusion (TLIF) cohort, the total BMP dose in the Late group (6.15 mg) was nearly half of that used in the Early group (12.04 mg, p<0.000). The amount of BMP used in the posterolateral gutters remained similar (Early: 4.01 mg vs Late: 3.38 mg, p=0.222). The amount of BMP used in the interbody space was less in the Late group (2.76 mg) compared to the Early group (8.03 mg, p<0.000). In the posterior spinal fusion (PSF) cohort, the total BMP dose remained similar between the Early (11.96 mg) and the Late groups (10.82 mg, p=0.007). Conclusion Change in the use of BMP in TLIF cases was driven by the complications reported in the literature with no change in outcome. A similar impetus was not seen for PSF.

Operative versus nonoperative treatment for adult symptomatic lumbar scoliosis at 5-year follow-up: durability of outcomes and impact of treatment-related serious adverse events.

OBJECTIVE: Although short-term adult symptomatic lumbar scoliosis (ASLS) studies favor operative over nonoperative treatment, longer outcomes are critical for assessment of treatment durability, especially for operative treatment, because the majority of implant failures and nonunions present between 2 and 5 years after surgery. The objectives of this study were to assess the durability of treatment outcomes for operative versus nonoperative treatment of ASLS, to report the rates and types of associated serious adverse events (SAEs), and to determine the potential impact of treatment-related SAEs on outcomes. METHODS: The ASLS-1 (Adult Symptomatic Lumbar Scoliosis-1) trial is an NIH-sponsored multicenter prospective study to assess operative versus nonoperative ASLS treatment. Patients were 40-80 years of age and had ASLS (Cobb angle ≥ 30° and Oswestry Disability Index [ODI] ≥ 20 or Scoliosis Research Society [SRS]-22 subscore ≤ 4.0 in the Pain, Function, and/or Self-Image domains). Patients receiving operative and nonoperative treatment were compared using as-treated analysis, and the impact of related SAEs was assessed. Primary outcome measures were ODI and SRS-22. RESULTS: The 286 patients with ASLS (107 with nonoperative treatment, 179 with operative treatment) had 2-year and 5-year follow-up rates of 90% (n = 256) and 74% (n = 211), respectively. At 5 years, compared with patients treated nonoperatively, those who underwent surgery had greater improvement in ODI (mean difference -15.2 [95% CI -18.7 to -11.7]) and SRS-22 subscore (mean difference 0.63 [95% CI 0.48-0.78]) (p < 0.001), with treatment effects (TEs) exceeding the minimum detectable measurement difference (MDMD) for ODI (7) and SRS-22 subscore (0.4). TEs at 5 years remained as favorable as 2-year TEs (ODI -13.9, SRS-22 0.52). For patients in the operative group, the incidence rates of treatment-related SAEs during the first 2 years and 2-5 years after surgery were 22.38 and 8.17 per 100 person-years, respectively. At 5 years, patients in the operative group who had 1 treatment-related SAE still had significantly greater improvement, with TEs (ODI -12.2, SRS-22 0.53; p < 0.001) exceeding the MDMD. Twelve patients who received surgery and who had 2 or more treatment-related SAEs had greater improvement than nonsurgically treated patients based on ODI (TE -8.34, p = 0.017) and SRS-22 (TE 0.32, p = 0.029), but the SRS-22 TE did not exceed the MDMD. CONCLUSIONS: The significantly greater improvement of operative versus nonoperative treatment for ASLS at 2 years was durably maintained at the 5-year follow-up. Patients in the operative cohort with a treatment-related SAE still had greater improvement than patients in the nonoperative cohort. These findings have important implications for patient counseling and future cost-effectiveness assessments.

Drivers of in-hospital opioid consumption in patients undergoing lumbar fusion surgery.

BACKGROUND: With the current opioid crisis, as many as 38% of patients are still on opioids one year after elective spine surgery. Identifying drivers of in-hospital opioid consumption may decrease subsequent opioid dependence. We aimed to identify the drivers of in-hospital opioid consumption in patients undergoing 1-2-level instrumented lumbar fusions. METHODS: This is a retrospective cohort study. Electronic medical record analysts identified consecutive patients undergoing 1-2 level instrumented lumbar fusions for degenerative lumbar conditions from 2016 to 2018 from a single-center hospital administrative database. Oral, intravenous, and transdermal opioid dose administrations were converted to morphine milligram equivalents (MME). Linear regression analysis was used to determine associations between postoperative day (POD) 4 cumulative in-hospital MMEs and the patients' baseline characteristics including body mass index (BMI), race, American Society of Anesthesiologists (ASA) grade, smoking status, marital status, insurance type, zip code, number of fused levels, approach and preoperative opioid use. RESULTS: A total of 1,502 patients were included. The mean cumulative MMEs at POD 4 was 251.5. Linear regression analysis yielded four drivers including younger age, preoperative opioid use, current smokers and more levels fused. There were no associations with surgical approach, zip code, ASA grade, marital status, BMI, race or insurance type. CONCLUSIONS: Use of preoperative opioids and smoking are modifiable risk factors for higher in-hospital opioid consumption and can be targets for intervention prior to surgery in order to decrease in-hospital opioid use.

Health-related quality-of-life improvement with lumbar fusion in patients with lower-extremity arthritis.

OBJECTIVE: Lumbar fusion can lead to significant improvements in patient-reported outcomes (PROs) in patients with degenerative conditions. It is unknown whether the presence of hip or knee arthritis confounds the responses of patients to low-back-specific PROs. This study examined PROs with lumbar fusion in patients with concomitant lower-extremity arthritis. The purpose of the current study was to examine whether patients with significant lower-extremity arthritis who undergo lumbar fusion achieve similar improvements in low-back-specific PROs compared to patients without lower-extremity arthritis. METHODS: Patients were identified from a prospectively enrolled multicenter registry of patients undergoing lumbar fusion surgery for degenerative conditions. Two hundred thirty patients identified with lumbar fusion and who also had concomitant lower-extremity arthritis were propensity matched to 233 patients who did not have lower-extremity arthritis based on age, BMI, sex, smoking status, American Society of Anesthesiologists grade, number of levels fused, and surgical approach. One-year improvement in PROs, numeric rating scales (0-10) for back and leg pain, and the Oswestry Disability Index and EuroQol-5D scores were compared for patients with and without lower-extremity arthritis. RESULTS: Baseline demographics and preoperative outcome measures did not differ between the two propensity-matched groups with 110 cases each. Patients with concomitant lower-extremity arthritis achieved similar improvement in health-related quality-of-life measures to patients without lower-extremity arthritis, with no significant differences between the groups (p > 0.10). CONCLUSIONS: The presence of lower-extremity arthritis does not adversely affect the results of lumbar fusion in properly selected patients. Patients with lower-extremity arthritis who undergo lumbar fusion can achieve meaningful improvement in PROs similar to patients without arthritis.

Drivers for nonhome discharge in a consecutive series of 1502 patients undergoing 1- or 2-level lumbar fusion.

OBJECTIVE: Unexpected nonhome discharge causes additional costs in the current reimbursement models, especially to the payor. Nonhome discharge is also related to longer length of hospital stay and therefore higher healthcare costs to society. With increasing demand for spine surgery, it is important to minimize costs by streamlining discharges and reducing length of hospital stay. Identifying factors associated with nonhome discharge can be useful for early intervention for discharge planning. The authors aimed to identify the drivers of nonhome discharge in patients undergoing 1- or 2-level instrumented lumbar fusion. METHODS: The electronic medical records from a single-center hospital administrative database were analyzed for consecutive patients who underwent 1- to 2-level instrumented lumbar fusion for degenerative lumbar conditions during the period from 2016 to 2018. Discharge disposition was determined as home or nonhome. A logistic regression analysis was used to determine associations between nonhome discharge and age, sex, body mass index (BMI), race, American Society of Anesthesiologists grade, smoking status, marital status, insurance type, residence in an underserved zip code, and operative factors. RESULTS: A total of 1502 patients were included. The majority (81%) were discharged home. Factors associated with a nonhome discharge were older age, higher BMI, living in an underserved zip code, not being married, being on government insurance, and having more levels fused. Patients discharged to a nonhome facility had longer lengths of hospital stay (5.6 vs 3.0 days, p < 0.001) and significantly increased hospital costs ($21,204 vs $17,518, p < 0.001). CONCLUSIONS: Increased age, greater BMI, residence in an underserved zip code, not being married, and government insurance are drivers for discharge to a nonhome facility after a 1- to 2-level instrumented lumbar fusion. Early identification and intervention for these patients, even before admission, may decrease the length of hospital stay and medical costs.

Cost-effectiveness of adult lumbar scoliosis surgery: an as-treated analysis from the adult symptomatic scoliosis surgery trial with 5-year follow-up.

STUDY DESIGN: Longitudinal comparative cohort. OBJECTIVE: The purpose of this study is to report on the cost-effectiveness of surgical versus non-surgical treatment for Adult Symptomatic Lumbar Scoliosis (ASLS) using the as-treated data and provide a comparison to previously reported intent-to-treat (ITT) analysis. Adult spinal deformity is a relatively prevalent condition for which surgical treatment has become increasingly common but concerns surrounding complications, revision rates and cost-effectiveness remain unresolved. Of these issues, cost-effectiveness is perhaps the most difficult to quantify as the requisite data is difficult to obtain. The purpose of this study is to report on the cost-effectiveness of surgical versus non-surgical treatment for ASLS using the as-treated data and provide a comparison to previously reported ITT analysis. METHODS: Patients with at least 5-year follow-up data within the same treatment arm were included. Data collected every 3 months included use of nonoperative modalities, medications and employment status. Costs for surgeries and non-operative modalities were determined using Medicare Allowable rates. Medication costs were determined using the RedBook and indirect costs were calculated based on the reported employment status and income. Quality-Adjusted Life Years (QALY) was determined using the SF-6D. RESULTS: Of 226 patients, 195 patients (73 Non-op, 122 Op) met inclusion criteria. At 5 years, 29 (24%) patients in the Op group had a revision surgery of whom two had two revisions and one had three revisions. The cumulative cost for the Op group was $111,451 with a cumulative QALY gain of 2.3. The cumulative cost for the Non-Op group was $29,124 with a cumulative QALY gain of 0.4. This results in an ICER of $44,033 in favor of Op treatment. CONCLUSION: This as-treated cost-effectiveness analysis demonstrates that surgical treatment for adult lumbar scoliosis becomes favorable at year-three, 1 year earlier than suggested by a previous intent-to-treat analysis. LEVEL OF EVIDENCE: II.

Asymptomatic ACDF Nonunions Underestimate the True Prevalence of Radiographic Pseudarthrosis.

STUDY DESIGN: Secondary analysis of subjects in the control anterior cervical discectomy and fusion (ACDF) arm of Medtronic Investigational Device Exemption (IDE) trials for cervical disc arthroplasty (CDA). OBJECTIVES: To compare patient-reported outcomes (PROs) in patients with radiographic nonunion to patients with a solid fusion. SUMMARY OF BACKGROUND DATA: The true prevalence of nonunion after ACDF is unknown. Nonunion may be under-reported, as some patients are not symptomatic enough to justify radiographic evaluation. METHODS: Three hundred forty-five subjects enrolled in the control arm of IDE trials for CDA who had single-level ACDF with allograft and plate with 24 month data formed the study cohort. Using the 24-month postop evaluation, subjects were divided into those who had radiographic fusion and those who did not using strict study criteria. SF-36, NDI, Neck and Arm pain NRS scores were reported at 12, 24, 36, 60, and 84 months postop. For subjects who had secondary surgery failures, the last observations before the secondary surgery were carried forward to future visits for the analysis. RESULTS: Forty-four (13%) patients had radiographic nonunion and 301 (87%) were fused at 24 months postop. At 24 months, PROs were similar between the two groups. Seven patients in the Nonunion group (16%) and 10 (3%) in the Fused group had additional surgery at the index level prior to the 24 follow-up (P = 0.003). Over the 84-month follow-up a total of 9 patients in the Nonunion group (21%) and 22 (7%) in the Fused group had additional surgery at the index level (P = 0.009). CONCLUSION: While the radiographic nonunion rate at 24 months was 13%, PROs show that many of the radiographic nonunions were asymptomatic. Although the majority of patients with radiographic nonunion did not undergo additional surgery, the rate of secondary surgeries at the index level was significantly higher in the radiographic nonunion group. LEVEL OF EVIDENCE: 2.