The impact of rheumatoid arthritis and immunotherapy on outcomes following cervical fusion.

Study DesignRetrospective Cohort Study.ObjectivesCervical disc arthroplasty (CDA) and anterior cervical discectomy and fusion (ACDF) are both safe and effective surgical options for cervical spine pathologies such as myelopathy and radiculopathy. Comparative outcomes data for CDA versus ACDF in osteoporotic female patients remain limited despite this population's increased vulnerability to postoperative complications. This study compares postoperative outcomes and healthcare utilization between single-level ACDF and CDA in this patient group.MethodsAdult female patients aged ≥55years with osteoporosis who underwent single-level CDA or ACDF between 2010 and 2022 were identified using the PearlDiver national database. A one-year washout period for prior cervical surgeries was applied, and patients receiving both procedures simultaneously were excluded. Eligible patients were matched three-to-one on age, Elixhauser Comorbidity Index (ECI), and smoking history. Outcomes included 90-day medical and surgical complications and 30-day, 90-day, and 2-year healthcare utilization metrics. Welch's t-tests and Pearson χ2 tests were used for all comparisons. Statistical significance was set at p < .05.Results678 female patients with osteoporosis underwent CDA (n = 170) or ACDF (n = 508). No baseline comorbidities differed significantly between groups. Incidences of 90-day medical and surgical complications and all healthcare utilization metrics were comparable between groups.ConclusionsOur findings suggest CDA can be performed safely in female patients with an administrative diagnosis of osteoporosis, warranting further investigation with stratified bone-density-specific analyses.

Retrospective cohort study. To understand how preoperative LDL levels, statin intake, and fish oil intake affect rates of pseudarthrosis after single-level and multilevel ACDF. Anterior cervical discectomy and fusion (ACDF) is commonly performed to treat cervical degenerative diseases or injuries causing neck pain, myelopathy, and radiculopathy. Pseudarthrosis following ACDF can lead to persistent symptoms and may require revision surgery. No studies have explored the link between low-density lipoprotein (LDL) levels and statin or fish oil intake on pseudarthrosis in ACDF. Patients undergoing ACDF were identified using TriNetX, a health care database with over 100 million patients. Pseudarthrosis rates following single-level and multilevel ACDF were compared between patients with high versus low LDL within one year before surgery. Pseudarthrosis rates were also compared between patients taking or not taking a statin as well as patients taking or not taking fish oil within six months before surgery. For all analyses, patients underwent propensity score matching in a 1:1 ratio based on relevant demographic factors and comorbidities. Patients with an LDL above 142mg/dL, compared with below 66mg/dL, had significantly higher rates of pseudarthrosis at six months, one year, and two years after single-level and multilevel ACDF. Patients not taking a statin or fish oil, compared with those taking a statin or fish oil, respectively, also had significantly higher rates of pseudarthrosis at all time points after multilevel ACDF, but not single-level ACDF. Low LDL levels are associated with reduced rates of pseudarthrosis after single-level and multilevel ACDF. Statin and fish oil intake before surgery are also associated with reduced rates of pseudarthrosis after multilevel, but not single-level ACDF. These associations may be used for preoperative planning, patient optimization, and risk stratification.

Cervical Disc Arthroplasty Is Safe Across Various Obesity Levels

Retrospective database study. To compare outcomes between 1-, 2-, 3-, and 4- level anterior cervical discectomy and fusions (ACDF) and posterior cervical fusions (PCF) procedures using a national database. Surgical outcomes involving 3- or 4-level ACDF and PCF cases are not well-described. As there are situations where both ACDF and PCF can be employed, it is important to compare the risks and benefits of both procedures. Patients who underwent ACDF or PCF between 2010 and 2020 were identified in PearlDiver using current procedural terminology codes. Surgeries done for infectious, traumatic, or neoplastic etiologies were excluded. 2-year reoperations and 90-day readmissions were queried. Surgical complications and transfusions were compiled using ICD-9/10 billing codes. ACDF and PCF procedures were then matched by age, sex, Charlson Comorbidity Index, and a number of levels fused, and the above outcomes were compared. In all, 31,301 PCFs and 110,526 ACDFs were identified. After matching for age, sex, and Charlson Comorbidity Index, a total of 30,353 ACDF and PCF procedures were compared. Three-level and 4-level PCFs had higher rates of 90-day postoperative surgical complications compared with ACDF (OR=2.4 and 2.87, respectively; P <0.001). In addition, higher rates of 90-day readmissions were noted in 3-level PCF compared with 3-level ACDF (OR=1.24, P <0.001). Ninety-day postoperative transfusions were higher in both 3- and 4-level PCFs (OR=2.44 and 18.27, respectively; P <0.001). Two-year reoperations rates were higher for 3-level PCF procedures than 3-level ACDF (OR=1.22; P =0.01). Patients who underwent 3-4-level ACDF had lower rates of readmission, blood transfusions, and postoperative complications compared with 3-4-level PCF. This data suggests that in cases of 3-4-level pathology with clinical equipoise regarding approach, ACDF may be associated with less short-term morbidity, however, data on fusion rates and adjacent level disease are needed.

A retrospective case-control study. This study aimed to compare rates and risk factors for all-cause 5-year revisions for patients undergoing primary single-level cervical disc arthroplasty (CDA) versus anterior cervical discectomy and fusion (ACDF). Prospective studies have compared patient-reported outcomes, adjacent segment degeneration, and long-term revisions between CDA and ACDF. Despite these high-level evidence studies, well-powered, large investigations have not been adequately reported. A nationwide database was queried for patients undergoing primary single-level CDA or ACDF for degenerative cervical spine pathology. Further inclusion criteria consisted of patients having a minimum 5-year follow-up. Patients undergoing CDA were in a 1:5 ratio matched to patients undergoing ACDF by age, sex, comorbidities, and overall Elixhauser comorbidity index (ECI). Objectives were to compare the rates and risk factors of all-cause 5-year revisions for those undergoing single-level CDA versus ACDF. Multivariate logistic regression models computed the odds ratios (ORs) of revisions within 5 years. P values of less than 0.001 were significant. A total of 32,953 patients underwent single-level CDA (N=5,640) or ACDF (N=27,313) with a 5-year minimum follow-up. The incidence of all-cause revisions within 5 years was 1.24% for CDA and 9.23% for ACDF ( P <0.001). After adjustment, patients undergoing single-level ACDF had significantly higher odds of all-cause revisions within 5 years (OR: 8.09; P <0.0001). Additional patient-specific factors associated with revisions were a history of reported drug abuse (OR: 1.51; P <0.0001), depression (OR: 1.23; P <0.0001), cardiac arrhythmias (OR: 1.21; P =0.0008), hypertension (OR: 1.20; P =0.0006), and tobacco use (OR: 1.18; P =0.0003). In this study of nearly 33,000 single-level cervical spine surgeries with minimum 5-year follow-up, all-cause revision rates were significantly lower for patients undergoing CDA. Surgeons may use this data to counsel patients regarding 5-year revisions following single-level CDA or ACDF. III.

Prospective randomized controlled trial. This trial was designed to understand safety and effectiveness outcomes in subjects with three-level cervical degenerative disc disease treated with anterior cervical discectomy and fusion (ACDF) alone or supplemented with a posterior cervical fusion (PCF) performed using an investigational posterior cervical stabilization system (PCSS). ACDF remains the most common surgical treatment for cervical disc disease. Long-segment (3+ disc levels) procedures are associated with increased risk of complications including symptomatic nonunion. Supplementing ACDF with PCF to form a circumferential cervical fusion (CCF) improves biomechanical stability but increases the surgical burden for the patient. This multicenter study compared outcomes in participants with three-level symptomatic cervical disc degeneration treated with either ACDF or CCF. The CCF procedure incorporated PCF with PCSS. The primary endpoint was 12-month fusion success, defined by bridging bone across the interbody and range of motion <2° across all treated disc levels. The 24-month secondary endpoint was a composite of fusion success, neck disability index (NDI) improvement, neurological status success, and freedom from surgical revision. This protocol-defined interim analysis included 202 participants with 12-month outcomes and 116 participants with 24-month outcomes. Twelve-month fusion success was higher for CCF (61/100, 61%) compared with ACDF (17/102, 17%) ( P <0.001). The 24-month secondary endpoint was also improved with CCF compared with ACDF [51% (30/59) vs. 23% (13/57); P =0.002]. Revision rates were lower for CCF (1/59, 2%) compared with ACDF (13/57, 23%) ( P <0.001), with 11 of 13 ACDF revisions addressing symptomatic nonunion. Adding supplemental PCF with PCSS did not increase the rates of adverse events (ACDF=65%, CCF=46%, P =0.005). This study represents the first randomized controlled trial assessing treatment of three-level cervical disc disease. Long-segment ACDF demonstrated low fusion rates and high rates of revision. Adding supplemental PCF with PCSS improved fusion without increasing the risk of surgical complications.

Background: Cervical spine fusion surgeries, including anterior cervical discectomy and fusion (ACDF) and posterior cervical decompression and fusion (PCDF), are indicated to address cervical spine diseases. Proton pump inhibitors (PPIs), widely used for acid-related disorders, may influence bone metabolism and potentially affect surgical outcomes. This study investigates the association between preoperative PPI use and complications after cervical spine fusion. Methods: Using the TriNetX database, we performed a retrospective analysis comparing outcomes in patients undergoing cervical spine fusion with or without PPI use. Cohorts were identified based on PPI use within 90 days before surgery and matched using propensity scores to balance demographic and other potentially confounding clinical factors. Outcomes were evaluated over a 90-day postoperative period for ACDF, PCDF, and combined procedures. Results: Within 90 days postoperatively, preoperative PPI use was associated with significantly increased risks of several complications. In ACDF only, PPI use increased the risk of myocardial infarction (MI) (RR: 1.464, P =0.036), acute kidney injury (AKI) (RR: 1.367, P =0.006), sepsis (RR: 1.341, P =0.02), wound disruption (RR: 1.525, P =0.01), and infection (RR: 1.319, P =0.008). In PCDF only, PPI use increased the risk of sepsis (RR: 1.305, P =0.004). Combined cervical fusion procedures led to higher risks of stroke (RR: 1.233, P =0.033), MI (RR: 1.303, P =0.018), sepsis (RR: 1.238, P =0.001), AKI (RR: 1.326, P &lt;0.001), infection (RR: 1.220, P &lt;0.001), and wound disruption (RR: 1.260, P &lt;0.001) in patients with PPI use compared with non-users. Conclusions: These findings suggest that PPI use may be associated with increased risk of complications after cervical spine fusion. Further research is needed to understand the mechanisms of this association and guide management strategies for PPI use in these patients.

No scientific evidence on restrictions for patients following an anterior cervical discectomy and fusion (ACDF) is available. The goal of this study is to assess the practice and patterns of restrictions after single-level and multilevel ACDF at an academic institution. We submitted two questionnaires, for restrictions after single-level and multilevel ACDF, to 18 spine surgeons at our institution. Questions included length of time in practice, use of cervical collar, postoperative restrictions and practices. We received 10 complete responses. Four (40%) of the respondents were in practice for less than 5 years; 3 (30%) 5 or more years, but less than 10; 1 (10%) 10 or more years, but less than 20; 2 (20%) 20 or more years. Only two (20%) surgeons recommend a cervical collar after a single-level ACDF, while seven (70%) do so after a multilevel ACDF, for an average of 9.1 weeks and standard deviation (SD) of 2.8. Nine surgeons (90%) reported providing lifting restrictions after a single-level and multilevel ACDF, with a mean of 10 kg and SD of 2.5 in both cases. 5 (50%) give driving restrictions after a single-level ACDF, eight (80%) do so after a multilevel. eight (80%) recommend physical therapy after both single-level and multilevel ACDF. three (30%) obtain a CT to confirm fusion at one year. Only two (20%) recommend a bone stimulator. Significant variability exists among surgeons in regards to restrictions following ACDF, but some areas of consensus emerged: 90% of respondents give lifting restrictions, with a mean of 10 kg, 80% recommend physical therapy for a range of motion and muscle strengthening.

Retrospective cohort study. To compare elective single-level anterior cervical discectomy and fusion (ACDF) versus posterior cervical decompression and fusion (PCDF) for degenerative cervical myelopathy (DCM) in terms of (1) cost, (2) length of hospital stay, and (3) discharge destination in Medicare patients. A sub-analysis of potential cost drivers was also performed. In the era of value-based medicine, there is substantial interest in reducing the cost of care. Both ACDF and PCDF are used to treat DCM but carry different morbidity and risk profiles that can impact hospital resource utilization. However, this has not been assessed on a national level. Patients undergoing single-level elective ACDF and PCDF surgery were identified using the 2019 Medicare Provider Analysis and Review (MedPAR) Limited Data Set (LDS) and Centers for Medicare and Medicaid Services (CMS) 2019 Impact File. Multivariate models of hospital cost of care, length of stay, and discharge destination were performed, controlling for confounders. A univariate sub-analysis of 9 revenue centers was performed. In all, 3942 patients met the inclusion criteria. The mean cost of elective single-level cervical fusion for myelopathy was $18,084±10,783, and the mean length of stay was 2.45±2.95d. On multivariate analysis, ACDF was independently associated with decreased cost of $5,814 ( P <0.001), shorter length of stay by 1.1 days ( P <0.001), and decreased risk of nonhome discharge destination by 58% (adjusted odds ratio: 0.422, P <0.001).On sub-analysis of 9 revenue centers, medical/surgical supply ($10,497, 44%), operating room charges ($5401, 23%), and accommodations ($3999, 17%) were the largest drivers of charge differences. Single-level elective primary ACDF for DCM was independently associated with decreased cost, decreased hospital length of stay, and a lower rate of nonhome discharge compared with PCDF. Medical and surgical supply, operating room, and accommodation differences between ACDF and PCDF are potential areas for intervention. Increased granularity in reimbursement structures is warranted to prevent the creation of disincentives to the treatment of patients with DCM with pathology that is better addressed with PCDF. Level-III Retrospective Cohort Study.

With the use of anterior cervical discectomy and fusion (ACDF) expected to rise by 13.3% from 2020 to 2040, the increased usage of interbody cages with integral anterior fixation prompted a Centers for Medicare & Medicaid Services (CMS) review, which resulted in coding changes affecting anterior instrumentation documentation. CMS determined that Current Procedural Terminology (CPT) code 22845 should not be used to report integrated instrumentation (plate) with an interbody device, and if additional anterior instrumentation (e.g., plates and screws) is placed with an integrated interbody device, then a 59 modifier should be used. There is sparse literature examining the trends of ACDF without and with additional anterior instrumentation after the 2015 CMS audit. Therefore, this study aimed to evaluate the trends of single-level subaxial ACDF utilization from 2011 to 2019 to determine whether the 2015 CMS audit influenced the documented usage of additional anterior instrumentation. A retrospective cohort study was performed using the commercially available database PearlDiver. Patient records were queried from 2011 to 2019 for single-level subaxial ACDF without (CPT code 22551) and with (CPT codes 22551 + 22845) instrumentation. Cochran-Armitage trend analyses were performed to evaluate the hypothesis that ACDF with additional anterior instrumentation decreased over the given time period. Between 2011 and 2019, the total number of single-level ACDFs decreased from 6202 to 4402. From 2011 to 2015, an average of 6240 patients per year underwent single-level subaxial ACDF; of those, 950 patients (15.2%) had ACDF without instrumentation and 5290 patients (84.8%) had ACDF with instrumentation. In 2016, the total number of single-level subaxial ACDFs decreased to 5525, with 1006 patients (18.2%) receiving no instrumentation and 4519 patients (81.8%) receiving instrumentation. From 2017 to 2019, an average of 4283 patients per year underwent a single-level subaxial ACDF; of these, 1280 (29.9%) had no instrumentation and 3003 (70.1%) had instrumentation (all p < 0.0001). From 2015 to 2019, single-level ACDF without instrumentation significantly increased by 91.5% and ACDF with anterior instrumentation significantly decreased by 18.1%. The 2015 CMS audit of interbody cages and anterior instrumentation coding (CPT code 22845) may account for the decreased documentation of anterior instrumentation in the 9-year period. Understanding CMS auditing could help surgeons perceive changes in practice patterns that may lead to a more thorough evaluation of patient outcomes, cost, and overall value.

Over the past 2 years, the COVID-19 pandemic has impacted the entire health-care profession, and spinal surgery had to adjust along with it. Although it may take years to truly assess the overall effect, early trends have clearly pointed toward a patient demand for telemedicine. Additionally, as COVID strained our hospitals and diverted critical resources away from elective surgical procedures, non-time-sensitive cases have been increasingly pushed out to outpatient surgical centers. Decreased inpatient elective surgical capability has also forced more patients to pursue extended nonoperative treatment modalities. Although it remains too early to determine the long-term impact of these shifts, we expect future studies to examine these issues extensively. This annual update on spine surgery includes an examination of peer-reviewed literature for all spinal conditions, in addition to abstracts presented at annual society meetings, over the past year. We chose these articles due to their potential to impact and advance our profession, with a preference toward the highest levels of evidence. Spondylotic Cervical Myelopathy Several interesting studies published recently added to our understanding of optimal surgical treatment for spondylotic cervical myelopathy. In the Cervical Spondylotic Myelopathy Surgical (CSM-S) randomized clinical trial, Ghogawala et al. compared the impact of anterior surgery with that of posterior surgery on patient outcomes1. In a select population in which clinical equipoise existed (exclusion of patients with kyphosis of >5°, ossification of the posterior longitudinal ligament, or segmental kyphotic deformity), 1-year and 2-year Short Form-36 (SF-36) Physical Component Summary (PCS) scores were not different between the 2 groups. The authors did identify a higher complication rate in the anterior surgery group, with dysphagia predominating. The major complication rates did not differ. Interestingly, in the nonrandomized analysis comparing laminoplasty, posterior cervical fusion, and anterior cervical fusion, the patients who underwent laminoplasty fared significantly better in physical function, complication rate, and resource utilization. Posterior cervical fusion is more commonly performed in the United States, and a recent study demonstrated that laminoplasty is likely underutilized despite growing evidence for improved performance metrics2. Current literature has mixed results with regard to determination of the optimal lower instrumented vertebra (LIV) in long posterior cervical fusions. In addressing the question of crossing the cervicothoracic junction, Truumees et al.3 evaluated patient-reported outcomes, radiographic outcomes, and revision rates in fusions stopping at C6/7 or T1/2 in a retrospective analysis of 264 patients with at least a 2-year follow-up. Patient-reported outcome measures improved equally in both groups. Radiographic outcomes were similar between groups, with both groups demonstrating similar improvement in cervical lordosis. The study did not detect a difference in revision rates, but was not powered to do so. Patients who underwent fusions into the thoracic spine did have more blood loss and longer operative time. Similarly, in a retrospective cohort study with a 4-year follow-up, Guppy et al. did not identify a difference in reoperation rates for adjacent segment disease4 or pseudarthrosis5 when cervical fusions were stopped at C7 or T1/T2. In the absence of extenuating factors, stopping at C7 may be a reasonable option given the lower morbidity and complication rate, although further work is needed in this area. Cervical Radiculopathy Numerous studies have been published comparing cervical disc arthroplasty with anterior cervical discectomy and fusion (ACDF). However, many of these studies may have been biased by industry sponsorship and a lack of blinded outcome assessment. The Norwegian Cervical Arthroplasty Trial (NORCAT) was designed as a blinded and randomized clinical trial of 136 patients comparing patient-reported outcomes after ACDF or cervical disc arthroplasty for single-level disease6. The patients and surgeons were blinded, with the treatment arm revealed to the surgeon only after neurologic decompression was completed. Both groups demonstrated a significant improvement in the Neck Disability Index (NDI) at 5 years, without a difference observed between groups. Secondary outcomes, including neck pain, arm pain, and adjacent segment disease, were not different between groups. The reoperation rate was not significantly different between groups, and nearly all reoperations were at the index level. Only 1 patient underwent reoperation for adjacent segment disease at 5 years. This study demonstrates that clinical outcomes are likely independent of implant choice; however, the effect on adjacent segment disease needs to be addressed with longer-term follow-up. The 10-year Investigational Device Exemption (IDE) trial data for the Bryan and Mobi-C cervical disc arthroplasty devices are now available. In a study comparing adverse events between the Bryan cervical disc arthroplasty and ACDF, Loidolt et al. demonstrated a similar rate of adverse events over a 10-year period7. The rate of revision surgery at the index level was not significantly different between the 2 groups. The rate of adjacent level surgery in the ACDF group trended higher (15.8% compared with 9.7%) but did not reach significance at 10 years. Additionally, the 10-year outcomes from the Mobi-C IDE trial were published8. This study was limited by lack of an ACDF control group and had an approximately 73% follow-up rate from the original cohort. At 10 years, the authors identified a rate of revision surgery of 5.1% at the index level and 4.3% at the adjacent level. No serious adverse events were reported between 7 and 10 years. One of the most common symptoms after anterior cervical surgery is dysphagia. In a meta-analysis of 7 randomized controlled trials, Garcia et al. evaluated the dysphagia rate after ACDF with prophylactic administration of local or intravenous corticosteroid9. The study provides moderate-quality evidence that the administration of corticosteroids reduces the dysphagia rate and severity after ACDF. A subgroup of studies on the pseudarthrosis rate did not identify a difference. No infections were reported in this meta-analysis. In a recent, well-designed, randomized, and double-blinded controlled trial, Kim et al.10 corroborated these results: after undergoing multilevel ACDF, patients received retropharyngeal corticosteroid or placebo. Dysphagia was assessed with validated outcomes. The corticosteroid group had significantly better scores at all time points up to 1 month. These results suggest that corticosteroid administration likely reduces dysphagia rates, although the effect on pseudarthrosis remains to be fully elucidated. Lumbar Disc Herniation and Lumbar Degenerative Conditions Lumbar disc herniation remains a common clinical problem11. Several recent studies have examined options for the management of lumbar disc herniation. In a randomized controlled trial, Wilby et al. compared microdiscectomy with transforaminal epidural corticosteroid injection in patients with persistent radicular pain for <1 year secondary to disc herniation12. The authors found that there were no significant differences in pain scores between the epidural injection group and the surgery group, although 18% of the injection group underwent a surgical procedure prior to the completion of the study. The authors also posited that a surgical procedure is less cost-effective than an epidural injection, although this work is ongoing. In a systematic review and meta-analysis, Wei et al. compared open microdiscectomy, microendoscopic discectomy, percutaneous endoscopic discectomy, tubular discectomy, and percutaneous discectomy13. The authors found no significant differences between most approaches, except that percutaneous endoscopic discectomy had the best safety and efficacy, although this review was limited by the heterogeneity of the included studies. Ran et al. compared computed tomography (CT)-navigated percutaneous endoscopic discectomy with open microdiscectomy in 68 patients and found that the percutaneous discectomy group reported less postoperative back pain and the percutaneous approach generated lower serum markers of muscle trauma14. In a systematic review and meta-analysis, Gadjradj et al. found that moderate-quality evidence supports percutaneous transforaminal endoscopic discectomy as an equivalent treatment to open microdiscectomy, but there is a paucity of high-quality evidence comparing the 2 approaches15. Additionally, the topic of annular repair or other implants to reduce reherniation rates has been reexamined in the last 2 years. In a systematic review, Rickers et al. found a trend toward improved outcomes with annular repair. In contradistinction to the prior study, the authors also found that percutaneous discectomy performed the worst of all current surgical approaches, although, overall, there were no significant differences between treatments16. Additionally, the risk of bias was high in 15 of the 32 included studies. The debate with regard to the optimal management protocol for lumbar degenerative spondylolisthesis has continued lately. Heemskerk et al.17 compared open transforaminal lumbar interbody fusion (TLIF) and minimally invasive surgery (MIS)-TLIF for patient-reported outcomes, and Droeghaag et al.18 compared open TLIF and MIS-TLIF for cost-effectiveness. Heemskerk et al. found that MIS-TLIF and open TLIF had equivalent outcomes at the 2-year follow-up; Droeghaag et al. found that MIS-TLIF is more cost-effective than open TLIF. These results suggest that MIS-TLIF may be an important tool in the long-term management of lumbar degenerative spondylolisthesis. However, in a meta-analysis of 7 studies, Zhang et al. found that oblique lateral interbody fusion with supplementary posterior fixation yielded better improvements in symptoms compared with MIS-TLIF and was associated with a shorter operative time19. Furthermore, the type of posterior fixation for lumbar fusion remains controversial. In a systematic review and meta-analysis, Chang et al. compared traditional pedicle screws with cortical-based trajectory screws for the treatment of lumbar degenerative spondylolisthesis in patients who underwent interbody fusion20. The authors found that cortical screws were associated with decreased operative time and less blood loss during the surgical procedure, but the overall fusion rates were similar at 1 year. Additionally, Zhu et al. performed a systematic review and meta-analysis comparing MIS-TLIF and endoscopic TLIF, which demonstrated the noninferiority of the endoscopic approach compared with traditional minimally invasive techniques21. The applications of navigation and robotics continue to rapidly expand in the field of spinal surgery. Fu et al.22 and Zhou et al.23 both performed meta-analyses comparing the freehand placement of pedicle screws with robotic-assisted placement. Both studies found significant improvements in pedicle screw accuracy, including reduced violation of the cephalad facet joint and intraoperative radiation dose, with robotic assistance, although revision rates for screw malpositioning were similar in the latter article. Klingler et al. performed a randomized trial of fluoroscopically assisted MIS-TLIF and navigated TLIF and found that the type of navigation used in the study did not significantly reduce radiation exposure to the surgeon, while simultaneously increasing radiation exposure to the patient24. Therefore, the role of navigation and robotics is still being developed. There has also been increasing interest in single-position prone lateral lumbar interbody fusion as an option for patients requiring surgical stabilization for spondylolisthesis. Walker et al. performed a retrospective review of 30 patients with spondylolisthesis undergoing either prone or lateral decubitus lateral interbody fusion with posterior instrumentation25. The authors found that the prone position yielded significantly improved segmental lordosis compared with the traditional position. Additionally, Guiroy et al. performed a systematic review comparing these approaches and found that single-position lateral decubitus trended toward shorter operative time and hospital stay, although only 4 studies were included26. Interestingly, in a separate systematic review and meta-analysis, Mills et al. examined lateral decubitus compared with the prone position without repositioning and found that the single-position lateral decubitus reduced operative time and radiation exposure compared with the prone position, and the improvement in segmental lordosis was higher in the prone group27. However, pedicle screws placed using the lateral decubitus position had a higher rate of complications. Perioperative Pain Management There has been increasing interest in the utilization of local or regional anesthesia for pain control in patients undergoing lumbar spinal surgery. Erector spinae plane blockade continues to gain traction in this regard. In randomized controlled trials, Jin et al.28 examined the efficacy of an erector spinae plane block in patients undergoing lumbar laminoplasty, and Zhu et al.29 and Goel et al.30 examined the efficacy of an erector spinae plane block in patients undergoing single-level lumbar fusion. The authors found that erector spinae plane blockade resulted in significantly reduced postoperative pain scores, reduced opioid consumption, and higher patient satisfaction, suggesting that erector spinae plane blockade should become more routinely utilized in the perioperative period. Liposomal bupivacaine injection is an additional multimodal pain management technique to reduce postoperative pain and opioid consumption. Nguyen et al. performed a systematic review of retrospective cohort studies and randomized controlled trials investigating this technique and found that lower-quality evidence supports its use and moderate-quality studies were equivocal31. The authors maintained that higher-quality studies are needed before the efficacy of this technique can be fully appreciated. Multimodal anesthesia and various enhanced recovery after surgery (ERAS) postoperative pain management protocols have been developed to expedite patient recovery and improve satisfaction after spinal surgery. Recently, there have been several high-quality studies adding to the data on this topic. Soffin et al. published a trial of 56 patients randomized to either the ERAS protocol after lumbar fusion or traditional postoperative pain management, finding decreased opioid consumption and improved patient-reported pain scores in the immediate postoperative period with the ERAS protocol32. However, significant clinical impact was not proven with the ERAS protocol, which was possibly related to the small sample size. In a randomized controlled trial, Kraiwattanapong et al. similarly evaluated multimodal drug infiltration in the postoperative wound bed, demonstrating that this technique reduced postoperative pain scores and opioid consumption33. Sharaf et al. performed a randomized controlled trial comparing postoperative physical therapy with and without neural mobilization in patients who underwent lumbar decompression for stenosis; the authors found that the addition of neural mobilization improved outcomes across all patient-reported outcome measures34. Lastly, Ma et al. performed a prospective randomized trial evaluating the utility of postoperative spinal orthoses after MIS-TLIF35. The authors found that the use of a postoperative orthosis had no significant effect on the Oswestry Disability Index (ODI) or visual analog scale pain score at 6 or 12 months after MIS-TLIF. Additionally, the orthosis had no effect on the fusion rate at the final follow-up. Adult Spinal Deformity Surgical decision-making for patients with adult spinal deformity is complex. In several recent studies, authors have examined the risk-and-benefit calculation that aids our surgical indications, patient optimization, and preoperative counseling. The Prospective Evaluation of Elderly Deformity Surgery (PEEDS)36 study illustrates the potential benefit of spinal deformity surgery: this prospective, multicontinental study evaluated disability (ODI) in patients ≥60 years of age who underwent spinal deformity surgery. The authors demonstrated that, after an initial recovery period, 70% of patients experienced at least 10% improvement from their baseline disability, which was sustained at 2 years. Meanwhile, approximately 25% of patients reported no change from baseline and approximately 5% of patients reported worsening of the disability. Importantly, although there was an overall significant improvement in disability, the mean ODI of 27% at 2 years was still worse than normative values, and was consistent with moderate disability. This article also stratified the shift in ODI based on preoperative ODI deciles, which is a useful counseling tool for shared decision-making. Similar findings were identified in the 5-year outcomes reported by the Scoli-RISK-1 Study Group37. This study was limited by a 5-year follow-up rate of 28%, but identified a significant improvement in patient-reported outcomes, with 62% of patients having a clinically meaningful improvement in the ODI score. Numerous studies have shown the complication profile of deformity surgery. The 5-year results from the Scoli-RISK-1 Study Group demonstrated worse lower-extremity motor scores in 9.3% of patients who were available for follow-up at 5 years38. This rate was improved from 14% at the time of hospital discharge and was unchanged from 2 years postoperatively. In a recent study, Lakomkin et al.39 helped to contextualize the surgical invasiveness of deformity surgery by comparing it with other major operations. Using a variation of the validated Postoperative Morbidity Survey score, the authors added length of hospital stay and operative time to develop the novel Surgical Invasiveness and Morbidity Score (SIMS). Using the National Surgical Quality Improvement Program (NSQIP) database and controlling for comorbidities, the authors compared SIMS across major surgical procedures. Adult spinal deformity surgery fared better than coronary artery bypass grafting, abdominal aortic aneurysm repair, and cystectomy, performed similarly to mitral valve replacement, and was, overall, worse than prostatectomy, total shoulder arthroplasty, and hip fracture fixation. This study provides an intuitive counseling tool for patients considering adult spinal deformity surgery. Several studies have shown the importance of patient frailty as a predictor of outcomes and complications. Passias et al.40 demonstrated that frailty was independent of chronological age in predicting positive outcomes in adult spinal deformity surgery. Patients ≥70 years of age who were not frail fared better than elderly patients who were frail or severely frail. Gum et al.41 demonstrated that the cost of quality-adjusted life-year (QALY) was impacted more by patient frailty than by surgical invasiveness. Frail and severely frail patients had significantly and incrementally higher costs per QALY than non-frail patients. Surgical invasiveness did not have a substantial impact on cost per QALY. The authors recommended focusing on patient optimization with respect to modifiable risk factors to improve cost optimization. These studies help to understand the risk and benefit of adult spinal deformity surgery and provide an increased awareness of patient factors that may impact outcomes. Nonoperative Treatments Spine surgery continues to evolve with the rest of the surgical profession, and, as many have proven, high-quality randomized controlled trials are difficult to perform with surgical procedures. In contrast, our interventional pain colleagues may be better positioned to conduct studies within this gold standard of evidence-based medicine. Their ability to do so, coupled with an increase in the nonoperative treatment environment, has created an exponential growth across the United States at a time when our patients were hesitant to seek hospital-based care. A thorough discussion of all available pain management procedures is beyond the scope of this update, but we believe that it is particularly important that all orthopaedic surgeons understand the basics behind these procedures and the early evidence to support their use. We do advise the reader that each of the studies in this section was industry-funded. The minimally invasive lumbar decompression (mild) procedure is approved by the U.S. Food and Drug Administration (FDA) for the treatment of neurogenic claudication and gained approval for reimbursement by the U.S. Centers for Medicare & Medicaid Services (CMS) in 2017. The procedure uses a small portal to remove part of the lamina and ligamentum flavum using radiographic assistance. Most recently, in 2021, Deer et al. published the 6-month results of a randomized controlled trial comparing the mild procedure with conventional medical management and found the mild procedure to have superior results, albeit in very early results42. Multiple interspinous devices are currently available on the market, and we have seen an increased use among our pain management colleagues. These devices have an established role in the management of neurogenic claudication, but their specific indications continue to evolve. Schenck et al. recently reported the results of their 5-year randomized controlled trial of interspinous devices compared with decompressive surgery and found similar results, but with a higher risk of reoperation within the first 2 years following use of interspinous devices43. Intraosseous basivertebral nerve ablation procedure was approved by the FDA in 2016 for the treatment of chronic low back pain in patients with disc degeneration and Modic end plate changes. This procedure has recently demonstrated positive results. Fischgrund et al. performed a double-blinded randomized trial, finding that the ablation of the basivertebral nerve yielded continued improvement in pain and function at a mean of 6.4 years postoperatively in this challenging patient population44. Telemedicine in Spine Surgery With the COVID-19 nearly the entire spine a in surgical procedures and an increase in The of and there has been exponential growth within the most of the literature on the and with articles evaluating the long-term outcomes of so. Several authors validated the performance of the with an on the neurologic Similar to the rest of the the spine to back with Over the past 2 years, we have different and expect to continued growth of this important advance forced by the Although this has been a of the it not the among colleagues in At the time of this all future society are currently to be at the Spine in in the Cervical Spine in in the in in the Lumbar Spine in in the Spine in and the of in in The of a of recently published studies related to the that received a higher of In addition to articles in this update, 6 other articles to spine surgery are to this review after the standard with a each article to help further in an evidence-based in this area. with or without fusion in degenerative lumbar spondylolisthesis. In a noninferiority study, et al. evaluated all patients with lumbar degenerative spondylolisthesis with a of who were randomized to either decompression or decompression and fusion. The of and evidence of a were not into their The outcome was an improvement of the ODI score by At 2 years, an equivalent of patients had a clinically important improvement of the ODI in the group and in the decompression and fusion at 2 years, reoperation rates trended higher in the group at than in the decompression and fusion group at but this difference was not This study was limited by the heterogeneity of the included as the and of degenerative spondylolisthesis were not included in the reoperation rates be useful in understanding the of decompression in the of degenerative spondylolisthesis. this study useful to the debate fusion for degenerative but of the of patients who benefit most from decompression and fusion compared with decompression Current of adjacent segment following lumbar fusion a systematic review and meta-analysis of recent Spine The risk of adjacent segment degeneration at adjacent levels to lumbar fusion remains a clinical surgery has been developed to this et al. performed a systematic review comparing these and the reported rate of adjacent segment The authors found no significant differences in adjacent segment disease or reoperation between groups, although the analysis demonstrated lower of adjacent segment degeneration in the The of included studies was there still is no on surgery decreased adjacent segment a systematic review and meta-analysis comparing Spine In a systematic review and meta-analysis, et al. compared stabilization with fixation for lumbar had improved length of stay, operative and blood loss but worse loss of deformity at final Patient-reported outcomes were not significantly different between groups. The literature remains on which surgical approach is of arthroplasty fusion for patients with cervical a randomized clinical et al. performed a randomized clinical trial comparing single-level ACDF with cervical disc Patients were blinded to and surgeons were blinded to treatment neurologic decompression was completed. The outcome was the and the secondary outcomes were arm and neck pain scores, of reoperation rate, and adjacent segment There were 136 patients with follow-up at 5 years. scores significantly improved in both groups, without a difference observed between groups. No differences were in reoperation rate or adjacent segment This study demonstrated that neck disability scores were not significantly different between groups within 5 years. for adjacent segment disease and reoperation longer-term follow-up. of to surgical after spine surgery: a systematic review and meta-analysis. Pain et al. performed a systematic review and meta-analysis of studies only 6 were randomized controlled and found that the addition of in the wound after spinal as as and a of the 2 yielded significant in surgical corroborated by this systematic review, reduce after spine surgery. in a systematic review and meta-analysis of randomized controlled Spine et al. performed a systematic review and meta-analysis of the available literature comparing the use of orthoses with no in the management of The authors found that, overall, there were no significant differences between the group orthoses and the group with no with regard to pain scores or radiographic and recommended that treatment of not These findings studies on the topic.

Retrospective cohort study. To analyze the effect of hyperlipidemia (HLD) on postoperative complications in patients who underwent anterior cervical discectomy and fusion (ACDF). ACDF represents the standard procedure performed for focal anterior nerve root or spinal cord compression with low complication rates. HLD is well known as a risk factor for major complications after vascular and transplant surgery, and orthopedic surgery. To date, there have been no studies on HLD as a risk factor for cervical spine surgery. Patients who underwent ACDF from 2010 through quarter 3 of 2020 were enrolled using the MSpine subset of the PearlDiver Patient Record Database. The patients were divided into single-level ACDF and multilevel ACDF groups. In addition, each group was divided into subgroups according to the presence or absence of HLD. The incidence of surgical and medical complications was queried using relevant International Classification of Disease and Current Procedural Terminology codes. Charlson Comorbidity Index was used as a broad measure of comorbidity. χ 2 analysis, with populations matched for age, sex, and Charlson Comorbidity Index, was performed. A total of 24,936 patients who underwent single-level ACDF and 26,921 patients who underwent multilevel ACDF were included. In the multilevel ACDF group, wound complications were significantly higher in the patients with HLD. Among medical complications, myocardial infarction, renal failure, and urinary tract infection/urinary incontinence were significantly higher in the patients with HLD in both groups. Revision surgery and readmission were significantly higher in the patients with HLD who underwent multilevel ACDF. In patients who underwent ACDF, several surgical and medical complications were found to be higher in patients with HLD than in patients without HLD. Preoperative serum lipid concentration levels and management of HLD should be considered during preoperative planning to prevent postoperative complications in patients undergoing ACDF.

Friday, September 28, 2018 10:30 AM–12:00 PM abstracts: complications of cervical spine surgery: 160. Obstructive sleep apnea increases the risk of postoperative pulmonary complications following one- or two-level cervical fusion: a retrospective database review study

P115. Analysis of 90-day readmissions across hospital size: Risk factors for readmission in single level anterior cervical discectomy and fusion

Ambulatory anterior cervical discectomy and fusion is associated with a higher risk of revision surgery and perioperative complications: an analysis of a large nationwide database