Comparing clinical and radiological outcomes between single-level OLIF and XLIF: A systematic review and meta-analysis.

Background Context: Oblique lumbar interbody fusion (OLIF) and extreme lateral interbody fusion (XLIF) are 2 popular minimally invasive spinal fusion techniques with unique approach-related complication profiles. Accordingly, patient-specific anatomical factors, such as vascular anatomy or iliac crest height, greatly influence which technique to use. Previous studies comparing these approaches do not account for the inability of XLIF to access the L5-S1 disc space and therefore do not exclude this level in their analysis. The purpose of this study was to compare radiological and clinical outcomes of these techniques in the L1-L5 region. Methods: A query of 3 electronic databases (PubMed, CINAHL plus, and SCOPUS) was performed, without time restriction, to identify studies that evaluated outcomes of single-level OLIF and/or XLIF between L1 and L5. Based on heterogeneity, a random effects meta-analysis was performed to evaluate the pooled estimation of each variable between the groups. An overlap of 95% confidence intervals suggests no statistically significant difference at the p<.05 level. Results: A total of 1,010 patients (408 OLIF, 602 XLIF) were included from 24 published studies. Improvements in disc height (OLIF: 4.2 mm; XLIF: 5.3 mm), lumbar segmental (OLIF: 2.3°; XLIF: 3.1°), and lumbar lordotic angles (OLIF: 5.3°; XLIF: 3.3°) showed no significant difference. The rate of neuropraxia was significantly greater in the XLIF group at 21.2% versus 10.9% in the OLIF group (p<.05). However, the rate of vascular injury was higher in the OLIF cohort at 3.2% (95% CI:1.7-6.0) as compared to 0.0 (95% CI: 0.0-1.4) in the XLIF cohort. Improvements in VAS-b (OLIF: 5.6; XLIF: 4.5) and ODI (OLIF: 37.9; XLIF: 25.6) scores were not significantly different between the 2 groups. Conclusions: This meta-analysis demonstrates similar clinical and radiological outcomes between single-level OLIF and XLIF from L1 to L5. XLIF had significantly higher rates of neuropraxia, whereas OLIF had greater rates of vascular injury.

The 5-factor modified Frailty Index (mFI-5) predicts adverse outcomes after elective Anterior Lumbar Interbody Fusion (ALIF).

Background: The 5-factor modified frailty index (mFI-5) has been shown to be a concise and effective tool for predicting adverse events following various spine procedures. However, there have been no studies assessing its utility in patients undergoing anterior lumbar interbody fusion (ALIF). Therefore, the aim of this study was to analyze the predictive capabilities of the mFI-5 for 30-day postoperative adverse events following elective ALIF. Methods: The National Surgical Quality Improvement Program (NSQIP) database was queried from 2010 through 2019 to identify patients who underwent elective ALIF using Current Procedural Terminology (CPT) codes in patients over the age of 50. The mFI-5 score was calculated using variables for hypertension, congestive heart failure, comorbid diabetes, chronic obstructive pulmonary disease, and partially or fully dependent functional status which were each assigned 1 point. Univariate analysis and multivariate logistic regression models were utilized to identify the associations between mFI-5 scores, and 30-day rates of overall complications, readmissions, reoperations, and mortality. Results: 11,711 patients were included (mFI-5=0: 4,026 patients, mFI-5=1: 5,392, mFI-5=2: 2,102, mFI-5=3+: 187. Multivariate logistic regression revealed that mFI-5 scores of 1 (OR: 2.2, CI: 1.2-4.2, p=0.02), 2 (OR: 3.6, CI: 1.8-7.3, p<0.001), and 3+ (OR: 7.0, CI: 2.5-19.3, p<0.001) versus a score of 0 were significant predictors of pneumonia. An mFI-5 score of 2 (OR: 1.3; CI: 1.01-1.6, p=0.04), and 3+ (OR: 1.9; CI: 1.1-3.1; p=0.01) were both independent predictors of related readmissions. An mFI score of 3+ was an independent predictor of any complication (OR: 1.5, CI: 1.01-2.2, p=0.004), UTI (OR: 2.4, CI: 1.1-5.2, p=0.02), and unplanned intubation (OR: 4.5, CI: 1.3-16.1, p=0.02). Conclusions: The mFI-5 is an independent predictor for 30-day postoperative complications, readmissions, UTI, pneumonia, and unplanned intubations following elective ALIF surgery in adults over the age of 50.

Minimally Invasive Transforaminal Lumbar Interbody Fusion (MI-TLIF): A Video Technique Guide.

Background: Minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) has been established as an excellent alternative to the traditional open approach for the treatment of degenerative conditions of the lumbar spine1-3. Description: The procedure is performed with the patient under general anesthesia and on a radiolucent table in order to allow for intraoperative fluoroscopy. The procedure is performed through small incisions made over the vertebral levels of interest, typically utilizing either a fixed or expandable type of tubular dilator, which is eventually seated against the facet joint complex4. A laminectomy and/or facetectomy is performed in order to expose the disc space, and the ipsilateral neural elements are visualized5. The end plates are prepared, and an interbody device is placed after the disc is removed. Pedicle screws and rods are then placed for posterior fixation. Alternatives: Nonoperative alternatives include physical therapy and corticosteroid injections. Other operative techniques include open TLIF or other types of lumbar fusion approaches, such as posterior lumbar interbody fusion (PLIF), anterior lumbar interbody fusion, lateral or extreme lateral interbody fusion, or oblique lumbar interbody fusion. Rationale: Open TLIF was developed in order to obtain a more lateral approach to the lumbar disc space than was previously possible with PLIF. The goal of this was to minimize the amount of thecal-sac and nerve-root retraction required during PLIF4. Additionally, as the number of patients who required revision after PLIF increased, the need arose for an approach to the lumbar spine that circumvented the posterior midline scarring from previous PLIF surgical sites6. MI-TLIF was introduced to reduce the approach-related paraspinal muscle damage of open TLIF5. Indications for MI-TLIF include most degenerative pathology of the lumbar spine, including disc herniation, low-grade spondylolisthesis, and spinal and foraminal stenosis7. However, MI-TLIF allows for less robust correction of deformity than other minimally invasive approaches; therefore, MI-TLIF may not be as effective in cases of substantial spinal deformity or high-grade spondylolisthesis8. Expected Outcomes: MI-TLIF results in significantly less blood loss, postoperative pain, and hospital length of stay compared with open TLIF1-3. Although some studies have suggested increased operative time for MI-TLIF9,10, meta-analyses have shown comparable operative times between the 2 techniques1-3. It is thought that the discrepancy in reported operative times is the result of a learning curve and that, once that is overcome, the difference in operative time between the 2 techniques becomes minimal11,12. One disadvantage of MI-TLIF that has remained constant in the literature is its increased intraoperative fluoroscopy time compared with open TLIF3,13. The complication rate has largely been found to be equivalent between open and MI-TLIF1-3 or slightly lower with MI-TLIF14, especially in the hands of an experienced surgeon15. Finally, the fusion rate and improvement in patient outcome scores have also been found to be largely equivalent1-3. Important Tips: We suggest placing the ipsilateral pedicle screw after the interbody cage has been inserted.Fully visualize the Kambin triangle16 prior to performing the facetectomy. Protect the exiting and traversing nerve roots by placing small cottonoids around them and retracting delicately.Bone removed during facetectomy can be utilized as autograft for the interbody cage.Avoid removing pedicle bone during decompression.If central stenosis is present, the neural decompression should be extended medial to the epidural fat so that the dura mater can be visualized all of the way to the contralateral pedicle.Perform an adequate end plate preparation prior to interbody insertion while being mindful to avoid injuring the end plate, to minimize the risk of future cage subsidence.Confirm correct placement of the interbody device on intraoperative fluoroscopy.If bone morphogenic protein is utilized, be careful not to pack too much posteriorly as this may cause nerve irritation. Acronyms and Abbreviations: TLIF = transforaminal lumbar interbody fusionMI-TLIF = minimally invasive TLIFPLIF = posterior lumbar interbody fusionALIF = anterior lumbar interbody fusionLLIF = lateral lumbar interbody fusionXLIF = extreme lateral interbody fusionOLIF = oblique lumbar interbody fusionDLIF = direct lateral interbody fusionMRI = magnetic resonance imagingA/P = anteroposteriorEMG = electromyographicBMP = bone morphogenic proteinXR = x-ray (radiograph)OTC = over the counterDVT = deep vein thrombosisPE = pulmonary embolismMI = myocardial infarctionMIS = minimally invasive surgeryOR = operating roomLOS = length of stayVAS = visual analog scaleODI = Oswestry Disability IndexM-H = Mantel-HaenszelRR = risk ratioCI = confidence intervalNSAIDs = nonsteroidal anti-inflammatory drugs.

Two-Attending Surgeon Teams Improve Outcomes of Single-Level Anterior Cervical Discectomy and Fusion.

Given the shift toward value-based healthcare, strategies that decrease risk in commonly performed procedures such as anterior cervical discectomy and fusion (ACDF) are of interest. The objective of this study was to analyze the effect of a two-attending surgeon team on the outcomes of patients undergoing single-level ACDF. A retrospective matched-cohort study of patients undergoing single-level ACDF for degenerative cervical spondylosis, with minimum 2-year follow-up was performed. Patients were subdivided into two cohorts: cases with procedures performed by one attending surgeon assisted by a resident physician and cases with procedures performed by an attending surgeon with another attending surgeon as first-assist. Patients were matched by age, sex, body mass index, smoking status, American Society of Anesthesia grade and Charlson Comorbidity Index. Perioperative data and complications were compared. Standard binomial and categorical comparative analysis were performed. Forty-two patients were included (21 in each group). There were 22 males and 20 females, with a mean age of 47.7 years and mean follow-up of 43.4 months. There were no differences in any demographic variable between groups, indicating successful matching. Cohort B had decreased anesthesia time (114.9 vs. 157.1 minutes, P < 0.001), operative time (58.1 vs. 98.9 minutes, P < 0.001) and blood loss (14.8 vs. 24.3 mL, P = 0.012). There were no significant differences in terms of post-operative complications including dysphagia, wound infection, neurologic or cardiovascular related complications. A two-attending surgeon team significantly reduces anesthesia time, surgical time, and blood loss in single-level ACDF procedures without an increase in complications or a decrease in fusion rates.

Obesity Does Not Adversely Affect Long-term Outcomes of Minimally Invasive Transforaminal Lumbar Interbody Fusion: A Matched Cohort Analysis.

Minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) is an established technique for the treatment of degenerative spine disease. The larger body habitus of obese patients increases the intraoperative complexity of MI-TLIF. Therefore, it is unclear whether this procedure is appropriate for this population. The goal of this study was to compare postoperative outcomes for obese patients vs nonobese patients undergoing MI-TLIF through a matched cohort analysis. A retrospective review was performed to identify patients who underwent MI-TLIF at a single institution with a minimum follow-up of 5 years. Patients were divided into 2 cohorts: nonobese (body mass index <30 kg/m2) and obese (body mass index ≥30 kg/m2). Each cohort was matched for age, sex, and levels operated. Perioperative data and patient-reported outcomes were compared. Radiographic outcomes were measured at final follow-up. Standard binomial and categorical comparative analyses were performed. A total of 148 patients were included. Of obese patients, 17.6% required revision surgery compared with 16.2% of nonobese patients (P=.826). Both cohorts had a similar proportion of pelvic incidence-lumbar lordosis mismatch correction (P=.780). Mean change in functional outcome scores for each cohort did not differ significantly. Obese patients had clinically minor but statistically significantly greater blood loss and longer operative times than nonobese patients (P<.001). Obese and non-obese patients undergoing MI-TLIF showed no long-term differences in revision rate, radiologic outcome, or functional outcome after long-term follow-up. Obese patients had slightly greater blood loss and longer operative times. Our findings suggest that MI-TLIF is an appropriate alternative to traditional open lumbar fusion for obese patients. [Orthopedics. 2022;45(4):203-208.].

Long-term Outcomes of Minimally Invasive Lateral Lumbar Interbody Fusion in the Treatment of Adult Scoliosis.

The literature has shown the importance of long-term follow-up for adults with scoliosis treated surgically because complication and revision rates are high. The goal of this study was to determine long-term outcomes and complications of lateral lumbar interbody fusion (LLIF) with posterior instrumentation for adult patients with scoliosis. A retrospective review of our institution's database was performed to identify adult patients with scoliosis treated with LLIF between 2008 and 2013 with a minimum follow-up of 4 years. Medical records were reviewed for complications and revisions. Pre- and postoperative deformity Cobb angle measurements were taken as well as pelvic incidence (PI) and lumbar lordosis (LL). Functional outcome scores, including Oswestry Disability Index and visual analog scale score for back and leg pain, were assessed preoperatively and at follow-up. Standard binomial and categorical comparative analysis was performed. The 26 patients included had a mean age of 62 years, mean follow-up of 89 months, and mean of 1.8 levels per operation. Four patients (15.4%) required revisions. Mean deformity Cobb angle was 26° preoperatively and 14° postoperatively. Mean PI-LL mismatch was 11.7° preoperatively and 5.9° postoperatively. Nineteen (73%) patients had a PI-LL mismatch greater than 10° preoperatively, whereas only 2 (7.7%) had a mismatch postoperatively. Improvement was seen in all functional outcome scores. Long-term clinical results of LLIF for adults with deformity showed a low proportion of revision in the treatment of a condition with an established high rate of revision. The ability to reduce pelvic mismatch may further reduce the rate of revision. In this study, LLIF resulted in improved functional outcomes and patient satisfaction. [Orthopedics. 2022;45(3):e134-e139.].

Should we bridge the cervicothoracic junction in long cervical fusions? A meta-analysis and systematic review of the literature.

OBJECTIVE: Long posterior cervical decompression and fusion (PCF) is commonly performed to surgically treat patients with multilevel cervical pathology. In cases in which constructs may necessitate crossing the cervicothoracic junction (CTJ), recommendations for appropriate caudal fusion level vary in the literature. The aim of this study was to report the clinical and radiological outcomes of multilevel PCFs ending at C7 versus those crossing the CTJ. METHODS: A systematic search of PubMed, CINAHL Plus, and Scopus was conducted to identify articles that evaluated clinical and radiological outcomes of long PCFs that ended at C7 (cervical group) or crossed the CTJ (thoracic group). Based on heterogeneity, random-effects models of a meta-analysis were used to estimate the pooled estimates and the 95% confidence intervals. RESULTS: PCF outcome data of 1120 patients from 10 published studies were included. Compared with the cervical group, the thoracic group experienced greater mean blood loss (453.0 ml [95% CI 333.6-572.5 ml] vs 303.5 ml [95% CI 203.4-403.6 ml]), longer operative times (235.5 minutes [95% CI 187.7-283.3 minutes] vs 198.5 minutes [95% CI 157.9-239.0 minutes]), and a longer length of stay (6.7 days [95% CI 3.3-10.2 days] vs 6.2 days [95% CI 3.8-8.7 days]); however, these differences were not statistically significant. None of the included studies specifically investigated factors that led to the decision of whether to cross the CTJ. The cervical group had a mean fusion rate of 86% (95% CI 71%-94%) compared with the thoracic group with a rate of 90% (95% CI 81%-95%). Of patients in the cervical group, 17% (95% CI 10%-28%) required revision surgery compared with 7% (95% CI 4%-13%) of those in the thoracic group, but this difference was not statistically significant. The proportion of patients who experienced complications in the cervical group was found to be 28% (95% CI 12%-52%) versus 14% (95% CI 7%-26%) in the thoracic group; however, this difference was not statistically significant. There was no significant difference (no overlap of 95% CIs) in the incidence of adjacent-segment disease, pseudarthrosis, or wound-related complications between groups. CONCLUSIONS: This meta-analysis suggests similar clinical and radiographic outcomes in multilevel PCF, regardless of inclusion of the CTJ. The lowest instrumented level did not significantly affect revision rates or complications. The ideal stopping point must be tailored to each patient on an individualized basis.

Comparing Mid-Term Outcomes Between ACDF and Minimally Invasive Posterior Cervical Foraminotomy in the Treatment of Cervical Radiculopathy.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To compare minimally invasive posterior cervical foraminotomy (MI-PCF) and anterior cervical discectomy and fusion (ACDF) in the treatment of unilateral cervical radiculopathy. SUMMARY OF BACKGROUND DATA: MI-PCF has been shown to be equally effective as ACDF in treating cervical radiculopathy due to foraminal stenosis and similar pathologies. Additionally, it has been hypothesized that preserving motion and avoiding fusion reduces risk for adjacent segment disease, but potentially increases risk for subsequent revision to an ACDF. With similar short-term outcomes and substantial advantages, MI-PCF may be an effective alternative to ACDF for addressing appropriate cervical pathology. METHODS: A retrospective review was performed to identify patients between 2009 and 2013 who underwent ACDF or MI-PCF with a minimum follow-up of 7 years. Demographic data was recorded. Revision rates and average time to revision between cohorts were compared. Clinical outcomes were assessed at each follow-up visit with Neck Disability Index and Visual Analog Scale for neck and Visual Analog Scale for arm pain scores. All complications were reviewed. Standard binomial and categorical comparative analysis were performed. RESULTS: A total of 251 consecutive patients were included (205 ACDF, 46 MI-PCF). Mean follow-ups for the ACDF and MI-PCF groups were 98.3 and 95.9 months, respectively. Complication rates were 2.9% and 2.2% for the ACDF and MI-PCF cohorts, respectively (P = 0.779). Revision rates were 7.8% for the ACDF cohort and 8.7% for the MI-PCF cohort (P = 0.840). Both cohorts experienced significant improvements in their clinical scores compared with their preoperative values. Final Visual Analog Scale for neck pain (ACDF: 2.6; MI-PCF: 1.6) and Visual Analog Scale for arm pain (ACDF: 1.1; MI-PCF: 0.4) scores differed significantly at final follow-up (P =  < 0.001; P =  < 0.001). CONCLUSION: MI-PCF is a safe and effective alternative to ACDF in the treatment of cervical radiculopathy, demonstrating substantial benefit. After final follow-up, MI-PCF demonstrated superior improvements in Visual Analog Scale scores, without increased complication or revision rates.Level of Evidence: 3.

Metal-on-metal versus metal-on-plastic artificial discs in two-level anterior cervical disc replacement: a meta-analysis with follow-up of 5 years or more.

BACKGROUND CONTEXT: Although highlighted in joint arthroplasty studies, long-term outcomes between differing biomaterial composites, such as metal-on-metal (MoM) and metal-on-plastic (MoP) in anterior cervical disc replacement (ACDR) have not been thoroughly investigated. PURPOSE: The purpose of this study was to evaluate the patient-reported clinical outcomes, overall reoperation rates, complications, and rates of ASD of MoM versus MoP artificial discs in two-level ACDR for the treatment of cervical DDD. STUDY DESIGN/SETTING: Meta-analysis and systematic review. PATIENT SAMPLE: Nine hundred eighty patients (442 MoM, 538 MoP) across seven studies. OUTCOME MEASURES: Patient reported clinical outcomes (NDI, VAS-n, VAS-a), overall reoperation rates, complications, and rates of ASD. METHODS: A systematic search strategy of three electronic databases (PubMed, CINAHL Plus, and SCOPUS) was conducted utilizing terms related to two-level ACDR. All studies included had a sample size of >10 patients, had a minimum 5-year follow-up, and reported data on adjacent segment disease. Cadaver studies, non-English manuscripts, articles with less than 5-year follow-up and studies in which only single-level ACDR was investigated were excluded. A total of seven studies were included in this analysis. Studies were analyzed for demographic data, clinical outcome scores (NDI, VAS-neck, and VAS-arm), overall reoperation rates, complications, and rates of ASD. A random-effects model of meta-analysis was used for groups that were determined to be heterogenous and a fixed-effects model was utilized for groups that were not. An overlap of 95% confidence intervals suggests no statistically significant difference at the p<.05 level. RESULTS: Seven studies were included with data on 980 patients (442 MoM, 538 MoP). The study population was 52.84% female, with a mean age of 48.01 years, and a mean follow-up of 85.66 months. The mean improvement in NDI was 34.42 (95% CI, 32.49-36.36) and 29.72 (95% CI, 27.15-32.29) for the MoM and MoP groups, respectively. The mean improvement in VAS-neck was 11.20 (95% CI, 10.69-11.70) and 8.78 (95% CI, 7.81-9.74) for the MoM and MoP groups, respectively. The mean improvement in VAS-arm was 10.73 (95% CI, 9.83-11.63) and 8.49 (95% CI, 7.59-9.39) for the MoM and MoP groups, respectively. 3.85% (95% CI, 2.40-6.10) of patients who underwent ACDR with a MoM implant required reoperation compared to 5.33% (95% CI, 3.68-7.65) of patients with a MoP implant. Heterotopic ossification and dysphagia were the most common complications in both groups. The MoM cohort showed a higher incidence of HO (72.62% vs. 21.07%), but a lower incidence of dysphagia (0.96% vs. 16.31%) compared to the MoP cohort. The MoM cohort had a larger proportion of patients with ASD who underwent subsequent surgery at an adjacent level (7.89% MoM versus 1.91% MoP). CONCLUSIONS: Our present meta-analysis suggests that the use of MoM artificial discs in two-level ACDR results in superior clinical outcome score improvement, but higher rates of ASD requiring secondary surgery compared to MoP discs after a follow-up period of 5 years or more.

Does obesity affect long-term outcomes of extreme lateral interbody fusion with posterior stabilization?

BACKGROUND CONTEXT: Obese patients can pose significant challenges to spine surgeons in lumbar fusion procedures. The increased risk of complications has led surgeons to be wary in pursing operative interventions in these patients. Since the advent of minimally-invasive techniques in lumbar fusion, surgeons are turning to these procedures in an attempt to minimize operative time, blood loss and overall cost. With an increased proportion of obese patients in the population, it is imperative to understand the long-term outcomes in these minimally-invasive approaches. PURPOSE: The purpose of this study was to evaluate the long-term safety and efficacy of extreme lateral interbody fusion (XLIF) in the obese. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: A total of 115 patients (53 nonobese and 62 obese) who underwent XLIF with a minimum of 5-year follow-up. OUTCOME MEASURES: (1) Patient reported outcome scores: Visual Analog Scale (VAS) for back pain, Oswestry Disability Index (ODI), (2) Reoperation rate, (3) Pelvic incidence (PI)- Lumbar lordosis (LL) mismatch correction, (4) Graft subsidence and fusion rate METHODS: A retrospective review was performed to identify patients who underwent XLIF with percutaneous posterior stabilization since 2007 with a minimum follow-up of 5 years. Demographics including BMI were recorded and patients were subdivided into 2 cohorts: nonobese (BMI <30 kg/m2) and obese (BMI ≥30 kg/m2). Functional outcomes were assessed by comparing pre- and postoperative VAS and ODI scores. Reoperation rates were compared between cohorts. PI-LL mismatch was calculated from both pre- and postoperative radiographs. Rates of graft subsidence and fusion were measured at final follow-up. RESULTS: A total of 115 consecutive patients were included (53 nonobese and 62 obese) with a mean follow up of 95.3 months. Mean BMI was 25.3 in the nonobese group and 35.3 in the obese group (p<.001). There were more females in nonobese cohort. VAS scores decreased by a mean of 5.7 in the nonobese cohort, and 5.4 in the obese cohort (p=.213). ODI improvement was also similar between the groups. 5.6% of nonobese patients required reoperation compared to 9.6% of obese patients (p=.503). Graft subsidence rates at final follow-up were 5.66% and 8.06% for the nonobese and obese groups, respectively (p=.613). Rates of successful fusion were 96.23% and 98.39% for the nonobese and obese groups, respectively (p=.469). Both cohorts achieved a similar proportion of PI-LL mismatch correction, 85% in obese versus 78% in nonobese patients (p=.526). CONCLUSION: Obese patients have similar surgical outcomes to nonobese patients with respect to functional outcome scores, reoperation rates, graft subsidence and correction of PI-LL mismatch after long-term follow-up. With similar outcome and reoperation profiles, minimally-invasive approaches to the spine, such as XLIF, may be an acceptable alternative to traditional open procedures in obese patients.

Does Percutaneous Lumbosacral Pedicle Screw Instrumentation Prevent Long-Term Adjacent Segment Disease after Lumbar Fusion?

STUDY DESIGN: Retrospective cohort study. PURPOSE: To assess long-term clinical outcomes of adjacent segment disease (ASD) in patients who underwent lumbar interbody fusion with percutaneous pedicle screw (PS) instrumentation. OVERVIEW OF LITERATURE: ASD is a well-known sequela of spinal fusion, and is reported to occur at a rate of 2%-3% per year. There is debate as to whether ASD is a result of the instrumentation and fusion method or is the natural history of the patient's disease. Minimally invasive percutaneous PS augmentation of lumbar interbody fusion aims to prevent the disruption of posterior soft tissue stabilizers. METHODS: From 2004-2014, 419 consecutive patients underwent anterior, lateral, or minimally invasive transforaminal lumbar interbody fusion with percutaneous PS placement at a single institution. The mean follow-up was 4.5 years. The primary outcome measure was reoperation due to ASD. Patients were divided into two cohorts: those who underwent revision surgery secondary to ASD and those who did not require further surgery. Radiographic parameters were performed using postoperative radiographs. Patients with a pelvic incidence-lumbar lordosis (PI-LL) mismatch >10° were noted. RESULTS: Revision proportion secondary to ASD was 4.77% (n=20). Mean time to revision surgery was 2.5 years. Revision rate secondary to ASD was 1.1% per year. Patients who developed ASD were younger than those who did not (50.5 vs. 56.9 years, p=0.015). There was no difference in number of levels fused between cohorts. Revision proportion secondary to ASD was similar between approaches (anterior, lateral, minimally invasive). There was no significant difference in PI-LL mismatch between those who underwent revision for ASD and those who did not (22.2% vs. 18.8%, p=0.758). CONCLUSIONS: ASD rates in patients who underwent percutaneous PS placement were lower than those previously published after open PS placement, possibly related to greater preservation of the posterior stabilizing elements of the lumbar spine.

Cervical Computed Tomography Angiography Rarely Leads to Intervention in Patients With Cervical Spine Fractures.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To evaluate the impact of computed tomography angiography (CTA) in the management of trauma patients with cervical spine fractures by identifying high-risk patients for vertebral artery injury (VAI), and evaluating how frequently patients undergo subsequent surgical/procedural intervention as a result of these findings. METHODS: All trauma patients with cervical spine fractures who underwent CTA of the head and neck at our institution between January 2013 and October 2017 were identified. Patients were indicated for CTA according to our institutional protocol based on the modified Denver criteria, and included patients with cervical fractures on scout CT. Those with positive VAI were noted, along with their fracture location, and presence or absence of neurological deficit on physical examination. Statistical analysis was performed and odds ratios were calculated comparing the relationship of cervical spine fracture with presence of VAI. RESULTS: A total of 144 patients were included in our study. Of those, 25 patients (17.4%) were found to have VAI. Two patients (1.4%) with VAI underwent subsequent surgical/procedural intervention. Of the 25 cervical fractures with a VAI, 20 (80%), were found to involve the upper cervical region (4.2 OR, 95% CI 1.5-12.0; P = .007). Of the 25 who had a VAI, 9 were unable to undergo reliable neurologic examination. Of the remaining 16 patients, 5 (31.3%) had motor or sensory deficits localized to the side of the VAI, with no other attributable etiology. CONCLUSIONS: Cervical spine fractures located in the region of the C1-C3 vertebrae were more likely to have an associated VAI on CTA. VAI should also be considered in cervical trauma patients who present with neurological deficits not clearly explained by other pathology. Despite a finding of VAI, patients rarely underwent subsequent surgical or procedural intervention.

Primary Extramedullary, Extradural Cervical Spine Seminoma.

While extragonadal seminomas resulting in spinal cord compression are rarely reported in the literature, most have been treated with surgical decompression followed by radiation therapy. In this report, we present the unique and interesting case of a 38-year-old man who initially presented as an outpatient with a chief complaint of axial neck pain and lateral thoracic wall pain. After an extensive malignancy workup, he was diagnosed with a primary cervical spine seminoma and was treated with a C6-T1 laminectomy with posterior spinal instrumentation from C5 to T2. He has since undergone chemotherapy with cisplatin, vinblastine, and bleomycin, and at 24-month follow-up, he remains asymptomatic with no signs of recurrent disease.

Transsacral interbody fixation versus transforaminal lumbar interbody fusion at the lumbosacral junction for long fusions in primary adult scoliosis.

OBJECTIVE: Achieving fusion at the lumbosacral junction poses many technical challenges. No data exist in the literature comparing radiographic or clinical outcomes between the different surgical techniques of transsacral fixation (TSF) with rods and transforaminal lumbar interbody fusion (TLIF) in conjunction with iliac fixation. The purpose of this study was to compare the clinical outcomes and radiographic fusions of TSF to TLIF in patients with adult spinal deformity undergoing long fusions across the lumbosacral junction. METHODS: Patients with primary adult spinal deformity who underwent long fusions from the thoracic spine across the lumbosacral junction with different approaches of interbody fusion at the L5-S1 level were reviewed. Patients were subdivided by approach (TSF vs TLIF). Fusion status at L5-S1 was evaluated by multiple radiographs and/or CT scans. Scoliotic curve changes were also evaluated preoperatively and at final follow-up. Clinical outcomes were assessed by Scoliosis Research Society Outcome Instrument 22 and Oswestry Disability Index scores. RESULTS: A total of 36 patients were included in the analysis. There were 18 patients in the TSF group and 18 patients in the TLIF group. A mean of 14.00 levels were fused in the TSF group and 10.94 in the TLIF group (p = 0.01). Both groups demonstrated significant postoperative radiographic improvement in coronal parameters. The fusion rates for TSF and TLIF groups were 100% and 88.9%, respectively (p < 0.05). Eight patients in the TSF group had pelvic fixation with unilateral iliac screws, compared to 15 patients in the TLIF group (p = 0.015). No statistical differences in patients' reported outcomes were seen between groups. CONCLUSIONS: Despite similar clinical and radiographic outcomes between both groups, TSF required fewer iliac screws to augment stability of the lumbosacral junction while achieving a higher rate of fusion. This study suggests that TSF may decrease potential instrument-related complications requiring revision while decreasing operating room time and implant-related costs.

Thyrotoxic Periodic Paralysis: A Spine Consultation.

As a consultant, the orthopaedic spine surgeon is often asked to evaluate patients with acute-onset extremity weakness. In some cases, patient's deficits can be attributed to nonspinal pathology; therefore, it is important to be aware of nonorthopaedic diagnoses when evaluating these patients. We report a case of thyrotoxic periodic paralysis that was initially confused by the consulting service with spinal pathology. A 32-year-old Hispanic man presented to our emergency department with rapid onset of lower extremity weakness. The consulting team ordered CT of the cervical and lumbar spine, as well as MRI of the lumbar spine which was aborted due to the patient's worsening tachycardia and chest pain. The spine service was subsequently consulted to evaluate the patient. Review of the metabolic panel revealed a low potassium, and additional testing led to the eventual diagnosis of thyrotoxic periodic paralysis. After correction of the patient's potassium, his weakness rapidly resolved, and no additional spinal workup was pursued. We describe this patient's presentation and outline the differential diagnosis for acute, nontraumatic extremity weakness, including both orthopaedic and other medical causes, that the spine surgeon should be aware of when evaluating patients with extremity weakness.

Minimally Invasive Posterior Cervical Foraminotomy as an Alternative to Anterior Cervical Discectomy and Fusion for Unilateral Cervical Radiculopathy: A Systematic Review and Meta-analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: The aim of this study was to evaluate clinical outcomes, complications, and reoperations of minimally invasive posterior cervical foraminotomy (MI-PCF) for unilateral cervical radiculopathy without myelopathy, in comparison to anterior cervical decompression and fusion (ACDF). SUMMARY OF BACKGROUND DATA: ACDF is a standard treatment for cervical radiculopathy secondary to lateral disc herniation or foraminal stenosis. Recent studies have suggested MI-PCF to be an effective alternative to ACDF. However, concern for reoperation and whether similar improvements in clinical outcomes can be achieved has led to a debate in the literature. METHODS: We comprehensively searched PubMed, CINAHL Plus, and SCOPUS utilizing terms related to MI-PCF. Two independent reviewers assessed potential studies and extracted data on clinical outcome scores (neck disability index [NDI], visual analog scale [VAS]-neck, and VAS-arm), reoperation proportion, and complications. Studies included were on noncentral cervical pathology, published in the last 10 years, had a sample size of >10 patients, and reported data on minimally invasive techniques for posterior cervical foraminotomy. Heterogeneity and publication bias analyses were performed. The pooled proportions of each outcome were compared to those of ACDF obtained from two previously published studies. RESULTS: Fourteen studies were included with data of 1216 patients. The study population was 61.8% male, with a mean age of 51.57 years, and a mean follow-up of 30 months. MI-PCF resulted in a significantly greater improvement in VAS-arm scores compared to ACDF, and similar improvements in VAS-neck and NDI scores. Proportions of complications and reoperations were similar between the two cohorts. The most common complications were transient neuropraxia, wound-related, and durotomy. CONCLUSION: Our findings suggest that MI-PCF may be utilized as a safe and effective alternative to ACDF in patients with unilateral cervical radiculopathy without myelopathy, without concern for increased reoperations or complications. LEVEL OF EVIDENCE: 3.

Cervical Spinal Stenosis with Coexisting Rotator Cuff Tear: A Nationwide Review of Records from 2005 to 2014.

Rotator cuff tear (RCT) and cervical spinal stenosis (CSS) are common pathologies in the elderly. Both conditions may present with lateral shoulder pain and weakness or numbness of the upper extremity, potentially affecting patients' ability to live independently. Few data are available on the incidence of CSS among patients with concurrent RCT. The purpose of this study was to investigate the incidence of CSS among RCT patients, demographics, and surgical management using a national insurance database. The Medicare database was used to identify patients with RCT and concomitant CSS by ICD-9 codes from 2005-2014. Trends based on age, gender, and body mass index (BMI) were assessed. Utilization of open and arthroscopic rotator cuff repair (RCR) was compared. A total of 86,501 patients were identified. The number of patients diagnosed with RCT and CSS significantly increased (p< 0.0001). The incidence of CSS in patients with RCT increased from 9% to 13% (p < 0.05). Females < 64 years were more likely to exhibit combined pathology than age-matched males (OR 1.15, 95% CI 1.12 to 1.18) or females > 65 years (OR 1.64, 96% CI 1.61 to 1.67). A BMI of 30-40 kg/m2 demonstrated the highest incidence (43%, p < 0.0001). Arthroscopic RCR increased by 2% (p = 0.03) in RCT-CSS. The incidence of CSS in RCT patient is increasing. Orthopedic surgeons should maintain high clinical suspicion for concurrent CSS pathology in patients with RCT, particularly in obese female patients > 65 years with several medical comorbidities. Further investigation into the influence of these concurrent pathologies on patient outcomes is warranted.

Short-Segment Fixation With Percutaneous Pedicle Screws in the Treatment of Unstable Thoracolumbar Vertebral Body Fractures.

Clinical care of patients with unstable thoracolumbar vertebral body fractures may be challenging, especially in the setting of polytrauma patients who require other acute intervention. Compared with the traditional open approach, percutaneous short-segment fixation constructs place less surgical burden on patients regarding operative time and blood loss. Between 2008 and 2012, 32 patients with a mean age of 49 years (range, 19-80 years) underwent percutaneous short-segment fixation at the authors' institution and had a minimum of 6 months of complete clinical and radiographic follow-up. Load-sharing classification scores were determined. Outcomes evaluated included anterior body height, posterior body height, local kyphosis, regional kyphosis, thoracolumbar junctional kyphosis, mean operative time, and total blood loss. Standard binomial and categorical comparative analyses were performed. All load-sharing classification scores were 7 or less, and 11 of the 32 patients were polytrauma patients requiring surgery. No difference was seen between preoperative and late measurements of anterior body height, posterior body height, local kyphosis, regional kyphosis, or thoracolumbar junctional kyphosis. There were no complications, revisions, or anterior corpectomies. Only 2 patients (6%) underwent elective removal of hardware at 1 year. Mean operative time was 43 minutes (range, 33-56 minutes), and mean estimated blood loss was less than 50 mL. Percutaneous short-segment fixation prevented loss of vertebral body height and progression of kyphosis in the treatment of unstable thoracolumbar fractures with load-sharing classification scores of 7 or less. This study shows that these fractures with a load-sharing classification score of 6 and 7 may be stabilized using fewer screws than traditional methods in some patients and allow polytrauma patients to undergo other acute treatment. [Orthopedics. 2018; 41(6):e802-e806.].

Risk Factors for Pseudarthrosis in Minimally-Invasive Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective cohort study (level of evidence: 4). PURPOSE: To describe the potential comorbid, operative, and radiographic risk factors for the development of clinically-relevant pseudarthrosis following minimally-invasive transforaminal lumbar interbody fusion (MIS-TLIF). OVERVIEW OF LITERATURE: MIS-TLIF has shown long-term clinical outcomes with decreased perioperative morbidity and earlier return to work, similar to those of open TLIF. However, unsuccessful fusion still remains a concern. The impacts of various patient, operative, and radiographic risk factors have not been evaluated for their potential association with pseudarthrosis related to MIS-TLIF. METHODS: Between 2012 and 2015, 204 consecutive patients underwent one or two-level MIS-TLIF at St. Joseph's University Medical Center, Paterson, NJ, USA; they had a minimum of 1 year of follow-up. The patients were divided into two cohorts: those who developed clinically-relevant pseudarthrosis and those who did not. Clinically-relevant pseudarthrosis was determined by both evidence on computed tomography and presence of continued clinical symptoms at 1-year follow-up. RESULTS: Revision surgery was the only identified non-radiographic factor associated with pseudarthrosis. Disc angle had the highest (R 2=0.8), followed by anterior disc height (R 2=0.79). Although posterior disc height and the ratio of anterior to posterior disc height showed a marked relationship with the outcome, the R 2-values were <0.3, thus indicating a less-strong correlation. The overall pseudarthrosis rate was 8%. No statistically significant differences were identified between the two cohorts with respect to mean age, sex, medical comorbidities, smoking status, or number of levels fused. CONCLUSIONS: Clinically-relevant pseudarthrosis is not uncommon following MIS-TLIF. In the current study, undergoing revision surgery, disc angle, and anterior disc height were observed to be associated with clinically-relevant pseudarthrosis. This study demonstrated that the patient population may benefit from an alternate approach.