bluuebunny/crossref_metadata_2025 huggingface dataset:
National Database Research in Spine Surgery
Authors: Sebastian Arjun S.
Published: March 2018

Many of the studies in the spine surgical literature using national databases have been directed at examining adverse events, readmission rates, cost, and risk factors for poorer outcomes. Although such studies allow for assessment of large cohorts taken from multiple institutions, they are limited by data collection methods, short-term follow-up, and minimal assessment of functional outcomes. Furthermore, few studies are directed at producing actionable practice changes to improve patient care. Recent work aimed at producing databases with more relevance to spine surgery represent exciting developments to the rapidly growing field of health outcomes research.
Comparing Short-term Complications of Inpatient Versus Outpatient Single-level Anterior Cervical Discectomy and Fusion
Authors: Khanna Ryan , Kim Robert B. , Lam Sandi K. , Cybulski George R. , Smith Zachary A. , Dahdaleh Nader S.
Published: March 2018

Study Design:

Multicenter propensity score-adjusted retrospective cohort study.

Objective:

To determine baseline 30-day complication rates for anterior cervical discectomy and fusion (ACDF) and compare clinical complications for patients undergoing single-level ACDFs between inpatient and outpatient settings.

Summary of Background Data:

ACDF remains the most common procedure in the treatment of a variety of cervical disc pathologies, making it a focus of quality improvement initiatives. Outpatient single-level ACDFs are becoming more common and offer advantages including reducing nosocomial infections and costs, as well as improved patient satisfaction.

Materials and Methods:

The 2011–2013 NSQIP datasets were queried to identify all patients who underwent single-level ACDF procedures using current procedural terminology codes. Outpatient and inpatient cohorts were matched 1:1 using propensity score analysis to assess short-term outcomes. The outcomes assessed included 30-day medical and surgical complications, reoperation, readmission, and mortality.

Results:

In total, 6940 patients underwent a single-level ACDF with an overall complication rate of 4.2%. A total of 5162 patients (74.4%) had an inpatient hospital stay after surgery, whereas 1778 patients (25.6%) had outpatient surgery. After matching based on preoperative and operative characteristics to account for potential confounders, the overall complication rate was higher in the inpatient arm compared with the outpatient arm (2.5% vs. 1.2%; P=0.003). The 30-day readmission rate was also higher but not significant in the inpatient group than the outpatient group (2.2% vs. 1.8%; P=0.355). Mortality was the same with 0.1% in both groups (P=0.564).

Conclusions:

Patients undergoing outpatient single-level ACDF had a lower 30-day complication rates than those undergoing it in the inpatient setting. Outpatient surgery for single-level ACDF is safe and a favorable option for suitable patients.

Level of Evidence:

Level 3.
A Comparative Study of Anterior Decompression With Fusion and Posterior Decompression With Laminoplasty for the Treatment of Cervical Spondylotic Myelopathy Patients With Large Anterior Compression of the Spinal Cord
Authors: Hirai Takashi , Yoshii Toshitaka , Arai Yoshiyasu , Sakai Kenichiro , Torigoe Ichiro , Maehara Hidetsugu , Tomori Masaki , Taniyama Takashi , Sato Hirokazu , Okawa Atsushi
Published: March 2018

Study Design:

This is a retrospective observational single-center study.

Objectives:

To compare anterior decompression and fusion (ADF) and laminoplasty (LAMP) for the treatment of cervical spondylotic myelopathy (CSM) patients with large anterior compression in terms of clinical and radiologic outcomes.

Summary of Background Data:

We have reported that insufficient posterior decompression could be often seen after laminoplasty for CSM patients with preoperative anterior clearance of the spinal cord, defined as an interval <4 mm between the preoperative the modified K-line and anterior structure of the spinal canal at most compressive segment on sagittal T1-weighted magnetic resonance imaging. Here we conduct a study comparing ADF and LAMP for the treatment of CSM patients with such a risk factor.

Materials and Methods:

Of the 221 consecutive CSM patients treated with either ADF or LAMP between 2008 and 2012 at our hospital, 79 patients in whom the interval was <4 mm with age ranged from 50 to 79 years were enrolled. Patients with myelopathy caused by single-level disk herniation, tumor or ossification of posterior longitudinal ligament, or patients with a history of cervical spine injury were excluded. The Japanese Orthopedic Association (JOA) scoring system for cervical myelopathy, recovery rate of the JOA score at the time of 2 years after surgery were investigated as clinical outcomes to compare these 2 groups.

Results:

Demographics were almost similar between ADF and LAMP groups. The mean preoperative and postoperative JOA scores were 10.9 and 13.8 points for ADF group and 10.1 and 12.4 points for LAMP group, indicating that the recovery rate of JOA score was significantly greater in ADF group (49.6%) than that in LAMP group (38.2%; P=0.047). In LAMP group, spinal cord deformity was a significant predictive factor for unsatisfactory clinical outcome.

Conclusion:

ADF provided better surgical treatment for the patients with absence of preoperative anterior clearance of the spinal cord.
Semirigid Waved Rod System for the Treatment of the Degenerative Lumbar Diseases
Authors: Wang Lei , Lin Dasheng , Zou Weitao , Liu Hui , Lian Kejian
Published: March 2018

Background:

The semirigid pedicle screw instrumentation has gained wide popularity in recent decennium in lumbar fusion surgery. However, few data were documented to compare the clinical efficacy between semirigid and traditional rigid pedicle screw systems.

Materials and Methods:

A total of 96 patients with degenerative lumbar diseases were selected to perform operations between 2008 and 2013. The patients were prospectively randomized into 2 groups: 50 patients were managed by semirigid waved rod systems and 46 patients were intervened by traditional rigid straight stiff rod systems. X-rays and computed tomography were utilized to examine the interbody fusion status in the follow-up in detail. Surgical parameters such as operative time, blood loss, and total hospital stay were calculated and compared. Visual Analog Scale and Oswestry Disability Index were used to assess clinical efficacy postoperatively.

Results:

No significant differences were found about demographic data between groups. There were no significant differences regarding the surgical parameters including operative time, blood loss, and total hospital stay. Visual Analog Scale and Oswestry Disability Index postoperatively were also similar between the 2 instrumentations (P>0.05). The fusion rate was higher in the semirigid group (45/50) than in the traditional group (34/46) (P=0.039) at the final follow-up.

Conclusions:

Waved rod may be better in facilitating interbody fusion compared with traditional straight rod, although waved rod and straight stiff rod can both get similar clinical efficacy. Meanwhile, waved rod is likely superior in alleviating adjacent degeneration segments.
Novel Index to Quantify the Risk of Surgery in the Setting of Adult Spinal Deformity
Authors: Diebo Bassel G. , Jalai Cyrus M. , Challier Vincent , Marascalchi Bryan J. , Horn Samantha R. , Poorman Gregory W. , Bono Olivia J. , Cherkalin Denis , Worley Nancy , Oh Jason , Naziri Qais , Spitzer Allison , Radcliff Kris , Patel Ashish , Lafage Virginie , Paulino Carl B. , Passias Peter G.
Published: March 2018

Study Design:

Retrospective review of the Nationwide Inpatient Sample from 2001 to 2010, a prospectively collected national database.

Objective:

Structure an index to quantify adult spinal deformity (ASD) surgical risk based on risk factors for medical complications, surgical complications, revisions (R), mortality (M) rates, and length of hospital stay.

Summary of Background Data:

Evidence supporting ASD surgery cost-effectiveness and anticipating surgical risk is critical to evaluate the risk/benefit balance of such treatment for patients.

Materials and Methods:

Discharges ages 25+, 4+ levels fused, diagnoses specific for scoliosis, and refusions. Five multivariate models determined independent risk factors that increased the risk of ≥1 for medical complications, surgical complications, R, M, and length of hospital stay. Models controlled for age, sex, race, revision status, surgical approach, levels fused, and osteotomy utilization. Odds ratios (ORs) were weighted using Nationwide Inpatient Sample weight files and based on their predictive category: 2 times for revision predictors and 4 times for mortality predictors. Predictors with OR≥1.5 were considered clinically relevant. Fifty points were distributed among the predictors based on their accumulative OR to establish a risk index.

Results:

A total of 10,912 ASD discharges were identified (mean age: 62 y; 73% females; 14% revision cases). The structured risk index incorporated the following factors based on accumulative ORs: pulmonary circulation disorder (42.05), drug abuse (21.86), congestive heart failure (15.25), neurological disorder (17.31), alcohol abuse (13.24), renal failure (11.64), age>65 (12.28), coagulopathy (11.65), level +9 (6.7), revision (3.35), and osteotomy (3). These risk factors were scored: 14, 7, 5, 5, 4, 4, 4, 4, 2, 1, 1, respectively. Three risk thresholds were proposed: mild (0–10), moderate (10–20), severe >20/50 points.

Conclusions:

This study proposes an index to quantify the possible risk of morbidity before ASD surgery that will help patients, health insurance companies, and socioeconomic studies in assessing surgical risk/benefits.

Level of Evidence:

Level III.
Nerve Root and Lumbar Plexus Proximity to Different Extraforaminal Lumbar Interbody Fusion Trajectories
Authors: Kumar Abhishek , Merrill Robert K. , Qureshi Sheeraz A.
Published: March 2018

Study Design:

Cadaver study.

Objective:

To investigate the safety of the extraforaminal lumbar interbody fusion approach.

Summary of Background Data:

Over the last decade the number of techniques available for lumbar interbody fusion has increased. Recent interest has developed in an extraforaminal approach to the intervertebral disc to reduce the morbidity associated with facetectomy. The safety of this extraforaminal corridor with regards to the exiting nerve root and lumbar plexus has yet to be assessed.

Methods:

With the cadaver prone, the C-arm was positioned over the disc of interest and aligned perpendicular to the superior endplate of the inferior vertebral body, with the superior articular process bisecting the available disc space. Three needles were passed into the disc and labeled medial, middle, and lateral. After needle placement, each nerve root and the lumbar plexus were dissected. The distance of each needle to these structures was measured and discectomy was performed to assess potential graft length from a transforaminal and extraforaminal approach.

Results:

We performed the method on levels L1–L5 bilaterally on 2 cadavers, totaling 16 attempts for each needle position. The average distance to nerve of the medial approach (3.2±1.1 mm) was statistically greater than both the middle (1.1±1.4 mm) and lateral (−0.2±2.9 mm) approaches (P<0.0001 for both). The distance to plexus of the medial approach (14.3±6.2 mm) was greater than the middle (9.2±6.1 mm) approach and statistically greater than the lateral (5.2±5.6 mm) approach (P=0.001). There was a greater graft length available by the extraforaminal lumbar interbody fusion approach (36.1±2.7 mm) than the transforaminal lumbar interbody fusion approach (29.3±3.5 mm, P<0.0001).

Conclusions:

The safest trajectory was the medial, passing adjacent to the superior articular process. The close proximity, however, means that neuromonitoring and tubular dilators would be necessary to use this technique in a clinical setting.

Level:

Level V.
The Evolution of Current Research Impact Metrics
Authors: Butler Joseph S. , Kaye I. David , Sebastian Arjun S. , Wagner Scott C. , Morrissey Patrick B. , Schroeder Gregory D. , Kepler Christopher K. , Vaccaro Alexander R.
Published: March 2018

The prestige of publication has been based on traditional citation metrics, most commonly journal impact factor. However, the Internet has radically changed the speed, flow, and sharing of medical information. Furthermore, the explosion of social media, along with development of popular professional and scientific websites and blogs, has led to the need for alternative metrics, known as altmetrics, to quantify the wider impact of research. We explore the evolution of current research impact metrics and examine the evolving role of altmetrics in measuring the wider impact of research. We suggest that altmetrics used in research evaluation should be part of an informed peer-review process such as traditional metrics. Moreover, results based on altmetrics must not lead to direct decision making about research, but instead, should be used to assist experts in making decisions. Finally, traditional and alternative metrics should complement, not replace, each other in the peer-review process.
Perioperative Management of Blood Loss in Spine Surgery
Authors: Qureshi Rabia , Puvanesarajah Varun , Jain Amit , Hassanzadeh Hamid
Published: March 2018

Spine procedures are associated with high rates of blood loss which can result in a greater need for transfusions. Repeated exposure to blood products is associated with risks and adverse reactions such as transfusion-related acute lung injury, fluid shifting, and infections. With the higher number of spine procedures and the increasing open surgery times associated with difficult procedures, excessive blood loss has become more prevalent. Perioperative methods have been established to combat the excessive blood loss and decrease the need for blood products. Preoperatively, anemia and coagulopathy screening is standard at least 4 weeks before elective procedures. Erythropoietin, iron loading or transfusions are used to decrease preoperative anemia, a predisposing factor for blood loss. Autologous predonation of blood has been shown to be ineffective and decreases preoperative hemoglobin levels. Intraoperatively, antifibrinolytics such as tranexamic acid and aminocaproic acid are used to decrease blood loss. In addition, fibrinogen concentrates, thromboelastometry, acute normovolemic hemodilution, controlled hypotension, and temperature regulation are some of the techniques used to decrease blood loss and the need for transfusions. Postoperatively, fibrin sealants, shed blood salvage, and erythropoietin or intravenous iron are used in management of blood loss, especially in instances when the patient refuses blood products.
Payor Reform Opportunities for Spine Surgery
Authors: Scalise Jason , Jacofsky David
Published: March 2018

Spine surgery, and orthopedic surgery overall, is being increasingly scrutinized by payors due to large projected increases in utilization. The unsustainability of the fee-for-service payment system has lead payors to investigate novel value and risk-based contracting strategies on an episode of care basis and on a population health basis. These forays into progressive models for spine surgery have been supported by the successes demonstrated by advanced payor reform programs from The Centers for Medicare and Medicaid Services in other areas of musculoskeletal medicine. Whether they are focused on lower extremity arthroplasty or spinal surgery, these pressures are forcing hospitals and physicians to align to improve quality and reduce costs through new structures and relationships. However, in many respects spine surgery has been years behind the wave of market pressures seen in other orthopedic subspecialties, such as arthroplasty. As such, the recognition and understanding of the forces and motivations driving the massive pressures responsible for these will better equip the spine surgeon to adapt and ultimately master such transformations.
Payor Reform Opportunities for Spine Surgery
Authors: Scalise Jason , Jacofsky David
Published: March 2018

As the cost of health care continues to rise, government and commercial payors are implementing strategies as a means of reducing the overall expenditure of health care dollars. The largest savings will be not just in more cost-effective treatments but in strategies that can avoid the need for treatments in the first place. Although the savings from popular payor reform strategies like bundled payments are tied to the initiation of the clinical episode, population health programs utilize a variety of tactics to decrease the need for health care utilization overall. However, the payor reform landscape is seeing some convergence of strategies as varying tactics can be complimentary. Given the dramatic rise in expenditures on spine surgery and related services, spine surgeons should understand how population health and other efforts will inevitably influence spine health care delivery going forward.
Interventional Approaches to Low Back Pain
Authors: Nelson Ariana M. , Nagpal Geeta
Published: March 2018

Chronic low back pain (LBP) places a tremendous economic burden on society due to both direct and indirect costs. Health care costs for adults with chronic LBP have steadily increased over the past 20 years, coinciding with a large increase in the utilization of spinal injections, surgical interventions, opioid medications, and physical therapy. The treatment of LBP is best approached by a multimodal and even multidisciplinary approach with a combination of physical rehabilitation, pharmacologic management, psychological intervention, spinal injections, and surgical intervention with a goal of improving the functional status of the patient. In this review, we discuss the interventional management of LBP secondary to herniated nucleus pulposus, spinal stenosis, facet mediated pain, sacroiliitis, and discogenic pain.
Risk Factors Associated With Failure to Reach Minimal Clinically Important Difference in Patient-reported Outcomes Following Minimally Invasive Transforaminal Lumbar Interbody Fusion for Spondylolisthesis
Authors: Hijji Fady Y. , Narain Ankur S. , Bohl Daniel D. , Yom Kelly H. , Kudaravalli Krishna T. , Lopez Gregory D. , Singh Kern
Published: March 2018

Study Design:

Retrospective cohort.

Objective:

To determine risk factors associated with failure to reach the minimal clinically important difference (MCID) in patient-reported outcomes (PROs) for patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) for spondylolisthesis.

Summary of Background Data:

The MCID of PROs are often utilized to determine the benefit of spinal procedures. However, negative predictive factors for reaching MCID in patients surgically treated for lumbar spondylolisthesis have been difficult to elucidate.

Materials and Methods:

A prospectively maintained surgical database of patients who were diagnosed with lumbar spondylolisthesis and surgically treated with a single level MIS TLIF from 2010 to 2016 was reviewed. Patients with incomplete PRO survey data or <6-month follow-up were excluded from the analysis. MCID for visual analogue scale (VAS) back, VAS leg, and Oswestry Disability Index (ODI) was obtained from established values in the literature. All risk factors were then assessed for association with failure to reach MCID using bivariate and multivariate regression adjusting for preoperative characteristics.

Results:

A total of 165, 76, and 73 patients treated with MIS TLIF for spondylolisthesis had complete PRO data for VAS back, VAS leg, and ODI, respectively, and were thus included in the analysis for the respective PRO. Overall, 75.76%, 71.05%, and 61.64% of patients treated with a single level MIS TLIF for spondylolisthesis reached MCID for VAS back, VAS leg, and ODI, respectively. On multivariate analysis, patients were less likely to achieve MCID for VAS back following surgical treatment if they received workers’ compensation (P<0.001). No other measured factors were noted to independently correlate with MCID achievement.

Conclusions:

The results of this study suggest that a majority of patients with spondylolisthesis achieve MCID for commonly measured PROs following MIS TLIF for spondylolisthesis. However, worker’s compensation insurance status may serve as a negative predictive factor for reaching MCID.
Preoperative Opioid Use
Authors: Faour Mhamad , Anderson Joshua T. , Haas Arnold R. , Percy Rick , Woods Stephen T. , Ahn Uri M. , Ahn Nicholas U.
Published: March 2018

Study Design:

Retrospective comparative case-control study.

Objectives:

The objectives of this study are: (1) How preoperative opioid use impacts RTW status after single-level cervical fusion for radiculopathy? and (2) What are other postsurgical outcomes affected by preoperative opioid use?

Summary of Background Data:

Opioid use has increased significantly in the past decade. The use of opioids has a drastic impact on workers’ compensation population, an at-risk cohort for poorer surgical and functional outcomes than the general population.

Methods and Materials:

Data was retrospectively collected from Ohio Bureau of Workers’ Compensation between 1993 and 2011. The study population included patients who underwent single-level cervical fusion for radiculopathy as identified by current procedural terminology codes and International Classification of Diseases-9 codes. On the basis of opioid use before surgery, two groups were constructed (opioids vs. non-opioids). Using a multivariate logistic regression model, the effect of preoperative opioid use on return to work (RTW) status after fusion was analyzed and compared between the groups.

Results:

In the regression model, preoperative opioid use was a negative predictor of RTW status within 3-year follow-up after surgery. Opioid patients were less likely to have stable RTW status [odds ratio (OR), 0.50; 95% confidence interval (CI), 0.38-0.65; P=0.05] and were less likely to RTW within the first year after surgery (OR, 0.50; 95% CI, 0.37-0.66; P=0.05) compared with controls. Stable RTW was achieved in 43.3% of the opioids group and 66.6% of control group (P=0.05). RTW rate within the first year after fusion was 32.5% of opioids group and 57% of control group (P<0.05).

Reoperation and permanent disability rates after surgery were higher in the opioid group compared with the control group (P<0.05).

Conclusions:

In a workers’ compensation, patients with work-related injury who underwent single-level cervical fusion for radiculopathy and received opioids before surgery had worse RTW status, a higher reoperation rate, and higher rate of awarded permanent disability after surgery.
Is Body Mass Index a Risk Factor for Revision Procedures After Minimally Invasive Transforaminal Lumbar Interbody Fusion?
Authors: Narain Ankur S. , Hijji Fady Y. , Bohl Daniel D. , Yom Kelly H. , Kudaravalli Krishna T. , Singh Kern
Published: March 2018

Study Design:

Retrospective cohort study.

Objective:

To determine if an association exists between body mass index (BMI) and the rate of revision surgery after single-level minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

Summary of Background Data:

MIS TLIF is an effective treatment for lumbar degenerative disease. Previous studies in the orthopedic literature have associated increased BMI with increased postoperative complications and need for revision. Few studies have evaluated the association between BMI and the risk for revision after minimally invasive spinal procedures.

Materials and Methods:

A surgical registry of patients who underwent a single-level MIS TLIF for degenerative pathology between 2005 and 2014 was reviewed. Patients were stratified based on BMI category: normal weight (BMI<25), overweight (BMI, 25–29.9), obese I (BMI, 30–34.9), and obese II–III (BMI≥35). BMI category was tested for association with demographic and procedural characteristics using 1-way analysis of variance (ANOVA) for continuous variables, and χ2 analysis or the Fisher exact test for categorical variables. BMI category was tested for association with undergoing a revision fusion procedure within 2 years after MIS TLIF using multivariate Cox proportional hazards survival analysis modeling.

Results:

In total, 274 patients were analyzed; of these, 52 (18.98%) were normal weight, 101 (36.86%) were overweight, 62 (22.63%) were obese I, and 59 (21.53%) were obese II–III. On multivariate Cox proportional hazards survival analysis modeling, BMI category was not associated with undergoing a revision procedure within 2 years after MIS TLIF (P=0.599). On multivariate analysis, younger age (P=0.004) was associated with increased risk of undergoing a revision after MIS TLIF.

Conclusions:

The results of this study suggest that increasing BMI is not a risk factor for undergoing a revision procedure after MIS TLIF. As such, patients with high BMI should be counseled regarding having similar rates of needing a revision procedure after MIS TLIF as those with lower BMI.

Level of Evidence:

Level IV.
Differences in Fundamental Sagittal Pelvic Parameters Based on Age, Sex, and Race
Authors: Merrill Robert K. , Kim Jun S. , Leven Dante M. , Kim Joung Heon , Meaike Joshua J. , Bronheim Rachel S. , Suchman Kelly I. , Nowacki Doug , Gidumal Sunder S. , Cho Samuel K.
Published: March 2018

Study Design:

This is a retrospective cohort study.

Objective:

To determine whether age, sex, and race have independent effects on sagittal pelvic parameters.

Summary of Background Data:

Pelvic parameters and sagittal balance correlate with health-related quality of life and are important for patient assessment and surgical planning. Age, sex, and race are 3 unalterable patient factors that may influence pelvic morphology.

Methods:

We conducted a retrospective review of consecutive adult patients who presented to our radiology practice between 2010 and 2015 and had a standing, lateral lumbosacral radiograph. Any patients without both femoral heads and L1–S1 visible on the radiograph, and any patients presenting with traumatic injury, coronal deformity, prior instrumentation, spondylolisthesis, or neoplasm of the spine were excluded. Univariate analysis determined differences in measurements among African American, white, and Hispanic races, as well as between male and female sexes. Correlation analysis between age and different measurements was also conducted. Multivariable regression was then used to determine the independent effect of age, sex, and race on pelvic parameters.

Results:

We investigated 1801 adults (older than 18 y) and 1246 had a recorded race. There were 1165 women, 636 men, 525 whites, 404 African Americans, and 317 Hispanics. Multivariable regression demonstrated a statistically significant increase in pelvic tilt (PT), pelvic incidence (PI), and pelvic incidence-lumbar lordosis (PI-LL) with aging, and statistically significant decrease in sacral slope (SS) and LL with aging. Women had a statistically greater LL than men. African Americans had a statistically smaller PT and greater SS and PI-LL relative to whites, while Hispanics had a statistically smaller PT and PI-LL, and a statistically greater SS and LL relative to whites.

Conclusions:

Pelvic parameters were different between sexes, among races, and changed with age. These findings are important for patient assessment and preoperative planning to obtain optimal sagittal balance.

Level of Evidence:

Level 3.
Subsidizing the Sick
Authors: DiGiorgio Anthony M. , Mummaneni Praveen V. , Virk Michael S. , Sharan Alok D.
Published: March 2018

Insurance premium rates have typically been calculated using a variety of rating algorithms. Passage of the Patient Protection and Affordable Care Act mandated that all individual and small group plans must use the community rating method. This method gives the same insurance rate to all members of a community, with adjustments only being allowed based on age, geography, and tobacco use. This effectively raises rates on low-risk individuals to subsidize high-risk individuals. With President Trump and Congressional Republicans vowing to repeal the Patient Protection and Affordable Care Act, this lesser-known but controversial portion of the law may be abolished. This paper will review the various rating methods used by insurance companies in determining premiums.
Downward Laminotomy Technique for Hidden Zone Foraminal Disk Herniations
Authors: Naderi Sait , Onen Mehmet R.
Published: March 2018

Introduction:

Hidden zone foraminal herniations are among the more rare forms of herniations. As exploration is difficult, and there is a close relationship between the nerve root and pedicle, many surgical approaches have been proposed. The aim of this study was to describe downward laminotomy as a new approach to these herniations.

Materials and Methods:

A downward laminotomy technique was used in 5 cases with hidden zone foraminal disk herniation with no extension to the intervertebral disk space.

Results:

The herniated disk fragment was located at L4–L5 in 4 cases and at L3–L4 in 1 case. Mean visual analog scale scores reduced from preoperative 8.2 to 2.1 postoperatively. The allodynia was resolved in two months.

Conclusions:

It was concluded that downward laminotomy provides a safe, less risky, and minimally invasive approach to hidden zone foraminal disk herniations.
Microscope and Fiberscope-assisted Subarachnoid-Subarachnoid (S-S) Bypass
Authors: Fujiwara Yasushi , Manabe Hideki , Izumi Bunichiro , Shima Takayuki , Adachi Nobuo
Published: March 2018

A “dorsal spinal arachnoid web” is the thickened arachnoid band on the surface of the spinal cord which disturbs the cerebrospinal fluid (CSF) flow, known as a rare cause of thoracic myelopathy. The ideal treatment is controversial because of the risk of readhesion after simple resection of the web. A subarachnoid-subarachnoid bypass is a method to reestablish CSF flow through a silicon tube between the cranial and caudal subarachnoid space. This method is reported to be useful for traumatic syringomyelia, adhesive arachnoiditis, etc. We applied this technique for arachnoid webs with the assistance of a microscope and fiberscope. After a dura incision, the thickened arachnoid web can be seen fluttering within the CSF flow inside the arachnoid space, which partitions the subarachnoid space into cranial and caudal parts. After opening the subarachnoid space and resection of the web under a microscope, the fiberscope is inserted toward the cranial and caudal directions to check for the presence of another arachnoid web. If another web is found, it is penetrated using a guiding wire. Then, a silicone tube is inserted into the cranial and caudal normal subarachnoid space. In this paper, we would like to introduce this technique.
Spine Registries
Authors: Kaye Ian D. , Butler Joseph S. , Morrissey Patrick B. , Sebastian Arjun S. , Wagner Scott C. , Vaccaro Alexander R.
Published: March 2018

To curb the unsustainable rise in health care costs, novel payment models are being explored which focus on value rather than volume. Underlying this reform is an accurate understanding of costs and outcomes. The Patient Protection and Affordable Care Act, the Institute of Medicine, and the Agency for Healthcare Research and Quality have specifically advocated for the use of registries to help define the real-world effectiveness of surgical interventions to help guide health care reform. Registries can help define value by documenting surgical efficacy, and specifically by reporting patient-based outcome measures. Over the past 10 years, several spine registries have been initiated and some others have expanded. These are providing a repository of evidence for surgical value. Herein, we will review the components of a well-designed registry and provide examples of such registries and their impact on health care delivery.
Lateral Atlantoaxial Osteoarthritis
Authors: Buraimoh Morenikeji A. , Massie Lara W. , Montgomery David M.
Published: March 2018

Lateral atlantoaxial osteoarthritis (AAOA), or C1-C2 lateral mass arthritis (LMA), is an unfamiliar degenerative cervical disease with a clinical presentation that markedly differs from subaxial spondylosis. The prevalence of LMA in the nonsurgical outpatient setting is 4%. Risk factors include age and occupation. The typical patient is between 50 and 90 years old, presents with upper cervical or occipital pain, has limited rotation, and has pain provocation during passive rotation to the affected side. Pain stems from degeneration of the lateral C1-C2 articulation and may be referred or radicular, through the greater occipital nerve. Although there is no consensus on diagnostic work-up, the disease is classically seen on the open-mouth odontoid radiograph. Computerized tomography, magnetic resonance imaging, bone scan, and diagnostic injections are also useful. Initial treatment is conservative, and upwards of two-thirds of LMA patients obtain lasting relief with noninvasive measures and injections. In patients with severe, recalcitrant pain, limited C1-C2 fusion offers satisfactory and reliable relief. The goals of this review article are to provide a synthesis of the literature on LMA, to offer a treatment approach to LMA, and to identify problems with the current state of knowledge on LMA.
Modified Lumbosacral Angle and Modified Pelvic Incidence as New Parameters for Management of Pediatric High-grade Spondylolisthesis
Authors: Ma Zhenjiang , Zhao Changqing , Zhang Kai , Du Lin , Tian Jianping , Sun Xiaojiang , Zhao Jie
Published: March 2018

Study Design:

Retrospective clinical study.

Objective:

We aimed to introduce new parameters that can better describe the pelvic morphology and lumbosacral segmental deformity in children with high-grade spondylolisthesis of the L5 vertebra: modified pelvic incidence (mPI) and modified lumbosacral angle (mLSA). Also, we aimed to establish the mLSA as a convenient, reliable measurement method and criteria to evaluate the reduction of L5 vertebral slippage.

Summary of Background Data:

Numerous parameters and methods exist to evaluate segmental deformity and reduction of L5 vertebral slippage, but no definitive standard for accurately and conveniently describing lumbosacral kyphosis and degree of reduction exists.

Methods:

A total of 24 children with high-grade spondylolisthesis (S group) and 152 children without spondylolisthesis (non-S group) underwent standard lateral radiography of the spine in our hospital between June 2009 and June 2014. We compared mPI and mLSA between the S and non-S groups. The agreement and repeatability of mPI and mLSA were also assessed. Preoperative and postoperative Japanese Orthopaedic Association (JOA) and Scoliosis Research Society (SRS)-22 scores were compared to assess clinical outcomes in the S group. The correlations between modified parameter applications and clinical outcomes were also assessed.

Results:

While mPI did not differ between groups, mLSA differed significantly. In the non-S group, mLSA was lordotic (25.51±6.41 degrees). In the S group, mLSA was kyphotic (25.85±5.17 degrees) before surgery and lordotic (20.74±7.04 degrees) postoperatively. The agreement and repeatability of mPI and mLSA were good, and clinical outcomes of the S group were satisfactory. Positive correlations were found between modified parameter applications and the improvement rates of JOA scores.

Conclusions:

mPI and mLSA can better describe the pelvic morphology and local deformity of pediatric high-grade L5 spondylolisthesis, and mLSA can serve as a useful index for correcting lumbosacral kyphosis, rebalancing the sagittal spinal profile and predicting clinical outcomes.
Vertebroplasty and Kyphoplasty for Metastatic Spinal Lesions
Authors: Sadeghi-Naini Mohsen , Aarabi Shahram , Shokraneh Farhad , Janani Leila , Vaccaro Alexander R. , Rahimi-Movaghar Vafa
Published: March 2018

Introduction:

The spine is the most common site of bone metastases. Vertebroplasty (VP) and kyphoplasty (KP) have been proposed as potential minimally invasive therapeutic options for metastatic spinal lesion (MSL) pain. However, the efficacy of VP and KP on MSL pain is currently unclear.

Objective:

The aim of this study was to assess the effects of VP and KP compared with each other, usual care, or other treatments on pain, disability, and quality of life following MSL.

Methods:

We included randomized controlled trials and prospective nonrandomized controlled clinical trials assessing VP or KP for the treatment of pain following MSL without cord compression. We searched MEDLINE, EMBASE, PubMed, and CENTRAL.

Results:

The literature search revealed 387 citations. Of these, 9 trials met all eligibility criteria and were included in the qualitative analysis. In total, there were 622 patients enrolled in the trials and of them 432 were in the surgical treatment group (92 received KP, 97 received VP, 134 received VP and chemotherapy, 68 received VP and radiotherapy, and 41 received Kiva implant) and 190 were in the nonsurgical treatment group (83 received chemotherapy, 46 received radiotherapy, and 61 received other treatment). Using the grading of recommendations assessment, development and evaluation approach, pain (low-quality evidence) and functional scores (very low-quality evidence) improved more with VP plus chemotherapy than with chemotherapy alone (pain: mean difference, −3.01; 95% confidence interval, −3.21 to −2.80; functional score: mean difference, 15.46; 95% confidence interval, 13.58–17.34). KP seemed to lead to significantly greater improvement in pain, disability, and health-related quality of life (HRQoL) compared with nonsurgical management. VP plus Iodine-125 seemed to lead to significantly greater improvement in pain and disability in comparison with VP alone. VP plus radiochemotherapy resulted in better pain relief and HRQoL postoperatively in comparison with routine radiochemotherapy. There was low-quality evidence to prove that surgical treatment significantly decreases pain, and improves functional score and HRQoL following MSL in comparison with nonsurgical management.

Conclusion:

On the basis of the analysis of currently published trial data, it is unclear whether VP for MSL provides benefits over KP.

Level of Evidence:

Level 2.
Minimally Invasive Spine Surgery
Authors: Bryant Jessica , Mohan Rohith , Koottappillil Brian , Wong Kevin , Yi Paul H.
Published: March 2018

Study Design:

This is a cross-sectional study.

Objective:

The purpose of this study is to evaluate the content of information available on the Internet regarding minimally invasive spine surgery (MISS).

Summary of Background Data:

Patients look to the Internet for quick and accessible information on orthopedic procedures to help guide their personal decision making process regarding the care they receive. However, the quality of internet-based orthopedic education material varies significantly with respect to accuracy and readability.

Materials and Methods:

The top 50 results were generated from each of 3 search engines (Google, Yahoo!, and Bing) using the search term “minimally invasive spine surgery.” Results were categorized by authorship type and evaluated for their description of key factors such as procedural benefits, risks, and techniques. Comparisons between search engines and between authorship types were done using the Freeman-Halton extension for the Fisher exact test. The content of websites certified by Health on the Net Foundation (HONcode) was compared with those not HONcode certified.

Results:

Of the 150 websites and videos, only 26% were authored by a hospital or university, whereas 50% were by a private physician or clinic. Most resources presented some benefits of MISS (84%, 126/150), but only 17% presented risks of the procedure (26/150). Almost half of all resources described the technique of MISS, but only 27% had thorough descriptions that included visual representations while 26% failed to describe the procedure. Only 12 results were HONcode certified, and 10 (83%) of these were authored by a medical industry company.

Conclusions:

Internet-based resources on MISS provide inconsistent content and tend to emphasize benefits of MISS over risks.
Co-management Strategies for Hospitals and Orthopedic and Neurosurgery Practices
Authors: Tromanhauser Scott G.
Published: March 2018

Co-management arrangements can be a very effective means of aligning physicians and their hospitals to gain care delivery efficiencies, control costs, and reduce variation in practices. In an era of value-based care delivery all aspects must be examined and the appropriate incentives put in place to reduce waste and optimize asset and resource utilization. This article will review legal considerations, define basic co-management structure and goals, and suggest examples of metrics used to achieve success.
Characteristics of Cervical Spine Motion in Different Types of Cervical Alignment
Authors: Sessumpun Kittipong , Paholpak Permsak , Hindoyan Kevork N. , Tamai Koji , Sangkomkamhang Thananit , Buser Zorica , Wang Jeffrey C.
Published: March 2018

Study Design:

Retrospective study.

Objective:

To evaluate how each type of sagittal cervical alignment affects the motion of the upper and subaxial cervical spine using kinematic magnetic resonance imaging.

Summary of Background Data:

The sagittal malalignment of the cervical spine from degeneration in the subaxial cervical spine reflects a disruption in the kinematic properties of the cervical spine and affects the motion of adjacent segments. Changes in the sagittal parameters and kinematics of the upper cervical spine and upper thoracic spine due to the kyphosis are unknown.

Methods:

Kinematic magnetic resonance imaging of the cervical spine in neutral position from 311 patients, including 90 lordotic, 90 straight, 90 global kyphotic, and 41 segmental kyphotic were analyzed. The lordotic angle at the upper and lower cervical spine, and T1 slope were measured in the neutral position and again in flexion and extension for dynamic analysis.

Results:

The number of levels with significant disk degeneration was higher in the global kyphosis group. In the global kyphosis group, neutral sagittal parameters showed some characteristics of compensation to the malalignment. Compared with the lordotic group, patients with global kyphosis demonstrated significantly higher lordotic angle of the upper cervical spine and more horizontal T1 slope. The dynamic evaluation showed greater range of motion of the entire cervical spine and subaxial cervical spine in younger patients. However, we still found greater range of motion of the occipito-atlanto-axial complex in global kyphosis, even when controlling for age and number of levels with significant disk degeneration.

Conclusion:

Sagittal malalignment of the cervical spine affects all parts of the cervical motion complex. The global kyphotic alignment of subaxial cervical spine affects the kinematic properties of the occipito-atlanto-axial complex and upper thoracic spine to compensate for the alteration of cervical alignment. These differences are not seen in straight and segmental kyphosis.

Level of Evidence:

Level 3.
Disparities and the American Health Care System
Authors: Amin Sheena A. , McEntee Richard M. , Wagner Scott C. , Schroeder Gregory D. , Knightly John J. , Vaccaro Alexander R.
Published: March 2018

The United States’ health care system is often compared with those of other industrialized countries, and consistently ranks poorly in terms of health care delivery, efficiency, and quality. However, there are several considerations unique to the United States that are often distorted in these analyses, and when considered in the context of the convoluted ethnic and social disparities that persist in the United States, the successes of the American health care system become more apparent.
One-step Minimally Invasive Pedicle Screw Instrumentation Using O-Arm and Stealth Navigation
Authors: Kleck Christopher J. , Johnson Christopher , Akiyama Michelle , Burger Evalina L. , Cain Christopher J. , Patel Vikas V.
Published: March 2018

Study Design:

Description of a navigated, single-step, minimally invasive technique for the placement of pedicle screws.

Objective:

To describe a new technique for minimally invasive placement of pedicle screws in the lumbar spine using O-arm and StealthStation navigation in combination.

Summary of Background Data:

Minimally invasive surgical techniques are described in the literature as safe and effective methods for pedicle screw instrumentation. These techniques increase radiation exposure and prompt multiple instrument passes through the pedicle.

Materials and Methods:

In total, 35 adult patients (187 screws) underwent lumbar surgery with pedicle screw placement using the 1- (8 patients/48 screws) or 2-step (27 patients/139 screws) technique. Complications associated with instrumentation were noted. Pedicle screw position was evaluated.

Results:

Of 187 screws placed, 181 (96.8%) were found to be fully contained within the pedicle (grade 1) and 4 (2.1%) had a breach of <2 mm. In the 1-step technique, no screws were malpositioned. One screw at S1 with inadequate fixation was replaced with a screw 1 mm larger in diameter. In the 2-step technique, 2 screws (1.06% overall) were revised due to inferior breach of the pedicle. No neurological sequelae were noted. Also, 1 screw was deemed too long at S1 and was replaced with a shorter screw. None of the revised pedicle screws caused neuromonitoring changes and the breaches were found intraoperatively on 3D imaging.

Conclusions:

Using O-arm and StealthStation navigation with minimally invasive surgical technology for placement of posterior spinal instrumentation is safe, effective, and limits radiation exposure.
Validity and Reproducibility of Various Measurement Methods for Craniocervical Sagittal Balance
Authors: Tamai Koji , Suzuki Akinobu , Takahashi Shinji , Hoshino Masatoshi , Toyoda Hiromitsu , Hayashi Kazunori , Ohyama Shoichiro , Kishimura Yuichi , Onode Ema , Umano Masayuki , Terai Hidetomi , Nakamura Hiroaki
Published: March 2018

Study Design:

A cross-sectional study.

Objective:

To identify the best indicator for reproducible representation of craniocervical sagittal balance (CCSB).

Summary of Background Data:

Spinal sagittal balance is considered one of the most critical factors affecting the health-related quality of life. Although standard indicators of spinopelvic balance have been established, these do not include the craniocervical balance and there is no standard parameter for evaluating the CCSB.

Materials and Methods:

Six kinds of sagittal vertical axis (SVA) were drawn by a total of 9 spine or orthopedic surgeons, from the anterior margin of the external auditory canal: cranial center of gravity (CCG), C1 (center of the anterior arch), C2 (C2vb: center of the vertebral body, C2e: center of the lower endplate), and C7 (C7vb: center of the vertebral body, C7p: posterosuperior corner). Eight SVA distances were measured by using 30 radiographs; CCG–C7vb, C1–C7vb, C2e–C7vb, C2vb–C7vb, CCG–C7p, C1–C7p, C2e–C7p, and C2bv–C7p.The interobserver and intraobserver reliabilities, and the correlations between CCG and C1, C2e, or C2bv were calculated among the main groups or subgroups.

Results:

In the overall analysis, although the intraclass correlation coefficients (ICC) (1, 1) of all parameters were >0.900, the ICC (2, 1) of CCG–C7p and CCG–C7vb were <0.900. The same trends were noted in the subgroups based on observer’s experience. Comparing C7p-related and C7vb-related parameters, ICC (2, 1) showed 0.901 in C7p-related and 0.849 in C7bv-related parameters. In the analysis of the correlation between cranial SVAs, C1–C7p and C2vb–C7p SVAs correlated highly with CCG–C7p SVA (0.905, 0.805, respectively).

Conclusions:

Although the CCG SVA represents the center of the head, the current results revealed its low reproducibility. The low values were notable in those unfamiliar with craniocervical anatomy. The correlation analysis indicated that C1–C7p and C2vb–C7p SVA parameters are suitable for CCG–C7p SVA. Therefore, these 2 are considered as possible standard parameters in evaluating CCSB.

Level of Evidence:

Level III.