Central Sleep Apnea in Adults: Diagnosis and Treatment.

Background: While the literature has demonstrated a higher prevalence of moderate-to-severe obstructive sleep apnea (OSA) in the general population compared with central sleep apnea (CSA), more evidence is needed on the long-term clinical impact of and optimal treatment strategies for CSA. Observations: CSA is overrepresented among certain clinical populations, such as those with heart failure, stroke, neuromuscular disorders, and opioid use. The clinical concerns with CSA parallel those of OSA. The absence of respiration (apneas and hypopneas due to lack of effort) results in sympathetic surge, compromise of oxygenation and ventilation, sleep fragmentation, and elevation in blood pressure. Symptoms such as excessive daytime sleepiness, morning headaches, witnessed apneas, and nocturnal arrhythmias are shared between the 2 disorders. A systematic clinical approach should be used to identify and treat CSA. Conclusions: The purpose of this review is to familiarize the primary care community with CSA to aid in the identification and management of this breathing disturbance.

Operation Blood Rain Phase 2: Evaluating the Effect of Airdrop on Fresh and Stored Whole Blood.

BACKGROUND: Transfusion of whole blood (WB) is a lifesaving treatment that prolongs life until definitive surgical intervention can be performed; however, collecting WB is a time-consuming and resource-intensive process. Furthermore, it may be difficult to collect sufficient WB at the point of injury to treat critically wounded patients or multiple hemorrhaging casualties. This study is a follow-up to the proof-of-concept study on the effect of airdrop on WB. In addition, this study confirms the statistical significance for the plausibility of using airdrop to deliver WB to combat medics treating casualties in the pre-hospital setting when Food and Drug Administration (FDA)-approved cold-stored blood products are not available. METHODS: Forty-eight units of WB were collected and loaded into a blood cooler that was dropped from a fixed-wing aircraft under a Standard Airdrop Training Bundle (SATB) parachute or 68-in pilot chute. Twenty-four of these units were dropped from a C-145 aircraft, and 24 were dropped from a C-130 aircraft. A control group of 15 units of WB was storedin a blood cooler that was not dropped. Baseline and post-intervention laboratory tests were measured in both airdroppedand control units, including complete blood count; prothrombin time/partial thromboplastin time (PT/PTT); pH, lactate,potassium, bilirubin, glucose, fibrinogen, and lactate dehydrogenase (LDH) levels; and peripheral blood smears. RESULTS: The blood cooler, cooling packs, and all 48 WB units did notsustain any major damage from the airdrop. There was noevidence of hemolysis. Except for the one slightly damagedbag that was not sampled, all airdropped blood met parameters for transfusion per the Joint Trauma System Whole BloodTransfusion Clinical Practice Guideline and the Associationfor the Advancement of Blood and Biotherapies (AABB) Circular of Information for the Use of Human Blood and BloodComponents. CONCLUSIONS: Airdrop of fresh or stored WB in ablood cooler with a chute is a viable way of delivering bloodproducts to combat medics treating hemorrhaging patientsin the pre-hospital setting. This study also demonstrated theportability of this technique for multiple aircraft. The techniques evaluated in this study have the potential for utilizationin other austere settings such as wilderness medicine or humanitarian disasters where an acute need for WB delivery by airdrop is the only option.

Eye-Related Emergency Department Visits and The Opioid Epidemic: a 10-Year Analysis.

PURPOSE: To describe the epidemiology of Emergency Department (ED) visits related to opioid abuse with primary ophthalmic diagnoses in the United States (US). METHODS: This retrospective cross-sectional study used National ED Sample (NEDS) (2006-2015), a representative sample of all US EDs, to analyze and compare the epidemiology of primary ophthalmic diagnoses in opioid abusers and a control group of non-opioid users. National incidence and descriptive statistics were calculated for demographics and prevalent diagnoses. Multivariable logistic regression was used to compare outcomes between primary ophthalmic diagnoses in opioid and non-opioid abusers. RESULTS: An estimated 10,617 visits had a primary ophthalmic diagnosis and an accompanying opioid abuse diagnosis, and the incidence increased from 0.2 in 2006 to 0.6 per 100,000 US population in 2015. Opioid abuse group had more adults (6,747:63.5%) and middle-aged (3,361:31.7%) patients, while in controls adults (7,905,003:40.4%) and children (4,068,534:20.8%) were affected more. Leading etiologies were similar: traumatic and infectious etiologies were most common; however, opioid abuse patients had more severe ophthalmic diagnoses such as orbital fractures (8.4%), orbital cellulitis (7.4%), globe injury (3.4%) and endophthalmitis (3.2%) compared to controls. Patients in the opioid abuse group were also more likely to be admitted (adjusted Odds Ratio [aOR], 28.38 [95% CI, 24.50-32.87]). CONCLUSIONS: In the era of opioid crisis, an increase in ED visits with ophthalmic complaints is seen, with increasing direct and indirect costs on the healthcare system. More research is needed to establish causality and devise strategies to lower this burden.

Minimally invasive lateral approaches for the treatment of spinal tumors: single-position surgery without the "flip".

Although primary tumors of the spine and neural elements are rare, metastatic disease to the spine is quite common. Traditionally, surgical treatment for spinal tumor patients involves open decompression with or without stabilization. The single-position minimally invasive (MIS) lateral approach, which has been recently described over the recent decade, allows simultaneous access to the anterior and posterior columns with the patient positioned in the lateral decubitus position. Herein, we review the application of single-position MIS lateral surgery for the treatment of spinal neoplasm. The aim was to review the evolution, operative technique, outcomes, and complications associated with MIS lateral approaches for spinal tumors. The history of spinal tumor diagnosis and management are reviewed and discussed as well as the author's experience and literature regarding spinal tumor treatment outcome and surgical complications, with particular attention to single-position, MIS lateral approaches. In addition, the author's surgical technique is outlined in detail for thoracic, thoracolumbar and lumbar tumors. Furthermore, there are specific indications and complications associated with the surgical treatment of spinal tumors, and the MIS, single-position lateral approach, when applied appropriately, allows for concurrent access to the anterior and posterior column while mitigating the complications associated with traditional, open posterior-based approaches. In the treatment of spinal neoplasms, the goals of surgery are dictated by a number of tumor-specific and patient-specific factors. Therefore, operative treatment of tumors in the future may be a consolidation of historical surgical techniques and MIS, single-position lateral approaches. Regardless, multidisciplinary management is imperative for the individualized treatment of the patient and optimization of outcome.

Tissue-Sparing Posterior Cervical Fusion With Interfacet Cages: A Systematic Review of the Literature.

STUDY DESIGN: Literature review. OBJECTIVES: Posterior cervical interfacet cages are an alternative to lateral mass fixation in patients undergoing cervical spine surgery. Recently, a percutaneous, tissue-sparing system for interfacet cage placement has been developed, however, there is limited clinical evidence supporting its widespread use. The aim was to review studies published on this system for patient reported outcomes, radiographic outcomes, intraoperative outcomes, and complications. METHODS: Four electronic databases (PubMed, EMBASE, Scopus, and MEDLINE) were queried for original published studies that evaluated the percutaneous, tissue-sparing technique for posterior cervical fusion with interfacet cage placement. All studies reporting on open techniques and purely biomechanical studies were excluded. RESULTS: The extensive literature search returned 7852 studies. After systematic review, a total of 7 studies met inclusion criteria. Studies were independently classified as retrospective or prospective cohort studies and each assessed by the GRADE criteria. Patient reported outcomes, radiographic outcomes, intraoperative outcomes, and complications were extracted from each study and presented. CONCLUSIONS: Tissue-sparing, posterior cervical fusion with interfacet cages may be considered a safe and effective surgical intervention in patients failing conservative management for cervical spondylotic disease. However, the quality of evidence in the literature is lacking, and controlled, comparative studies are needed for definitive assessment.

Minimally invasive surgery for thoracolumbar spinal trauma.

The indications for operative intervention after thoracolumbar spine trauma have been well described. Advances in minimally invasive techniques, including percutaneous pedicle screw fixation and mini-open anterolateral retractor-based approaches can improve surgical outcomes when appropriately applied by reducing blood loss, operative duration and post-operative pain. Moreover, they allow for theoretical advantages by preservation of muscular and skeletal blood supply and innervation that is typically lost during the muscular dissection of open approaches. For thoracolumbar spine fractures, percutaneous fixation allows for internal bracing of unstable fractures during healing while maintaining sagittal alignment. In instances of neurological compromise from fracture retropulsion, corpectomies may be required, and mini-open lateral approaches adopted from degenerative disease applications allow for a minimally invasive manner to treat the defect. These further allow for placement of wide rectangular-footprint expandable vertebral body replacement devices to provide anterior column support. We believe this allows for lower rates of subsidence and helps to maintain the biomechanical integrity necessary to prevent post-traumatic malalignment and kyphosis. Together, these minimally invasive techniques combined supply the spine surgeon with a minimally invasive armamentarium to treat nearly all thoracolumbar spine trauma. Surgeons should be comfortable with the strengths and shortcomings of these approaches in order to successfully apply them for this pathology.

Acute and Hyper-acute Thoracolumbar Corpectomy for Traumatic Burst Fractures Using a Mini-open Lateral Approach.

STUDY DESIGN: Retrospective chart review. OBJECTIVE: The purpose of this study was to examine the feasibility of acute (<24 hours) and hyperacute (<8 hours) treatment of thoracolumbar burst fractures to maintain or improve spinal injury scores. SUMMARY OF BACKGROUND DATA: Historically, treatment of spinal burst fractures within 24 hours from injury was considered an "acute" treatment timeframe. Patient polytrauma triage, multiple surgical specialty, and hospital resource coordination affect time to treatment. The mini-open lateral approach for thoracolumbar corpectomy obviates the need for an approach surgeon, which may allow for early surgical intervention. METHODS: Sixteen patients treated within 24 hours with a mini-open lateral corpectomy for traumatic spinal pathology were reviewed for preoperative, perioperative, and postoperative data. Neurologic status was assessed using American Spinal Injury Association (ASIA) scores. Fractures occurred primarily from L1 to L3. Wide-footprint expandable titanium devices were used in 75% of patients. All patients received supplemental fixation. RESULTS: Average time from injury to admission to the hospital (emergency room [ER]) was 1.8 hours, with an average time from the ER to operating room (OR) of 8.2 hours and an average OR time of 2.7 hours. Eight patients required ≤8 hours from injury event to surgical initiation, whereas seven patients required between 8 and 24 hours for surgery initiation (one patient with incomplete surgical timing record). Blood loss averaged 646 mL without intraoperative complication. One perioperative complication occurred and one patient developed an asymptomatic inferior vertebral body fracture. Length of hospital stay averaged 6 days. At last follow-up, nearly all patients experienced full or near-complete neurologic recovery with at least one ASIA grade improvement seen in 73% and 20% of patients improving two grades or more. CONCLUSION: These results suggest that mini-open lateral approaches allow immediate decompression through hyperacute (<8 hours) treatment of spinal burst fractures in eligible patients. Additionally, low perioperative and postoperative morbidity allows for hastened recovery. LEVEL OF EVIDENCE: 4.

Perioperative complications in patients treated with posterior cervical fusion and bilateral cages.

CONTEXT: Posterior cervical cages have recently become available as an alternative to lateral mass fixation in patients undergoing cervical spine surgery. AIMS: The purpose of this study was to quantify the perioperative complications associated with cervical decompression and fusion in patients treated with a posterior cervical fusion (PCF) and bilateral cages. SETTINGS AND DESIGN: A retrospective, multicenter review of prospectively collected data was performed at 11 US centers. SUBJECTS AND METHODS: The charts of 89 consecutive patients with cervical radiculopathy treated surgically at one level with PCF and cages were reviewed. Three cohorts of patients were included standalone primary PCF with cages, circumferential surgery, and patients with postanterior cervical discectomy and fusion pseudarthrosis. Follow-up evaluation included clinical status and pain scale (visual analog scale). STATISTICAL ANALYSIS USED: The Wilcoxon test was used to test the differences for the data. The P level of 0.05 was considered significant. RESULTS: The mean follow-up interval was 7 months (range: 62 weeks - 2 years). The overall postsurgery complication rate was 4.3%. There were two patients with neurological complications (C5 palsy, spinal cord irritation). Two patients had postoperative complications after discharge including one with atrial fibrillation and one with a parietal stroke. After accounting for relatedness to the PCF, the overall complication rate was 3.4%. The average (median) hospital stay for all three groups was 29 h. CONCLUSIONS: The results of our study show that PCF with cages can be considered a safe alternative for patients undergoing cervical spine surgery. The procedure has a favorable overall complication profile, short length of stay, and negligible blood loss.

Outpatient Minimally Invasive Lumbar Interbody: Fusion Predictive Factors and Clinical Results.

STUDY DESIGN: Retrospective review of data from a prospective patient outcomes registry. OBJECTIVE: The object of this work was to examine patient and surgical predictors of early postoperative discharge and test the predictive model against two clinical series of outpatient minimally invasive lumbar fusion patients. SUMMARY OF BACKGROUND DATA: Outpatient and ambulatory surgery centers are regularly utilized for procedures with low-risk profiles and minimal need for extended postoperative observation, but little has been reported in lumbar spinal fusion producers. METHODS: Two analyses were undertaken, an examination of patient characteristics to determine predictors of early (<24 hours) postoperative discharge and then clinical examinations of patients treated with lumbar fusion at an ambulatory surgery center. For the predictive arm of the study, 1033 patients treated with minimally invasive (MIS) lateral interbody fusion (XLIF) were grouped according to length of postoperative hospitalization with 873 patients discharged <24 hours (outpatients), and 160 discharged >23 hours after surgery (inpatients). For the clinical studies, 54 consecutive XLIF and 18 consecutive MIS posterior fusion patients were treated at an ambulatory surgery center with demographic, treatment, and complication data collected. RESULTS: From the predictive study, the strongest baseline predictors of early postoperative discharge were a less advanced diagnosis (non-deformity), younger age, elevated baseline hemoglobin levels, and lower body mass index. The most predictive treatment variables that predicted early postoperative discharge were fewer number of levels treated and elevated postoperative hemoglobin levels.In the clinical series, outpatient surgeries were performed in younger patients (50.6 and 53.2 yr), at relatively few levels (96% of cases were at one or two levels), for simple degenerative disease. No intraoperative and few postoperatives complications were seen in either XLIF or MIS posterior fusions performed in ambulatory settings with no emergent transfers to inpatient facilities. CONCLUSION: Select patients, by health and indication, can safely be treated as outpatients with XLIF or other modern MIS approaches. Being younger, having elevated preoperative hemoglobin levels, fewer levels being treated, for less advanced disease may predict early postoperative discharge. LEVEL OF EVIDENCE: 3.

Lumbar total disc replacement by less invasive lateral approach: a report of results from two centers in the US IDE clinical trial of the XL TDR® device.

PURPOSE: To evaluate the clinical and radiographic outcomes following total disc arthroplasty using the XL TDR(®) Lumbar Disc in the treatment of patients with symptomatic degenerative disc disease at one level between L1-2 and L4-5. METHODS: Data were compiled from two centers participating in a prospective, multi-center Food and Drug Administration-approved investigational device exemption clinical trial enrolling patients with single-level lumbar degenerative disc disease unresponsive to non-operative treatment. Longitudinal outcomes were evaluated through 3-year follow-up and included patient-reported pain, function, and general health, as well as radiographic measures such as maintenance of disc height and range of motion. RESULTS: The two-center cohort included 64 treated patients, 42 % female, averaging 45.3 years of age (range 26-67). The majority of procedures were performed at the L4-5 level (75 %), uncomplicated, with minimal blood loss (88 % 0-50 cc), and in an outpatient setting (93.8 %). Postoperative events included 10 patients (15.6 %) with new hip flexion weakness, 7 (10.9 %) with new lower extremity weakness, and 10 (15.6 %) with new lower extremity sensory deficits, all resolved by 3 months in all but two patients whose deficits were prolonged but eventually resolved. Average disc height increased postoperatively from 7.2 to 12.1 mm (69 %), and was 10.7 mm (49 % increase from preoperative) at 3 years. Flexion/extension range of motion averaged 5.9° (SD 4.8°) at 3 years, and was not statistically different from preoperative (p = 0.471). Heterotopic ossification interfering with segmental motion was noted in 3 patients (10.3 %) at 3 years, none ankylosed (Grade IV). Postoperative improvement in patient-reported outcomes was significant (p < 0.01 for all measures) and maintained through 3-year follow-up. Satisfaction with results was reported by 85 % (51/60) of patients at 2 years and 93 % (28/30) at 3 years. There were no revisions through 3 years postoperative. CONCLUSIONS: The results following XL TDR show good clinical and radiographic outcomes out to 3 years postoperative, with clinically significant improvements in pain, function, and general health, few complications, and high patient satisfaction.

Mapping the kinetic and thermodynamic landscape of formaldehyde oligomerization under neutral conditions.

Density functional theory calculations, including Poisson-Boltzmann implicit solvent and free energy corrections, are applied to study the thermodynamic and kinetic free energy landscape of formaldehyde oligomerization up to the C4 species in aqueous solution at pH 7. Oligomerization via C-O bond formation leads to linear polyoxymethylene (POM) species, which are the most kinetically accessible oligomers and are marginally thermodynamically favored over their oxane ring counterparts. On the other hand, C-C bond formation via aldol reactions leads to sugars that are thermodynamically much more stable in free energy than POM species; however, the barrier to dimerization is very high. Once this initial barrier is traversed, subsequent addition of monomers to generate trimers and tetramers is kinetically more feasible. In the aldol reaction, enolization of the oligomers provides the lowest energy pathway to larger oligomers. Our study provides a baseline free energy map for further study of oligomerization reactions under catalytic conditions, and we discuss how this will lead to a better understanding of complex reaction mixtures with multiple intermediates and products.

Complications of the mini-open anterolateral approach to the thoracolumbar spine.

The mini-open anterolateral approach to the thoracolumbar spine is gaining popularity as a minimally-invasive alternative to traditional open thoracolumbar approaches. Published studies reporting and discussing the complications associated with this minimally invasive approach, however, are limited. We performed a retrospective review of patients undergoing the mini-open lateral approach to the thoracolumbar spine for corpectomy/fusion. Intraoperative and postoperative complications are reported and analyzed. Eighty consecutive patients underwent the mini-open lateral approach with corpectomy and fusion for trauma (71%), tumor (26%) and infection (3%). Total complication rate was 12.5% (dural tear 2.5%, intercostal neuralgia 2.5%, deep vein thrombosis 2.5%, pleural effusion 1.3%, wound infection 1.3%, hardware failure 1.3%, hemothorax 1.3%). Two patients needed a re-operation to address the complication (hardware failure, hemothorax). There were no postoperative neurological complications. The mini-open anterolateral approach to the thoracolumbar spine is an appealing alternative to the traditional open approaches. This technique, however, is technically demanding and requires proficiency in the use of minimally invasive spinal surgery instruments and retractors.

Dispersal of invasive forest insects via recreational firewood: a quantitative analysis.

Recreational travel is a recognized vector for the spread of invasive species in North America. However, there has been little quantitative analysis of the risks posed by such travel and the associated transport of firewood. In this study, we analyzed the risk of forest insect spread with firewood and estimated related dispersal parameters for application in geographically explicit invasion models. Our primary data source was the U.S. National Recreation Reservation Service database, which records camper reservations at > 2,500 locations nationwide. For > 7 million individual reservations made between 2004 and 2009 (including visits from Canada), we calculated the distance between visitor home address and campground location. We constructed an empirical dispersal kernel (i.e., the probability distribution of the travel distances) from these "origin-destination" data, and then fitted the data with various theoretical distributions. We found the data to be strongly leptokurtic (fat-tailed) and fairly well fit by the unbounded Johnson and lognormal distributions. Most campers ( approximately 53%) traveled <100 km, but approximately 10% traveled > 500 km (and as far as 5,500 km). Additionally, we examined the impact of geographic region, specific destinations (major national parks), and specific origin locations (major cities) on the shape of the dispersal kernel, and found that mixture distributions (i.e., theoretical distribution functions composed of multiple univariate distributions) may fit better in some circumstances. Although only a limited amount of all transported firewood is likely to be infested by forest insects, this still represents a considerable increase in dispersal potential beyond the insects' natural spread capabilities.

A comparison of perioperative charges and outcome between open and mini-open approaches for anterior lumbar discectomy and fusion.

The objectives of this study were to examine charge data and long-term outcomes of two approaches for anterior lumbar interbody fusion: a mini-open lateral approach (extreme lateral interbody fusion, XLIF) and an open anterior approach (anterior lumbar interbody fusion, ALIF) through retrospective chart review. A total of 202 patients underwent surgery: 87 with ALIF (Open) and 115 with XLIF (Mini-open) procedures, all with transpedicular fixation. Complications occurred in 16.7% of Open, and 8.2% of Mini-open, procedures (p = 0.041). The mean charges ($US) for one-level Mini-open and Open procedures were $91,995 and $102,146, and for two-level procedures were $124,540 and $144,183, respectively. All differences were statistically significant (p < 0.05). This represents a 10% cost-savings, based on charges, for one-level and 13.6% for two-level Mini-open compared to Open procedures. Functional outcomes improved significantly at two years for both cohorts, although the difference between groups was not statistically significant. In conclusion, the Mini-open approach, compared to the Open, resulted in clinical as well as cost benefits with similar long-term outcomes.

Lumbarized sacrum as a relative contraindication for lateral transpsoas interbody fusion at L5-6.

STUDY DESIGN: Retrospective review. OBJECTIVE: To determine if lumbarized sacra at the L5-6 level (functional L4-5) are a contraindication to a lateral transpsoas approach. SUMMARY OF BACKGROUND DATA: Transitional vertebrae at the lumbosacral junction present mechanical and morphologic changes, though these changes have not been characterized with respect to the feasibility of a lateral transpsoas approach. METHODS: Three hundred fifty-one patients were scheduled for lumbar interbody fusion using a mini-open lateral transpsoas approach (XLIF) at L4-5 from 2004 to 2008 at a single institution. In patients with 6 lumbar vertebrae, accessibility, based on neuromonitoring, of the L5-6 level (functional L4-5) was reviewed. Qualitative assessments using axial magnetic resonance imaging (MRI) were performed and compared with a sample of patients with normal anatomy treated at L4-5. RESULTS: Of the 351 patients scheduled for treatment at L4-5, 10 (2.8%) were determined to have 6 lumbar vertebrae with the symptomatic level at L5-6. Of those 10, 2 (20%) could be treated using a lateral transpsoas approach, and 8 (80%) were converted to another approach after a corridor through the psoas muscle was not found, based on neuromonitoring feedback. Review of axial MRI showed a teardrop-shaped psoas detached from the lateral border of the disc space in patients with transitional anatomy unapproachable at L5-6, resemblant of L5-S1 in normal anatomy. In the 2 patients who could be safely approached, the psoas anatomy at L5-6 was similar to a normal L4-5 level, with a domed/helmet shape, attached laterally to the disc space. CONCLUSIONS: Treating the L5-6 level using a lateral transpsoas approach in individuals with lumbarized sacra can be challenging due to anatomy more similar to the L5-S1 level in normal patients. Preoperative planning using axial MRI and intraoperative adherence to advanced neuromonitoring can aid in identifying and avoiding injury in these rare patients.

Minimally invasive lateral approach for symptomatic thoracic disc herniation: initial multicenter clinical experience.

OBJECT: Symptomatic herniated thoracic discs remain a surgical challenge and historically have been associated with significant complications. While neurological outcomes have improved with the abandonment of decompressive laminectomy, the attempt to minimize surgical complications and associated morbidities continues through less invasive approaches. Many of these techniques, such as thoracoscopy, have not been widely adopted due to technical difficulties. The current study was performed to examine the safety and early results of a minimally invasive lateral approach for symptomatic thoracic herniated intervertebral discs. METHODS: Sixty patients from 5 institutions were treated using a mini-open lateral approach for 75 symptomatic thoracic herniated discs with or without calcification. The mean age was 57.9 years (range 23-80 years), and 53.3% of the patients were male. Treatment levels ranged from T4-5 to T11-12, with 1-3 levels being treated (mean 1.3 levels). The most common levels treated were T11-12 (14 cases [18.7%]), T7-8 (12 cases [16%]), and T8-9 (12 cases [16%]). Symptoms included myelopathy in 70% of cases, radiculopathy in 51.7%, axial back pain in 76.7%, and bladder and/or bowel dysfunction in 26.7%. Instrumentation included an interbody spacer in all but 6 cases (10%). Supplemental internal fixation included anterolateral plating in 33.3% of cases and pedicle screws in 10%; there was no supplemental internal fixation in 56.7% of cases. Follow-up ranged from 0.5 to 24 months (mean 11.0 months). RESULTS: The median operating time, estimated blood loss, and length of stay were 182 minutes, 290 ml, and 5.0 days, respectively. Four major complications occurred (6.7%): pneumonia in 1 patient (1.7%); extrapleural free air in 1 patient (1.7%), treated with chest tube placement; new lower-extremity weakness in 1 patient (1.7%); and wound infection in posterior instrumentation in 1 patient (1.7%). Reoperations occurred in 3 cases (5%): one for posterior reexploration, one for infection in posterior instrumentation, and one for removal of symptomatic residual disc material. Back pain, measured using the visual analog scale, improved 60% from the preoperative score to the last follow-up, that is, from 7.8 to 3.1. Excellent or good overall outcomes were achieved in 80% of the patients, a fair or unchanged outcome resulted in 15%, and a poor outcome occurred in 5%. Moreover, myelopathy, radiculopathy, axial back pain, and bladder and/or bowel dysfunction improved in 83.3%, 87.0%, 91.1%, and 87.5% of cases, respectively. CONCLUSIONS: The authors' early experience with a large multicenter series suggested that the minimally invasive lateral approach is a safe, reproducible, and efficacious procedure for achieving adequate decompression in thoracic disc herniations in a less invasive manner than conventional surgical techniques and without the use of endoscopes. Symptom resolution was achieved at similar rates using this approach as compared with the most efficacious techniques in the literature, and with fewer complications in most circumstances.