Postoperative Spinal Orthoses: Types and Outcomes.

INTRODUCTION: Postoperative bracing (POB) after spinal surgery is a common practice that has been used for many decades. In the past few years, the indications, types, and outcomes of POB have been heavily questioned after many studies revealed no consistent evidence to support or refute the use of spinal orthoses after surgery. SUMMARY: Currently, there are no indications of the type, duration, or indication for many spinal orthoses and few studies have assessed their efficacy. Although much of the literature lacks adequate comparisons of brace types or specific indications, POB is still widely used for various surgical procedures. This study evaluated the current evidence concerning POB of the cervical, thoracic, and lumbosacral spine.

Emphysematous osteomyelitis of the spine: a case report and case based review of the literature.

Background/Objective: Emphysematous osteomyelitis (EO) of the spine is an uncommon type of osteomyelitis characterized by intraosseous gas-formation in the vertebrae. The objective of this report is to present a rare case of spine EO in a patient with emphysematous cystitis. A case-based review of the literature on spinal EO was also performed as an update to the relevant literature of this rare infection. Case Description/Methods: A 55-year-old female with diabetes mellitus and peripheral vascular disease (PVD) presented to our institution with recurrent falls, fatigue, and low back pain. Computed tomography (CT) and magnetic resonance imaging (MRI) scans confirmed emphysematous cystitis and EO at L4. Given the diffuse involvement, surgical intervention was deferred for IV antibiotic therapy. A case-based review was also conducted by searching the SCOPUS and PubMed databases for the following terms: "emphysematous osteomyelitis", "gas", and "spine". Only publications in English were included in this review. Key Content/Findings: Urine/blood cultures identified Klebsiella pneumoniae. After initial improvement with six weeks of broad-spectrum antibiotics, the patient re-presented with recurrent fevers and fatigue. Despite maximal medical therapy, the patient expired 2 months later due to multi-organ system failure. Including the present report, only 29 cases of spine EO have been described in the literature. Patients almost consistently presented with fever, elevated inflammatory markers, and localized pain. Most cases of spinal EO (89.7%) were monomicrobial. Escherichia coli (37.9%) and Klebsiella pneumoniae (27.6%) were the most causative organisms identified. Medical treatment universally consisted of broad-spectrum IV antibiotics prior to tailoring. Debridement and decompression, with or without fusion, were the main operative procedures performed for spine EO. Outcomes following spinal EO are varied with a 44.4% mortality rate. Conclusions: We present a case of EO of the spine and concomitant emphysematous cystitis with Klebsiella pneumoniae and a case-based review of the literature. Appropriate work up for this rare infection should include inflammatory markers, cultures, and CT/MRI imaging. Treatment consists of IV antibiotics with anaerobic and gram-negative coverage. However, treatment guidelines and operative indications for spinal emphysematous osteomyelitis remain unclear.

Osteoporosis as a Risk Factor for Intraoperative Complications and Long-term Instrumentation Failure in Patients With Scoliotic Spinal Deformity.

STUDY DESIGN: A retrospective review study. OBJECTIVE: This study aims to determine the effect of osteoporosis on spine instrumentation. SUMMARY OF BACKGROUND DATA: Osteoporosis is a common skeletal pathology that affects systemic cortical bone maintenance and remodeling. This disease accelerates the degeneration of the spine, often necessitating spinal surgery for progressive vertebral deformity, pathologic fracture, bony canal stenosis, and/or neural element decompression. There is a paucity of literature describing the role of osteoporosis as it relates to both perioperative complications and outcomes after spine fusion surgery. MATERIALS AND METHODS: A retrospective review was conducted of a prospectively maintained database for patients undergoing spine surgery between January 1, 2006 and October 3, 2017. Inclusion criteria included age 18 years and above and surgery performed for the correction of thoracolumbar scoliosis. Data collected included various demographic, clinical, and operative variables. RESULTS: A total of 532 patients met inclusion criteria, including 144 (27%) patients with a diagnosis of osteoporosis. Osteoporosis was significantly associated with increased blood volume loss (P=0.003). Postoperatively, osteoporosis was associated with increased rates of instrumentation failure (19% vs. 10%; P=0.008) and the need for revision surgery (33% vs. 16%; P<0.001). Multivariate analysis confirmed osteoporosis to be an independent risk factor for increased mean number of spinal segments fused (P<0.05), mean blood volume loss (P<0.05), rate of postoperative deep venous thrombosis/pulmonary embolism (P<0.05), rate of instrumentation failure (P<0.05), and need for revision surgery (P<0.05). CONCLUSION: Osteoporosis is a significant risk factor for instrumentation failure and need for revision surgery following arthrodesis for scoliosis correction. Furthermore, patients with osteoporosis have a significantly higher risk of intraoperative blood volume loss and postoperative thromboembolic events.

Axial Low Back Pain in Elite Athletes.

Back pain in sport is a common complaint and seen by athletes, trainers, and treating physicians. Although there are a multitude of pain generators, mechanical sources are most common. Certain sports can lead to increased mechanical and axial loading, such as competitive weightlifting and football. Common mechanical causes of pain include disk herniation and spondylolysis. Patients typically respond to early identification and conservative treatment. In others, surgical intervention is required to provide stability and prevent long-term sequelae.

Effects of menopausal state on lumbar decompression and fusion surgery.

Menopause leads to fluctuations in androgenic hormones which directly affect bone metabolism. Bone resorption, mineralization, and remodeling at fusion sites are essential in order to obtain a solid and biomechanically stable fusion mass. Bone metabolic imbalance seen in the postmenopausal state may predispose to fusion related complications. The aim of this study was to investigate fusion outcomes in lumbar spinal fusion surgery in women based on menopausal status. A retrospective analysis of all female patients who underwent posterior lumbar decompression and fusion at a single institution from 2013 to 2017 was performed. A total of 112 patients were identified and stratified into premenopausal (n = 25) and postmenopausal (n = 87) groups. Clinical and radiographic data was assessed at 1 year follow up. Postmenopausal patients had a higher rates of pseudarthrosis (11.63% vs 0%, p = 0.08), PJK (15.1% vs 4%, p = 0.14), and revision surgery (3.5% vs 0%, p = 0.35). The number of levels fused was associated with increased risk of pseudarthrosis (OR 1.4, p = 0.02); however, there was no association between age, hormonal use, prior tobacco use, or T-score. Age was associated with increased risk of developing PJK (OR = 1.11, p = 0.01); however, PJK was not associated with menopause, hormonal use, prior tobacco use, or T-score. Revision surgery was not associated with age, hormonal use, prior tobacco use, or T-score. This study suggests that postmenopausal women may be prone to have higher rates of pseudarthrosis, PJK and revision surgery, although our results were not statistically significant. Larger studies with longer follow up will help elucidate the true effects of menopause in spine surgery.

Tantalum: the next biomaterial in spine surgery?

Tantalum is a porous metal, whose elastic modulus, high frictional properties and biocompatibility make it an ideal construct to facilitate adequate bony fusion in spine surgery. Since 2015, the published literature on clinical outcomes of tantalum in spine surgery has more than doubled. A review of the literature was performed on the PubMed (MEDLINE) database on January 27, 2019, for papers pertinent to the use of tantalum metal in spine surgery. Thirteen studies were included in this review. For cervical spine, we found increased fusion rates in autograft alone compared to tantalum standalone (92.8% vs. 89.0%, P=0.001) and tantalum cages plus autograft (92.8% vs. 64.8%, P<0.0001). Complication rates in cervical fusion were lower in patients treated with tantalum standalone versus those treated with autograft (7.4% vs. 13.7%, P<0.0001), and autograft and anterior plate (7.4% vs. 33%, P=0.001). Autograft patients had higher rates of revision surgery compared to tantalum standalone (12.8% vs. 2.8%, P<0.0001) and tantalum ring with autograft (12.8% vs. 7.7%, P<0.001). For lumbar spine, we found autograft had lower fusion rate compared to tantalum standalone (80.0% vs. 93.4%, P<0.0001). Use of tantalum metal in spine fusion surgery shows promising results in fusion, complication and revision rates, and clinical outcomes compared to autograft. Although, fusion rates in short-term studies evaluating tantalum in the cervical spine are conflicting, long-term series beyond 2 years show excellent results. This early finding may be related difficulties in radiographic evaluation of fusion in the setting of tantalum cage use. Further studies are needed to further delineate the timing of fusion with the implementation of tantalum in the cervical and lumbar spine.

Isolated multiple lumbar transverse process fractures with spinal instability: an uncommon yet serious association.

PURPOSE: Isolated vertebral transverse process fractures of thoracolumbar spine without other vertebral injuries and neurological deficit are generally considered as minor injuries with no concern for associated spinal instability. This report describes a case of multiple lumbar transverse fractures associated with an unexpected yet clinically significant spinal instability. METHODS: A young male presented with right flank pain following being pushed and trapped against the ground by a reversing truck. The neurological examination was normal, and computed tomography (CT) imaging revealed multiple fractures at right transverse processes from L1 to L5, a single left-sided transverse process fracture at L2 and subtle facet joint distraction without other spinal lesions or visceral injuries. The injury was initially deemed as stable requiring symptomatic treatment and in-patient observation. However, discharge upright X-rays taken in a brace showed marked subluxation of L2/L3 and L3/L4 levels. RESULTS: Magnetic resonance imaging revealed significant discoligamentous injuries involving anterior and posterior longitudinal ligaments, annulus fibrosus as well as posterior ligamentous complex. The patient underwent posterior spinal instrumentation and fusion of L1 to L5. CONCLUSIONS: This is the first case description of association of multisegmental lumbar transverse process fractures with notoriously unstable injuries of the major soft-tissue stabilizers of the spine presenting subtle changes on CT images. When a seemingly benign spinal injury is caused by high-energy trauma, careful scrutiny for associated instability is needed. In this case, the standing in-brace X-ray was able to avoid a misdiagnosis and potentially unfavourable outcome.

High Altitude Is an Independent Risk Factor for Developing a Pulmonary Embolism, but Not a Deep Vein Thrombosis Following a 1- to 2-Level Lumbar Fusion.

STUDY DESIGN: Retrospective study. OBJECTIVE: To identify if a 1- to 2-level posterior lumbar fusion at higher altitude is an independent risk factor for postoperative deep vein thrombosis (DVT) and pulmonary embolism (PE). METHODS: A national Medicare database was queried for all patients undergoing 1- to 2-level lumbar fusions from 2005 to 2014. Those with a prior history of DVT, PE, coagulopathy, or peripheral vascular complications were excluded to better isolate altitude as the dependent variable. The groups were matched 1:1 based on age, gender, and comorbidities to limit potential cofounders. Using ZIP codes of the hospitals where the procedure occurred, we separated our patients into high (>4000 feet) and low (<100 feet) altitudes to investigate postoperative rates of DVTs and PEs at 90 days. RESULTS: Compared with lumbar fusions performed at low-altitude centers, patients undergoing the same procedure at high altitude had significantly higher PE rates (P = .010) at 90 days postoperatively, and similar rates of 90-day postoperative DVTs (P = .078). There were no significant differences in age or comorbidities between these cohorts due to our strict matching process (P = 1.00). CONCLUSION: Spinal fusions performed at altitudes >4000 feet incurred higher PE rates in the first 90 days compared with patients receiving the same surgery at <100 feet but did not incur higher rates of postoperative DVTs.

Surgical Site Infection as a Risk Factor for Long-Term Instrumentation Failure in Patients with Spinal Deformity: A Retrospective Cohort Study.

BACKGROUND: Surgical site infection (SSI) remains a complication of spine deformity surgery. Although fusion/instrumentation failure in the setting of SSI has been reported, few studies have investigated the relationship between these entities. We examine the relationship between early SSI and fusion/instrumentation failure after instrumented fusion in patients with thoracolumbar scoliosis. METHODS: A retrospective review of a prospectively maintained case series for patients undergoing spine surgery between January 1, 2006, and October 3, 2017. Inclusion criteria included age ≥18 years and surgery performed for correction of thoracolumbar scoliosis. Data collected included various demographic, clinical, and operative variables. RESULTS: 532 patients met inclusion criteria, with 20 (4%) experiencing SSI. Diabetes mellitus was the only demographic risk factor for increased SSI (P = 0.026). Number of fused levels, blood volume loss, and operative time were similar between groups. Fusion/instrumentation failure occurred in 68 (13%) patients, 10 of whom (15%) had SSI, whereas of the 464 patients with no fusion/instrumentation failure, only 10 (2%) had SSI (P < 0.001). Of the 20 patients with SSI, 10 (50%) had fusion/instrumentation failure, whereas in the 512 patients with no infection, only 58 (11%) had fusion/instrumentation failure (P < 0.001). Patients with infection also experienced significantly shorter time to fusion/instrumentation failure (P = 0.025), higher need for revision surgery (P < 0.001), and shorter time to revision surgery (P = 0.012). CONCLUSIONS: Early SSI significantly increases the risk of fusion/instrumentation failure in patients with thoracolumbar scoliotic deformity, and it significantly shortens the time to failure. Patients with early SSI have a significantly higher likelihood of requiring revision surgery and after a significantly shorter time interval.

Is There a Correlation Between Preoperative or Postoperative Vitamin D Levels with Pseudarthrosis, Hardware Failure, and Revisions After Lumbar Spine Fusion?

BACKGROUND: Vitamin D deficiency is a well-known cause of postoperative complications in patients undergoing orthopedic surgery. Orthopedic complications seen in vitamin D deficiency include nonunion, pseudarthrosis, and hardware failure. We seek to investigate the relationship between vitamin D deficiency and outcomes after lumbar spinal fusions. METHODS: A retrospective patient chart review was conducted at a single center for all patients who underwent lumbar spinal fusions from January 2015 to September 2017 with preoperative or postoperative vitamin D laboratory values. We recorded demographics, social history, medications, pre-existing medical conditions, bone density (dual-energy x-ray absorptiometry) T-scores, procedural details, 1-year postoperative Visual Analog Score (VAS), documented pseudarthrosis, revisions, and hardware failure. A total of 150 patients were initially included in the cohort for analysis. RESULTS: Overall, preoperative and postoperative vitamin D levels were not significantly associated with a vast majority of the patient characteristics studied, including comorbidities, medications, or surgical diagnoses (P > 0.05). Age at surgery was significantly associated with vitamin D levels; older patients had higher serum levels of vitamin D both preoperatively (P = 0.03) and postoperatively (P = 0.01). Those with a higher average body mass index had lower vitamin D in both groups (P = 0.02). Vitamin D levels were not significantly associated with rates of postoperative pseudarthrosis, revision, or hardware complications (P > 0.05). VAS pain score at 1 year and smoking status preoperatively or postoperatively were not associated with vitamin D levels (P > 0.05). CONCLUSIONS: Both preoperative and postoperative vitamin D levels were not significantly associated with an increased or decreased risk of pseudarthrosis, revision surgery, hardware failure, or 1-year VAS pain score after lumbar spine fusion surgery.

Short-term safety of tranexamic acid use in posterior cervical decompression and fusion surgery.

Posterior cervical decompression and fusion (PCDF) can result in substantial blood loss, leading to blood transfusions and associated complications, such as infections, hypotension and organ damage. The antifibrinolytic tranexamic acid (TXA), an inhibitor of the activation of plasminogen, has been shown to be beneficial in multiple surgical procedures without any apparent increase in postoperative complications. However, there are only few studies reporting TXA utilization in cervical spine surgery and there is currently no literature detailing the short-term safety of its use in this setting. The purpose of our study is to determine the safety profile of TXA in posterior cervical decompression and fusion. From January 2015 to April 2018, 47 patients were identified to have undergone PCDF, 19 with the utilization of a TXA protocol at our institution. The incidence of adverse events was evaluated in the perioperative period and at 1 month follow-up. Of 39 patients, Nineteen (49%) received TXA as per our instructional protocol and 20 (51%) did not. Post-operative blood was significantly reduced (453 ml vs 701 ml; p = 0.03) in the group that received TXA. There was also a significant reduction in duration of surgery associated with TXA use (269 min vs 328 min; p = 0.05). There were no complications on the first 30 days after surgical intervention on the TXA group. TXA use during PCDF is a safe, effective method to reduce postoperative blood loss. Considering the limited number of patients in this study, these results should be validated on a larger group of patients.

Fragility Fracture Risk in Elderly Patients With Cervical Myelopathy.

STUDY DESIGN: Retrospective review. OBJECTIVE: To identify and compare the incidences of fragility fractures amongst three elderly populations: the general population, patients with surgically treated cervical spondylotic myelopathy (CSM), and patients with CSM not surgically treated. SUMMARY OF BACKGROUND DATA: CSM is a common disease in the elderly. Progression of myelopathic symptoms, including gait imbalance, can be a source of morbidity as it can lead to increased falls. METHODS: Records of elderly patients with Medicare insurance from 2005 to 2014 were retrospectively reviewed. Three mutually exclusive populations of patients were identified for analysis, including a cohort of patients with a diagnosis of CSM who were not treated with surgery; a cohort of patients with CSM who were treated with surgery; and a group of control patients who had never been treated with cervical spine surgery nor were diagnosed with CSM. Incidence of fractures of the distal radius, proximal humerus, proximal femur, and lumbar spine were assessed and compared between cohorts, adjusted by age, sex, osteoporosis, dementia, cerebrovascular disease, and Charlson Comorbidity Index. RESULTS: A total of 891,864 patients were identified, of which 60,332 had a diagnosis of CSM and 24,439 underwent cervical spine surgery. Compared to general population controls, the 12-month adjusted odds of experiencing at least one fragility fracture were 1.59 times higher in patients with CSM who were not treated with surgery (P < 0.001). The analogous odds ratio was 1.34 (P < 0.001) at 3 years. Compared to nonsurgically treated patients with CSM, the odds of experiencing at least one fragility fracture were reduced to 0.89 in surgically treated patients (P = 0.008). CONCLUSION: Fragility fractures are a significant source of morbidity and mortality in elderly patients. CSM is associated with increased rates of fragility fractures, although surgical management of CSM may be protective against risk of fragility fracture. LEVEL OF EVIDENCE: 3.

A novel technique for stabilization of high-grade spondylolisthesis with transvertebral fusion without reduction.

Surgical treatment of high-grade spondylolisthesis and spondyloptosis is recommended in symptomatic patients, yet there exists much debate regarding the optimal surgical approach and the need for reduction. Similar to the Bohlman technique in that fixation is achieved across two vertebral endplates, we discuss a novel technique with the advantage of using bilateral threaded pedicle screws of large diameter and length instead of a single fibula allograft. Patients underwent posterior instrumented fusion without spondylolisthesis reduction using a novel technique placing pedicle screws with a transvertebral trajectory through the two end plates involved in the spondylolisthesis. Following screw placement, patients underwent decompression ±â€¯discectomy. Screws were connected to adjacent pedicle screws either in the upper adjacent vertebrae (i.e. L5) or the more rostral adjacent vertebrae (i.e. L4) if spinal alignment or instability necessitate including additional levels of fixation. Three patients were reviewed with ages of 67, 62, 58 years, operative times of 377-790 min, estimated blood loss 400-1050 cc, and follow-up times of 478-1082 days. There were no CSF leaks, intragenic neurologic deficits post-operatively, implant failures, revisions, or other systemic events. Two patients achieve radiographic fusion assessed by CT. At the time of final follow up, all patients were satisfied and essentially pain free. This one-stage technique offers the ability to manage local malalignment with a technique that inherently minimizes risk. The minimal complications and favorable outcomes make this technique an effective, efficient and safe procedure. Additional studies will focus on long term outcomes and should include larger patient samples.

Inpatient Outcomes After Elective Lumbar Spinal Fusion for Patients with Human Immunodeficiency Virus in the Absence of Acquired Immunodeficiency Syndrome.

BACKGROUND: To our knowledge, no prior study has evaluated outcomes after elective lumbar spinal surgery in human immunodeficiency virus (HIV) patients without acquired immunodeficiency syndrome (AIDS). This review investigated the impact of HIV-positive status (without AIDS) on outcomes after elective lumbar fusion for degenerative disc disease (DDD). METHODS: Adult patients registered in the Nationwide Inpatient Sample (2002-2011) undergoing elective lumbar fusion for DDD were extracted. Multivariable regression techniques were used to explore the association of HIV positivity with outcomes after lumbar fusion. RESULTS: This cohort included 612,000 hospitalizations (0.07% were HIV positive) of lumbar fusion for DDD. Compared with HIV-negative patients undergoing lumbar fusion, HIV-positive patients were younger (47 vs. 55 years), male (61% vs. 42%), largely insured by Medicare (30% vs. 5%), and had higher rates of chronic obstructive pulmonary disease (23.7% vs. 14.6%) (all P < 0.001) but had lower rates of obesity, hypertension, and diabetes (all P < 0.001). Multivariable models demonstrated HIV positivity to be associated with higher odds for an adverse event (odds ratio [OR], 1.92; P < 0.001), in-hospital mortality (OR, 39.91; P < 0.001), wound complications (OR, 2.60; P = 0.004), respiratory (OR, 5.43; P < 0.001) and neurologic (OR, 1.96; P = 0.039) complications, and higher costs (7.1% higher; P = 0.011) compared with non-HIV patients. There were no differences in thromboembolic events, cardiac or gastrointestinal complications, discharge disposition, or length of stay. CONCLUSIONS: Even in this selected cohort of well-controlled HIV patients, there were high complications, with concerning rates of death and respiratory complications. These data shed new light on elective spine surgery in HIV patients and may influence the treatment algorithm of surgeons who are familiar with older papers.

Changes in Cervical Alignment after Multilevel Schwab Grade II Thoracolumbar Osteotomies for Adult Spinal Deformity.

STUDY DESIGN: A retrospective cohort. OBJECTIVE: The aim of this study was to describe changes in cervical alignment (CA) and cervical deformity (CD) after multilevel Schwab Grade II Osteotomies for adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA: Reciprocal cervical and global changes after ASD surgery have not been previously described in the setting of multilevel osteotomy. METHODS: Patients with long-segment (> five levels) fusion and osteotomy for ASD were radiographically evaluated. Pre- and postoperative cervical parameters evaluated included cervical lordosis (CL), C2-C7 sagittal vertical axis (C2-C7 SVA), and the T1 slope (T1S) minus the CL (T1S-CL). CD was defined as C2-C7 SVA >4 cm, CL < 0°, or T1S-CL ≥15°. RESULTS: Eighty-five patients (mean age 64 ±â€Š11.1) were identified. Preoperative lumbar lordosis (LL) was 28.7°â€Š±â€Š13.8°, thoracic kyphosis (TK) was 28.2°â€Š±â€Š17.0°, C7 plumbline (C7 SVA) was 7.54 ±â€Š6.7 cm, pelvic tilt (PT) was 30.0°â€Š±â€Š8.96°, lumbopelvic mismatch was 32°â€Š±â€Š17.1°, and the T1 pelvic angle (TPA) was 26.8°â€Š±â€Š12.9°. The C7 SVA and TPA corrected to 3.90 cm (P < 0.0001) and 17.5°, respectively (P < 0.0001). CD increased from 41 (48%) to 47 (55%) patients. The mean CL changed from 16.5° to 11.9° (P < 0.013), C2 SVA from 10.1 to 6.37 cm (P < 0.0001), T1S-CL from 10.2° to 14.3° (P = 0.021), and TK from 28° to 39° (P < 0.0001). A correlation was observed between T1S and CL (ρ = 0.435, P < 0.0001) and C2-C7 SVA (ρ = 0.624, P < 0.0001). T1S was the only independent predictor of both the postoperative C2-C7 SVA and CL.In this study, the presence of any single preoperative CD criterion was noted to be a risk for persistent global deformity on postoperative radiograph [odds ratio (OR) = 2.5] and the development of PJK (OR = 2.1). The T1-CL < 15° may indicate an even greater risk for persistent global deformity (OR = 3.5). CONCLUSION: Thoracolumbar fusion with multilevel Schwab Grade II Osteotomies was associated with a decreased CL and reciprocal increases in TK and T1S-CL. LEVEL OF EVIDENCE: 3.

Multilevel Schwab grade II osteotomies for sagittal plane correction in the management of adult spinal deformity.

BACKGROUND CONTEXT: Prior reports have compared posterior column osteotomies with pedicle subtraction osteotomies in terms of utility for correcting fixed sagittal imbalance in adolescent patients with deformity. No prior reports have described the use of multilevel Smith-Petersen Osteotomies (SPOs) alone for surgical correction in the adult spinal deformity (ASD) population. PURPOSE: The study aimed to determine the utility of multilevel SPOs in the management of global sagittal imbalance in ASD patients. STUDY DESIGN/SETTING: This is a retrospective observational study at a single academic center. PATIENT SAMPLE: The sample included 85 ASD patients. OUTCOME MEASURES: This is a radiographic outcomes cohort study. METHODS: The radiographs of 85 ASD patients were retrospectively evaluated before and after long-segment (>5 spinal levels) fusion and multilevel SPO (≥3 levels) for sagittal imbalance correction. The number of osteotomies, correction in regional lumbar lordosis (LL), and correction per osteotomy was evaluated. Independent predictors of correction per SPO were evaluated with a hierarchical linear regression analysis. RESULTS: Eighty-five patients (mean age: 67.5±11 years) were identified with ASD (372 SPOs). The mean preoperative sagittal vertical axis (SVA) and T1 pelvic angle (TPA) were 8.16±6.75 cm and 25°±13.23°, respectively. The mean postoperative central sacral vertical line (CSVL) and SVA were 0.67±0.70 cm and 1.29±5.41 cm, respectively. The mean improvement in SVA was 6.29 cm achieved with a correction of approximately 5.05° per SPO. The mean LL restoration was 20.3°±13.9°, and 33(39%) patients achieved a final pelvic incidence minus lumbar lordosis (PI-LL) ≤10°. Fifty-four (64%) achieved a postoperative PI-LL ≤15°, 75 (88%) with a PI-LL ≤20°, and 85 (100%) achieved a PI-LL ≤25°. Correction per SPO was similar regardless of prior fusion (4.87° vs. 5.72° for revisions, p=.192). In a subgroup analysis of SVA greater than 10 cm, there was no significant difference in the final LL, thoracic kyphosis, PI-LL, SVA, CSVL, and TPA, as compared with SVA <10 cm. The LL was the only independent predictor of osteotomy correction per level (LL: ß coefficient=-0.108, confidence interval: -0.141 to 0.071, p<.0001). CONCLUSIONS: Multilevel SPOs are feasible for restoration of LL as well as sagittal and coronal alignment in the ASD population with or without prior instrumented fusion.

Prophylactic vertebral cement augmentation at the uppermost instrumented vertebra and rostral adjacent vertebra for the prevention of proximal junctional kyphosis and failure following long-segment fusion for adult spinal deformity.

BACKGROUND CONTEXT: Proximal junctional kyphosis (PJK) and proximal junctional failure (PJF) are common problems after long-segment (>5 levels) thoracolumbar instrumented fusions in the treatment of adult spinal deformity (ASD). No specific surgical strategy has definitively been shown to lower the risk of PJK as the result of a multifactorial etiology. PURPOSE: The study aimed to assess the incidence of PJK and PJF in patients treated with prophylactic polymethylmethacrylate (PMMA) cement augmentation at the uppermost instrumented vertebrae (UIV) and rostral adjacent vertebrae (UIV+1). STUDY DESIGN/SETTING: This is a retrospective cohort-matched surgical case series at an academic institutional setting. PATIENT SAMPLE: Eighty-five adult patients over a 16-year enrollment period were identified with long-segment (>5 levels) posterior thoracolumbar instrumented fusions for ASD. OUTCOME MEASURES: Primary outcomes measures were PJK magnitude and PJF formation. Secondary outcomes measures were spinopelvic parameters, as well as global and regional sagittal alignment. METHODS: The impact of adjunctive PMMA use in long-segment (≥5 levels) fusion for ASD was assessed in adult patients aged 18 and older. Patients were included with at least one of the following: lumbar scoliosis >20°, pelvic tilt >25°, sagittal vertical axis >5 cm, central sacral vertical line >2 cm, and thoracic kyphosis >60°. The frequency of PJF and the magnitude of PJK were measured radiographically preoperatively, postoperatively, and at maximum follow-up in controls (Group A) and PMMA at the UIV and UIV+1 (Group B). RESULTS: Eighty-five patients (64±11.1 years) with ASD were identified: 47 control patients (58±10.6) and 38 patients (71±6.8) treated with PMMA at the UIV and UIV+1. The mean follow-up was 27.9 and 24.2 months in Groups A and B, respectively (p=.10). Preoperative radiographic parameters were not significantly different, except the pelvic tilt which was greater in Group A (26.6° vs. 31.4°, p=.03). Postoperatively, the lumbopelvic mismatch was greater in Group B (14.6° vs. 7.9°, p=.037), whereas the magnitude of PJK was greater in controls (9.36° vs. 5.65°, p=.023). The incidence of PJK was 36% (n=17) and 23.7% (n=9) in Groups A and B, respectively (p=.020). The odds ratio of PJK with vertebroplasty was 0.548 (95% confidence interval=0.211 to 1.424). Proximal junctional kyphosis was observed in 6 (12.8%) controls only (p=.031). The UIV+1 angle, a measure of PJK, was significantly greater in controls (10.0° vs. 6.8°, p=.02). No difference in blood loss was observed. No complications were attributed to PMMA use. CONCLUSIONS: The use of prophylactic vertebral cement augmentation at the UIV and rostral adjacent vertebral segment at the time of deformity correction appears to be preventative in the development of proximal junctional kyphosis and failure.

Excision of a centrally based ventral intradural extramedullary tumor of the cervical spine through a direct posterior approach.

INTRODUCTION: Intradural extramedullary (IDEM) tumors of the cervical spine are removed through an assortment of surgical approaches including: dorsolateral, ventrolateral, and anterior or transoral. Historically, midline ventral IDEM tumors are ostensibly thought to be unfavorable candidates for removal through a direct posterior approach. A case report of a patient with a ventrally based centrally located meningioma in the upper cervical spine (C2/C3) that was removed with direct posterior approach is described. CASE PRESENTATION: A 51-year-old male presented with cervicalgia and radiating scapular pain following a remote motor vehicle collision. A ventrally located meningioma in relation to the C2 body was noted on MRI. Management of this patient included obtaining adequate exposure through a posterior approach, complete tumor excision, and maintenance of cervical spine stability. Cervical stability was maintained following total unilateral facetectomy and application of instrumentation from C1-C3. DISCUSSION: Subsequent to tumor removal, the patient had complete resolution of his cervicalgia, headaches, and scapular pain by his two month follow-up appointment. Although adhesions can make total resection difficult, a posterior approach can grant adequate access to midline ventral meningiomas. Cervical spine stability, tumor location, infection risk, and surgeon familiarity with the approach should all be weighed in decision-making.

Blunt impacts to the back: Biomechanical response for model development.

The development of advanced injury prediction models requires biomechanical and injury tolerance information for all regions of the body. While numerous studies have investigated injury mechanics of the thorax under frontal impact, there remains a dearth of information on the injury mechanics of the torso under blunt impact to the back. A series of hub-impact tests were performed to the back surface of the mid-thorax of four mid-size male cadavers. Repeated tests were performed to characterize the biomechanical and injury response of the thorax under various impact speeds (1.5m/s, 3m/s and 5.5m/s). Deformation of the chest was recorded with a 59-gage chestband. Subject kinematics were also recorded with a high-speed optoelectronic 3D motion capture system. In the highest-severity tests, peak impact forces ranged from 6.9 to 10.5 kN. The peak change in extension angle measured between the 1st thoracic vertebra and the lumbar spine ranged from 39 to 62°. The most commonly observed injuries were strains of the costovertebral/costotransverse joint complexes, rib fractures, and strains of the interspinous and supraspinous ligaments. The majority of the rib fractures occurred in the rib neck between the costovertebral and costotransverse joints. The prevalence of rib-neck fractures suggests a novel, indirect loading mechanism resulting from bending moments generated in the rib necks caused by motion of the spine. In addition to the injury information, the biomechanical responses quantified here will facilitate the future development and validation of human body models for predicting injury risk during impact to the back.