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Finite-element analysis. Intraoperative contouring of rods is a common procedure for spine surgeons to match the native curvature of the spine, but it may lead to premature weakening of the rod. This study investigated the effect of different bending methods on rod fatigue performance. Rod failure in the cervical spine is of clinical concern, particularly when spanning the cervicothoracic region and when considering corrective osteotomies for deformity correction and global spinal alignment. Finite-element models were developed to simulate rod bending (3.5 mm D, 40 mm L) to achieve a 23° angle with 3 different bending methods: French single, multiple bending, and in situ bending. Simulations were conducted in 4 steps: rod bending, rod spring back, residual stress relaxation, and F1717 mechanical test simulation. French single bending resulted in the highest residual stress concentrations for both titanium (TiAlV) and cobalt chrome (CoCr) at 783 MPa and 507 MPa, respectively. During F1717 test simulation, the French single bent rod had its highest tensile stress in the middle, with 917 MPa and 623 MPa, respectively, for TiAlV and CoCr, compared to in situ (580 MPa and 586 MPa for TiAlV and CoCr) and the French multiple bent rod (765 MPa and 619 MPa for TiAlV and CoCr). The computational model found that CoCr rods made the construct least prone to deformation. French single bend with TiAlV rods put the construct at highest risk of failure. CoCr rods led to minimal physical changes in microstructure while showing evidence of flattening.

Objective To compare modified expansive laminoplasty and fusion (MELF) with anterior cervical corpectomy and fusion (ACCF), and anterior cervical discectomy and fusion (ACDF), in treating four-level cervical spondylotic myelopathy (CSM). Methods This retrospective study included patients with four-level CSM who had undergone surgery at the Affiliated Hospital of Qingdao University between January 2013 and May 2015. D-values, Cobb’s angle, Japanese Orthopaedic Association (JOA) score and quality of life (SF-36 scores) were compared between patients treated with ACCF/ACDF versus MELF. Results Twenty-six patients who underwent ACCF/ACDF and 26 who underwent MELF were included, and all showed bone fusion following treatment. The most common complications were dysphasia (12/26) in the ACCF/ACDF group and axial neck pain (7/26) in the MELF group. C5 nerve root palsy was not observed in either group. D value and Cobb’s angle changes showed that ACDF/ACCF was more effective in curve correction than MELF. Postoperative improvements in JOA and SF-36 scores were noted in both groups, with no statistically significant between-group differences. Conclusion Anterior and posterior approaches may produce similar clinical outcomes in the surgical management of four-level CSM. MELF may avoid known complications of the posterior approach.

Study Design: In vitro biomechanical study. Objectives: The objective of this in vitro biomechanical range-of-motion (ROM) study was to evaluate spinal segmental stability following fixation with a novel anterior cervical discectomy and fusion (ACDF) device (“novel device”) that possesses integrated and modular no-profile, half-plate, and full-plate fixation capabilities. Methods: Human cadaveric (n = 18, C3-T1) specimens were divided into 3 groups (n = 6/group). Each group would receive one novel device iteration. Specimen terminal ends were potted. Each specimen was first tested in an intact state, followed by anterior discectomy (C5/C6) and iterative instrumentation. Testing order: (1) novel device (group 1, no-profile; group 2, half-plate; group 3, full-plate); (2) novel device (all groups) with lateral mass screws (LMS); (3) traditional ACDF plate + cage; (4) traditional ACDF plate + cage + LMS. A 2 N·m moment was applied in flexion/extension (FE), lateral bending (LB), and axial rotation (AR) via a kinematic testing machine. Segmental ROM was tracked and normalized to intact conditions. Comparative statistical analyses were performed. Results: Key findings: (1) the novel half- and full-plate constructs provided comparable reduction in FE and LB ROM to that of traditional plated ACDF ( P ≥ .05); (2) the novel full-plate construct significantly exceeded all other anterior-only constructs ( P ≤ .05) in AR ROM reduction; and (3) the novel half-plate construct significantly exceeded the no-profile construct in FE ( P < .05). Conclusions: The novel ACDF device may be a versatile alternative to traditional no-profile and independent plating techniques, as it provides comparable ROM reduction in all principle motion directions, across all device iterations.

Mature thoracic intraspinal teratomas are rare tumors in adults. In this case study, we present a case of intradural, extramedullary teratoma, which was surgically resected. A 50 year old man presented with progressive bilateral leg pain, severe myelopathy and weakness. Magnetic Resonance Imaging (MRI) revealed a cystic mass lesion in the T11-12 region region. Microsurgical resection of the tumor using CO2 laser with neuromonitoring was performed. Postoperatively, the patient had a remarkable clinical improvement. Mature spinal teratomas are rare, slow growing spinal tumors. Surgical resection provides excellent recovery, and recurrence rates are low.

Study Design: Cadaveric study. Objective: To evaluate accuracy, radiation exposure, and surgical time of a new robotic-assisted navigation (RAN) platform compared with freehand techniques in conventional open and percutaneous procedures. Methods: Ten board-certified surgeons inserted 16 pedicle screws at T10–L5 (n = 40 per technique) in 10 human cadaveric torsos. Pedicle screws were inserted with (1) conventional MIS technique (L2–L5, patient left pedicles), (2) MIS RAN (L2–L5, patient right pedicles), (3) conventional open technique (T10–L1, patient left pedicles), and (4) open RAN (T10–L1, patient right pedicles). Output included (1) operative time, (2) number of fluoroscopic images, and (3) screw accuracy. Results: In the MIS group, compared with the freehand technique, RAN allowed for use of larger screws (diameter: 6.6 ± 0.6 mm vs 6.3 ± 0.5 mm; length: 50.3 ± 4.1 mm vs 46.9 ± 3.5 mm), decreased the number of breaches >2 mm (0 vs 7), fewer fluoroscopic images (0 ± 0 vs 108.3 ± 30.9), and surgical procedure time per screw (3.6 ± 0.4 minutes vs 7.6 ± 2.0 minutes) (all P < .05). Similarly, in the open group, RAN allowed for use of longer screws (46.1 ± 4.1 mm vs 44.0 ± 3.8 mm), decreased the number of breaches >2 mm (0 vs 13), fewer fluoroscopic images (0 ± 0 vs 24.1 ± 25.8) (all P < .05), but increased total surgical procedure time (41.4 ± 8.8 minutes vs 24.7 ± 7.0 minutes, P = .000) while maintaining screw insertion time (3.31.4 minutes vs 3.1 ± 1.0 minutes, P = .650). Conclusion: RAN significantly improved accuracy and decreased radiation exposure in comparison to freehand techniques in both conventional open and percutaneous surgical procedures in cadavers. RAN significantly increased setup time compared with both conventional procedures.

Objective Traditionally, laminectomy has been the preferred surgical approach for the resection of intradural spinal tumors. Recent trends towards minimally invasive techniques have generated interest in hemilaminectomy as an effective alternative surgical approach to resect spinal tumors. However, it remains unclear if the potential benefits of hemilaminectomies, used in other routine spinal procedures, apply to intradural spinal tumors. This report presents a six-year single institutional analysis of open resection of intradural tumors using laminectomies as compared to hemilaminectomies. Methods A single institution, multisurgeon, retrospective review of 52 patients undergoing resection of intradural spinal tumors over a six-year period was performed. Estimated blood loss, operative time, post-operative complications, length of stay, and post-operative clinical spinal instability were analyzed and compared between the two surgical techniques. Results The mean follow-up was 34 and 20 months for the laminectomy and hemilaminectomy groups, respectively. There was no statistically significant difference in operative times between the two groups (hemilaminectomy: 250.13±76.44 minutes, laminectomy: 244.49±92.85 minutes; p=0.43).Similarly, there was no difference in overall estimated blood loss (hemilaminectomy: 125±74 cc, laminectomy: 256.05±320.8 cc; p=0.27) or mean hospital length of stay (hemilaminectomy: 4.00±2.12 days, laminectomy: 5.26±3.0 days; p=0.60).No patient in either surgical group had post-operative evidence of clinical spinal instability. Conclusion Hemilaminectomy is a viable approach for the resection of intradural spinal tumors, with similar rates of post-operative complications to laminectomy when using an open surgical approach. The laminectomy allows for bilateral exposure of the entire spinal canal and neural foramina; and continues to be the preferred method for resection of large tumors with complex morphology.

Background: Tarlov cyst disease is a collection of cerebrospinal fluid between the endoneurium and perineurium of spinal, usually sacral, nerve roots. These cysts can become symptomatic in 20% of patients, causing lower back pain, radiculopathy, bladder and bowel dysfunction necessitating medical or surgical intervention. Different surgical and non-surgical modalities have been described for the treatment of symptomatic Tarlov cysts. However, there has been no published study that examined types of surgical techniques side by side. Our study presents a preliminary experience in the surgical management of symptomatic Tarlov cysts using two surgical techniques: cyst fenestration and nerve root imbrication. Methods: Retrospective chart review and analysis was done for all patients who underwent surgical intervention for symptomatic Tarlov cyst(s) in the period 2007–2013. Operative reports, preoperative and postoperative clinic visit reports were reviewed. The surgical techniques of cyst fenestration and nerve root imbrication were each described in terms of intraoperative parameters, hospital course and outcome. Modified MacNab criteria were used for evaluation of the final clinical outcome. Results: Thirty-six surgical patients were identified. Three had repeat surgery (total of 39 operations). The median age was 51 years (range, 26–84 years). Eighty-six percent were females. The presenting symptoms were low back pain (94%), sensory radiculopathy (69%), bladder and bowel dysfunction (61%), sexual dysfunction (17%) and motor dysfunction (8%). Cyst fenestration was performed in 12 patients (31%) and nerve root imbrication was done in 27 (69%). All patients in the fenestration group but only 67% in the imbrication group had fibrin glue injection into the cyst or around the reconstructed nerve root. The overall surgery-related complication rate was 28%. The complication rate was 5/12 (42%) in the fenestration group and 6/27 (22%) in the imbrication group. At the time of the last clinic visit, improved clinical outcome was noted in 9/11 (82%) and 20/25 (80%) in the fenestration and the imbrication group, respectively. Conclusions: Cyst fenestration and nerve root imbrication are both surgical techniques to treat symptomatic Tarlov cyst(s), and both can result in clinical improvement.

We will review the recent literature concerning the necessity of supplemental fusion to spinal instrumentation and discuss if temporal spinal fixation is a viable option for the treatment of unstable spine fractures. Advancements in minimally invasive techniques offer an alternative approach to traditional open stabilization for unstable spine fractures. The use of minimally invasive surgery offers many advantages concerning operative morbidly; fusion is not utilized and instrumentation can be removed in a delayed fashion. There are limited differences in amount of correction loss over time, and multiple studies report equivocal to superior results in patient’s functional outcomes when comparing temporary internal stabilization to long segment instrumentation with fusion. Removal of implants can restore segmental motion. Review of the literature demonstrates that temporary internal stabilization for unstable fractures is a viable option. Close clinical and radiographic follow-up is recommended to avoid delayed spinal deformity.

Craniocervical traumatic injuries affect the skull base, atlas and/or axis, and account for a minority of cervical injuries. The craniocervical junction is biomechanically responsible for the majority of axial rotation at the atlantoaxial complex and the greatest range of flexion/extension at the occipital-C1 joint. Therefore, identifying appropriate surgical indications is essential. The goals of occipitocervical fusion are neurological improvement, biomechanical stability, and correction of imbalance. Significant advances in surgical technique, hardware, and technology have occurred. Currently, the plate–screw–rod arthrodesis technique is the most effective technique. In the future, biomechanical studies and intraoperative navigation may reduce potential intraoperative and postoperative complications.

Study Design Prospective study. Objective Because single-level disk arthroplasty or arthrodesis in the lower subaxial spine improves headaches after surgery, we studied whether this effect may be better appreciated after two-level arthroplasty. Methods We performed an independent post hoc analysis of two concurrent prospective randomized investigational device exemption trials for cervical spondylosis, one for single-level treatment and the other for two adjacent-level treatments. Results For the one-level study, baseline mean headache scores significantly improved at 60 months for both the cervical disk arthroplasty (CDA) and anterior cervical diskectomy and fusion (ACDF) groups ( p Conclusion Both CDA and ACDF at either one or two levels are associated with sustained headache relief from baseline. Patients undergoing two-level arthroplasty had significantly greater improvement in headache at all points except for at 18 and 60 months. This difference in improvement was not observed in patients undergoing single-level arthroplasty. The mechanism of greater headache relief after two-level arthroplasty remains unclear.

BACKGROUND CONTEXT Anterior column realignment is a minimally invasive technique that uses a lateral transpsoas interbody approach with anterior longitudinal ligament (ALL) release, which aims to restore sagittal alignment. Resection of the ALL enables use of expandable lateral lumbar interbody fusion (LLIF) spacers with larger implant heights and lordosis, increasing focal lordosis correction and minimizing endplate mismatch. The relationship between implant height and lordosis selection, and their effect on segmental lordosis correction and anterior-posterior endplate loading, is poorly understood. PURPOSE The aim of this study is to quantify lordosis correction and endplate force distribution using an adjustable-lordosis expandable LLIF spacer. STUDY DESIGN/SETTING In vitro human cadaveric study. PATIENT SAMPLE A total of seven cadaveric specimens. OUTCOME MEASURES Lordosis and anterior-posterior endplate forces. METHODS Seven L4–L5 cadaveric segments were used. A 55 lb axial load was applied to L4 to simulate intraoperative loads. Segments were instrumented with bilateral pedicle screws and a sequence of expandable spacers with anterior fixation at varied heights and implant lordosis (ten constructs), including (A) 0°, 6°, and 20° lordosis with intact ALL; B) 20° and 30° lordosis following ALL resection. Segmental lordosis and endplate force-maps were collected. An equivalent loading ratio (ELR=anterior load/total load*100%) was calculated; ELR=80% refers to 80% anterior and 20% posterior edge loading. ELR was statistically compared to 50%, which is equivalent anterior-posterior loading. RESULTS The mean intact L4–L5 lordosis was 11.5°±3.0°. With the ALL intact, the 20° spacer without expansion increased lordosis to 11.9°±3.6° (p>0.05). Following ALL resection, use of 20° spacer with largest expansions (14.7 and 17.4 mm) significantly increased lordosis to 19.4°±4.5° (p=0.036 and 22.5°±4.9° (p CONCLUSIONS This study suggests that expandable spacers may help to balance anterior-posterior endplate loading while maximizing lordosis correction. Following ALL release, hyperlordotic spacers do not increase anterior loading, therefore, spacers may be selected for maximum lordosis. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

BACKGROUND CONTEXT For restoration of sagittal alignment, hyperlordotic lateral lumbar interbody fusion (LLIF) spacers are available as expandable or static spacers with many sizes, and possess up to 30° of implant lordosis to maximize lumbar lordosis when used in combination with anterior longitudinal ligament (ALL) resection. However, angular mismatch between the implant and vertebral endplates may play a role in subsidence due to asymmetric loading of the anterior implant edge. The relationship between implant size and their effect on segmental lordosis correction and anterior-posterior endplate loading is poorly understood. PURPOSE The aim of this study is to compare adjustable-lordosis expandable and static LLIF spacers in regards to lordosis correction and endplate force distribution. STUDY DESIGN/SETTING In vitro human cadaveric study. PATIENT SAMPLE A total of 14 cadaveric specimens. OUTCOME MEASURES Lordosis and anterior-posterior endplate forces. METHODS Fourteen L4–L5 cadaveric segments were used. A 55 lb axial load was applied to L4 to simulate intraoperative loads. Segments were instrumented with bilateral pedicle screws and a sequence of expandable spacers with anterior fixation (n=7) or static spacers (n=7) at varied heights and implant lordosis matched between spacers (nine constructs per spacer), including (A three height and lordosis combinations with intact ALL; and B) six height and lordosis combinations following ALL resection. Segmental lordosis and endplate force-maps were collected and compared between the two spacers. An equivalent loading ratio (ELR=anterior load/total load*100%) was calculated; ELR=80% refers to 80% anterior and 20% posterior edge loading. An ELR of 50% is equivalent anterior-posterior loading. RESULTS No significant differences in lordosis was observed between spacers except at between the 20° expandable spacer (17.4mm) and the 13mm 20° static spacer (22.5°±4.9° and 16.7°±2.3°, respectively, p=0.020). Equivalent anterior-posterior loading ratios were also quantified. Prior to ALL resection, the 9mm 10° static spacer had a significantly larger ELR than the 20° expandable spacer (11.5mm, p=0.016), indicating more anterior loading with the static spacer (91.5% ± 7.6 versus 70.5% ± 18.8%). Following ALL resection, the 11mm 10°, 11mm 20°, and 13mm 20° static spacers (85.1%, 99.2%, and 94.8%, respectively) all had significantly larger ELRs than the 20° expandable at 11.5mm, 14.7mm, and 17.4mm heights (52.0%, 70.0%, and 76.2%), respectively (p CONCLUSIONS This study suggests that expandable and static spacers have comparable lordosis correction; however, greater anterior endplate loading was observed with static spacers. Increased anterior endplate loading may lead to subsidence. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

BackgroundRigid interspinous process fixation (ISPF) has received consideration as an efficient, minimally disruptive technique in supporting lumbar interbody fusion. However, despite advantageous intraoperative utility, limited evidence exists characterizing midterm to long-term clinical outcomes with ISPF. The objective of this multicenter study was to prospectively assess patients receiving single-level anterior (ALIF) or lateral (LLIF) lumbar interbody fusion with adjunctive ISPF.MethodsThis was a prospective, randomized, multicenter (11 investigators), noninferiority trial. All patients received single-level ALIF or LLIF with supplemental ISPF (n = 66) or pedicle screw fixation (PSF; n = 37) for degenerative disc disease and/or spondylolisthesis (grade ≤2). The randomization patient ratio was 2:1, ISPF/PSF. Perioperative and follow-up outcomes were collected (6 weeks, 3 months, 6 months, and 12 months).ResultsFor ISPF patients, mean posterior intraoperative outcomes were: blood loss, 70.9 mL; operating time, 52.2 minutes; incision length, 5.5 cm; and fluoroscopic imaging time, 10.4 seconds. Statistically significant improvement in patient Oswestry Disability Index scores were achieved by just 6 weeks after operation (P

Background: Percutaneous endoscopic discectomy (PED) includes 2 main procedures: percutaneous endoscopic lumbar discectomy (PELD) and percutaneous endoscopic interlaminar discectomy (PEID), both of which are minimally invasive surgical procedures that effectively deal with lumbar degenerative disorders. Because of the challenging learning curve for the surgeon and the individual characteristics of each patient, preventing and avoiding complications is difficult. The most common complications, such as nucleus pulposus omission, nerve root injury, dural tear, visceral injury, nerve root induced hyperalgesia or burning-like nerve root pain, postoperative dysesthesia, posterior neck pain, and surgical site infection, are difficult to avoid; however, more focus on these issues perioperatively may be in order. Additionally, unique and unexpected complications can also occur, such as retroperitoneal hematoma (RPH), intraoperative seizures, and thrombophlebitis, among others. Objective: We aim to delineate unique complications during PED and accumulate strategies to prevent significant morbidity and improve surgical techniques. Study Design: A retrospective cohort study of patients undergoing PEID or PELD from October 2014 to January 2016. Setting: Affiliated hospitals of Qingdao University. Methods: Patients with lumbar disc herniation (LDH) who underwent PEID and PELD were retrospectively analyzed. Complications were recorded and analyzed pre and postoperatively. We assessed clinical outcomes using the visual analog scale (VAS) and Oswestry Disability Index (ODI) and classified the results into “excellent,” “good,” “fair,” or “poor” based on the modified MacNab criteria. All of the patients were followed for more than one year to evaluate their recovery from complications. Results: From October 2014 to January 2016, 426 patients with LDH underwent PEID (106 cases) or PELD (320 cases). Common complications and occurrence rates were as follows: the incomplete removal of herniated discs was 1.4% (6/426), recurrence 2.8% (12/426), nerve root injury 1.2% (5/426), dural tear 0.9% (4/426), and nerve root induced hyperalgesia or burning-like nerve root pain 2.3% (10/426); no posterior neck pain or surgical site infection occurred. Unique complications included: passage of the working channel through the spinal canal into the disc space (one case), super-elastic nerve hook caught by exiting nerve root (one case), epidural hematoma (one case), radicular artery injury and massive bleeding (one case) which was revised by micro-endoscopic discectomy, and intraoperative seizure (one case). No serious consequences occurred after active medical intervention, and most patients had good recovery by 3 months postoperatively with physical therapy. Limitations: The main limitations of this study are the retrospective study design, limited case number, and short follow-up period. Conclusions: PEDs are effective and minimally invasive methods for the surgical treatment of LDH, causing fewer complications due to the very minimal operational trauma for the muscle-ligament complex and stability of the spine. Nevertheless, because of the difficult learning curve for surgeons, lack of experience with the requisite surgical techniques, and enhanced clinical responsibility, a variety of problems may occur. Especially concerning are the unique complications mentioned here, which potentially lead to severe injury for the patient and require diligent preventive measures. Key words: Unique complications, epidural, hematoma, interlaminar, transforaminal, PEID, PELD

While management of appendicular fractures has been well described in the setting of osteopetrosis, there is limited information on managing fractures of the axial spine. Here we present an osteopetrotic patient with multiple traumatic multiple, comminuted, unstable cervical spinal fractures managed with non-operative stabilization, and provide a review of the pathophysiology, genetic characteristics, and special considerations that must be explored when determining operative versus non-operative management of spinal injury in osteopetrosis. A PubMed query was performed for English articles in the literature published up to June 2016, and used the following search terms alone and in combination: "osteopetrosis", "spine", "fractures", "osteoclasts", and "operative management". Within four months after initial injury, treatment with halo vest allowed for adequate healing. The patient was asymptomatic with cervical spine dynamic radiographs confirming stability at four months. On four-year follow up examination, the patient remained without neck pain, and CT scan demonstrated partially sclerotic fracture lines with appropriate anatomical alignment. In conclusion, external halo stabilization may be an effective option for treatment of multiple unstable acute traumatic cervical spine fractures in patients with osteopetrosis. Given the challenge of surgical stabilization in osteopetrosis, further research is necessary to elucidate the optimal form of treatment in this select patient population.

Cerebrospinal fluid (CSF) leak is a rare but potentially troublesome and occasionally catastrophic complication after anterior cervical decompression surgery. There is limited literature describing this complication, and the management of CSF leak varies. The aim of this study was to retrospectively review the treatment of cases with CSF leak and develop a management algorithm. A series of 14 patients with CSF leak from January 2011 to May 2016 were included in this study. Their characteristics, management of CSF leak, and outcomes were documented. There were 5 male and 9 female patients. Mean age at surgery was 57.1±9.9 years (range, 37–76 years). All instances of CSF leak, except 1 noted postoperatively, were indirectly repaired intraoperatively. A closed straight wound drain was placed for all patients. A lumbar subarachnoid drain was placed immediately after surgery in 4 patients and postoperatively in 7 patients. In 1 patient, lumbar drain placement was unsuccessful. In 2 additional patients, the surgeon decided not to place a lumbar drain. One patient developed meningitis and recovered after antibiotic therapy with meropenem and vancomycin. Another patient had a deep wound infection and required a revision surgery. Wound drains and lumbar drains should be immediately considered when CSF leak is identified. Antibiotics also should be considered to prevent intradural infection. [ Orthopedics. 2018; 41(2):e283–e288.]

Posterior neck deformity with an unsightly crater-like defect may result after cervicothoracic laminectomies. The authors present a new technique, spinous process reconstruction, to address this problem. A 64-year-old man presented with progressive quadriparesis secondary to cervical spondylotic myelopathy. Previously he had undergone multiple neck surgeries including cervicothoracic decompressive laminectomy. Postoperatively, he developed severe craniocervical spinal deformity and a large painful concave surgical defect in the neck. The authors performed craniocervical decompression and craniocervicothoracic instrumented stabilization. At the same time, cervicothoracic spinous process reconstruction was performed using titanium mesh to address the defect. Cervicothoracic decompressive laminectomy results in varying degrees of neck defect with resulting unsightly and an often painful surgical wound defect despite an appropriate multilayer closure. The presented spinous process reconstruction is a simple technique to address this problem with good clinical outcome.

To compare radiologic and clinical outcomes, including rates of dysphagia and dysphonia, using a no-profile stand-alone intervertebral spacer with integrated screw fixation versus an anterior cervical plate and spacer construct for single-level anterior cervical discectomy and fusion (ACDF) procedures.This multicenter, randomized, prospective study included 54 patients with degenerative disc disease requiring ACDF at a single level at C3-C7. Twenty-six patients underwent single-level ACDF with stand-alone spacers, and 28 with plate fixation and spacers. Analyses were based on comparison of perioperative outcomes, radiologic and clinical metrics, and incidence of dysphagia and/or dysphonia.Mean patient age was 48.8 ± 10.1years (53.7% female). No significant differences were observed between groups in operative time (101.8 ± 34.4 minutes, 114.4 ± 31.5 minutes), estimated blood loss (44.8 ± 76.5 mL, 82.5 ± 195.1 mL), or length of hospital stay (1.2 ± 0.6 days, 1.3 ± 0.6 days). Mean visual analog scale pain scores and Neck Disability Index scores improved significantly from preoperative to last follow-up (10.8 ± 2.6 months) in both groups (P0.05). Mean Voice Handicap Index and Eating Assessment Tool scores improved significantly from discharge to last follow-up in both groups (P0.05). From discharge to 6 months, the stand-alone spacers group consistently demonstrated greater improvement in Voice Handicap Index. Preoperative intervertebral disc and neuroforaminal heights increased significantly across treatment groups (P0.01), and no cases required surgical revision at index or adjacent levels.Anterior cervical discectomy and fusion with stand-alone spacers resulted in similar clinical and radiologic outcomes as compared with plate and spacers and may help minimize postoperative dysphonia.

Arthrodesis of the sacroiliac joint (SIJ) for surgical treatment of SIJ dysfunction has regained interest among spine specialists. Current techniques described in the literature most often utilize intraoperative fluoroscopy to aid in implant placement; however, image guidance for SIJ fusion may allow for minimally invasive percutaneous instrumentation with more precise implant placement. In the following cases, we performed percutaneous stereotactic navigated sacroiliac instrumentation using O-arm® multidimensional surgical imaging with StealthStation® navigation (Medtronic, Inc. Minneapolis, MN). Patients were positioned prone and an image-guidance reference frame was placed contralateral to the surgical site. O-arm® integrated with StealthStation® allowed immediate auto-registration. The skin incision was planned with an image-guidance probe. An image-guided awl, drill and tap were utilized to choose a starting point and trajectory. Threaded titanium cage(s) packed with autograft and/or allograft were then placed. O-arm® image-guidance allowed for implant placement in the SIJ with a small skin incision. However, we could not track the cage depth position with our current system, and in one patient, the SIJ cage had to be revised secondary to the anterior breach of sacrum.

The aim of this study is to evaluate the capability of femtosecond Laser Induced Breakdown Spectroscopy (fsLIBS) to discriminate between normal and cancerous bone, with implications to femtosecond laser surgery procedures. The main advantage of using femtosecond lasers for surgery is that the same laser that is being used to ablate can also be used for a feedback system to prevent ablation of certain tissues. For bone tumor removal, this technique has the potential to reduce the number of repeat surgeries that currently must be performed due to incomplete removal of the tumor mass. In this paper, we performed fsLIBS on primary bone tumor, secondary tumor in bone, and normal bone. These tissues were excised from consenting patients and processed through the UC Davis Cancer Center Biorepository. For comparison, each tumor sample had a matched normal bone sample. fsLIBS was performed to characterize the spectral signatures of each tissue type. A minimum of 20 spectra were acquired for each sample. We did not detect significant differences between the fsLIBS spectra of secondary bone tumors and their matched normal bone samples, likely due to the heterogeneous nature of secondary bone tumors, with normal and cancerous tissue intermingling. However, we did observe an increase in the fsLIBS magnesium peak intensity relative to the calcium peak intensity for the primary bone tumor samples compared to the normal bone samples. These results show the potential of using femtosecond lasers for both ablation and a real-time feedback control system for treatment of primary bone tumors.

Background context Traditional reconstruction for burst fractures involves columnar support with posterior fixation at one or two levels cephalad/caudad; however, some surgeons choose to only stabilize the vertebral column. Purpose The aim was to distinguish biomechanical differences in stability between a burst fracture stabilized through a lateral approach using corpectomy spacers of different end plate sizes with and without integrated screws and with and without posterior fixation. Study design/Setting This was an in vitro biomechanical study assessing thoracolumbar burst fracture stabilization. Methods Six human spines (T11–L3) were tested on a six-degrees-of-freedom simulator enabling unconstrained range of motion (ROM) at ±6 N·m in flexion-extension (FE), lateral bending (LB), and axial rotation (AR) after a simulated burst fracture at L1. Expandable corpectomy spacers with/without integrated screws (Fi/F; FORTIFY Integrated/FORTIFY; Globus Medical, Inc., Audubon, PA, USA) were tested with different end plate sizes (21×23 mm, 22×40–50 mm). Posterior instrumentation (PI) via bilateral pedicle screws and rods was used one level above and one level below the burst fracture. Lateral plate (LP) fixation was tested. Devices were tested in the following order: intact; Fi 21×23 ; Fi 21×23 +PI; F 21×23 +PI+LP; F 21×23 +LP; F 22×40–50 +LP; F 22×40–50 +PI+LP; Fi 22×40–50 +PI; Fi 22×40–50 . Results In FE and AR, constructs without PI showed no significant difference (p 22×40–50 +LP showed a significant increase in stability relative to intact, but no other construct without PI reached significance. In FE and LB, circumferential constructs were significantly more stable than intact. In AR, no construct showed significant differences in motion when compared with the intact condition. Conclusions Constructs without posterior fixation were the least stable of all tested constructs. Circumferential fixation provided greater stability in FE and LB than lateral fixation and intact. Axial rotation showed no significant differences in any construct compared with the intact state.

Study Design Retrospective case series. Objective Diffuse idiopathic skeletal hyperostosis (DISH) or Forestier disease involves hyperostosis of the spinal column. Hyperostosis involving the anterior margin of the cervical vertebrae can cause dysphonia, dyspnea, and/or dysphagia. However, the natural history pertaining to the risk factors remain unknown. We present the surgical management of two cases of dysphagia secondary to cervical hyperostosis and discuss the etiology and management of DISH based on the literature review. Methods This is a retrospective review of two patients with DISH and anterior cervical osteophytes. We reviewed the preoperative and postoperative images and clinical history. Results Two patients underwent anterior cervical osteophytectomies due to severe dysphagia. At more than a year follow-up, both patients noted improvement in swallowing as well as their associated pain. Conclusion The surgical removal of cervical osteophytes can be highly successful in treating dysphagia if refractory to prolonged conservative therapy.

Using Titanium Mesh Cage and Anterior Cervical Plate for Cervical Corpectomies Spondylosis is the most common disease affecting the adult cervical spine. Controversy still exists over performing corpectomy versus discectomy for multilevel cervical disc disease. When the spondylosis leads to spinal cord compression beyond the disc space, removal of the cervical vertebrae may be necessary to achieve adequate decompression. Cervical corpectomy is a well-recognized treatment option for multilevel anterior compression of the cervical spinal cord.

Background: In previous reports, the patients are described to have transient symptoms from physiologic rotation or extension of the cervical spine, resulting from a cervical osteophyte compressing the vertebral artery and causing vertebral artery insufficiency, known as Bow Hunter syndrome. Methods: An 85-year-old female presented with new onset occipital headaches, nausea, vomiting and vertigo that were not precipitated by change in head position. Patient had bilateral cerebellar infracts. Patient underwent decompression and instrumented stabilization of the cervical spine from the posterior approach. Results: At one-year follow-up, patient remained stroke free with patent vertebral artery. Conclusion: To our knowledge, this is the first report of bilateral infraction from a vertebral artery insufficiency caused by cervical osteophytes without history of transient symptoms from movement of the head or neck, a variant of the Bow Hunter syndrome. Anterior versus posterior approach for vertebral artery insufficiency from osteophytic compression should be primarily based on location of the pathology and not the cervical level of involvement.

IntroductionAnterior cervical discectomy and fusion (ACDF) is one of the most common spinal procedures performed by spine surgeons to treat cervical degenerative disc disease. Use of anterior space...

IntroductionA novel ACDF (anterior cervical discectomy and fusion) construct possessing integrated screw and modular plate fixation (MPF) capabilities has been introduced in an effort to provide ve...

Although osteopathic manipulative treatment (OMT) is used to manage myriad conditions, there has been some hesitation regarding the safety of applying OMT to patients with intracranial injuries or elevated intracranial pressure (ICP).To assess the safety of two OMT techniques--pedal pump and thoracic pump--on ICP and cerebral perfusion pressure (CPP) in patients with traumatic brain injuries (Glasgow Coma Scale scoreor =8).We prospectively enrolled consecutive patients admitted to the intensive care unit (ICU) for traumatic brain injury. Patients between the ages of 18 and 75 years and with abnormal CT scans were included in the present study. Patients with baseline ICP values of 20 mm Hg or lower were assigned to group 1, and those with ICP levels greater than 20 mm Hg, group 2. Patients underwent continuous ICP and CPP monitoring, with ICP measured using a ventricular catheter and fiber optic device. Values of ICP and CPP were recorded at baseline, during application of the OMT techniques, and 5 minutes after the two OMT techniques were completed. Patients received up to three treatment cycles. Ventricular drains remained open (stopcock open) during OMT, allowing continued cerebral spinal fluid drainage, except for brief periodic closures (stopcock closed) every minute to register accurate ICP values. Statistical analysis was performed using a dependent t test with repeated measures.Twenty-four comatose patients, aged 18 to 69 years, received a total of 50 sessions of pedal pump and thoracic pump techniques. In group 1 patients, a slight decrease in ICP values (mean, -0.586 mm Hg) and an increase in CPP values (mean, 1.1613 mm Hg) was noted post-OMT. Patients in group 2 also had decreased mean ICP values (-1.20 mm Hg) and increased mean CPP values (2.2105 mm Hg). Changes were not statistically significant in either group.According to the present limited study, pedal pump and thoracic pump techniques may be used safely in patients with severe brain injuries.

We have reported that mice with an intracerebral (i.c.) malignant glioma or breast cancer treated with i.c. injection of allogeneic fibroblasts genetically engineered to secrete interleukin-2 (IL-2) survived longer than mice in various control groups. The goal of the present study was to determine the effectiveness of utilizing IL-2 secreting allogeneic fibroblasts as a protective treatment to prevent the development of an i.c. glioma or breast carcinoma. Using an intracranial microcannula system that we developed, the animals received weekly injections of the cellular vaccine prior to the introduction of tumor cells via the cannula. The results demonstrate a significant delay (P < 0.005) in the development of glioma in the animals pre-treated with either allogeneic non-secreting or IL-2-secreting fibroblasts prior to introduction of tumor cells. In addition, 50% of the animals pre-treated with IL-2 secreting allogeneic fibroblasts injected subsequently with Gl261 glioma cells did not develop a tumor, while all of the animals injected with glioma cells alone and 92% of those treated with non-secreting fibroblasts eventually died. The long-term survivors from the pre-treatment group were subsequently re-challenged with tumor and compared to naive controls. There was evidence that long-term immunity was established in the pre-treated animals, since there was a significant prolongation of survival (P < 0.01). In similar experiments using breast cancer cells, 62% of the animals pre-treated with non-secreting allogeneic fibroblasts and 75% of the animals pre-treated with allogeneic IL-2 secreting fibroblasts subsequently injected with SB-5b breast carcinoma cells did not develop tumors and had a significant prolongation of survival. These data suggest that i.c. injection of allogeneic IL-2 secreting fibroblasts are effective as a protective treatment in the prevention of the development of a brain tumor when the fibroblasts are introduced into the same site where the tumor is subsequently injected.