Intravertebral polymethylmethacrylate augmentation of anterior cervical discectomy fusion and plating in the setting of osteoporosis.

STUDY DESIGN: Case report and review of the literature. OBJECTIVE: The aim of this study was to describe a novel approach for anterior cervical fixation, which uses cement augmentation in a patient with osteoporosis. SUMMARY OF BACKGROUND DATA: Osteoporotic bone presents a challenge for the treating spine surgeon, and techniques to overcome the difficulty of cervical spine fixation in these patients are lacking. METHODS: A 75-year-old woman with osteoporosis presented with cervical myelopathy and was found to have multiple-level cervical stenosis and C3-4 degenerative instability. The patient underwent anterior cervical discectomy fusion and plating from C3-7, with vertebroplasty polymethylmethacrylate augmentation through the screw pilot holes. Because of the patient's grossly soft bone, she also underwent postoperative halo placement. RESULTS: No cement extravasation was observed. The halo was removed after 3 months. At 6 months follow-up, the patient had full resolution of her myelopathy. Imaging showed the cervical interbody fusions to be healed at all levels, with no screw pullout or graft subsidence. CONCLUSIONS: This represents the first comprehensive description of successful cement augmentation during anterior cervical discectomy fusion and plating in a patient with osteoporosis, accomplishing both an increase in screw pullout strength and a decreased likelihood of graft subsidence. With further study, this technique may represent a viable treatment option in patients with osteoporosis requiring cervical decompression and fusion.

Surgical treatment for intramedullary spinal cord melanocytomas.

Spinal meningeal melanocytomas are rare lesions that are histologically benign and can behave aggressively, with local infiltration. The authors present their experience with intramedullary spinal cord melanocytomas consisting of 3 cases, which represents the second largest series in the literature. A retrospective chart review was performed following identification of all spinal melanocytomas treated at the author's institution, based on information obtained from a neuropathology database. The charts were reviewed for patient demographics, surgical procedure, clinical outcome, and long-term tumor progression. Three patients were identified in whom spinal melanocytoma had been diagnosed between 1989 and 2006. The patients' ages were 37, 37, and 48 years, and the location of their tumor was C1-3, T9-10, and T-12, respectively. All 3 had complete resection with no adjuvant radiotherapy during follow-up periods of 16, 38, and 185 months, respectively. One patient demonstrated a recurrence 29 months after resection and the other 2 patients have demonstrated asymptomatic recurrences on imaging studies obtained at 16 and 38 months following resection. With these cases added to the available literature, the evidence strongly suggests that complete resection is the treatment of choice for spinal melanocytomas. Even with complete resection, recurrences are common and close follow-up is needed for the long term in these patients. Radiation therapy should be reserved for those cases in which complete resection is not possible or in which there is recurrence.

Augmentation of occipitocervical contoured rod fixation with C1-C2 transarticular screws.

BACKGROUND CONTEXT: The technique of occipitocervical fusion using a threaded contoured rod attached with sublaminar wires to the occiput and upper cervical vertebrae is widely used throughout the world and has been clinically proven to provide effective fixation of the destabilized spine. However, this system has some disadvantages in maintaining stability, especially at C1-C2 because of the large amount of axial rotation at this level. In some clinical situations such as fracture of the C1 lamina, C1 laminectomy, and excessively lordotic curvature, it is not always possible to wire C1 directly into the construct. In such cases, combination of other stabilization methods that include C1 indirectly can be used to achieve a reliable posterior internal fixation. PURPOSE: Primarily, to evaluate whether a contoured rod construct in which C1 is indirectly included using C1-C2 transarticular screws is biomechanically equivalent to a standard, fully wired contoured rod construct. Secondarily, to evaluate the biomechanical benefit of adding C1-C2 transarticular screws to a fully wired contoured rod construct. STUDY DESIGN: Repeated-measures nondestructive in vitro biomechanical testing of destabilized cadaveric human occipitocervical spine specimens. METHODS: Six human cadaveric specimens from the occiput to C3 were studied. Angular and linear displacement data were recorded while nonconstraining nondestructive loads were applied. Three methods of fixation were tested: contoured rod incorporating C1 with and without transarticular screws and contoured rod with transarticular screws without incorporating C1. RESULTS: All three constructs reduced motion to well within normal range. In contoured rod constructs with C1 wired, addition of transarticular screws slightly but significantly improved stability. In constructs with transarticular screws, incorporation of C1 into the contoured rod wiring did not improve stability significantly. CONCLUSIONS: Adding C1-C2 transarticular screws to a wired contoured rod construct where C1 is included only slightly improves stability. As the absolute reduction in motion from adding transarticular screws is small (<1 degree), it is doubtful whether any enhanced fusion from this additional procedure outweighs the surgical risks. However, transarticular screws provide an effective alternate method to fixate C1 when the posterior arch of C1 is absent or has been fractured.

Biomechanical comparison of two-level cervical locking posterior screw/rod and hook/rod techniques.

BACKGROUND CONTEXT: Locking posterior instrumentation in the cervical spine can be attached using 1) pedicle screws, 2) lateral mass screws, or 3) laminar hooks. This order of options is in order of decreasing technical difficulty and decreasing depth of fixation, and is thought to be in order of decreasing stability. PURPOSE: We sought to determine whether substantially different biomechanical stability can be achieved in a two-level construct using pedicle screws, lateral mass screws, or laminar hooks. Secondarily, we sought to quantify the differential and additional stability provided by an anterior plate. STUDY DESIGN: In vitro biomechanical flexibility experiment comparing three different posterior constructs for stabilizing the cervical spine after three-column injury. METHODS: Twenty-one human cadaveric cervical spines were divided into three groups. Group 1 received lateral mass screws at C5 and C6 and pedicle screws at C7; Group 2 received lateral mass screws at C5 and C6 and laminar hooks at C7; Group 3 received pedicle screws at C5, C6, and C7. Specimens were nondestructively tested intact, after a three-column two-level injury, after posterior C5-C7 rod fixation, after two-level discectomy and anterior plating, and after removing posterior fixation. Angular motion was recorded during flexion, extension, lateral bending, and axial rotation. Posterior hardware was subsequently failed by dorsal loading. RESULTS: Laminar hooks performed well in resisting flexion and extension but were less effective in resisting lateral bending and axial rotation, allowing greater range of motion (ROM) than screw constructs and allowing a significantly greater percentage of the two-level ROM to occur across the hook level than the screw level (p<.03). Adding an anterior plate significantly improved stability in all three groups. With combined hardware, Group 3 resisted axial rotation significantly worse than the other groups. Posterior instrumentation resisted lateral bending significantly better than anterior plating in all groups (p<.04) and resisted flexion and axial rotation significantly better than anterior plating in most cases. Standard deviation of the ROM was greater with anterior than with posterior fixation. There was no significant difference among groups in resistance to failure (p=.74). CONCLUSIONS: Individual pedicle screws are known to outperform lateral mass screws in terms of pullout resistance, but they offered no apparent advantage in terms of construct stability or failure of whole constructs. Larger standard deviations in anterior fixation imply more variability in the quality of fixation. In most loading modes, laminar hooks provided similar stability to lateral mass screws or pedicle screws; caudal laminar hooks are therefore an acceptable alternative posteriorly. Posterior two-level fixation is less variable and slightly more stable than anterior fixation. Combined instrumentation is significantly more stable than either anterior or posterior alone.

Survivors of occipitoatlantal dislocation injuries: imaging and clinical correlates.

OBJECT: Although rare, traumatic occipitoatlantal dislocation (OAD) injuries are associated with a high mortality rate. The authors evaluated the imaging and clinical factors that determined treatment and were predictive of outcomes, respectively, in survivors of this injury. METHODS: The medical records and imaging studies obtained in 33 patients with OAD were reviewed retrospectively. Clinical factors that predicted outcomes, especially neurological injury at presentation and imaging findings, were evaluated. The most sensitive method for the diagnosis of OAD was the measurement of basion axial-basion dens interval on computed tomography (CT) scanning. Five patients with severe traumatic brain injuries (TBIs) were not treated and subsequently died. Of the 28 patients in whom treatment was performed, 23 underwent fusion and five were fitted with an external orthosis. Abnormal findings of the occipitoatlantal ligaments on magnetic resonance (MR) imaging, associated with no or questionable abnormalities on CT scanning, provided the rationale for nonoperative treatment. Of the 28 patients treated for their injuries, perioperative death occurred in five, three of whom had presented with severe neurological injuries. The mortality rate was highest in patients with a TBI at presentation. The mortality rate was lower in patients presenting with a spinal cord injury, but in this group there was a higher rate of persistent neurological deficits. CONCLUSIONS: The spines in patients with CT-documented OAD are most likely unstable and need surgical fixation. In patients for whom CT findings are normal and MR imaging findings suggest marginal abnormalities, nonoperative treatment should be considered. The best predictors of outcome were severe brain or upper cervical injuries at initial presentation.

Complete Spondylectomy Using Orthogonal Spinal Fixation and Combined Anterior and Posterior Approaches for Thoracolumbar Spinal Reconstruction: Technical Nuances and Clinical Results.

STUDY DESIGN: Retrospective chart review. OBJECTIVE: To determine the long-term efficacy of 2-stage total en bloc spondylectomy (TES). SUMMARY OF BACKGROUND DATA: TES is a well-described technique to achieve tumor-free margins, but it is a highly destabilizing procedure that necessitates spinal reconstruction. A 2-stage anterior/posterior approach for tumor resection and instrumentation has been shown to be biomechanically superior to the single-stage approach in achieving rigid fixation, but few clinical studies with long-term outcomes exist. METHODS: A retrospective review was performed on patients undergoing a 2-stage TES for a spinal tumor between 1999 and 2011. Results were compared with those from a literature review of case series, with a minimum of 2-year follow-up, reporting on a single-stage posterior-only approach for TES. RESULTS: Seven patients were identified (average follow-up 52.7 mo). Tumor location ranged from T1 to L3 with the following pathologies: metastasis (n=3), hemangioma (n=1), leiomyosarcoma (n=1), giant cell tumor (n=1), and chordoma (n=1). There were no significant surgical complications. All 7 patients had intact spinal fixation. There were no failures of the orthogonal fixation (pedicle screws or anterior fixation). The average modified Rankin Scale scores improved from 2.7 preoperatively to 0.7 at last follow-up. None of the patients in our series suffered local disease recurrence at last follow-up or suffered neurological deterioration. These results were comparable with those noted in the literature review of posterior-only approach, where 12% of patients experienced instrument failure. CONCLUSIONS: TES is a highly destabilizing procedure requiring reconstruction resistant to large multiplanar translational and torsional loads. A 2-stage approach utilizing orthogonal vertebral body screws perpendicular to pedicle screws is a safe and effective surgical treatment strategy. Orthogonal spinal fixation may lower the incidence of instrumentation failure associated with complete spondylectomy and appears to be comparable with a single-stage procedure. However, larger prospective series are necessary to assess the efficacy of this approach versus traditional means.

Repair of V2 Vertebral Artery Injuries Sustained During Anterior Cervical Diskectomy.

BACKGROUND: The V2 segment of the vertebral artery (VA) typically runs through the transverse foramen of C2-C6. V2 injury may occur during anterior approaches to the cervical spine and can cause significant morbidity. We describe landmarks and microsurgical V2 repair techniques through the standard anterolateral cervical diskectomy approach. METHODS: Five silicone-injected cadaveric heads (necks-C7) were dissected bilaterally. An anterolateral approach with C3-4, C4-5, and C5-6 diskectomies and an ipsilateral VA injury were simulated. VA approach and repair were performed using microdissection techniques. Landmarks to the VA were identified, and distances from landmarks to the VA were measured in horizontal and vertical planes. Operative photographs of stepwise approach and repair techniques were processed for stereoscopic illustration. An illustrative case describes microsurgery to successfully repair an inadvertent VA injury during a C3-C6 diskectomy and fusion procedure. RESULTS: The anatomic landmarks delineated were the intervertebral disk, uncinate apices, and anterior tubercles of C4-C6 transverse processes. After temporary hemostasis with packing, VA exposure and repair included dissection of the longus colli muscle, removal of the anterior root of the transverse processes above and below the injury level, intertransversarii muscle removal, vertebral plexus opening, VA handling, and microsuturing. In 30 dissected cadaver intertransverse intervals, 13 medial, 7 lateral, and 3 anterior branches of the V2 were encountered at C3-C6 levels. CONCLUSION: Familiarity with relevant vascular surgical anatomy allows neurosurgeons to be prepared in cases of VA injury and may facilitate repair when the VA is injured during anterior cervical spine surgery.

Retroperitoneal approach for lumbar interbody fusion with anterolateral instrumentation for treatment of spondylolisthesis and degenerative foraminal stenosis.

BACKGROUND: An alternative approach for the treatment of the degenerative or unstable lumbar spine using retroperitoneal lateral LIF with anterolateral screw-plate or screw-rod fixation is introduced. Special attention is given to application of this procedure in patients who have undergone prior lumbar surgery. METHODS: Between 1998 and 2001, 14 patients underwent lateral LIF with anterolateral instrumentation to treat degenerative foraminal stenosis or spondylolisthesis. Eleven patients (79%) had undergone prior posterior lumbar surgery, 7 of whom were also fused at that time. All patients first presented with mechanical back pain, radicular pain, or both. The mean follow-up was 21 months (range, 8 to 36 months). RESULTS: Radicular pain and mechanical back pain significantly improved in 71% and 54% of patients, respectively. Of the 9 patients with preoperative neurological deficits, 7 were intact or had improved at their follow-up examination. One patient developed postoperative radiculopathy contralateral to his original symptoms. Radiography confirmed good positioning of the hardware and evidence of fusion in all 14 patients. No major complications occurred. CONCLUSIONS: Retroperitoneal lateral LIF with anterolateral instrumentation is an attractive alternative for the treatment of the degenerative or unstable lumbar spine in the absence of significant spinal stenosis. This approach is particularly useful for treating spondylolisthesis or degenerative foraminal stenosis in the postoperative lumbar spine.

Distraction injury to thoracic spine treated with thoracoscopic dual-rod fixation.

BACKGROUND CONTEXT: Thoracic hyperextension fracture-dislocation is a rare pattern of traumatic spinal injury, typically associated with gross spinal instability and severe neurological deficit. These extremely unstable injuries require internal fixation despite their potentially benign clinical presentation. PURPOSE: We present a patient with a thoracic distraction injury who remained neurologically intact. METHODS: The patient underwent thoracoscopic reduction and anterior fixation of the thoracic spine using a paired screw-rod construct. RESULTS: Postoperatively, the patient remained neurologically intact and had no complications related to his thoracic fixation and fusion. Follow-up radiographs showed maintenance of thoracic alignment and bony fusion. CONCLUSIONS: The endoscopic approach to the anterior thoracic spine was an excellent treatment option for this thoracic distraction injury.

Durectomy and reconstruction for the treatment of a recurrent spinal meningioma. Case report.

The management of spinal meningiomas with extensive involvement of the dura mater is controversial. The principal difficulty in performing a resection is the potential for complications associated with this approach. The authors present the case of a pregnant 35-year-old woman in whom bilateral lower-extremity numbness, weakness, gait ataxia, and myelopathy developed. Magnetic resonance imaging showed a recurrent thoracic meningioma with extensive infiltration of the dura mater. Durectomy, complete resection, and reconstruction were performed. The patient has not experienced a recurrence 21 months after her treatment. This case illustrates that thoracic spinal meningiomas with extensive dural involvement can be resected safely with a complete durectomy. The novel dural reconstruction involving the implantation of a fascia lata and bovine pericardium allograft is an effective way to reconstruct the dura to create an adequate barrier to cerebrospinal fluid.

Complications of halo fixation in the elderly.

OBJECT: The risk factors of halo fixation in elderly patients have never been analyzed. The authors therefore retrospectively reviewed data obtained in the treatment of such cases. METHODS: A discharge database was searched for patients 70 years of age or older who had undergone placement of a halo device. In a search of cases managed between April 1999 and February 2005, data pertaining to 53 patients (mean age 79.9 years [range 70-97 years]) met these criteria. Forty-one patients were treated for traumatic injuries. Ten patients had deficits ranging from radiculopathy to quadriparesis, and 43 had no neurological deficit. Adequate follow-up material was available in 42 patients (mean treatment duration 91 days). Halo immobilization was the only treatment in 21 patients, and adjunctive surgical fixation was undertaken in the other 21 patients. There were 31 complications in 22 patients: respiratory distress in four patients, dysphagia in six, and pin-related complications in 10. Eight patients died; in two of these cases, the cause of death was clearly unrelated to the halo brace. The other six patients died of respiratory failure and cardiovascular collapse (perioperative mortality rate 14%). Three patients who died had sustained acute trauma and three had undergone surgical stabilization. CONCLUSIONS: External halo fixation can be used safely to treat cervical instability in elderly patients. The high complication rate in this population may reflect the significant incidence of underlying disease processes.

A biomechanical comparison of three anterior thoracolumbar implants after corpectomy: are two screws better than one?

OBJECT: A flexibility experiment using human cadaveric thoracic spine specimens was performed to determine biomechanical differences among thoracolumbar two-screw plate, single-screw plate, and dual-rod systems. A secondary goal was to investigate differences in the ability of the systems to stabilize the spine after a one- or two-level corpectomy. METHODS: The authors evaluated 21 cadaveric spines implanted with a titanium mesh cage and three types of anterior thoracolumbar supplementary instrumentation after one-level thoracic corpectomies. Pure moments were applied quasistatically while three-dimensional motion was measured optoelectronically. The lax zone, stiff zone, and range of motion (ROM) were measured during flexion, extension, left and right lateral bending, and left and right axial rotation. Corpectomies were expanded to two levels, and testing was repeated with longer hardware. Biomechanical testing showed that the single-bolt plate system was no different from the dual-rod system with two screws in limiting ROM. The single-bolt plate system performed slightly better than the two-screw plate system. Across the same two levels, there was an average of 19% more motion after a two-level corpectomy than after a one-level corpectomy. In general, however, the difference across the different loading modes was insignificant. CONCLUSIONS: Biomechanically, the single-screw plate system is equivalent to a two-screw dual-rod and a two-screw plate system. All three systems performed similarly in stabilizing the spine after one- or two-level corpectomies.

Indications and Techniques for Spinal Instrumentation in Thoracic Disk Surgery.

STUDY DESIGN: Retrospective case series. OBJECTIVE: To identify the indications, techniques, and outcomes for instrumented fusion during thoracic discectomy. SUMMARY OF BACKGROUND DATA: Thoracic discectomy may require extensive bone removal to avoid spinal cord manipulation, but the indications and techniques for instrumented fusion during thoracic discectomy remain poorly delineated. METHODS: The authors identified 220 consecutive patients who underwent thoracic discectomy between 1992 and 2012. Clinical and radiographic variables were compared between patients who underwent instrumented fusion and patients without instrumentation, and among surgical approaches utilized for discectomy. RESULTS: Patient age for the entire cohort averaged 49±13.01 years, and mean clinical follow-up was 45 months (range, 1-218 mo). Patients underwent 226 thoracic discectomy procedures, including 48 thoracotomy, 136 thoracoscopy, and 42 posterolateral approaches. Seventy-eight patients required instrumented fusion and, compared with patients without instrumentation, were more likely to present with myelopathy (P<0.0001) and harbor giant (P=0.0012), calcified (P=0.019), or transdural (P=0.0004) herniated disks. Surgery with instrumentation resulted in greater blood loss (P<0.0001), longer hospital stay (P<0.0001), and a higher complication rate (22% vs. 9.9%), yet patients in both cohorts had similar rates of symptom resolution postoperatively. Of the patients who underwent thoracic discectomy without instrumentation, 3 (2.1%) developed delayed deformity or instability and required subsequent surgery for fixation and fusion at an average 6.3 months postoperatively (range, 4-8 mo). Patients who underwent instrumented fusion exhibited no nonunions or delayed deformity. CONCLUSIONS: Thoracic discectomy without fixation is a reasonable clinical option in carefully selected patients, but instrumented fusion is safe and effective in other patients. Indications for fixation and fusion are thus proposed.

Effects of Anterior Plating on Clinical Outcomes of Anterior Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective review. OBJECTIVE: To compare surgical outcomes of patients who have undergone anterior lumbar interbody fusion (ALIF) with and without plating. SUMMARY OF BACKGROUND DATA: In biomechanical testing, ALIF constructs supplemented with plating (ALIFP) reduce range of motion and increase construct stiffness compared with ALIF alone. However, whether ALIFP constructs translate into improved clinical outcomes over ALIF alone is unknown. METHODS: From 2004 through 2010, 231 patients underwent ALIF with (146) or without (85) plating. Eight patients lost to follow up were excluded from final evaluation. Patients' records were evaluated retrospectively for demographics, complications, and outcomes. RESULTS: At a mean follow-up of 13.7 months (range, 1-108 mo), the mean Economic, Functional, and Total Prolo scores for ALIF patients were 4.23, 3.63, and 7.87, respectively. The mean Oswestry Disability Index (ODI) was 24%. At a mean follow-up of 11.2 months (range, 1-93 mo), the mean Economic, Functional, and Total Prolo scores for ALIFP patients were 4.28, 3.67, and 7.95, respectively. The mean ODI was 22.9%. There was no significant difference between rate of complications or Prolo scores or ODI between the 2 groups (t test). Neither diabetes, hypertension, smoking, sex, nor age older than 55 years was significantly related to whether patients had higher Prolo scores with or without plating. Patients with a normal body mass index and ALIF had significantly better Prolo Economic scores and total scores than patients with a normal body mass index and ALIFP (P=0.04 and 0.02, independent samples t test). Patients were also stratified by surgical indication for surgery, and there was no significant difference in Prolo scores or ODI for patients who underwent ALIF alone versus ALIFP. CONCLUSIONS: Even when stratified by indication for surgery, anterior plating does not seem to improve Prolo scores or ODI, suggesting that not all patients undergoing ALIF require plating.

The Influence of Common Medical Conditions on the Outcome of Anterior Lumbar Interbody Fusion.

STUDY DESIGN: The authors retrospectively reviewed a consecutive series of 231 patients with anterior lumbar interbody fusion (ALIF). OBJECTIVE: To determine the correlations among common medical conditions, demographics, and the natural history of lumbar surgery with outcomes of ALIF. SUMMARY OF BACKGROUND DATA: Multiple spinal disorders are treated with ALIF with excellent success rates. Nonetheless, adverse outcomes and complications related to patients' overall demographics, comorbidities, or cigarette smoking have been reported. METHODS: The age, sex, body mass index (BMI), comorbidities, history of smoking or previous lumbar surgery, operative parameters, and complications of 231 patients who underwent ALIF were analyzed. Regression analyses of all variables with complications and surgical outcomes based on total Prolo scores were performed. Two models predicting Prolo outcome score were generated. The first model used BMI and sex interaction, whereas the second model used sex, level of surgery, presence of diabetes mellitus, and BMI as variables. RESULTS: At follow-up, the rate of successful fusion was 99%. The overall complication rate was 13.8%, 1.8% of which occurred intraoperatively and 12% during follow-up. The incidence of complications failed to correlate with demographics, comorbidities, smoking, or previous lumbar surgery (P>0.5). ALIF at T12-L4 was the only factor significantly associated with poor patient outcomes (P=0.024). Both models successfully predicted outcome (P=0.05), although the second model did so only for males. CONCLUSIONS: Surgical level of ALIF correlated with poor patient outcomes as measured by Prolo functional scale. BMI emerged as a significant predictor of Prolo total score. Both multivariate models also successfully predicted outcomes. Surgical or follow-up complications were not associated with patients' preoperative status.

Atlantooccipital transarticular screw fixation for the treatment of traumatic occipitoatlantal dislocation. Technical note.

The authors describe a new technique of internal atlantooccipital screw fixation involving posterior wiring and fusion for the treatment of traumatic atlantooccipital dislocation, which was performed in a 17-year-old male patient involved in a motor vehicle accident and who suffered from atlantooccipital dislocation without neurological injury. At the 6-month follow-up examination, the patient was neurologically intact with a solid occipitocervical fusion and full range of motion of the neck.

Surgical management of giant herniated thoracic discs: analysis of 20 cases.

OBJECT: The authors evaluated the clinical and surgical outcomes obtained in patients with giant herniated thoracic discs (HTDs), defined as occupying more than 40% of the spinal canal. Surgery-related considerations and functional outcomes in patients with small- and medium-sized HTDs were compared. METHODS: The authors reviewed 140 cases of surgically treated HTDs, 20 (14%) of which were giant. Before and after surgery, all patients underwent computerized tomography myelography, magnetic resonance imaging, or both. Functional outcomes were assessed using the Frankel grading system preoperatively, immediately after surgery, and at long-term follow-up examination. The results observed in patients with giant HTDs were compared with those with small- and medium-sized HTDs. The mean overall follow-up period was 2.6 years. Sixty-six patients (47%) presented with myelopathy, including 19 (95%) with a giant HTD. Of the latter, 16 (80%) underwent anterior, eight thoracoscopic, and eight open thoracotomy approaches. Four patients (20%) with laterally oriented giant HTDs within the spinal canal underwent surgery via a posterolateral approach. Based on analysis of long-term follow-up data, 53% of patients with giant HTDs improved neurologically by one Frankel grade. Progression of myelopathy was arrested in 42%, and in 5% the Frankel grade worsened by one. In patients with small- and medium-sized HTDs, the Frankel grade improved by one in 77%, stabilized in 23%, and worsened in 0%. Patients with giant HTDs who underwent thoracoscopic surgery had worse short- and long-term functional outcomes than those in whom open thoracotomy was performed. CONCLUSIONS: Patients with giant HTDs presented more frequently with myelopathy and experienced worse functional outcomes than those with smaller HTDs. Based on their experience, the authors recommend open thoracotomy rather than thoracoscopy for the treatment of midline giant HTDs.

Use of dual transarticular screws to fixate simultaneous occipitoatlantal and atlantoaxial dislocations.

Occipitoatlantal dislocation and atlantoaxial vertical distraction are caused by similar mechanisms, and few individuals survive these injuries. It is hypothesized that the injurious vertical force manifests as a traumatic lesion at different levels of the same ligamentous complex. The authors report the cases of two patients who presented with this combined lesion, describe surgical alternatives for stabilization, and introduce a new technique that combines the use of transarticular screws in a "dual" construct, without involving the unaffected spine.

Surgical and clinical efficacy of sacroiliac joint fusion: a systematic review of the literature.

OBJECT: The sacroiliac joint (SIJ) and surgical intervention for treating SIJ pain or dysfunction has been a topic of much debate in recent years. There has been a resurgence in the implication of this joint as the pain generator for many patients experiencing low-back pain, and new surgical methods are gaining popularity within both the orthopedic and neurosurgical fields. There is no universally accepted gold standard for diagnosing or surgically treating SIJ pain. The authors systematically reviewed studies on SIJ fusion in the neurosurgical and orthopedic literature to investigate whether sufficient evidence exists to support its use. METHODS: A literature search was performed using MEDLINE, Google Scholar, and OvidSP-Wolters Kluwer Health for all articles regarding SIJ fusion published from 2000 to 2014. Original, peer-reviewed, prospective or retrospective scientific papers with at least 2 patients were included in the study. Exclusion criteria included follow-up shorter than 1-year, nonsurgical treatment, inadequate clinical data as determined by 2 independent reviewers, non-English manuscripts, and nonhuman subjects. RESULTS: A total of 16 peer-reviewed journal articles met the inclusion criteria: 5 consecutive case series, 8 retrospective studies, and 3 prospective cohort studies. A total of 430 patients were included, of whom 131 underwent open surgery and 299 underwent minimally invasive surgery (MIS) for SIJ fusion. The mean duration of follow-up was 60 months for open surgery and 21 months for MIS. SIJ degeneration/arthrosis was the most common pathology among patients undergoing surgical intervention (present in 257 patients [59.8%]), followed by SIJ dysfunction (79 [18.4%]), postpartum instability (31 [7.2%]), posttraumatic (28 [6.5%]), idiopathic (25 [5.8%]), pathological fractures (6 [1.4%]), and HLA-B27+/rheumatoid arthritis (4 [0.9%]). Radiographically confirmed fusion rates were 20%-90% for open surgery and 13%-100% for MIS. Rates of excellent satisfaction, determined by pain reduction, function, and quality of life, ranged from 18% to 100% with a mean of 54% in open surgical cases. For MIS patients, excellent outcome, judged by patients' stated satisfaction with the surgery, ranged from 56% to 100% (mean 84%). The reoperation rate after open surgery ranged from 0% to 65% (mean 15%). Reoperation rate after MIS ranged from 0% to 17% (mean 6%). Major complication rates ranged from 5% to 20%, with 1 study that addressed safety reporting a 56% adverse event rate. CONCLUSIONS: Surgical intervention for SIJ pain is beneficial in a subset of patients. However, with the difficulty in accurate diagnosis and evidence for the efficacy of SIJ fusion itself lacking, serious consideration of the cause of pain and alternative treatments should be given before performing the operation.

Surgical efficacy of minimally invasive thoracic discectomy.

We aimed to determine the clinical indications and surgical outcomes for thoracoscopic discectomy. Thoracic disc disease is a rare degenerative process. Thoracoscopic approaches serve to minimize tissue injury during the approach, but critics argue that this comes at the cost of surgical efficacy. Current reports in the literature are limited to small institutional patient series. We systematically identified all English language articles on thoracoscopic discectomy with at least two patients, published from 1994 to 2013 on MEDLINE, Science Direct, and Google Scholar. We analyzed 12 articles that met the inclusion criteria, five prospective and seven retrospective studies comprising 545 surgical patients. The overall complication rate was 24% (n=129), with reported complications ranging from intercostal neuralgia (6.1%), atelectasis (2.8%), and pleural effusion (2.6%), to more severe complications such as pneumonia (0.8%), pneumothorax (1.3%), and venous thrombosis (0.2%). The average reported postoperative follow-up was 20.5 months. Complete resolution of symptoms was reported in 79% of patients, improvement with residual symptoms in 10.2%, no change in 9.6%, and worsening in 1.2%. The minimally invasive endoscopic approaches to the thoracic spine among selected patients demonstrate excellent clinical efficacy and acceptable complication rates, comparable to the open approaches. Disc herniations confined to a single level, with small or no calcifications, are ideal for such an approach, whereas patients with calcified discs adherent to the dura would benefit from an open approach.