The Effect of C2 Muscular Exposure Technique on Radiographic and Clinical Outcomes After C2-T2 Posterior Cervical Fusion.

STUDY DESIGN: Retrospective cohort analysis. OBJECTIVE: To determine whether the C2 exposure technique was a predictor of change in cervical alignment and patient-reported outcomes measures (PROMs) after posterior cervical decompression and fusion (PCDF) for degenerative indications. BACKGROUND: In PCDF handling of the C2 posterior paraspinal musculature during the operative approach varies by surgeon technique. To date, no studies have investigated whether maintenance of the upper cervical semispinalis cervicis attachments as compared with complete reflection of upper cervical paraspinal musculature from the posterior bony elements is associated with superior radiographic and clinical outcomes after PCDF. PATIENTS AND METHODS: All adult patients who underwent C2-T2 PCDF for myelopathy or myeloradiculopathy at multi-institutional academic centers between 2013 and 2020 were retrospectively identified. Patients were dichotomized by the C2 exposure technique into semispinalis preservation or midline muscular reflection groups. Preoperative and short and long-term postoperative radiographic outcomes (upper cervical alignment, global alignment, and fusion status) and PROMs (Visual Analog Scale-Neck, Neck Disability Index, and Short Form-12) were collected. Univariate analysis compared patient factors, radiographic measures, and PROMs across C2 exposure groups. RESULTS: A total of 129 patients met the inclusion/exclusion criteria (73 muscle preservation and 56 muscle reflection). Patients in the muscular preservation group were on average younger (P= 0.005) and more likely to have bone morphogenic protein (P< 0.001) and C2 pars screws (P= 0.006) used during surgery. Preoperative to postoperative changes in C2 slope, C2 tilt, C2-C3 segmental lordosis, C2-C3 listhesis, C0-C2 Cobb angle, proximal junctional kyphosis, ADI, C1 lamina-occiput distance, C2 sagittal vertical axis, C2-C7 lordosis, and PROMs at all follow-up intervals did not vary significantly by C2 exposure technique. Likewise, there were no significant differences in fusion status, C2-C3 pseudoarthrosis, C2 screw loosening, and complication and revision rates between C2 exposure groups. CONCLUSIONS: Preservation of C2 semispinalis attachments versus muscular reflection did not significantly impact cervical alignment, clinical outcomes, or proximal junction complications in long-segment PCDF. LEVEL OF EVIDENCE: Level III.

SPECT-CT as a Predictor of Pain Generators in Patients Undergoing Intra-Articular Injections for Chronic Neck and Back Pain.

BACKGROUND: The ability to accurately predict pain generators for chronic neck and back pain remains elusive. OBJECTIVE: We evaluated whether injections targeted at foci with uptake on single-photon emission computerized tomography-computed tomography (SPECT-CT) were associated with improved outcomes in patients with chronic neck and back pain. METHODS: A retrospective review was completed on patients undergoing SPECT-CT for chronic neck and back pain between 2016 and 2020 at a tertiary academic center. Patients' records were reviewed for demographic, clinical, imaging, and outcomes data. Only those patients who had facet injections after SPECT-CT were included in this evaluation. Patients undergoing injections targeted at foci of abnormal radiotracer uptake were compared with patients without uptake concerning immediate positive response, visual analog scale, and the need for additional injection or surgery at the target level. RESULTS: A total of 2849 patients were evaluated with a SPECT-CT for chronic neck and back pain. Of those, 340 (11.9%) patients received facet joint injections after SPECT-CT. A propensity score regression analysis adjusted for age, gender, body mass index, hypertension, multiple target injections, and injection location showed uptake targeted injections not being associated with an improved immediate positive response (odds ratio: 0.64; 95% confidence interval: 0.34-1.21; P = 0.172). In patients with a failed facet injection preceding SPECT-CT, adding SPECT-CT to guide facet injections was associated with a decrease in visual analog scale pain scores 2 weeks after injection (P = 0.018), particularly when changes were made to the facets being targeted (P = 0.010). CONCLUSION: This study suggests that there is benefit with SPECT-CT specially to guide facet injections after failed prior facet injections.

Robotic-Assisted vs Nonrobotic-Assisted Minimally Invasive Transforaminal Lumbar Interbody Fusion: A Cost-Utility Analysis.

BACKGROUND: Management of degenerative disease of the spine has evolved to favor minimally invasive techniques, including nonrobotic-assisted and robotic-assisted minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). Value-based spending is being increasingly implemented to control rising costs in the US healthcare system. With an aging population, it is fundamental to understand which procedure(s) may be most cost-effective. OBJECTIVE: To compare robotic and nonrobotic MIS-TLIF through a cost-utility analysis. METHODS: We considered direct medical costs related to surgical intervention and to the hospital stay, as well as 1-yr utilities. We estimated costs by assessing all cases involving adults undergoing robotic surgery at a single institution and an equal number of patients undergoing nonrobotic surgery, matched by demographic and clinical characteristics. We adopted a willingness to pay of $50 000/quality-adjusted life year (QALY). Uncertainty was addressed by deterministic and probabilistic sensitivity analyses. RESULTS: Costs were estimated based on a total of 76 patients, including 38 undergoing robot-assisted and 38 matched patients undergoing nonrobot MIS-TLIF. Using point estimates, robotic surgery was projected to cost $21 546.80 and to be associated with 0.68 QALY, and nonrobotic surgery was projected to cost $22 398.98 and to be associated with 0.67 QALY. Robotic surgery was found to be more cost-effective strategy, with cost-effectiveness being sensitive operating room/materials and room costs. Probabilistic sensitivity analysis identified robotic surgery as cost-effective in 63% of simulations. CONCLUSION: Our results suggest that at a willingness to pay of $50 000/QALY, robotic-assisted MIS-TLIF was cost-effective in 63% of simulations. Cost-effectiveness depends on operating room and room (admission) costs, with potentially different results under distinct neurosurgical practices.

Minimally Invasive Transforaminal Lumbar Interbody Fusion: Cost of a Surgeon's Learning Curve.

BACKGROUND: Minimally invasive transforaminal interbody fusion has become an increasingly common approach in adult degenerative spine disease but is associated with a steep learning curve. We sought to evaluate the impact of the learning experience on mean procedure time and mean cost associated with each procedure. METHODS: We studied the first 100 consecutive minimally invasive transforaminal interbody fusion procedures of a single surgeon. We performed multivariable linear regression models, modeling operating time, and costs in function of the procedure order adjusted for patients' age, sex, and number of surgical levels. The number of procedures necessary to attain proficiency was determined through a k-means cluster analysis. Finally, the total excess operative time and total excess cost until obtaining proficiency was evaluated. RESULTS: Procedure order was found to impact procedure time and mean costs, with each successive case being associated with progressively less procedure time and cost. On average, each successive case was associated with a reduction in procedure time of 0.97 minutes (95% confidence interval 0.54-1.40; P < 0.001) and an average adjusted reduction in overall costs of $82.75 (95% confidence interval $35.93-129.57; P < 0.001). An estimated 58 procedures were needed to attain proficiency, translating into an excess procedure time of 2604.2 minutes (average of 45 minutes per case), overall costs associated with the learning experience of $226,563.8 (average of $3974.80 per case), and excess surgical cost of $125,836.6 (average of $2207.66 per case). CONCLUSIONS: Successive cases were associated with progressively less procedure time and mean overall and surgical costs, until a proficiency threshold was attained.

Initial Results of Precision Treatment of Postoperative Cerebrospinal Fluid Leak with Ultrasound-Guided Epidural Blood Patch.

BACKGROUND: Incidental durotomy, a known complication of spinal surgery, can lead to persistent cerebrospinal fluid leak and pseudomeningocele if unrecognized or incompletely repaired. We describe the use of ultrasound to visualize the site of durotomy, observe the aspiration of the pseudomeningocele, and guide the precise application of an ultrasound-guided epidural blood patch (US-EBP), under direct visualization in real time. METHODS: A retrospective review was performed to determine demographic, procedural, and outcome characteristics for patients who underwent US-EBP for symptomatic postoperative pseudomeningocele. RESULTS: Overall, 48 patients who underwent 49 unique episodes of care were included. The average age and body mass index were 60.5 (±12.6) years and 27.8 (±4.50) kg/m2, respectively. The most frequent index operation was laminectomy (24.5%), and 36.7% of surgeries were revision operations. Durotomy was intended or recognized in 73.4% of cases, and the median time from surgery to symptom development was 7 (interquartile range 4-16) days. A total of 61 US-EBPs were performed, with 51.0% of patients experiencing resolution of their symptoms after the first US-EBP. An additional 20.4% were successful with multiple US-EBP attempts. Complications occurred in 14.3% of cases, and the median clinical follow-up was 4.3 (interquartile range 2.4-14.5) months. CONCLUSIONS: This manuscript represents the largest series in the literature describing US-EBP for the treatment of postoperative pseudomeningocele. The success rate suggests that routine utilization of US-guided EBP may allow for targeted treatment of pseudomeningoceles, without the prolonged hospitalization associated with lumbar drains or the risks of general anesthesia and impaired wound healing associated with surgical revision.

Results of surgical resection of carotid body tumors: A twenty-year experience.

This study examines whether surgical resection of carotid body tumors (CBTs) is acceptable in light of potential significant neurologic complications. This IRB-approved retrospective study analyzed data from 24 patients undergoing surgical treatment for CBTs between April 1998 and April 2017 at Mayo Clinic (Florida campus only). For patients who underwent multiple CBT resections, only data from the first surgery was used in this analysis. CBT resection occurred in 24 patients with the following demographics: fourteen patients (58.3%) were female, median age was 56.5 years, median BMI was 29. A prior history of neoplasm was found in ten patients (41.7%). A known family history of paraganglioma was present in five patients (20.8%). Two patients were positive for succinate dehydrogenase mutation (8.3%). Multiple paragangliomas were present in seven patients (29.2%). There was nerve sacrifice in three patients (12.5%) during resection. Carotid artery reconstruction and patch angioplasty occurred in one patient (4.2%). Complete resection occurred in 24 patients (100.0%). Postoperatively, one patient (4.2%) suffered stroke. No mortalities occurred within or beyond 30 days of surgery. Persistent cranial nerve injury occurred in two patients (8.3%) with vocal cord paralysis. There was no recurrence of CBT through last follow-up. Five patients (20.8%) were diagnosed with other neoplasms after resection, including basal cell carcinoma, contralateral carotid body tumor, glomus vagale, and glomus jugulare. There was 100% survival at 1 year in patients followed for that time (n = 17). Surgical treatment remains the first-line curative treatment to relieve symptoms and ensure non-recurrence. While acceptable, neurologic complications are significant and therefore detailed preoperative informed consent is mandatory.

Iatrogenic Lumbar Arachnoid Cyst Fenestration for Tethered Cord: 2-Dimensional Operative Video.

Iatrogenic lumbar arachnoid cysts are a rare occurrence after intradural surgery.1,2 To our knowledge, there is only 1 other previous case reported in the literature contributing to a symptomatic tethered cord.3 We present a surgical video (Video 1) demonstrating the history, preoperative workup, and operative technique for exploration and fenestration of a symptomatic iatrogenic lumbar arachnoid cyst with a tethered cord. The patient is a 57-year-old female with a history of a closed neural tube defect with a lipoma that was resected over 20 years before her evaluation. She was lost to follow-up and did not retain any previous medical documentation. She complained of a 2-month history of progressive bilateral lower extremity weakness, leg pain, and worsening of chronic urinary incontinence. Imaging demonstrated a cystic lesion compressing her conus and cauda equina at the L3-4 level. The risks, benefits, and alternatives were discussed, and the patient elected to proceed with surgery. Intraoperative findings demonstrated a complex multiloculated arachnoid cyst with tethering of the conus. The cysts were dissected from the conus and fenestrated, allowing spontaneous flow of cerebrospinal fluid and conus pulsations. Biopsy of the cyst wall confirmed the diagnosis of arachnoid cyst without neoplastic tissue. Due to the presence of multiple loculations, primary pial closure could not be performed. Thus, a circumferential detethering of the conus was performed to ensure complete decompression of the neural elements. Postoperatively, the patient demonstrated improvement in her bilateral lower extremity pain and weakness. Magnetic resonance imaging was scheduled during routine follow-up at 3 months.

Prognostic factors and survival in low grade gliomas of the spinal cord: A population-based analysis from 2006 to 2012.

PURPOSE: Primary spinal cord tumors are rare, and evidence-based management of these patients remains a source of controversy. This study used a large cohort of low-grade spinal cord astrocytomas to determine the effectiveness of prognostic factors and survival. METHODS: The Surveillance, Epidemiology, and End Results (SEER) cancer registry was used to identify patients with WHO grade I-II primary spinal cord astrocytomas from 1973 to 2012; however, patients before 2006 were excluded due to ambiguity diagnosis. Univariate and multivariate Cox proportional hazard models were created to compare survival across covariates and summarized using the Kaplan-Meier method. RESULTS: A total of 561 patients with low-grade glioma (astrocytoma) were identified. Among these, 15.5% of patients received a gross total resection (GTR), 26.1% subtotal resection (STR), and 46.2% unidentified extent of resection. 59.4% did not receive any radiation therapy at any point of the treatment course, while 40.6% underwent radiation therapy. In our cohort, only patients with GTR demonstrated statistically improved survival (HR: 0.22, P < 0.001). Patients with STR had nearly identical survival compared to patients with no surgery (HR: 0.98), and radiotherapy was associated with increased odds of mortality (HR: 1.47, P < 0.001). Multivariate analysis demonstrated a significant survival benefit among patients with younger age, GTR and absence of radiotherapy. Histologic grade did not statistically impact survival. CONCLUSION: Our study suggests that GTR results in improved survival among patients with low-grade gliomas within the spinal cord. Future, considerable data research efforts will aim to better define the role of radiotherapy and tumor grading in this patient population.

Management of vertebral fragility fractures: a clinical care pathway developed by a multispecialty panel using the RAND/UCLA Appropriateness Method.

BACKGROUND CONTEXT: Vertebral fragility fractures (VFFs), mostly due to osteoporosis, are very common and are associated with significant morbidity and mortality. There is a lack of consensus on the appropriate management of patients with or suspected of having a VFF. PURPOSE: This work aimed at developing a comprehensive clinical care pathway (CCP) for VFF. STUDY DESIGN/SETTING: The RAND/UCLA Appropriateness Method was used to develop patient-specific recommendations for the various components of the CCP. The study included two individual rating rounds and two plenary discussion sessions. METHODS: A multispecialty expert panel (orthopedic and neurosurgeons, interventional [neuro]radiologists and pain specialists) assessed the importance of 20 signs and symptoms for the suspicion of VFF, the relevance of 5 diagnostic procedures, the appropriateness of vertebral augmentation versus nonsurgical management for 576 clinical scenarios, and the adequacy of 6 aspects of follow-up care. RESULTS: The panel identified 10 signs and symptoms believed to be relatively specific for VFF. In patients suspected of VFF, advanced imaging was considered highly desirable, with MRI being the preferred diagnostic modality. Vertebral augmentation was considered appropriate in patients with positive findings on advanced imaging and in whom symptoms had worsened and in patients with 2 to 4 unfavorable conditions (eg, progression of height loss and severe impact on functioning), dependent on their relative weight. Time since fracture was considered less relevant for treatment choice. Follow-up should include evaluation of bone mineral density and treatment of osteoporosis. CONCLUSIONS: Using the RAND/UCLA Appropriateness Method, a multispecialty expert panel established a comprehensive CCP for the management of VFF. The CCP may be helpful to support decision-making in daily clinical practice and to improve quality of care.

Challenges of Managing Patients with Symptomatic Large Traumatic Cervical Pseudomeningoceles.

BACKGROUND: Traumatic cervical pseudomeningoceles (TCPs) occur secondary to traction of the cervical nerve roots resulting in violation of the dura. Surgical repair is not necessary in most cases because pseudomeningoceles have a high propensity to spontaneously resolve with conservative management alone. Currently, there are a limited number of cases of large TCPs (large is defined as ≥6 cm in greatest diameter), and there is no established guideline for the management of such lesions. CASE DESCRIPTION: We describe the cases of 2 young men in their 20s who were involved in a motor vehicle accident. Both patients suffered a brachial plexus injury and developed large TCPs. Patient 1 was treated surgically for TCP using a combined intra-/extradural approach using a fascia lata graft. Patient 2 was ultimately treated nonsurgically because a spontaneous resolution of the pseudomeningocele was achieved over the period of 7 months after the accident. Both patients underwent brachial plexus repair surgery consisting of spinal accessory nerve transfer to the suprascapular nerve and intercostal nerve transfer to the musculocutaneous nerve. CONCLUSIONS: Disease progression of TCPs is a dynamic process, and even large lesions may spontaneously resolve without surgical intervention. When surgery is indicated, a definitive dural repair using a fascia lata graft to cover the dural tear intra- and extradurally is an effective method. Surgery must be planned carefully on a case-by-case basis, and close follow-up with thorough physical examination and serial imaging is critical to monitor disease progression.

Spine fusion cross-link causing delayed dural erosion and CSF leak: case report.

The past 2 decades have seen a considerable increase in the number of lumbar spinal fusion surgeries. To enhance spinal stabilization and fusion, make the construct resistant to or stiffer for axial stress loading, lateral bending, and torsional stresses, cross-links and connectors were designed and included in a rod-screw construct. The authors present the case of a 49-year-old woman who presented 11 years after undergoing an L4-5 decompression and fusion in which a pedicle screw-rod construct with an integrated cross-link was designed to attach onto the pedicle screws. The patient's response at the time to the initial surgery was excellent; however, at the time of presentation 11 years later, she had significant postural headaches, severe neurogenic claudication, and radiculopathy. Imaging revealed canal compression across the instrumented levels and a possible thickened adherent filum terminale. Reexploration of the level revealed a large erosive dural defect with a CSF leak, spinal canal compression, and a thickened filum at the level of the cross-link. To the author's knowledge, such complications have not been reported in literature. The authors discuss this rare complication of spinal fusion and the need to avoid dural compression when cross-links are used.

Migration to the ICD-10 coding system: A primer for spine surgeons (Part 1).

BACKGROUND: On 1 October 2015, a new federally mandated system goes into effect requiring the replacement of the International Classification of Disease-version 9-Clinical Modification (ICD-9-CM) with ICD-10-CM. These codes are required to be used for reimbursement and to substantiate medical necessity. ICD-10 is composite with as many as 141,000 codes, an increase of 712% when compared to ICD-9. METHODS: Execution of the ICD-10 system will require significant changes in the clinical administrative and hospital-based practices. Through the transition, diminished productivity and practice revenue can be anticipated, the impacts of which the spine surgeon can minimizeby appropriate education and planning. RESULTS: The advantages of the new system include increased clarity and more accurate definitions reflecting patient condition, information relevant to ambulatory and managed care encounters, expanded injury codes, laterality, specificity, precise data for safety and compliance reporting, data mining for research, and finally, enabling pay-for-performance programs. The disadvantages include the cost per physician, training administrative staff, revenue loss during the learning curve, confusion, the need to upgrade hardware along with software, and overall expense to the healthcare system. CONCLUSIONS: With the deadline rapidly approaching, gaps in implementation result in delayed billing, delayed or diminished reimbursements, and absence of quality and outcomes data. It is thereby essential for spine surgeons to understand their role in transitioning to this new environment. Part I of this article discusses the background, coding changes, and costs as well as reviews the salient features of ICD-10 in spine surgery.

Implementation and impact of ICD-10 (Part II).

BACKGROUND: The transition from the International Classification of Disease-9(th) clinical modification to the new ICD-10 was all set to occur on 1 October 2015. The American Medical Association has previously been successful in delaying the transition by over 10 years and has been able to further postpone its introduction to 2015. The new system will overcome many of the limitations present in the older version, thus paving the way to more accurate capture of clinical information. METHODS: The benefits of the new ICD-10 system include improved quality of care, potential cost savings, reduction of unpaid claims, and improved tracking of healthcare data. The areas where challenges will be evident include planning and implementation, the cost to transition, a shortage of qualified coders, training and education of the healthcare workforce, and a loss of productivity when this occurs. The impacts include substantial costs to the healthcare system, but the projected long-term savings and benefits will be significant. Improved fraud detection, accurate data entry, ability to analyze cost benefits with procedures, and enhanced quality outcome measures are the most significant beneficial factors with this change. RESULTS: The present Current Procedural Terminology and Healthcare Common Procedure Coding System code sets will be used for reporting ambulatory procedures in the same manner as they have been. ICD-10-PCS will replace ICD-9 procedure codes for inpatient hospital services. The ICD-10-CM will replace the clinical code sets. Our article will focus on the challenges to execution of an ICD change and strategies to minimize risk while transitioning to the new system. CONCLUSION: With the implementation deadline gradually approaching, spine surgery practices that include multidisciplinary health specialists have to anticipate and prepare for the ICD change in order to mitigate risk. Education and communication is the key to this process in spine practices.

Intraoperative image-guided spinal navigation: technical pitfalls and their avoidance.

Spinal instrumentation has made significant advances in the last two decades, with transpedicular constructs now widely used in spinal fixation. Pedicle screw constructs are routinely used in thoracolumbar-instrumented fusions, and in recent years, the cervical spine as well. Three-column fixations with pedicle screws provide the most rigid form of posterior stabilization. Surgical landmarks and fluoroscopy have been used routinely for pedicle screw insertion, but a number of studies reveal inaccuracies in placement using these conventional techniques (ranging from 10% to 50%). The ability to combine 3D imaging with intraoperative navigation systems has improved the accuracy and safety of pedicle screw placement, especially in more complex spinal deformities. However, in the authors' experience with image guidance in more than 1500 cases, several potential pitfalls have been identified while using intraoperative spinal navigation that could lead to suboptimal results. This article summarizes the authors' experience with these various pitfalls using spinal navigation, and gives practical tips on their avoidance and management.

Radiographic fusion rate after implantation of facet bone dowels.

BACKGROUND CONTEXT: Achieving a posterolateral fusion in conjunction with performing decompressive laminectomies can prevent recurrence of stenosis or worsening of spondylolisthesis. Facet bone dowels have been introduced and marketed as a less invasive alternative to pedicle screws. Surgeons have been placing them during lumbar laminectomy surgery and coding for intervertebral biomechanical device and posterolateral fusion. These bone dowels have also been placed percutaneously in outpatient surgery centers and pain clinics for facet-mediated back pain. PURPOSE: To describe fusion outcomes in patients who underwent facet bone dowel placement. STUDY DESIGN/SETTING: Retrospective analysis of a single center's experience. PATIENT SAMPLE: Ninety-six patients comprise the entire cohort of patients who underwent facet bone dowel implantation at our institution with adequate postoperative imaging to determine fusion status. OUTCOME MEASURES: Fusion rates as determined on postoperative computed tomography (CT) scans and dynamic lumbar X-rays if CT is not available. METHODS: Threaded facet bone dowels in this study were placed according to the manufacturer's recommended methods. The bone dowels were placed after open exploration of the facet complex or percutaneously through a tubular retractor on the contralateral side from a microdiscectomy or synovial cyst resection. The most recent available postoperative imaging was reviewed to determine fusion status. RESULTS: Of 96 patients in our series, 6 (6.3%) had a fusion seen on CT and 4 did not exhibit any movement on dynamic lumbar X-rays for a total fusion rate of 10.4% (10/96). Eighty-six (89.6%) patients were shown on imaging to not have a solid fusion either by visualizing a patent facet joint on CT or measurable movement between the flexion and the extension lumbar X-rays. CONCLUSIONS: This article is mainly intended to question whether the implantation of facet bone dowels can produce a solid fusion radiographically. In our experience, the placement of facet bone dowels does not equal the time, skill, or attention to detail that is necessary for a posterolateral lumbar arthrodesis, and our follow-up radiographic studies clearly demonstrate an inadequate fusion rate.

Overdrainage shunt complications in idiopathic normal-pressure hydrocephalus and lumbar puncture opening pressure.

OBJECT: Management of idiopathic normal-pressure hydrocephalus (iNPH) is hard because the diagnosis is difficult and shunt surgery has high complication rates. An important complication is overdrainage, which often can be treated with adjustable-shunt valve manipulations but also may result in the need for subdural hematoma evacuation. The authors evaluated shunt surgery overdrainage complications in iNPH and their relationship to lumbar puncture opening pressure (LPOP). METHODS: The authors reviewed the charts of 164 consecutive patients with iNPH who underwent shunt surgery at their institution from 2005 to 2011. They noted age, sex, presenting symptoms, symptom duration, hypertension, body mass index (BMI), imaging findings of atrophy, white matter changes, entrapped sulci, LPOP, valve opening pressure (VOP) setting, number of valve adjustments, serious overdrainage (subdural hematoma requiring surgery), radiological overdrainage (subdural hematomas or hygroma seen on postoperative imaging), clinical overdrainage (sustained or postural headache), other complications, and improvements in gait, urine control, and memory. RESULTS: Eight patients (5%) developed subdural hematomas requiring surgery. All had an LPOP of greater than 160 mm H2O and an LPOP-VOP of greater than 40 mm H2O. Radiological overdrainage was more common in those with an LPOP of greater than 160 mm H2O than in those with an LPOP of less than 160 mm H2O (38% vs. 21%, respectively; p = 0.024). The BMI was also significantly higher in those with an LPOP of greater than 160 mm H2O (median 30.2 vs. 27.0, respectively; p = 0.005). CONCLUSIONS: Serious overdrainage that caused subdural hematomas and also required surgery after shunting was related to LPOP and LPOP-VOP, which in turn were related to BMI. If this can be replicated, individuals with a high LPOP should have their VOP set close to the LPOP, or even higher. In doing this, perhaps overdrainage complications can be reduced.

Correlation of clinical findings and results of percutaneous balloon compression for patients with trigeminal neuralgia.

OBJECTIVE: To investigate pain relief and recurrence after percutaneous balloon compression (PBC) and its association with type of pain, prior surgery, or other clinical factors. METHODS: Fifty-nine patients with medically refractory trigeminal pain were enrolled into this study. Patients were divided into those with typical trigeminal neuralgia (TN), and those with other types of trigeminal pain or "atypical pain." The post-surgical rate of recurrence was estimated by the Kaplan-Meier method. Cox-proportional hazards models were used to investigate associations between patient characteristics and recurrence of pain. RESULTS: Forty-two patients had TN, 17 patients had atypical pain. At last follow-up, 40 patients had excellent, 9 good, 7 fair and 3 poor pain relief. Recurrence was observed in 35 patients, and was associated with pain type (relative risk (RR)=2.38, 95% confidence interval (CI): 1.22-4.63, P=0.011) and pain duration before PBC (RR=1.33, 95% CI: 1.02-1.72, P=0.033). Other clinical factors were not significant. Two patients had transient paresis of the sixth cranial nerve, however, there were no permanent post-surgical complications. CONCLUSIONS: Our study demonstrates the safety and efficacy of PBC with 83% of patients being pain free at last follow-up. Patients with atypical pain and longer pre-surgical symptom duration appear to have a higher risk of recurrence. Repeat surgery is just as effective as initial surgery, justification for being conservative in parameter selection at the initial procedure to minimize complications.

Early complications of posterior rod-screw fixation of the cervical and upper thoracic spine.

OBJECTIVE: The technique of rod-screw fixation of the cervical spine is well described. However, there is very little data on the complications incurred by the application of these devices. The purpose of this study was to quantify the risks associated with rod fixation of the cervical spine. METHODS: A prospective study was performed on 100 consecutive patients treated with this technique. Clinical and radiographic assessment was performed immediately after surgery 3, 6, and 12 months postoperatively, and annually thereafter. The mean follow-up interval was 16.7 months. RESULTS: A total of 888 screws were implanted in 100 patients. Perioperative complications included radiculopathy (n = 4, 0.45% per screw placed), infection and other wound-healing problems (n = 4), screw malposition (n = 2), loss of alignment (n = 1), and cerebrospinal fluid leak (n = 1). There were no examples of spinal cord or vertebral artery injury. Early complications (within 6 mo of surgery) included pseudarthrosis (n = 2) and screw breakage (n = 2, 0.22% per screw placed). There were no late complications. Reoperation was required in eight cases, all within 6 months of the index procedure. Indications for reoperation included wound-healing problems (n = 4), malpositioned screw (n = 2), and pseudarthrosis (n = 2). No patient required another operation for any indication beyond the 6-month postoperative interval. CONCLUSION: Rod-screw fixation was an effective method of posterior cervical stabilization that could be safely applied in a wide range of spinal disorders. In a complex group of patients, the complication rates were modest, and compared favorably with other methods of fixation.