Alexander Tuchman

The indications and timing for operative management of spinal epidural abscess: literature review and treatment algorithm

OBJECT Delayed or inappropriate treatment of spinal epidural abscess (SEA) can lead to serious morbidity or death. It is a rare event with significant variation in its causes, anatomical locations, and rate of progression. Traditionally the treatment of choice has involved emergency surgical evacuation and a prolonged course of antibiotics tailored to the offending pathogen. Recent publications have advocated antibiotic treatment without surgical decompression in select patient populations. Clearly defining those patients who can be safely treated in this manner remains in evolution. The authors review the current literature concerning the treatment and outcome of SEA to make recommendations concerning what population can be safely triaged to nonoperative management and the optimal timing of surgery. METHODS A PubMed database search was performed using a combination of search terms and Medical Subject Headings, to identify clinical studies reporting on the treatment and outcome of SEA. RESULTS The literature review revealed 28 original case series containing at least 30 patients and reporting on treatment and outcome. All cohorts were deemed Class III evidence, and in all but two the data were obtained retrospectively. Based on the conclusions of these studies along with selected smaller studies and review articles, the authors present an evidence-based algorithm for selecting patients who may be safe candidates for nonoperative management. CONCLUSIONS Patients who are unable to undergo an operation, have a complete spinal cord injury more than 48 hours with low clinical or radiographic concern for an ascending lesion, or who are neurologically stable and lack risk factors for failure of medical management may be initially treated with antibiotics alone and close clinical monitoring. If initial medical management is to be undertaken the patient should be made aware that delayed neurological deterioration may not fully resolve even after prompt surgical treatment. Patients deemed good surgical candidates should receive their operation as soon as possible because the rate of clinical deterioration with SEA is notoriously unpredictable. Although patients tend to recover from neurological deficits after treatment of SEA, the time point when a neurological injury becomes irreversible is unknown, supporting emergency surgery in those patients with acute findings.

Influence of T1 Slope on the Cervical Sagittal Balance in Degenerative Cervical Spine: An Analysis Using Kinematic MRI.

Study Design. A retrospective kinematic magnetic resonance imaging (kMRI) study. Objective. To evaluate the utility of kMRI in determining the relationship between cervical sagittal balance and TI alignment. Summary of Background Data. Thoracic inlet parameters play an important role in cervical spine sagittal balance. However, most of the literature is based on lower resolution cervical X-rays or CT scans in the supine position. Methods. Cervical spine kMRI of 83 patients with degenerative cervical spine conditions (20–68 yr of age) was analyzed for: (1) cervical spine parameters: C2–C7 angle, C2–C7 sagittal vertical axis (SVA), cranial tilt, and cervical tilt; and (2) T1 parameters: thoracic inlet angle (TIA), T1 slope, and neck tilt (NT). Multiple logistic regression analysis and Pearson correlation coefficients were performed. Results. The mean TIA, T1 slope, and NT were 78.0, 33.2, and 44.8°, respectively. The mean C2–7 angle, SVA of C2–C7, cervical tilt, and cranial tilt were −15.4°, 22.0 mm, 18.1°, and 15.1°, respectively. The ratio of cervical:cranial tilt was maintained as 55:45%. A significant correlation was found between the C2–C7 angle and T1 slope (r = 0.731), TIA and C2–C7 angle (r = 0.406), cervical tilt with C2–C7 angle (r = 0.671), T1 slope with TIA (r = 0.429), TIA with neck tilt (r = 0.733), TIA with cervical tilt (r = 0.377), SVA C2–C7 with cervical tilt (r = −0.480), SVA C2–C7 with cranial tilt (r = 0.912), and C2–7 SVA with the ratio of cranial tilt to cervical tilt (r = 0.694). Conclusion. An individual with a large T1 slope required large cervical lordosis to preserve physiologic sagittal balance of the cervical spine. Cranial tilt was the cervical parameter most strongly correlated with SVA C2–C7, and thus may be a good parameter to assess decompensation of cervical sagittal balance. Level of Evidence: 3

Surgery and Radiosurgery for Acromegaly: A Review of Indications, Operative Techniques, Outcomes, and Complications

Among multimodality treatments for acromegaly, the goals of surgical intervention are to balance maximal tumor resection while preserving normal pituitary function and maintaining patient safety. The resection of growth hormone-(GH-) secreting pituitary adenomas in the hands of experienced surgeons results in hormonal remission in 50–70% of patients. Acromegalic patients often have medical comorbidities and anatomical variations complicating anesthesia and surgical management. Despite these challenges, complications such as CSF leak or new hypopituitarism following surgery remain uncommon. Over the past decade, endoscopic approaches to pituitary tumors have improved visualization and facilitated identification of additional tumor using angled telescopes. Patients with persistent acromegaly following surgery require continued medical and/or radiation-based interventions. The adjunctive use of stereotactic radiosurgery offers hormonal remission in 40–50% of patients. In this article, the current preoperative evaluation, indications for surgery, surgical approaches, role of radiosurgery, complications, and remission criteria following operative resection of GH adenomas are reviewed.

Iliac Crest Bone Graft versus Local Autograft or Allograft for Lumbar Spinal Fusion: A Systematic Review

Study Design Systematic review. Objective To compare the effectiveness and safety between iliac crest bone graft (ICBG) and local autologous bone and allograft in the lumbar spine. Methods A systematic search of multiple major medical reference databases identified studies evaluating spinal fusion in patients with degenerative joint disease using ICBG, local autograft, or allograft in the thoracolumbar spine. Results Six comparative studies met our inclusion criteria. A “low” strength of the overall body of evidence suggested no difference in fusion percentages in the lumbar spine between local autograft and ICBG. We found no difference in fusion percentages based on low evidence comparing allograft with ICBG autograft. There were no differences in pain or functional results comparing local autograft or allograft with ICBG autograft. Donor site pain and hematoma/seroma occurred more frequently in ICBG autograft group for lumbar fusion procedures. There was low evidence around the estimate of patients with donor site pain following ICBG harvesting, ranging from 16.7 to 20%. With respect to revision, low evidence demonstrated no difference between allograft and ICBG autograft. There was no evidence comparing patients receiving allograft with local autograft for fusion, pain, functional, and safety outcomes. Conclusion In the lumbar spine, ICBG, local autograft, and allograft have similar effectiveness in terms of fusion rates, pain scores, and functional outcomes. However, ICBG is associated with an increased risk for donor site-related complications. Significant limitations exist in the available literature when comparing ICBG, local autograft, and allograft for lumbar fusion, and thus ICBG versus other fusion methods necessitates further investigation.

Evaluation of Effect of Weekend Admission on the Prevalence of Hospital-Acquired Conditions in Patients Receiving Cervical Fusions

BACKGROUND Hospital-acquired conditions (HACs) are defined by the Centers for Medicaid and Medicare Services (CMS) as preventable adverse events that do not qualify for reimbursement of resulting hospital costs. HACs have been employed as a metric for quality of patient care. Patients undergoing cervical spine fusions are at risk for occurrence of HACs because of limited mobility and potential extended hospital length of stay (LOS). Previous studies have not evaluated the contribution of weekend admission on the rate of HACs in this patient population. We abstracted data from the Nationwide Inpatient Sample to evaluate rate of HACs as a function of weekend admission among patients admitted for cervical fusions. METHODS Patients undergoing anterior and posterior cervical fusions were identified from the 2002-2010 Nationwide Inpatient Sample database. HACs as defined by the CMS were collected via International Classification of Diseases, Ninth Revision, Clinical Modification codes. Multivariate analysis, including adjustment for demographics, disease severity, admission acuity, and admission source, was used to evaluate the effect of weekend admission on HAC occurrence, prolonged LOS, and higher inpatient costs. RESULTS During the period 2002-2010, 1,404,181 admissions for cervical fusion were identified. HACs occurred at a frequency of 4.6%. After multivariate adjustment for demographics, disease severity, and urgency of admission, weekend admissions were associated with a 56% increased risk of HAC occurrence compared with weekday admissions (relative risk = 1.56, 95% confidence interval = 1.51, 1.62, P < 0.01). HAC occurrence was independently associated with prolonged LOS and higher inpatient costs (P < 0.05). CONCLUSIONS Patients undergoing cervical fusions who are admitted on weekends have an increased rate of HACs. HACs were associated with increases in LOS and hospital costs. Further study is warranted to evaluate disparities and potential improvement among weekend admissions.

Endoscopic-Assisted Resection of Intracranial Epidermoid Tumors

OBJECTIVE Intracranial epidermoid tumors are epithelially derived lesions that may present particular challenges to neurosurgeons, often encasing critical neurovascular structures and extending into multiple subarachnoid cisterns. We aimed to evaluate our recent experience with endoscopic assistance to craniotomy with microsurgical resection of these lesions. METHODS A retrospective review of patients undergoing endoscopic-assisted craniotomy for resection of an epidermoid tumor at the Keck School of Medicine of University of Southern California between 2009 and 2012 was conducted. In all patients, the surgical approach and tumor resection were first performed microscopically. This was followed by use of an angled endoscope to facilitate further inspection and additional resection of tumor using a two-surgeon technique. RESULTS Twelve patients undergoing 13 consecutive endoscopic-assisted craniotomies were included in the analysis. The mean patient age was 45 years. The mean maximal tumor diameter was 4.0 cm (range, 2.4-5.8 cm). Surgery was for recurrent epidermoid in 6 of 13 cases (46%). Epidermoid tumor location included the cerebellopontine angle (9 patients, 75%), fourth ventricle (2 patients, 17%), and third ventricle (1 patient, 8%). Surgical approaches included retrosigmoid craniotomy (8 patients), suboccipital craniotomy (1 patient), suboccipital craniotomy with supracerebellar approach (1 patient), extradural temporopolar approach (1 patient), and subtemporal approach (1 patient). In 11 of 13 cases (85%), additional tumor was identified upon inspection with an angled endoscope, facilitating additional tumor resection in each case. Gross or deliberate near total resection was achieved in 7 of 13 cases (54%). Four patients (31%) had improvement of cranial nerve function. Postoperative neurological deficits included transient abducens and oculomotor nerve paresis in one patient each. CONCLUSIONS The endoscope is a safe and effective adjunct to the microscope in facilitating additional inspection and further resection of epidermoid tumors. Endoscopic-assisted surgery is particularly useful for identifying and removing additional tumor located around surgical corners.

Reoperation Rates Following Single-Level Lumbar Discectomy.

Study Design. Retrospective analysis of national insurance billing database. Objective. To examine trends in reoperation after single-level lumbar discectomy. Summary of Background Data. Lumbar discectomy is the most commonly performed procedure for treatment of radiculopathy caused by disc herniation. Randomized clinical trials have demonstrated the advantage of discectomy over nonsurgical treatment options, allowing for a more rapid reduction in symptoms. However, population-level data regarding reoperation after single level discectomy is limited. Methods. Data were collected using the commercially available PearlDiver software for patients billed with the Current Procedural Terminology code for our index procedure, hemilaminotomy and removal of disc material, between January 2007 and September 2014. The index group was then followed for up to 4 years for recurrent lumbar surgery, including spinal fusion, laminectomy, and additional discectomy. Results. Analysis of data obtained from 13,654 patient records revealed a rate of additional lumbar surgeries after single-level discectomy of 3.95% (539/13654) within 3 months and 12.2% (766/6274) within 4 years of the index procedure. Lumbar spinal fusion was performed on 5.9% (370/6274) of patients within 4 years. Patients who received a re-exploration discectomy within 2 years of the index procedure went on to receive lumbar fusion at a rate of 38.4% (48/125) within the 4 years after the re-exploration discectomy. The average additional cost of lumbar reoperation, as measured by insurance reimbursement, was approximately

Material Science in Cervical Total Disc Replacement

11,161 per-patient per year. Conclusion. We report an overall 4-year reoperation rate of 12.2% after single-level discectomy. In addition, we report a rate of progression to lumbar fusion following re-exploration discectomy of 38.4% within 4 years of reoperation. Further studies are needed regarding the best treatment algorithm in patients with reherniation or iatrogenic instability after lumbar discectomy. This study should enhance the shared decision making process by providing surgeons and patients with valuable data regarding the frequency and nature of reoperations after discectomy. Level of Evidence: 3

Large solitary osteochondroma of the thoracic spine: Case report and review of the literature

Current cervical total disc replacement (TDR) designs incorporate a variety of different biomaterials including polyethylene, stainless steel, titanium (Ti), and cobalt-chrome (CoCr). These materials are most important in their utilization as bearing surfaces which allow for articular motion at the disc space. Long-term biological effects of implanted materials include wear debris, host inflammatory immune reactions, and osteolysis resulting in implant failure. We review here the most common materials used in cervical TDR prosthetic devices, examine their bearing surfaces, describe the construction of the seven current cervical TDR devices that are approved for use in the United States, and discuss known adverse biological effects associated with long-term implantation of these materials. It is important to appreciate and understand the variety of biomaterials available in the design and construction of these prosthetics and the considerations which guide their implementation.

Radiosurgery for Metastatic Disease at the Craniocervical Junction

Background: Spinal osteochondromas are typically benign tumors, but patients may present with myelopathy and neurologic deficits if there is tumor encroachment within the spinal canal. Case Description: We report here a case of a large solitary osteochondroma originating from the posterior vertebral body of T9 causing spinal cord compression and myelopathy. A 17-year-old man presented with 3 months of bilateral feet numbness and gait difficulty. Imaging demonstrated a large left-sided 5.9 cm × 5.0 cm × 5.4 cm osseous mass arising from the T9 vertebra consistent with an osteochondroma. He underwent bilateral costotransversectomies, and a left two-level lateral extracavitary approach for three partial corpectomies to both safely decompress the spinal canal as well as obtain a gross total resection of the tumor. Use of the O-arm intraoperative stereotactic computed tomographic navigation system assisted in delineating the osseous portions of the tumor for surgical removal. He experienced complete neurologic recovery after operative intervention. Conclusion: Careful surgical planning is needed to determine the best approach for spinal cord decompression and resection of this tumor, especially taking into account the bony elements from which it arises. We present this case, to highlight the feasibility of a single-stage posterior approach to the ventral thoracic spine for the resection of a large solitary thoracic osteochondroma causing cord compression.