Emily Sieg

Systematic Review and Meta-analysis of Chiropractic Care and Cervical Artery Dissection: No Evidence for Causation.

Background Case reports and case control studies have suggested an association between chiropractic neck manipulation and cervical artery dissection (CAD), but a causal relationship has not been established. We evaluated the evidence related to this topic by performing a systematic review and meta-analysis of published data on chiropractic manipulation and CAD. Methods Search terms were entered into standard search engines in a systematic fashion. The articles were reviewed by study authors, graded independently for class of evidence, and combined in a meta-analysis. The total body of evidence was evaluated according to GRADE criteria. Results Our search yielded 253 articles. We identified two class II and four class III studies. There were no discrepancies among article ratings (i.e., kappa=1). The meta-analysis revealed a small association between chiropractic care and dissection (OR 1.74, 95% CI 1.26-2.41). The quality of the body of evidence according to GRADE criteria was “very low.” Conclusions The quality of the published literature on the relationship between chiropractic manipulation and CAD is very low. Our analysis shows a small association between chiropractic neck manipulation and cervical artery dissection. This relationship may be explained by the high risk of bias and confounding in the available studies, and in particular by the known association of neck pain with CAD and with chiropractic manipulation. There is no convincing evidence to support a causal link between chiropractic manipulation and CAD. Belief in a causal link may have significant negative consequences such as numerous episodes of litigation.

Case Report: A Rosette-forming Glioneuronal Tumor in the Tectal Plate in a Patient with Neurofibromatosis Type I

We report the case of a 41–year-old female with neurofibromatosis Type 1 (NF1) who developed a rosette-forming glioneuronal tumor (RGNT) in the tectal plate. This tumor was diagnosed in 2002 when the patient presented with obstructive hydrocephalus, which was subsequently treated with a ventriculoperitoneal shunt and then an endoscopic third ventriculostomy. Initially thought to be a pilocytic astrocytoma, it was followed with serial magnetic resonance imaging (MRI) until tumor progression and development of a large fourth ventricular cystic component prompted resection via suboccipital craniotomy. Histological examination demonstrated an RGNT, a WHO Grade 1 tumor, with neurocytic rosettes, perivascular pseudorosettes, and elements resembling a pilocytic astrocytoma. Initially, the patient did well after her craniotomy, but postoperative complications set in that eventually led to her death. In this case report, we describe a relatively rare tumor that, despite its benign nature, leads to frequent complications and deficits due to its surgically challenging location. Along with previously reported examples, this cases raises the possibility of a causal relationship between NF1 and RGNT.

The angular course of the median nerve in the distal forearm and its anatomical importance in preventing nerve injury in a modern era of carpal tunnel release

OBJECTIVE A thorough understanding of anatomy is critical for successful carpal tunnel release. Several texts depict the median nerve (MN) as taking a course parallel to the long axis of the forearm (LAF). The authors report on their attempt to formally assess the course of the MN as it travels to the carpal tunnel in the distal wrist and discuss its potential clinical significance. METHODS The width of the wrist, the distance from the radial wrist to the MN, and the distance from the distal volar wrist crease to the point where the MN emerges between the flexor carpi radialis (FCR) tendon and the flexor digitorum superficialis (FDS) tendons were recorded during cadaveric dissection of 76 wrist specimens. The presence or absence of palmaris longus was documented. Finally, the angles between the MN and FCR tendon and between the MN and the LAF were measured using ImageJ. RESULTS The relative position of the MN at the distal wrist crease, as determined by the ratio of the distance from the MN to the radial wrist divided by wrist width, revealed a mean value of 0.48, indicating that the nerve was usually located just radial to midline. The mean distance between the distal wrist crease and the MNs emergence was 34.6 mm. The mean angle between the MN and the FCR tendon was 14.1°. The angle between the MN and the LAF had a mean value of 8.8° (range 0.0°-32.2°). The nerve was parallel to the LAF in only 10.7% of the studied wrists. Palmaris longus was absent in 14 (18.4%) of the 76 wrists. CONCLUSIONS The MN takes an angular approach to the carpal tunnel in the distal wrist in the vast majority of cases. This newly described finding will be useful to both clinicians and anatomists.

Fracture related ulnar and sciatic nerve transections: a report of two cases and literature review

IntroductionCase reports, case series, and case control studies have looked at the incidence of complete nerve transection in the setting of fracture and the need for surgical exploration dating back to the 1920s. We present two cases of nerve laceration accompanying traumatic fracture with a thorough review of the literature.MethodsWe used the following search terms: “ulnar nerve” OR “sciatic nerve” AND “laceration” OR “transection” AND “fracture.” Results were reviewed and included for discussion if they specifically reported ulnar or sciatic nerve laceration accompanying traumatic fracture.ResultsOur search yielded 15 papers reporting a total of 10 ulnar nerve lacerations and nine sciatic nerve lacerations. We present two additional cases. The first is a patient with a humerus fracture and complete ulnar nerve transection. The second case is a patient who suffered a femur fracture and complete transection of the sciatic nerve.ConclusionNerve laceration accompanying traumatic fracture is rare. We review the reported cases of nerve laceration and present two cases treated at our institution. Though uncommon, nerve laceration should be considered in the setting of traumatic fracture with neurological injury, particularly open fractures.

Evaluating the evidence: is neurolysis or neurectomy a better treatment for meralgia paresthetica?

BackgroundMeralgia paresthetica is a mononeuropathy of the lateral femoral cutaneous nerve (LCFN). Surgical treatment involves transection or decompression of the LCFN. There is no clear consensus on the superiority of one technique over the other. We performed a systematic review of the literature to answer this question.MethodsEligible studies included those that compared neurolysis versus neurectomy for the treatment of meralgia paresthetica after failure of conservative therapy. Our outcome of interest was resolution of symptoms. We performed a computerized search of MEDLINE (PubMed; all years) and of the Cochrane Central Register of Controlled Trials. Eligible studies had to include the words “meralgia paresthetica” and “surgery.” All patients regardless of age were included, and there was no language restriction. We then reviewed the articles’ titles and abstracts. All studies that compared neurolysis to neurectomy were included in the analysis.ResultsOf the studies identified, none were randomized controlled trials. There were two German language articles that were translated by a third researcher.Each study was evaluated by two independent researchers who assigned a level of evidence according to American Association of Neurologist algorithm and also performed data extraction (neurolysis vs. neurectomy and resolution of pain symptoms). Each study was found to be level four evidence.ConclusionAfter reviewing the data, there was insufficient evidence to recommended one method of treatment over the other. This highlights the importance of keeping a national registry in order to compare outcomes between the two methods of treatment.

Intraventricular Undifferentiated Pleomorphic Sarcoma: A Case Report

Undifferentiated pleomorphic sarcoma is a histologic diagnosis based on cell morphology. These tumors are found throughout the body. They are rarely found in the central nervous system and almost never occur as a primary intraventricular tumor. We present the unusual case of a 68-year-old woman with an intraventricular undifferentiated pleomorphic sarcoma. We go on to discuss the clinical presentation, radiographic characteristics, and management paradigm for these rare lesions. Our patient presented with acute confusion, inability to balance a checkbook, and gait imbalance. CT and MRI demonstrated a 4 x 3.6 x 3.6 cm enhancing lesion in the left lateral ventricle abutting the foramen of Monro. Pathology revealed an undifferentiated pleomorphic sarcoma.

Management of nerve compression in multiple hereditary exostoses: a report of two cases and review of the literature.

PurposeMultiple hereditary exostoses (MHE) is a rare autosomal dominant condition that results in the growth of cartilage-capped prominences that often cause nerve compression and injury. Many patients suffer from continued and debilitating chronic pain which leads some to advocate avoiding surgical intervention in patients with multiple hereditary exostoses. We present a review of the literature as well as a case series at our institution in order to evaluate the role of surgery in multiple hereditary exostoses.MethodsWe searched the literature for reports of patients with multiple hereditary exostoses undergoing surgery for nerve compression. We then reviewed the recent experience at our institution which revealed two patients with multiple hereditary exostoses.ResultsOur literature search revealed that there have been several case series and retrospective analyses in the literature that assess the benefit of surgery in the case of nerve compression caused by exostoses. The majority of these reports are of solitary exostoses. Few reports expand on the role of surgery in patients with multiple hereditary exostoses suffering from nerve compressions secondary to bony overgrowth. A recent review of the experience at our institution revealed two patients with multiple hereditary exostoses who together underwent a total of four surgeries for treatment of peripheral nerve compression resulting in pain or weakness. Postoperative evaluation revealed improvement in pain and/or motor strength following each operation.ConclusionBased on our experience and literature review, we advocate that nerve compression in selected individuals with multiple hereditary exostoses that results in neurological injury should be considered for nerve decompression and resection of the offending exostosis.

Comorbidities and Positioning: Morbid Obesity and Multiple Trauma

Neurosurgical positioning is challenging even in a controlled environment. Comorbidities such as morbid obesity and polytrauma make operative positioning even more challenging. Prone positioning requires extra thought and preparation, especially in the obese patient. Extensive preoperative workup may be required. Intra-abdominal pressure should be minimized. Great care must be taken when positioning to avoid peripheral nerve injury, pressure points sores, and ischemic optic neuropathy. Positioning of the polytrauma patient is equally challenging and requires cooperation between the anesthesia team and multiple surgical teams in time-pressured emergency situations. Protection of the spine during intubation and positioning is key.

Use of Multimodality Neuromonitoring in the Management of Traumatic Brain Injury

Multimodality neuromonitoring has become an essential part of neurocritical care over the past several decades. Ideally, the management strategies employed based on the information provided by multimodality monitoring should minimize secondary injury and not instigate deleterious effects. The aim of this chapter is to discuss available advanced neuromonitoring techniques, to review evidence for patient outcomes in the setting of multimodality monitoring, and to discuss in brief the logistical implications of implementing these techniques in the neurocritical care unit.

Management of Traumatic Brain Injury

Traumatic brain injury remains a serious public health problem, causing death and disability for millions. In order to maximize outcomes in the face of a complex injury to a complex organ, a variety of advanced neuromonitoring techniques may be used to guide surgical and medical decision-making. Because of the heterogeneity of injury types and the plethora of treatment confounders present in this patient population, the scientific study of specific interventions is challenging. This challenge highlights the need for a firm understanding of the anatomy and pathophysiology of brain injuries when making clinical decisions in the intensive care unit.