Biomedical subjects
Publications and source records attributed to Sean D Christie.
This article provides an overview of a minimally invasive approach for lumbar discectomy and foraminotomy. The surgical technique is described in detail, and the current literature is reviewed to assess the clinical efficacy of the procedure.
Percutaneous vertebroplasty and kyphoplasty provide minimally invasive options for the management of osteoporotic and osteolytic vertebral compression fractures. These techniques provide substantial pain relief and support without requiring long periods of recumbency, and have an acceptable complication rate. Vertebral augmentation techniques such as vertebroplasty and kyphoplasty provide pain relief and improvement in quality of life in the highly selected patient. Complications can be avoided with careful surgical technique, and good outcomes can be achieved with proper patient selection.
Cervical stenosis and cervical spondylotic myelopathy are common disorders seen by many spine surgeons. Presentation can range from asymptomatic to myelopathy or myeloradiculopathy to lower extremity and gait problems attributed to lumbar disease. Various surgical procedures are practiced in the surgical management of this disease. Posterior cervical laminectomy is a familiar procedure and is the treatment of choice for multilevel disease. With the development of newer instruments and access devices, it has become possible to treat this problem through a minimally invasive approach.
OBJECTIVE: Spinal intradural-extramedullary neoplasms are uncommon lesions that usually cause pain or neurological deficit secondary to neural compression. Traditional treatment of these tumors includes open laminectomy with intradural resection. We describe an alternative minimally invasive surgical technique in a consecutive series of patients undergoing treatment for symptomatic lesions. METHODS: Six patients (four men, two women) presented with symptoms including pain (five out of six) and/or neurological deficit (two out of six) with radiographic evidence of intradural pathology. All patients underwent surgical resection using a minimally invasive, unilateral approach. Pain relief was analyzed using the visual analog scale and magnetic resonance imaging to evaluate the extent of resection. Traditional laminectomy for tumor resection disrupts the muscular, ligamentous, and bony structures of the spine, which may contribute to pain and instability. Minimally invasive resection of intradural tumors offers the option of reducing approach morbidity when resecting these lesions. Using a tubular retractor system (X-Tube, Medtronic Sofamor-Danek, Memphis, TN) and microscopic surgical techniques, we were able to resect different intradural lesions successfully. RESULTS: All patients underwent successful, complete resection of their intradural-extramedullary tumors. The average patient age was 47 years (range, 41-60 yr) with one cervical, one thoracic, and four lumbar lesions. The mean operative time was 247 minutes (range, 180-320 min), the estimated blood loss was 56 mLs (range, 40-75 mLs), and the hospital stay was 57 hours (range, 48-80 h). Histologically, five tumors were determined to be schwannomas and one was identified as a myxopapillary ependymoma. There were no complications associated with this surgical technique. Postoperative magnetic resonance imaging demonstrated complete resection in all cases. CONCLUSION: Intradural-extramedullary neoplasms can be safely and effectively treated with minimally invasive techniques. Potential reduction in blood loss, hospitalization and disruption to local tissues suggest that, in the hands of an experienced surgeon, this technique may present an alternative to traditional open tumor resection.
STUDY DESIGN: A literature review. OBJECTIVES: To evaluate the mechanisms of action and effectiveness of interspinous distraction devices in managing symptomatic lumbar spinal pathology. SUMMARY OF BACKGROUND DATA: Fusion operations have traditionally been used to manage many disorders of the lumbar spine related to deformity, pain, or instability. Concern over the long-term effects of fusion on adjacent segments has led to the development of the concept of dynamic stabilization. METHODS: A Medline search was performed using the key words "interspinous implants," "interspinous devices," and "lumbar dynamic stabilization." The abstracts of each were reviewed. Relevant articles were reviewed in detail and other appropriate references obtained. In addition, when available, nonpublished manufacturer's information was reviewed. RESULTS: Articles describing the following implants were included in this review: the Minns Device, the Interspinous "U," the Diam, the Wallis Implant, and the X STOP. CONCLUSIONS: These devices continue to be evaluated in clinical trials. Early results suggest a possible role in the management of degenerative disorders of the lumbar spine.
Management of upper thoracic spinal fractures continues to be a challenging task for spinal surgeons. Appropriate treatment depends on a variety of factors, including the nature of the fracture, the need for neural decompression, and the need for spinal stabilization. A number of surgical approaches have been developed to address these lesions. Each approach carries its own inherent advantages and disadvantages and an understanding of each is required to optimize the treatment of any individual patient. As our surgical experience and expertise continues to grow in the field of minimally invasive surgery, these techniques and novel approaches will provide alternatives for our patients that will maintain the current quality of care but minimize surgical trauma and improve recovery times.
OBJECTIVES: Central neurocytoma is a tumour that typically occurs in young adults in close association with the lateral and third ventricles of the cerebrum. METHODS: We report the unusual case of a central neurocytoma that developed in the fourth ventricle of a 59-year-old woman and metastasized to the upper cervical canal. Subtotal excision and adjuvant radiotherapy were used to treat the lesion. Microscopic evaluation, discussion of the pathologic differential diagnosis and theories of the histogenesis of the tumour are presented. RESULTS AND CONCLUSIONS: Fourth ventricular neurocytoma is rare and has only been reported twice previously. It appears most likely that this tumour arises from subependymal progenitor cell lines.