Noel I. Perin

Review: complications of minimally invasive spinal surgery.

COMPLICATIONS OF MINIMALLY invasive spinal surgery can be related to anesthesia, patient positioning, and surgical technique. The performance of successful minimally invasive spinal surgery is beset with several technical challenges, including the limited tactile feedback, two-dimensional video image quality of three-dimensional anatomy, and the manual dexterity needed to manipulate instruments through small working channels, which all account for a very steep learning curve. Knowledge of possible complications associated with particular minimally invasive spinal procedures can aid in their avoidance. This article reviews complications associated with minimally invasive spinal surgery in the cervical, thoracic, and lumbar spine by reviewing reported data of sufficient detail or with sufficient numbers of patients. In addition, possible complications associated with anesthesia use, patient positioning, and surgical techniques during thoracoscopic and laparoscopic spinal procedures are reviewed.

Endoscopic resection of thoracic paravertebral and dumbbell tumors.

OBJECTIVENeurogenic paravertebral tumors are uncommon neoplasms arising from neurogenic elements within the thorax. These tumors may be dumbbell shaped, extending into the spinal canal or exclusively paraspinal. Generally encapsulated, they are located in the posterior mediastinum. In this report, we present our experience in the thoracoscopic resection of these tumors, including surgical technique and potential pitfalls. METHODSA retrospective review of patients undergoing endoscopic surgery for paravertebral tumors was undertaken. Patient demographics, charts, operative reports, and pre- and postoperative images were reviewed. RESULTSBetween 1997 and 2004, 13 patients were treated thoracoscopically for paravertebral tumors in our departments. Our population consisted of four men and nine women. The median age was 44.9 years (range, 29–66 yr). Eight patients presented with pain, dyspnea, cough, and weakness. Five patients had tumors found incidentally. Sizes of the tumors varied from 3 to 9 cm. Final pathology included four neurofibromas, eight schwannomas, and one unclassified granular cell tumor. Gross total resection was achieved endoscopically in all cases. Three patients required a hemilaminectomy for resection of the intraspinal dumbbell component of the tumor during the same operation. The mean operative time was 229.5 minutes. The mean estimated blood loss was 371.1 ml. Postoperative morbidities included one each of tongue swelling, ulnar neuropathy, and intercostal hyperesthesia. The mean hospital stay was 2.8 days. CONCLUSIONParavertebral tumors in the posterior mediastinum are amenable to endoscopic removal, even in hard to reach locations. Tumors with intraspinal extension can be removed concurrently by performing a hemilaminectomy, followed by thoracoscopy, without the need for a thoracotomy.

Fixation of the axis.

OBJECTIVETo review and compare the techniques of fixation of the axis vertebral segment. Also, to review the anatomy of the axis vertebrae, ligamentous attachments, and unique biomechanics of this segment. METHODSThe use of wire, cable, screw, and plate fixation techniques are reviewed and discussed in the treatment of fractures of C1 and C2 along with utilization of the halo vest and cervical collar during the postoperative period. RESULTSAll fixation methods were useful. However, the appropriate fixation technique is best determined by the local anatomy (eg, anomalous vertebral artery), posterior element fractures, or the necessity to remove the posterior elements for treatment of the underlying condition. CONCLUSIONNew techniques for fixation and instrumentation for fixation of the axis are available. Advanced imaging allows for advanced aggressive instrumentation while avoiding injury to adjacent structures. Biomechanical studies have influenced the utility and popularity of each technique.

Revision of Chiari decompression for patients with recurrent syrinx

The management of adult patients with Chiari malformation associated with syrinx remains controversial. Although an abundance of literature exists for the pediatric population, there is an absence of guidelines for the adult population. It is unclear which of the different surgical approaches is appropriate in patients with Chiari I malformations and syringomyelia. A 36-year-old female patient had a posterior fossa decompression 3years prior to recurrence. The patient developed recurrent symptoms with sensory loss and hyperesthesia in the right upper extremity. MRI revealed decreased cerebrospinal fluid flow at the craniocervical junction. The patient was taken to the operating room for revision of the posterior fossa decompression, lysis of adhesions and duraplasty. Re-exploration of a Chiari decompression, lysis of adhesions and revision duraplasty is an effective treatment option for recurrent syringomyelia.

Lateral access to paravertebral tumors

Traditional transabdominal and retroperitoneal approaches for paravertebral tumors can be associated with injury to the viscera and lumbar plexus. The authors provide a technical description of a known approach with a new application for the resection of paraspinal tumors using both open and minimally invasive transpsoas techniques and report on 2 illustrative cases. In both cases, gross-total resection of the tumor was achieved and the patients experienced resolution of their presenting neurological symptoms, although one of the patients required 2 extra days of hospitalization due to an asymptomatic retroperitoneal hematoma, which was conservatively managed. The authors conclude that the lateral transpsoas approach is a safe approach for paravertebral tumors and may not require an access surgeon.

Arthritic and Bone-Softening Diseases of the Craniocervical Junction

Rheumatoid arthritis and other bone-softening diseases such as Pagets disease, osteogenesis imperfecta, rickets, osteomalacia, and hyperparathyroidism have the potential to destabilize the upper cervical spine. In these disease settings, the relation between the occiput, axis, and atlas may be altered and destabilized. This paper reviews the anatomy, clinical presentation, and pathogenesis of the different diseases, as well as their medical and surgical management at the occipitocervical junction.