. However, these methods, as well as other methods in pediatric craniovertebral fusion, do have a relatively high documented fusion failure rate, 4, 5, 20–22 and complications associated with the halo orthotic device are not infrequent. Although rigid screw stabilization of the atlantoaxial joint has achieved a high degree of success in adult patients, 2, 6, 8, 9 efforts to adapt these techniques to the pediatric population have been described in few reports. 3 We report our experience in managing 10 pediatric patients whose craniovertebral instability was managed by
Douglas L. Brockmeyer and Ronald I. Apfelbaum
Douglas L. Brockmeyer, Julie E. York and Ronald I. Apfelbaum
Craniovertebral instability is a challenging problem in pediatric spinal surgery. Recently, C1-2 transarticular screw fixation in pediatric patients has been used to assist in the stabilization of the craniovertebral joint. Currently there are no data that define the anatomical suitability of this technique in the pediatric population. The authors report their experience in 32 pediatric patients in whom craniovertebral instability was treated by placement of C1-2 transarticular screws.
From March 1991 to October 1998, 32 patients 16 years of age or younger with atlantooccipital, or atlantoaxial instability, or both were evaluated at our institution. There were 22 boys and 10 girls. Their ages ranged from 4 to 16 years (mean age 10.2 years). The most common causes of instability were os odontoideum (12 patients) and ligamentous laxity (nine patients). Six patients had undergone a total of nine previous attempts at posterior fusion at outside institutions.
All patients underwent extensive preoperative radiological evaluation including thin cut (1-mm) computerized tomography scanning with multiplanar reconstruction to evaluate the C1-2 joint space anatomy. Of the 64 possible C1-2 joint spaces in 32 patients, 55 sides (86%) were considered suitable for transarticular screw placement preoperatively. In three patients the C1-2 joint space anatomy was considered unsuitable for screw placement bilaterally. In three patients the anatomy was considered inadequate on one side. Fifty-five C1-2 transarticular screws were subsequently placed, with no resulting neurological or vascular complications. We conclude that C1-2 transarticular screw fixation is technically possible in a large proportion of pediatric patients with craniovertebral instability.
Douglas L. Brockmeyer, Julie E. York and Ronald I. Apfelbaum
with instability at the occipitoatlantal level, atlantoaxial level, or both levels, with regard to the anatomical suitability of C1–2 transarticular screw fixation, and we discuss our approach in determining whether transarticular screw placement is appropriate in a given patient. Clinical Material and Methods From March 1, 1992, to October 1, 1998, 31 consecutive patients who were 16 years of age or youn occipitoatlantal, atlantoaxial, or occipitoatlantoaxial instability were evaluated at Primary Children's Medical Center or The University of Utah Medical
Ronald I. Apfelbaum, Russell R. Lonser, Robert Veres and Adrian Casey
F ractures of the odontoid process of the C-2 VB are common cervical spine injuries, accounting for 10 to 20% of all cervical spine fractures. 9, 16, 20 These fractures most often occur at the junction of the odontoid process and the body of C-2 (Type II) or in the body of C-2 (Type III) and result in atlantoaxial instability. Because of the instability associated with these lesions, patients are at significant risk for immediate or delayed catastrophic spinal cord compromise 12 and achieving spinal stabilization is imperative. Current methods for
comment. First, I think that the best treatment option to offer the majority of patients with recent fractures of the base of the odontoid is direct anterior screw fixation, independently of other factors such as age, sex, direction, degree of displacement on initial x-ray films, other atlantoaxial-associated fractures, or even neurological condition on admission. The presence of absence of displacement and the angulation of the fractured odontoid on the initial x-ray films should not bias the choice of treatment, because this initial position can be modified
Ganesh Rao, Adam S. Arthur and Ronald I. Apfelbaum
T raumatic fractures of the craniocervical junction are associated with a high mortality rate. Postmortem evaluations of victims of high-speed MVAs have suggested an incidence of AO or atlantoaxial injury as high as 21%. 1 Death is typically instantaneous and results from transection of the medulla or spinomedullary junction. Although mortality rates from this injury remain high, more patients are surviving due to on-scene cervical spine stabilization with advanced vehicular extraction techniques. More trauma centers are now using advanced imaging techniques
Sheila K. Singh, Lynda Rickards, Ronald I. Apfelbaum, R. John Hurlbert, Dennis Maiman and Michael G. Fehlings
prior failed atlantoaxial fusion procedure or pseudarthrosis. The most common indications for occipitocervical fusion in the general population include occipitoatlantoaxial instability due to RA, trauma, dens dysplasias, or os odontoideum, Chiari malformation, and Down syndrome. 5, 16, 19, 21, 31–34 Furthermore, occipitocervical fusion is occasionally indicated to revise failed attempts at C1–2 fusion or to manage complex cervical deformities. 11 Reconstruction of the unstable CCJ remains a major challenge, there being no current consensus on the optimal method of
Wayne M. Gluf, Meic H. Schmidt and Ronald I. Apfelbaum
associated with a nonunion rate as high as 30% for C1–2 fusion; however, this incidence improves considerably with the use of a halo orthosis. 5, 10, 12, 15, 18 Transarticular screw placement creates immediate atlantoaxial joint stability and, in contrast to previous posterior wiring/graft constructs, does not require postsurgical brace therapy. The procedure requires surgical precision because serious potential risks are associated with improper screw placement. Thus, despite the very high fusion rate and low associated complication rate reported in the literature, many
To the Editor: I read the article by Gluf, et al. with great interest (Gluf WM, Schmidt MH, Apfelbaum RI: Atlantoaxial transarticular screw fixation: a review of surgical indications, fusion rate, complications, and lessons learned in 191 adult patients. J Neurosurg Spine 2: 155–163, February 2005). The authors have written an excellent and thorough review of atlantoaxial transarticular screw fixation, which is backed by their rich experience. I fully support their remarks and applaud their work. Nonetheless, I would like to comment on their Fig. 3, which may be
Virany Huynh Hillard, Daniel R. Fassett, Michael A. Finn and Ronald I. Apfelbaum
P osterior atlantoaxial fusion is commonly performed with C-1 and C-2 screw fixation and an iliac crest autograft. An autograft is harvested from the posterior iliac crest and wired into position at C1–2. The goal is to achieve a bony fusion because, as with all spinal fusions, the spinal instrumentation may eventually fail unless fusion takes place. Traditionally, autografting has been used for fusion because it provides both an osteoconductive and osteoinductive environment that results in very high rates of fusion. 1 The harvesting of an autograft for