A tlantoaxial transarticular screw fixation was introduced in 1987 by Magerl and Seemann 12 as biomechanically superior to other techniques for atlantoaxial fusion. The procedure is technically demanding; significant anatomical variations and the inability to obtain intraoperative visualization place the VA at risk for injury. The authors of clinical reports on C1–2 transarticular screw fixation have indicated that screw misplacement occurs in up to 15% of patients, with a 4.1% rate of VA injury. 8, 11 The authors of recent anatomical studies have indicated
Orin Bloch, Langston T. Holly, Jongsoo Park, Chinyere Obasi, Kee Kim and J. Patrick Johnson
John K. Stokes, Alan T. Villavicencio, Paul C. Liu, Robert S. Bray and J. Patrick Johnson
Surgical treatment of atlantoaxial instability has evolved to include various posterior wiring techniques including Brooks, Gallie, and Sonntag fusions in which success rates range from 60 to 100%. The Magerl–Seemans technique in which C1–2 transarticular screws are placed results in fusion rates between 87 and 100%. This procedure is technically demanding and requires precise knowledge of the course of the vertebral arteries (VAs). The authors introduce a new C1–2 fixation procedure in which C-1 lateral mass and C-2 pedicle screws are placed that may have advantages over C1–2 transarticular screw constructs.
A standard posterior C1–2 exposure is obtained. Polyaxial C-2 pedicle screws and C-1 lateral mass screws are placed bilaterally. Rods are connected to the screws and secured using locking nuts. A cross-link is then placed. Fusion can be performed at the atlantoaxial joint by elevating the C-2 nerve root.
The technique for this procedure has been used in four cases of atlantoaxial instability at the author's institution. There have been no C-2 nerve root– or VA-related injuries. No cases of construct failure have been observed in the short-term follow up period.
Atlantoaxial lateral mass and axial pedicle screw fixation offers an alternative means of achieving atlantoaxial fusion. The technique is less demanding than that required for transarticular screw placement and may avoid the potential complication of VA injury. The cross-linked construct is theoretically stable in flexion, extension, and rotation. Laminectomy or fracture of the posterior elements does not preclude use of this fixation procedure.
Naresh P. Patel, Neill M. Wright, William W. Choi, Duncan Q. McBride and J. Patrick Johnson
all patients ALL ossification was noted between C-3 and C-7 ( Fig. 1 upper left ). The most cephalad extent was the inferior aspect of C-2 in two patients. The mean ossified ALL was approximately 1 cm in thickness and caused anterior displacement of the prevertebral soft tissue. Involvement of another spinal region (T8–11) was present in only one patient. On plain radiographs and CT scans small areas of calcification were demonstrated within a defined retroodontoid mass ( Fig. 1 lower ). There was no osseous erosion of the atlantoaxial complex, and the gross
Terrence T. Kim, Doniel Drazin, Faris Shweikeh, Robert Pashman and J. Patrick Johnson
exposure and thyroid nodules . J Res Med Sci 17 : 434 – 438 , 2012 2 Baaj AA , Beckman J , Smith DA : O-Arm-based image guidance in minimally invasive spine surgery: technical note . Clin Neurol Neurosurg 115 : 342 – 345 , 2013 3 Börm W , König RW , Albrecht A , Richter HP , Kast E : Percutaneous transarticular atlantoaxial screw fixation using a cannulated screw system and image guidance . Minim Invasive Neurosurg 47 : 111 – 114 , 2004 4 Castro WH , Halm H , Jerosch J , Malms J , Steinbeck J , Blasius S
Doniel Drazin, Terrence T. Kim, David W. Polly Jr and J. Patrick Johnson
craniovertebral junction, atlantoaxial complex, trauma, and tumor resection. It has recently been applied in large-scale use to degenerative and congenital deformities in the thoracolumbar spine. 5 , 10 , 14 , 16 , 19 Registration The automatic registration process, a major advancement, has allowed IGS technology to be used without necessitating significant surgeon input for this part of the procedure. Previously, the registration process required obtaining a CT scan and either physically or electronically importing the data into the stereotactic IGS workstation so that
Faris Shweikeh, Jordan P. Amadio, Monica Arnell, Zachary R. Barnard, Terrence T. Kim, J. Patrick Johnson and Doniel Drazin
basilar invagination . ORL J Otorhinolaryngol Relat Spec 72 : 91 – 95 , 2010 25 Lee JY , O'Malley BW , Newman JG , Weinstein GS , Lega B , Diaz J , : Transoral robotic surgery of craniocervical junction and atlantoaxial spine: a cadaveric study. Laboratory investigation . J Neurosurg Spine 12 : 13 – 18 , 2010 26 Lieberman IH , Togawa D , Kayanja MM , Reinhardt MK , Friedlander A , Knoller N , : Bone-mounted miniature robotic guidance for pedicle screw and translaminar facet screw placement: Part I—Technical development
orthosis, 2 with a Minerva brace, and 1 with a halo. Two patients required cervical surgery; an occipital cervical fusion for a type 2 odontoid fracture and one atlantoaxial fusion for atlantoaxial instability was performed. At the follow up appointments, none of the patients were found to have delayed instability based on clinical examination, upright x-rays or flexion-extension x-rays. Conclusion: All isolated OCF are likely stable injuries. Our data suggests all isolated OCF may be treated conservatively with any type of cervical orthosis and minimal follow up