Minimally invasive atlantoaxial fusion.

Department of Neurosurgery, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA.
Neurosurgery (Impact Factor: 3.03). 03/2010; 66(3 Suppl):193-7. DOI: 10.1227/01.NEU.0000366107.69895.74
Source: PubMed

ABSTRACT C1-C2 fusion has significantly advanced from predominantly wiring/cable modalities to more biomechanically stable screw-rod techniques. Minimally invasive surgical techniques represents the most recent modification of atlantoaxial fixation. The indications, rationale, and surgical technique of this novel procedure are described.
Six patients requiring C1-C2 fusion (5 type II odontoid fractures and 1 os odontoideum) underwent minimally invasive C1-C2 fusion over a 2-year period. The cohort consisted of 5 men and 1 woman with a mean age of 51 years (age range, 39-64 y). All 6 patients underwent bilateral segmental atlantoaxial fixation using an expandable tubular retractor.
The mean follow-up time was 32 months (age range, 24-46 mo) There were no intraoperative complications, and the mean estimated blood loss was 100 mL. Solid fusion was achieved in all 6 patients, without pathological motion on dynamic studies. Postoperative computed tomographic images showed no hardware malposition in the scanned patients (4 of the 6 patients).
Placement of C1 and C2 instrumentation using minimally invasive techniques is technically feasible. Because the instrumentation and the means of obtaining arthrodesis do not differ substantively from the standard approach, we would not anticipate long-term results to be different from those of an open procedure, apart from the approach-related morbidity.

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