Craniocervical fusions in children.

The surgical management of craniovertebral junction (CVJ) instability in pediatric patients presents unique challenges. As compared with the adult patient, the anatomical variations of the CVJ in the pediatric patient are significant, complicate the approach, and limit the use of internal fixation. Diminutive osseous and ligamentous structures and syndromic craniovertebral abnormalities complicate the issue. Advances in imaging analysis and instrumentation have improved the armamentarium for managing the pediatric patient who requires craniocervical stabilization. In this paper, the author's experience of performing more than 850 pediatric CVJ fusions is reviewed. This work includes the indications for atlantoaxial arthrodesis and occipitocervical fusion. Early atlantoaxial fusions were performed using interlaminar rib graft fusion, and more recently using either transarticular screw fixation in the older patient, or lateral mass screws at C-1 and rod fixation with either C-2 pars interarticular screw fixation or pedicle screw fixation. A C-2 translaminar screw fixation is also described. Occipitocervical fusions are performed with rib grafts in patients younger than 6 years of age. Subsequently, above that age, contoured loop fixation was performed, and in the past 8-10 years, screw and rod fixation was used. Abnormal spine growth was not observed in children who underwent craniocervical stabilization below the age of 5 years (clearly the bone grew with the patient). However, no deleterious effects were noted in the children treated with rigid instrumentation. The success rate for bone fusion alone was 98%. The author's success rate with rigid instrumentation is nearly 100%. A detailed review of the technique of fusion is presented, as well as the indications and means of avoidance of complications, their prevention, and management.