Object: Rigid occipitocervical instrumentation for craniovertebral instability is gaining widespread acceptance for use in pediatric patients; however, most of the instrumentation has been modified from adult-sized hardware. The Wasatch loop system (formerly the Avery-Brockmeyer-Thiokol loop system) is a rigid occipitocervical fixation device designed specifically for use in children. It affixes to the occiput and incorporates either C1-2 transarticular screws or C-2 pars screws. It is preformed and is available in a variety of sizes. The authors describe their clinical experience and long-term follow-up experience with the first 22 patients.
Methods: An institutional review board-approved retrospective review of medical records and radiographs was performed for patients who underwent occipitocervical fusion with the Wasatch loop. The mean patient age was 4.9 years (1.2-13 years), and the overall mean follow-up was 4 years (1.5-6.5 years). Six patients had posttraumatic instability, and 16 patients had congenital instability.
Results: Twelve patients underwent placement of bilateral C1-2 transarticular screws, 6 patients had placement of a combination of C1-2 transarticular and C-2 pars screws, and 4 patients had placement of bilateral C-2 pars screws. One patient required a halo orthosis; the others were treated postoperatively with a hard cervical collar. All patients had radiographic evidence of solid occipitocervical arthrodesis on last follow-up examination.
Conclusions: The Wasatch loop system is a novel internal fixation device for children who have posttraumatic or congenital occipitocervical instability. Successful arthrodesis was achieved in all patients with minimal use of halo orthoses.