Evid Based Spine Care J 2014; 05(02): 112-118
DOI: 10.1055/s-0034-1386749
Case Report
Georg Thieme Verlag KG Stuttgart · New York

To the Occiput or Not? C1–C2 Ligamentous Laxity in Children with Down Syndrome

Kris Siemionow
1   Department of Orthopaedics and Neurosurgery, University of Illinois, Chicago, Illinois, United States
2   Illinois Spine and Scoliosis Center, Chicago, Illinois, United States
Dean Chou
3   The UCSF Spine Center, University of California San Francisco, San Francisco, California, United States
› Author Affiliations
Further Information

Publication History

31 May 2013

03 June 2014

Publication Date:
24 September 2014 (online)


Study Design Retrospective case review.

Objective Atlantoaxial instability with and without basilar invagination poses a considerable challenge in management regarding reduction, surgical approach, decompression, instrumentation choice, and extent of fusion. A variety of strategies have been described to reduce and stabilize cranial settling with basilar invagination. Modern instrumentation options included extension to the occiput, C1–C2 transarticular fixation, and C1 lateral mass–C2 pars among others. Since not all cases of cranial settling are the same, their treatment strategies also differ. Factors such as local vascular anatomy, amount of subluxation, need for distraction, and shape of occipital condyles will dictate level and type of instrumentation. The objective of this study was to outline treatment options and provide a rationale for the surgical plan.

Methods Two cases of C1–C2 instability in patients with Down syndrome are described. Case 2 underwent C1–C2 instrumented fusion, whereas case 1 involved posterior instrumented fusion to the occiput.

Results Both patients tolerated the procedures well. There were no complications. Minimum follow-up was 1 year. There was no loss of reduction. Solid arthrodesis was achieved in both cases.

Conclusion Successful reduction can be achieved with both C1–C2 instrumented fusion as well as O–C instrument fusion. Factors such as local vascular anatomy, amount of subluxation, need for distraction, and shape of occipital condyles will dictate level and type of instrumentation.


This case report is IRB exempt according to the University IRB policy.

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