The Use of Translaminar Subaxial Cervical Screws in Complex Cranio-Cervical Malformations: Two Cases and Review of the Literature

Abstract

Introduction In complex cervical malformations, sometimes we need to make long occipitocervical fusions, even in children. Fixation techniques include the use of wires, hooks, and screws. In C1–C2 instability, we might choose transarticular screws. All these techniques have life-threatening complications and require wide surgical expertise. In complex craniocervical malformations anatomical variations may play a significant role in complications, the safest method to avoid vascular or neurological complications in these cases is yet to be determined. Translaminar screws were first described in the C2 posterior arch as a safe way to place C2 screws and their use has extended to the subaxial spine. In complex malformations, we might find anatomical variations that play to our advantage when using this technique, such as very wide laminas in complex fused vertebral blocs. Aim The aim of this study is to report the use of cervical subaxial translaminar screws in patients with complex craniocervical deformities and review the literature. Patients and Methods We present two female patients with complex craniocervical malformations. The first case is a 21-year-old girl with basilar invagination, posterior occipital malformations, and a type II Chiari who arrived to the ER with a transitory hemiparesia and was deemed hysteric. The second patient is a 13-year-old girl who was referred to us with a mild scoliosis. On further examination, we found a complex Klippel–Feil syndrome, cervicothoracic dysgraphia without meningocele, basilar invagination, type II Chiari, and other symptoms that made us consider a genopathy, still being studied. Both girls presented altered dynamic-evoked potentials. Both patients underwent posterior cervicomedullary decompression and occipitocervical fusion, with subaxial translaminar screws. In the younger girl, C1 posterior arch resection was also necessary. Results Both the patients are asymptomatic and with no complications to report at last follow-up. Discussion Published case series have reported the use of axial and subaxial translaminar screws in atlantoaxial instability, to our knowledge, there have been no reports of their use in complex craniocervical malformations. Conclusion Translaminar screws are a good alternative for subaxial cervical spine fixation in patients with complex occipitocervical malformations. We need longer follow-up and prospective studies to reach further conclusions. Trauma