Abstract
Background Occipitoatlantoaxial malformation (OAAM) is reported rarely in dogs and few treatment
options are described. The congenital condition is thought to be associated with a
proatlas re-segmentation failure resulting in malformation and malalignment of the
craniovertebral junction which can result in C1 to 5 myelopathic signs.
Methods Customized three-dimensional printed locking plate with trajectory screw implantation
points for the stabilization of the atlantoaxial joint in a dog with OAAM. The dog
was evaluated at time points 0, 2, 6 and 9 months to determine clinical outcome, degree
of fusion, implant positioning and subsidence.
Results New bone formation was noted 9 months after surgery, but complete fusion remained
absent, although no implant failure occurred. Clinically, the dog made a good recovery
and was able to exercise normally 9 months after surgery. The only residual deficit
was a subtle left-sided cervical torticollis.
Clinical Significance This report illustrates a management option and outcome of a dog treated with OAAM.
Collaboration between clinicians and engineers provides a new dimension of care for
patients with vertebral malformations.
Keywords
three-dimensional printed locking plate - patient-specific implant design - cervical
vertebral malformation - canine occipitoatlantoaxial malformation
