Development of a Customized Interbody Fusion Device for Treatment of Canine Disc-Associated Cervical Spondylomyelopathy.

Abstract

OBJECTIVES:  The main purpose of this study was to design, manufacture and implant a customized three-dimensional (3D) printed, intervertebral spacer to treat disc-associated cervical spondylomyelopathy (DACSM) in dogs. This study also used advanced imaging to assess implant movement, subsidence and interbody fusion. ANIMALS:  Two client-owned dogs with DACSM. METHOD:  Customized interbody devices were designed and 3D printed in titanium alloy. The devices were implanted in dogs diagnosed with DACSM. The dogs were evaluated at time points 0, 2 and 6 months to determine clinical outcome, degree of interbody fusion, implant migration and subsidence. RESULTS:  Progressive fusion was noted across the affected intervertebral space by 6 months. Implants mildly shifted cranially in the 2-month interim. There was no subsidence of the intervertebral device through the vertebral end plates in dog 1 and minimal in dog 2 (∼0.5 mm). Clinically, the neurological status improved in both dogs. CONCLUSIONS:  The customized interbody devices restored the intervertebral space and resulted in a degree of interbody fusion and resolution of clinical signs. CLINICAL SIGNIFICANCE:  This report illustrates preliminary outcomes of DACSM treated with a customized, end plate conforming, intervertebral device. Collaboration between clinicians and engineers with advanced manufacturing technologies can provide a cutting-edge standard of care for patients suffering from DACSM.