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.

Development of a lumbosacral intervertebral cage prototype for dogs

“…The 3DS MAX 2015 software allowed designing two cage models according to the contour of the bone surfaces and the intervertebral space size. In the future, these cage models can be adapted and reshaped to better fit the L7-S1 segment, since 3D technology is widely used in human medicine and is promising in veterinary medicine for facilitating surgical planning and improving research (Hespel et al 2014, Joffe et al 2019. To measure disc space, radiography should be used with caution, as CT better delineates the contact areas between the endplate and the cage, with more reliable measurements.…”

Mapping Subchondral Bone Density Distribution in the Canine C6-C7 Vertebral Endplates: A CT-OAM Study

“…Its incidence in humans is reported to range from 0% to as high as 83%, with a mean rate of 21.1% [14]. In the context of dogs, studies have documented cage subsidence across a wide spectrum, with incidence rates spanning from 11% to 100% in treated spinal articulations [3][4][5][8][9][10][11][15][16][17][18][19]. Among these investigations, a consistent finding is that the cranial endplate of the caudal vertebra is the most commonly affected site.…”

“…Custom-designed cages have previously demonstrated success in dogs with DA-CSM [18,19]. The enhancement of these designs primarily revolved around molding the cage to closely match the curvature of the cranial and caudal endplates.…”

Biomechanical effects of a titanium intervertebral cage as a stand‐alone device, and in combination with locking plates in the canine caudal cervical spine

“… 12 , 14 Surgery comprises a direct decompressive technique, for example, dorsal laminectomy or ventral slot, 14 , 15 , 16 or distraction‐stabilization techniques, addressing the dynamic component of CCSM. 2 , 4 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33…”