Use of three‐dimensionally printed β‐tricalcium phosphate synthetic bone graft combined with recombinant human bone morphogenic protein‐2 to treat a severe radial atrophic nonunion in a Yorkshire terrier

Abstract

Objective: To describe a novel surgical approach to treat a critical-sized bone defect due to severe, radial atrophic nonunion in a miniature dog. Study design: Case report Animal: A 1-year-old Yorkshire terrier with a critical-sized left radial defect after failed internal fixation of a transverse radial fracture. Methods: Computed tomographic (CT) images of the radius were imported for three-dimensional (3D) printing of a custom-designed synthetic 3D-printed β-tricalcium phosphate (β-TCP) scaffold. The radius was exposed, and the β-TCP scaffold was press-fitted in the bone gap underneath the plate. Recombinant human bone morphogenic protein-2 (RhBMP-2) collagen sponges were squeezed to soak the scaffold with growth factor and then placed on both sides of the synthetic graft. Two additional cortical screws were also placed prior to routine closure of the surgical site. Results: Radiographic examination was consistent with complete healing of the radius defect 4 months after surgery. The bone plate was removed 10 months after surgery. According to CT examination 18 months after surgery, there was no evidence of the synthetic graft; instead, complete corticalization of the affected area was noted. Complete functional recovery was observed until the last clinical follow-up 36 months postoperatively. Conclusion: Screw fixation and use of a 3D-printed ceramic scaffold augmented with rhBMP-2 resulted in excellent bone regeneration of the nonunion and full recovery of a miniature breed dog. Clinical significance: The therapeutic approach used in this dog could be considered as an option for treatment of large-bone defects in veterinary orthopedics, especially for defects affecting the distal radius of miniature dogs.

Delayed union, non‐union and mal‐union in 442 dogs

“…The significantly ( P < 0.05) greater proportion of Yorkshire terriers with non‐union appears to be spurious as this was not found for delayed union, or when delayed and non‐union were combined. It is often stated that toy breed dogs with fractures of the radius and ulna are at increased risk of delayed and non‐union, 26,27 but the evidence for this appears weak, and our results do not support it. Recent advances in fracture fixation techniques may have improved outcomes for radius and ulna fractures in toy breed dogs.…”

Active Materials for 3D Printing in Small Animals: Current Modalities and Future Directions for Orthopedic Applications

“…Three-dimensional-printed β-TCP scaffold combined with recombinant human bone morphogenic protein-2 were used to manage severe atrophic nonunion of the radius in a Yorkshire terrier. The results showed excellent bone regeneration and complete functional recovery [71].…”

Three-Dimensional Osteogenic Differentiation of Bone Marrow Mesenchymal Stem Cells Promotes Matrix Metallopeptidase 13 (MMP13) Expression in Type I Collagen Hydrogels

“…Some research groups have also experimented with the in vitro addition of recombinant MMPs and BMPs to enhance matrix remodeling and mineralization capabilities of BMSCs [42][43][44]. Similarly, the addition of recombinant platelet derived growth factor, basic fibroblast growth factor (bFGF), and vascular endothelial growth factor to increase the angiogenic potential, has been considered a promising method to induce osteogenic differentiation [45].…”