3D printing in experimental orthopaedic surgery: do it yourself

Eur J Orthop Surg Traumatol. 2019 Jul;29(5):967-973. doi: 10.1007/s00590-019-02415-5. Epub 2019 Mar 12.

Abstract

Introduction: Periprosthetic infection is considered an increasing incidence pathology whose therapeutic strategies can be defined as unsatisfactory. Currently, animal models are employed to study its physiopathology and strategic therapies, but non-species-specific materials are implanted as foreign bodies. The use of these implants implies intrinsic instability, which hinders the development of a biofilm on their surfaces and complicates the post-operative recovery of the animal. The objective of the present study is the design of a species-specific implant for the New Zealand white (NZW) rabbit by means of 3D printing.

Materials and methods: A CT scan of the knee of a NZW rabbit was performed, and the tibial surface was reconstructed in order to fabricate a species-specific tibial plateau using Horos® and Autodesk® Meshmixer™ software. This implant was inserted in fifteen NZW rabbits, and the assessment of its stability was based on the position of the limb at rest and the animal weight-bearing capacity. Biofilm formation on the surface was demonstrated by crystal violet staining.

Results: A 1.81 cm × 1 cm × 1.24 cm stainless steel implant was designed. It consisted of a 4-mm-thick tibial plate with a rough surface and an eccentric metaphyseal anchoring. All of the animals exhibited hyperflexion of the operated limb immediately post-operative, and 100% could apply full weight bearing from day 5 after surgery.

Conclusions: The species-specific design of implants in experimental surgery encourages rapid recovery of the animal and the development of a biofilm on their surfaces, making them ideal for the study of the physiopathology and for establishing possible therapeutic targets for prosthetic infection.

Keywords: 3D printing; Animal model; Implant; Periprosthetic joint infection.

MeSH terms

  • Animals
  • Arthroplasty, Replacement, Knee / instrumentation*
  • Arthroplasty, Replacement, Knee / methods
  • Bone Plates*
  • Computer-Aided Design*
  • Knee Joint* / diagnostic imaging
  • Knee Joint* / surgery
  • Knee Prosthesis*
  • Models, Anatomic
  • Models, Animal*
  • Plastic Surgery Procedures / adverse effects
  • Plastic Surgery Procedures / methods
  • Printing, Three-Dimensional
  • Prosthesis Design / methods*
  • Rabbits
  • Tibia / surgery