The Evolution of Implants in Veterinary Orthopedics
Written by Nina R. Kieves, DVM, DACVS-SA, DACVSMR (Canine)
The first use of orthopedic implants in veterinary medicine is not well documented. Significant development of veterinary specific implants began in the mid-20th century. With the increased value placed on companion animals and the growth of veterinary medicine as a profession, more attention was given to treating musculoskeletal issues in animals. This led to the introduction of orthopedic implants specifically designed for animals. This timeframe mirrors a time of large growth in the field of human orthopedics, particularly after World War II, where there were rapid advancements in surgical techniques and implant technology. These advancements eventually began to influence veterinary medicine. Prior to this, veterinary medicine focused on treating infections and disease with surgery being rare and limited to simple procedures with much of the focus being on horses rather than what we consider our pets or companion animals today.
Early implants were often adaptations of available human orthopedic devices. One of the earliest forms of implants used in both human and veterinary orthopedics were bone plates and screws. These were initially simple metal plates attached to bones with screws to stabilize fractures. Another early type of implant was the intramedullary pin. These pins were inserted into the medullary cavity of long bones to provide internal support for fractured bones. While these types of implants have changed significantly since their introduction, they are still commonly used today for fracture repair in human and veterinary medicine.
Over time, veterinarians and researchers recognized the need for species-specific implant designs due to differences in anatomy, size, and biomechanics among various animals. The development of veterinary orthopedic surgery and its implants was influenced by the availability of materials, surgical techniques, and the evolving understanding of animal anatomy and biomechanics. The field has seen significant advancements since these early implants, with current technologies including highly specialized, species-specific, and even custom-made implants for a wide range of orthopedic issues in animals. The latter part of the 20th century and the early 21st century saw significant technological advancements with materials like stainless steel, titanium, and biocompatible polymers becoming common.
While not among the first implants developed for veterinary medicine, one significant milestone in veterinary orthopedic implants was the development of total hip replacement (THR) surgery for dogs. The first THR in a dog was performed in 1957, marking the beginning of a transformative era in veterinary orthopedics. Since then, the technology and techniques have evolved, offering improved quality of life for animals suffering from hip joint issues. Total hip replacement involves replacing both the ball (head of the femur) and socket (acetabulum) of the hip joint with prosthetic implants. The prosthetic ball is typically made from a cobalt-chromium metal alloy, and the socket from high molecular weight polyethylene plastic. These implants are held in place using special bone cement, or are cementless and press fit into the bone.
THR in dogs is a surgical procedure designed to alleviate pain and restore normal joint function in cases of hip dysplasia, traumatic hip luxation, fractures of the femoral head or neck, or avascular necrosis of the femoral head leading to arthritis that cannot be well managed with medical treatment. Today, total joint replacement, particularly THR is commonplace. It is even performed in cats. There are also implants available for partial elbow resurfacing, total elbow replacement, total knee replacement, and total ankle replacement, though these are less commonly performed than THR.
In the commercial space, companies like BioMedtrix (BioMedtrix Whippany, NJ) have played a crucial role in the development of veterinary orthopedic implants. BioMedtrix has over 36 years of experience in developing human and veterinary implants, with several patented designs for the canine hip, knee, elbow, and trauma. They introduced the CFX® (Cemented Fixation) total hip system in 1990 and the BFX® (Biologic Fixation) in 2003. Other implants systems are available for THR including the Kyon Zurich Cementless Total Hip Replacement system (Kyon AG, Zurich, Switzerland) the Helica TPS system (Innoplant Medizintechnik GmbH, Hannover, Germany). Which implant system is used for total joint replacement, or fracture repair, is at the surgeons discretion and may include considerations such as geographic location (not all implants are available in all locations), and most importantly, surgeon comfort level and training with specific implant systems.
In more recent decades, mirroring human orthopedic surgery, veterinary orthopedics has began adopting minimally invasive techniques, such as arthroscopy, leading to faster recovery times and reduced complications. Today, the advent of 3D printing technology has revolutionized veterinary orthopedics. Custom implants and surgical guides can be created for individual animals based on their specific anatomical needs, improving the efficacy of surgeries. This includes custom total joint implants and patient specific plates for fracture repair or corrective osteotomy for angular limb deformities. Ongoing research in biomechanics, material science, and surgical techniques continues to advance the field. There's a growing focus on improving the longevity and biocompatibility of implants, as well as developing regenerative medicine techniques to complement traditional surgical approaches.
The field of veterinary orthopedics continues to evolve, with ongoing research and development. This is evident in the advancements in implant technology, surgical techniques, and postoperative care, significantly improving the outcomes for animals undergoing these procedures. Today, we can offer state of the art surgery to improve our patient’s well-being and mobility due to the technological advances in implants available.
References
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