Total hip replacement in dogs

Total hip replacement (THR) in dogs represents one of the most significant surgical advancements in modern veterinary orthopedics, offering long-lasting pain relief, restoration of joint function, and a remarkable improvement in quality of life for patients with advanced hip disorders.

In general, total hip replacement is indicated in cases of severe secondary osteoarthritis, end-stage hip dysplasia, irreparable fractures of the femoral head or neck, avascular necrosis, or failure of conservative treatments.

Unlike femoral head and neck excision (FHO), which relies on the formation of a fibrous pseudo-joint and rarely restores full range of motion in large-breed or athletic dogs, total hip replacement re-establishes a joint that is biomechanically close to normal, allowing the dog to return to activities such as running, jumping, and swimming without significant pain.

Preoperative planning begins with orthogonal pelvic radiographs, taken with minimal rotation, to measure femoral anteversion, assess acetabular depth, and determine the correct size of the prosthetic components.

In recent years, CT scanning has become a valuable tool for generating 3D models, which assist in selecting cemented or press-fit acetabular cups and modular femoral stems, helping reduce the risk of postoperative dislocation.

During surgery, the craniolateral approach provides excellent access to the acetabulum. After dislocation and resection of the femoral head, the acetabulum is gradually reamed to accommodate the acetabular component, avoiding excessive loss of ventral coverage, which could predispose to subluxation.

Cementing the cup or impacting the porous component requires strict hemostasis and pulsatile irrigation to remove bone debris that could interfere with adhesion.

On the femoral side, the medullary canal is reamed to a diameter that provides 70%–80% cortical fill for either the cement or the porous stem. The prosthetic collar is aligned with the physiological anteversion (typically 5°–10°). After joint reduction, stability is tested in abduction and internal rotation. Any immediate instability must be corrected intraoperatively by adjusting femoral offset or reinforcing the capsulorrhaphy.

Postoperative care involves multimodal analgesia (opioids, selective NSAIDs, epidural or peripheral nerve blocks) and strict activity restriction for 2 to 3 weeks. Early physiotherapy — including passive range-of-motion exercises and strengthening of the gluteal and quadriceps muscles — accelerates tissue integration and minimizes muscle atrophy. Follow-up radiographs at 30, 60, and 180 days are recommended to monitor for osseointegration or radiolucent lines suggestive of loosening.

Complication rates range from 5% to 15% and include dislocation (most common in the first two weeks), infection, periprosthetic fractures, and micromotion of the acetabular component. Antibiotic prophylaxis is continued for up to 24 hours postoperatively, and owner education about activity restriction is crucial to prevent early rotational trauma.

When well-indicated and properly performed, total hip replacement restores dogs to a nearly pain-free life, with many owners reporting increased energy, willingness to play, and improved athletic performance.

Long-term studies show implant survival rates exceeding 90% at 10 years, comparable to outcomes in human medicine. Therefore, for dogs suffering from refractory pain or severe functional limitations, total hip replacement is not just an alternative — it is often the best definitive solution.

References Fossum, T. W. Small Animal Surgery, 6ª ed., Elsevier, 2023.Roe, S. C.; Markel, M. D. “Total Hip Replacement in the Dog.” Veterinary Clinics of North America: Small Animal Practice, vol. 53, no. 4, 2023, pp. 897-918.