Micro Total Hip Replacement for Dogs and Cats: Surgical Technique and Outcomes

Objective To describe the surgical technique for the micro total hip replacement (Micro THR) system and report clinical outcomes. Study Design Prospective study. Animals Dogs (n=49) and cats (n=8) with coxofemoral arthropathy. Methods Small breed dogs and cats with coxofemoral arthritis were enrolled for Micro THR. Patient data were recorded. Implant positioning and cement mantle quality were evaluated radiographically. Orthopedic examinations and client interviews were used to assess outcome. Results Micro THR was performed unilaterally (40 dogs, 8 cats) and staged bilaterally (9 dogs) to resolve pain associated with osteoarthritis or trauma. Mean body weight was 7.2 kg. Postoperative complications included prosthesis luxation (9), cup aseptic loosening (1), and sciatic neurapraxia (1). Mean radiographic follow up was 96.1 weeks; 10 joints were followed for >= 3.0 years. Sixty of the 66 (91%) Micro THRs had excellent outcomes. Two dogs (< 2.75 kg) were too small for the prosthesis and 4 dogs with unmanageable luxation had explantation. Conclusions Micro THR is considered a satisfactory procedure for management of small breed dogs and cats with coxofemoral disease unresponsive to medical management. Clinical Relevance Micro THR is a viable option to treat disabling disorders of the hip. More than 170 cat and small dog breeds, and many mixed breeds, could benefit from Micro THR surgery.