Zurich Mini Cementless Total Hip Replacement in Cats: Specific Considerations and Short-Term Outcomes in 11 Cats (17 Hips)

Abstract Total hip replacement (THR) in cats remains uncommon due to species-specific anatomical features, including limited acetabular retroversion, mismatch between femoral canal and acetabular size, and technical difficulty during femoral preparation related to sclerosis secondary to slipped capital femoral epiphysis (SCFE), the main indication in this species. These factors complicate implant selection, canal preparation, and cup orientation. This retrospective study reports clinical and radiographic outcomes of 17 cementless Mini THR procedures performed in 11 cats (nine Maine Coons and two Domestic Shorthairs) between 2022 and 2025. Indications included SCFE (n = 11), hip dysplasia (n = 5), and femoral neck fracture malunion (n = 1). Intraoperative fluoroscopy was used to optimize cup positioning. Two intraoperative complications occurred, consisting of minimal cortical fissures stabilized with prophylactic cerclage wires. Postoperative complications included two femoral fractures (11.8%), one resulting in limb amputation. One traumatic hip luxation occurred 10 months after surgery and was considered unrelated to the procedure. At 8 weeks, all remaining implants were pain-free, stable, and showed complete or advanced osteointegration. With careful planning, intraoperative imaging, and appropriate postoperative management, THR can provide excellent short-term outcomes in cats, although limited implant modularity may restrict optimal fit in some patients.