Revision of Total Hip Arthroplasty

Kenneth A. Johnson, MVSc, PhD, FACVSc, DACVS, DECVS

A successful outcome after total hip arthroplasty (THA) restores pain-free mobility for the canine and feline patient and is equally welcomed by the owner and the surgeon. An uncomplicated outcome can be expected in more than 90% of canine THA procedures. However, despite improvements in implant design, and all aspects of THA implantation surgery, intraoperative and postoperative complications will usually require revision surgery.

The successful revision of a failed THA is predicated on the surgeon having a good understanding of the cause of the complication. This concept is exemplified in a case reported in this issue of the Journal; greater trochanteric fracture and acetabular component loosening were precipitated by polyethylene wear particle-induced osteolysis, which in turn allowed luxation of the THA.[1] The polyethylene particles were generated by wearing of the bearing surface of the acetabular component liner.

The most common cause of long-term THA failure in humans is aseptic loosening, in the absence of infection.[2] Wear debris is the most important factor in the development of this aseptic loosening.[2] Wear debris within a critical size range (∼0.2–0.8 μm) has been shown to activate human macrophages and osteocytes, which can result in a proinflammatory response, osteoclastogenisis and localized bone resorption or osteolysis.[3] Wear particles of ultra-high molecular weight polyethylene have long been implicated as being a major cause of this problem. Various modifications in the manufacturing process of the polyethylene used in joint prostheses have reduced, but not eliminated, the severity of long-term wear of THA implants. More recently, studies of periprosthetic tissue recovered during the revision of failed total hip and knee joint arthroplasties in human patients have also isolated a range of high-density materials including polymethylmethacrylate, zirconium dioxide, titanium alloy, cobalt chromium alloy, and stainless steel.[2] However, the potential contribution of these high-density particles in the activation of the osteolytic pathway has not been fully elucidated yet.

The wearing of both the polyethylene and the metal-back of acetabular component by the femoral head has been recognized in some canine THA patients. This complication may develop so rapidly that the femoral head perforates through the medial bone wall into the pelvic canal before the problem becomes clinically evident. The reason for this rapid wearing of the acetabular component is not well understood.

Based on some recent sales data provided by THA manufacturers, the number of canine THA procedures performed annually is growing quite quickly. Continued improvements in implant design, surgeon training, case selection, and surgical planning and execution are desirable to minimize the rate of THA revisions. However, the need for THA revision surgery is likely to be a reality for THA surgeons. The development of surgical techniques for THA revision should be supported by clinical evidence. The number of publications reporting such data relating to canine and feline THA are few, so there is a need for prospective multicenter outcome studies of the management of this clinical problem.

Publikationsverlauf

Artikel online veröffentlicht:
15. Juli 2025

• References

• 1 Bassanino J, Guiot LP. Revision of hip luxation in a canine total hip replacement caused by a greater trochanteric fracture secondary to an inflammatory granuloma. Vet Comp Orthop Traumatol 2024; 38 (04) 200-206
• 2 Stratton-Powell AA, Williams S, Tipper JL, Redmond AC, Brockett CL. Mixed material wear particle isolation from periprosthetic tissue surrounding total joint replacements. J Biomed Mater Res B Appl Biomater 2022; 110 (10) 2276-2289
• 3 Ingham E, Fisher J. The role of macrophages in osteolysis of total joint replacement. Biomaterials 2005; 26 (11) 1271-1286