Total hip replacement (THR) replaces the damaged hip joint with a prosthetic implant. Hip revision surgery becomes necessary when the original implant or its components fail due to reasons like loosening, infection, or wear, requiring a complex operation to replace the compromised parts. There is no fixed, universal limit to how many hip revisions a person can have. Instead, the feasibility of repeated surgery is determined by practical constraints related to the body’s structural capacity and cumulative health risks.
Technical Constraints on Repeated Surgery
The most significant physical limitation on the number of hip revisions is the remaining quantity and quality of the patient’s natural bone. Each subsequent revision procedure is more technically demanding because removing failed components inevitably leads to the loss or damage of additional host bone. This progressive deficiency makes it increasingly difficult for the surgeon to achieve stable fixation for the new prosthetic components.
Severe bone defects are often classified using systems like Paprosky, with Type III and IV defects representing extensive loss of the proximal femur. Surgeons must use specialized techniques, such as extensively porous-coated stems or cortical strut allografts, to bypass these large defects and secure the new implant. The primary goal of any revision is to obtain immediate, reliable stability, but the gradual erosion of the bone compromises this foundation and increases the risk of mechanical failure or periprosthetic fracture.
Cumulative Risks of Subsequent Revisions
Beyond the structural challenges, repeated hip revisions introduce systemic health risks that accumulate with each operation. One of the most serious concerns is the elevated risk of periprosthetic joint infection (PJI), which is a devastating complication. The risk of requiring a re-revision is almost four times higher if the previous surgery treated an infection rather than aseptic loosening. For patients who have undergone multiple previous hip revisions for infection, the re-revision rate can climb to over 40%.
The length and complexity of revision surgery also increase the risk of acute complications. Procedures lasting longer than 120 minutes or involving significant blood loss (over 500 milliliters) are associated with a higher probability of PJI. The average blood loss in septic revisions is notably higher than in aseptic revisions, often exceeding 2,500 milliliters. These extended, complex operations place a greater physical toll on the patient’s body and increase the chances of anesthesia-related complications. The cumulative mortality rate within seven years following a septic revision can be as high as 40%, with the first six months post-operation being the most precarious period.
Patient and Surgical Factors Determining Feasibility
The ultimate decision to attempt another revision is based on an individualized risk-benefit analysis, taking into account several patient and surgical variables. A patient’s overall health status, often quantified by the American Society of Anesthesiologists (ASA) score, is a major consideration, as higher scores are linked to greater risks of complications like PJI. Existing comorbidities, such as diabetes or heart failure, can also significantly increase the likelihood of infection and complicate recovery.
While younger patients are statistically more likely to need a revision of their primary hip replacement, older patients facing a re-revision have a lower hazard ratio for needing subsequent surgery. The quality of the surrounding soft tissue, including the muscles and ligaments, is also considered because poor soft tissue integrity is a leading cause of implant instability and failure. Finally, surgeon experience and the use of modern implant fixation techniques and bearing surfaces play a measurable role in determining the long-term success of the revision procedure.
Alternatives When Revision is Exhausted
When the structural limits of the bone are exhausted or the patient’s health risks become prohibitive, total hip replacement or further revision is no longer a viable option. In these situations, salvage procedures are used, designed to prioritize infection control and pain relief over the restoration of full joint function. The most common of these is the Girdlestone procedure, also known as resection arthroplasty.
This operation involves removing the femoral head and neck, allowing the remaining tissue to form a fibrous scar, known as a pseudoarthrosis. While the Girdlestone procedure eliminates chronic infection and provides pain relief, it results in inevitable leg shortening, typically between 1.5 to 5 centimeters. Patients who undergo this procedure are generally unable to walk without assistance. Another, less common, alternative is hip arthrodesis, which is a fusion of the hip joint that provides a stable, pain-free, but completely immobile joint.