Periprosthetic femoral fracture is a major complication that can occur following total hip replacement, the operation of the (previous) century. Before the introduction of the Vancouver Classification System (VCS) in 1995, several other classification systems had been described in the literature1. Nineteen years after the introduction of the VCS, Duncan and Haddad presented the Unified Classification System (UCS)2. Their aim was to create a universal classification system for periprosthetic fractures that was independent of the joint involved or the bone affected and that could replace the VCS. However, as determined in the systematic review by Schopper et al., the VCS remains, to date, the most common universal language for classifying periprosthetic fractures following total hip arthroplasty3. I agree with Duncan and Masri that the VCS has gained widespread acceptance due to the simplicity of the classification itself and the clarity of its guiding principles, such as fracture location, implant stability, and bone quality. Currently, this system represents one of the most widely recognized classification systems in the orthopaedic literature. I congratulate Duncan and Masri on their reassessment and critical appraisal of the continued relevance of the VCS in current practice. Personally, I believe that the strength of their article lies in its reaffirmation of the fundamental principles of the VCS. In their article, the authors highlight an important issue in the current management of periprosthetic femoral fractures. The major strength of the historical VCS was its focus on implant stability. However, it must be noted that the classification system was developed during a time when cemented stems were predominantly used. Loosening is often easier to diagnose on radiographs for cemented stems than for cementless stems, the current gold standard. This may lead to the misclassification of loose stems as stable, as demonstrated in data from the Swedish National Hip Arthroplasty Register4. Stoffel et al. proposed an algorithm to improve the identification of loose stems in patients with a periprosthetic femoral fracture5. Increasing pain or limited mobility prior to the fracture may be indicative of stem loosening. However, in clinical practice, the true diagnosis of stem stability can ultimately only be confirmed intraoperatively. Another important evolution discussed by Duncan and Masri is the retirement of Type-C fractures in the revised classification. This change is related to the confusion that exists among surgeons in distinguishing between Type B1 and Type C. Many surgeons have classified Type-B1 fractures as those proximal to the tip, and Type-C fractures as those at the tip, whereas Type-C fractures were meant to be well distal to the stem. Historically, the treatment strategy was fixation either with 2 cortical strut allografts or with a plate and a strut for Type-B1 fractures, and fixation with a plate for Type-C fractures. As fixation strategies and osteosynthesis implants have evolved over time with the advent of modern locking plates, both fracture patterns have been treated the same, and thus a true distinction is no longer necessary. From this perspective, the authors’ rationale for retiring Type-C fractures is logical, as it reflects the evolution and adaptability of contemporary fixation techniques. However, I believe that maintaining Type-C fractures within the classification system remains important. This fracture pattern forms an important part of the established clinical language about these injuries. In contrast, I support the major modification of the VCS to represent interprosthetic fractures, given their increasing prevalence in recent years. The absence of a formal Type-D category in the revised classification warrants clarification. Within the UCS framework2, a Type-D fracture refers to any fracture around a hip prosthesis in the presence of a knee arthroplasty, regardless of implant stability. Rather than introduce a separate Type-D category, the revised VCS addresses this issue through the important distinction between Type-B1T and B1S fractures. I agree with the authors that a true interprosthetic fracture occurring between the tips of a hip stem and a knee stem is biomechanically similar to a transverse fracture at, or just distal to, the tip of a femoral stem. These fracture patterns are effectively captured within the Type-B1T category, and their treatment principles are identical, typically involving bridging fixation either with a locking plate and a cortical strut or with 2 orthogonal plates. This refinement allows interprosthetic fractures to be appropriately classified and managed without the need for an additional fracture type while maintaining conceptual consistency within the system. Another important aspect in the treatment of periprosthetic fractures is the lack of a standardized treatment algorithm for patients with concomitant periprosthetic joint infection (PJI). The VCS is limited to implant stability, fracture location, and bone loss. However, an increasing number of periprosthetic femoral fractures are occurring in combination with PJI, which is not addressed by the VCS. Epidemiological data have shown that many periprosthetic fractures following total hip arthroplasty are associated with a loose stem. There is an approximately 8% incidence of indolent infection in cases of presumed aseptic loosening6. The coexistence of these 2 complications represents one of the greatest challenges in complex revision arthroplasty and needs a separate focus, but this can be thought of within the context of PJI management. In summary, the VCS remains the most widely used classification system in the orthopaedic community and is likely to continue as the dominant method in the 21st century.
Mustafa Citak (Wed,) studied this question.