Vancouver Classification of Periprosthetic Femoral Fractures

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The classification uses the fracture location relative to the femoral stem and the fixation status of the implant. Every examiner expects you to recite the full scheme and then state the two key treatment questions: is the stem fixed or loose, and is the bone stock adequate.

Type A fractures involve the trochanteric region. They are subdivided into AG (greater trochanter) and AL (lesser trochanter).

Type B fractures are the most common and the most examined subtype. The fracture line originates at or within a few centimetres of the stem tip. The B1/B2/B3 distinction determines whether the surgeon fixes the fracture around the existing stem or revises the entire femoral component.

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Radiographic assessment of stem stability (before deciding B1 versus B2):

For cemented stems: look for cement mantle fracture, new radiolucent lines at the cement-bone or stem-cement interface, stem subsidence or change in position, and stem-cement debonding.

For cementless stems: look for stem subsidence (compare to immediate post-operative films), change in alignment or varus migration, new radiolucent lines at the bone-prosthesis interface, broken fixation screws if present, and loss of initial osseointegration.

Type B1 — well-fixed stem, adequate bone:

Open reduction and internal fixation. The standard construct is a lateral proximal femoral locking plate combined with unicortical screws and cables around the proximal fragments to avoid perforating the stem. Cortical strut allograft augments the construct and accelerates healing. The approach requires full exposure of the fracture with the stem left in situ. Weight-bearing is protected until union is confirmed.

Type B2 — loose stem, adequate bone:

Revision arthroplasty to a long-stem (or fluted tapered) femoral component that bypasses the fracture by at least two cortical diameters. The old stem and cement are removed, the fracture is reduced, the long stem is cemented or press-fit distal to the fracture, and proximal cables or a plate may supplement fixation. The long stem acts as an internal splint stabilising the fracture while achieving durable implant fixation.

Type B3 — loose stem, poor bone stock:

Revision arthroplasty with structural bone augmentation. Options include: impaction bone grafting with a long-stem prosthesis, an allograft-prosthesis composite (APC) using a femoral allograft with a cemented stem inside it, or a megaprosthesis (tumour-type endoprosthetic replacement) when bone loss is so severe that no other option will achieve stability. The choice depends on the extent of proximal bone loss, patient age, activity level, and expected survival.

Type C fractures occur well distal to the femoral stem tip, typically in the supracondylar or distal femoral region. The arthroplasty stem is stable and irrelevant to the fracture management.

The fracture is treated as a native femoral fracture. Options include a retrograde intramedullary nail (if the distal fragment is long enough and the canal geometry permits) or a distal femoral locking plate. The nail must avoid the stem tip — there should be sufficient intact femur between the stem tip and the fracture for stable fixation.

Classification requires systematic imaging and clinical workup before the patient reaches theatre.

• Radiographs: AP pelvis, AP and lateral femur of the affected side, and the contralateral side for comparison. Include full-length films from hip to knee. Compare with all previous post-operative radiographs.
• CT scanning: Helpful for assessing fracture configuration, cortical bone stock, cement mantle integrity, and detecting subtle loosening not visible on plain film. Standard for pre-operative planning in B-type fractures.
• ** templating:** Plan for the longest stem you may need. If there is any chance the fracture is B2, have a long fluted tapered stem and revision instruments available before you start.
• Medical optimisation: These patients are typically elderly with multiple comorbidities. Coordinate with geriatric medicine, cardiology, and anaesthetics. Early surgery (within 24 to 48 hours) reduces morbidity, but the physiological priority is a safe patient.
• Bone graft and allograft availability: For B3 and selected B2 fractures, arrange proximal femoral allograft, morsellised cancellous bone for impaction grafting, or megaprosthesis availability before listing for theatre.
• Intra-operative imaging: Fluoroscopy is essential. You will need AP and lateral views of both the hip and the femur to confirm reduction, stem position, and hardware placement.

• Inter-observer reliability is moderate for B-subtyping. The B1 versus B2 distinction depends on interpreting stem stability from radiographs, which is imperfect. Two surgeons reviewing the same films may disagree whether a stem is loose, which is why intra-operative testing is standard practice.
• The classification does not address fracture pattern (spiral, transverse, comminuted) or the quality of the proximal femoral bone in sufficient detail. Pattern and comminution affect fixation choice within each subtype but are not captured by the letter.
• Cementless taper designs can develop fibrous stable fixation that is not radiographically loose but is not osseointegrated. Whether this counts as well-fixed or loose for classification purposes is debated and affects B1 versus B2 treatment.
• The incidence of periprosthetic femoral fracture is rising as the ageing population expands, implant survivorship increases, and patients outlive their prostheses. Modern registries report it as one of the leading causes of revision in the second decade after arthroplasty.
• The classification was designed for cemented stems and extrapolated to cementless implants. Most modern series include a mix, but the radiographic criteria for loosening differ between the two, and the original validation studies predate widespread cementless use.
• B3 bone-loss assessment is subjective. The threshold at which adequate bone (B2) becomes poor bone (B3) is not precisely defined and varies between surgeons and centres.