Authors of section

Executive editor

Michael Baumgaertner


Michael Huo, Michael Leslie, Iain McFadyen

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Fracture around loose patellar component and poor bone stock

General considerations

These are extremely challenging fractures because lack of bone of stock is a barrier to reimplantation of the component. Resection arthroplasty is often indicated.

These fractures are classified by UCPF as V.34-B3.

Loose component, poor bone quality


These fractures often occur with no or minimal trauma, including intraoperatively during revision arthroplasty surgery.

Clinical signs

There might be evidence of preceding pain and loss of function.


Plain X-rays remain the first line of investigation.

CT scan can be used to assess the size and position of fragments, implant stability, and bone stock.

Comparison with previous X-rays is useful.

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