Authors of section

Executive editor

Michael Baumgaertner


Michael Huo, Michael Leslie, Iain McFadyen

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Fracture around loose patellar component and good bone stock

General considerations

These fractures are challenging to treat because the revision of the component with fracture fixation is difficult to achieve.

These fractures are classified by UCPF as V.34-B2.

Loose component, good bone quality


Fall onto flexed knee.

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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