Patella-Femoral Arthroplasty

Indications:

• Isolated PF arthritis.
• Young patients (<50 years).

Contraindications:

• PF instability.
• Medial or lateral compartment arthrosis.
• High-demand patients with false expectations.
• Inflammatory arthritis.
• Malalignment.

Results:

• In appropriate patients, 90% achieve good outcomes at mid-term follow-up.
• Conversion to Total Knee Replacement (TKR):
  • Some reports indicate that outcomes are worse than primary TKR.
  • Early reports (AAOS 2012).

Press Fit Condylar (PFC) Sigma Registry Data

British Data:

• All Brands Cemented Unconstrained Fixed Bearing:
  • Revision rate: 2.62% at 8 years.
• Total PFC Implants:
  • 158,000 PFCs implanted since the registry began.
  • Highest proportion in the UK.
• All Fixed Bearing Implants:
  • Revision rate: 2.04% at 8 years.
• Cemented Posterior Stabilized (PS) PFC:
  • Revision rate: 2.25% at 8 years.
• Cemented Cruciate Retaining (CR) PFC:
  • Revision rate: 1.84% at 8 years.

Swedish Data:

• 10-Year Follow-Up for TKR:
  • Results given as revision rate and risk of revision compared to AGC knee.
• 23,000 PFC Implants over the registry period (most of any TKR).
• Risk of revision for all cemented PFC fixed bearing types:
  • 0.83 below reference (lowest risk of revision of all implants).
• PFC with Patella Resurfacing:
  • Risk of revision ratio: 1.2.
  • Statistically equal to AGC.
  • Better than all other brands.
• Cumulative 10-Year Revision Rate for PFC:
  • 4%, lowest rate (lower than AGC).