By continuing your visit to this site, you accept the use of cookies for the proper management of your account and your subscriptions.

Search

Follow us on social media :

Published in N°276 - August/September 2018
Article viewed 79 times

Patella Infera in TKA

By David Dejour, Yves Malemo, Guillaume Demey in category FOLLOW-UP
Lyon Ortho Clinic, 29B avenue des sources, 69009 Lyon

Patella infera (or patella baja) described by Caton, Deschamps et al in 1982, and then by Noyes in 1991, is defined by a patellar index less than or equal to 0.6.1,2 It can be congenital and is therefore not pathological or acquired leading to characteristic symptoms.

1- Introduction

Patella infera (or patella baja) described by Caton, Deschamps et al in 1982, and then by Noyes in 1991, is defined by a patellar index less than or equal to 0.6.1,2 It can be congenital and is therefore not pathological or acquired leading to characteristic symptoms. 

This rare disorder is sometimes found in the context of total knee arthroplasties (TKAs), thereby aggravating the final outcome. Therapeutic solutions are fairly limited, and the results are sometimes disappointing.

The aim of this article is to review the causes of patella infera after TKA and the therapeutic options. Finally, we will suggest a unique surgical technique.

 

2- Radiological measures of the patellar height

Several radiological indices measuring patellar height have been described. The three most widely known indices include the Caton–Deschamps index, the Blackburne–Peel index and the Insall–Salvati index (Image 1).

Image 1: (A) Caton–Deschamps index (y/x or AT/AP); (B) Blackburne–Peel index (y/x); (C) Insall–Salvati index (y/x)

 

The Caton–Deschamps index was described in 1982. The AT/AP ratio is the ratio between the length of the patellar joint surface (AP) and the distance between the lower edge of the patellar joint surface to the anterosuperior edge of the tibia (AT). It is...

Content only available to subscribers

Subscribe