Augmentation with transcortical wiring of an onlay-type prosthesis for a deficient patella during revision total knee arthroplasty

The management of patellae with a severe bony deficiency during revision total knee arthroplasty is a challenging problem. However, using a technique of augmentation with transcortical wiring of an onlay-type prosthesis allowed the authors to revise a deficient patellae successfully. After making the decision to revise the existing patellar component, the procedure was found to be technically straightforward. Furthermore, the procedure does not require sophisticated instruments, only an onlay-type prosthesis, cement and wires. This technique entails fixing wires to the three pegs of the patellar component, passing the wires through drill holes in the anterior cortex and, after compression of a cemented prosthesis, augmenting the fixation by twisting the wires anteriorly. We believe that stable fixation and painless articulation will be obtained with the described technique for deficient patellae.