Abstract
The first isolated patello-femoral (PF) joint arthroplasty (PFA) was a patella cap, a Vitallium shell replacing the patella and maintaining the native trochlea, proposed in 1955 by McKeever. The first PFAs replacing entire PF joint had an inlay design and came in the 1979 with the Richards and Lubinus prosthesis. In the last 20 years, I preferred the onlay PFAs, using the inlay designs only in few selected cases. Onlay prostheses completely resect the trochlea with an anterior cut similar to the one performed for total knee arthroplasty (TKA). The Avon (Stryker) and the Zimmer PFJ are examples of onlay prostheses. Second-generation PFAs allow a correction of trochlea rotation or dysplasia and are associated with good results at short-term and midterm follow-up [1]. The enhanced knowledge on PF kinematics, the higher number of component sizes available, the better surgical instrumentation and the easier surgical technique contributed to improve the results. Moreover, early complications like patellar maltracking, instability or catching and snapping of the patellar component during knee flexion were significantly reduced.
Highlights
The first isolated patello-femoral (PF) joint arthroplasty (PFA) was a patella cap, a Vitallium shell replacing the patella and maintaining the native trochlea, proposed in 1955 by McKeever
PFA in PF osteoarthritis (PFOA) secondary to patellar instability needs a kinematic alignment in which the lateral border of the trochlea is elevated, the lateral trochlear inclination is restored, but the trochlear line remains in partial external rotation
The anterior cut should be perpendicular to the sagittal axis of the kneevjoint and the prosthesis should replace the trochlea without modifying its anatomy and orientation
Summary
The first isolated patello-femoral (PF) joint arthroplasty (PFA) was a patella cap, a Vitallium shell replacing the patella and maintaining the native trochlea, proposed in 1955 by McKeever. The first PFAs replacing entire PF joint had an inlay design and came in the 1979 with the Richards and Lubinus prosthesis. Firstgeneration PFAs had important limitations and poor outcomes These PFAs were inserted in the native trochlea, replacing the articular cartilage and leaving untouched the subchondral bone, without correcting the rotational alignment of the trochlea. These unideal designs with few component sizes available, improper surgical technique, inadequate instrumentation and unfavourable indications provided poor outcomes. Second-generation PFAs allow a correction of trochlea rotation or dysplasia and are associated with good results at short- term and midterm follow-up [1]. Early complications like patellar maltracking, instability or catching and snapping of the patellar component during knee flexion were significantly reduced
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call