Partial (or unicompartmental) knee replacement is the surgical replacement of part of the knee joint.
Partial/unicompartmental knee replacement is a newer procedure than total knee replacement, and has been added to the armamentarium for those patients where the arthritis is restricted to one compartment
'Uni' = 'one'. 'Compartment' = a functional area of the knee.
So a unicompartmental knee replacement is one which replaces only one of the three compartments of the knee:
- the joint on the inner (medial) side ('medial compartment')
- the joint on the outer (lateral) side ('lateral compartment')
- the joint under the kneecap ('patello-femoral compartment')
Thus one can have -
Patellofemoral replacement (resurfacing)
The two parts of the prosthesis replace the articulating surface of femur and patella.