Other surgical techniques offered
When the bones do not align properly, joint forces are not evenly distributed and may overload on one side, causing wear and tear, pain and possibly degeneration. With an osteotomy (a cut in the bone) the joint replacement surgeon cuts and realigns the bones (both for tibiofemoral and patellofemoral malalignment). In recovery, the bones are in a new position and force (weight) is shifted from the overloaded or damaged side to the normal side of the joint.
While these surgeries have been performed since the 1950s, in recent years many more patients have received joint replacement surgery. Nevertheless, they remain an important part of a knee preservation practice. At times, the new alignment can resolve joint pain. However, when the goal is optimizing joint preservation, the realignment unloads the involved side of the joint to optimize the environment for meniscal transplantation and/or articular cartilage restoration.
There can be many reasons for knee pain in the patella, but in some patients the kneecap does not track in the middle of the femoral groove. Repositioning the kneecap is accomplished by moving the tibial tubercle attachment of the patellar tendon and redirecting the forces acting on the kneecap. This may be combined with MPFL reconstruction as well as patellofemoral cartilage restoration.
Alternative types of surgery to osteotomy are under investigation. Dr. Farr is a design surgeon involved in the development of an internal “shock absorber” for the knee (Calypso®, by Moximed) to unload the inner (medial aspect) part of the knee. The clinical trial is now fully enrolled and outcomes will be reported in 2022.
For the patellofemoral compartment, Dr. Farr is a consultant for a company that has developed a small implant to redirect patellofemoral forces without cutting the tibial. The first clinical trials will begin in 2020. Please visit centerwatch.com, clinicaltrials.gov or ask Dr. Farr for new details.