There are two types of procedure associated with the treatment of patellar instability:
Soft tissue realignment
This is carried out for cases where the anatomy is normal e.g. recurrent patellar dislocation or tilting of the patella.
The simplest form of soft tissue realignment is a lateral release where the tight lateral tissues on the outer side of the knee are released surgically, thus allowing the patella to sit properly in the groove on the front of the femur (trochlea).
Lateral release is performed arthroscopically under a general anaesthetic, usually as a day case.
In some cases the medial (inner) soft tissues may not be strong enough to keep the patella in place. This is due to the medial tissues being repetitively damaged and stretched by dislocation of the patella. In this situation the medial soft tissues may also need to be reconstructed (medial reconstruction) by re-routing one of the hamstring tendons to act as a sling to stabilise the patella. This is usually a daycase procedure.
This is carried out for cases where the anatomy is abnormal due to abnormal development (Dysplasia). Soft tissue realignment is always undertaken in association with bone realignment.
In cases where stability of the patella cannot be achieved by soft tissue procedures alone, the bony attachment of the patellar tendon (the tibial tubercle) is moved surgically to a site that is more medial (towards the inner side of the knee). This is known as tibial tubercle transfer.
Tibial tubercle transfer is always accompanied by a lateral release and medial reconstruction. If the patella is too high it can also be moved further down (called distalisation) by this procedure. The tendon and block of bone is fixed using screws. These can sometimes cause problems with kneeling afterwards and may need to be removed.
Risks of Patellar Realignment
Patellar Realignment is a common operation and most people don’t experience complications. However, as with any operation, there are risks as well as benefits. Complications are rare but can include:
• stiffness of the knee
• infection of the wound
• deep infection of the joint replacement, needing further surgery
• unexpected bleeding into the knee joint
• ligament, artery or nerve damage in the area around the knee joint
• blood clots or deep vein thrombosis (DVT)
• persistent pain the in the knee
• recurrent dislocation which may require further surgery
For more information on patellar realignment please do not hesitate to get in touch with Mr Atwal through our appointments page.