Treatment and stabilisation of kneecap instability involving the medial patellofemoral ligament (MPFL) with bone osteotomy for mal-alignment
WHAT IS KNEECAP INSTABILITY?
Knee instability occurs when the knee moves from one side to the next or twists uncontrollably. Patellar instability arises when the patella shifts from its usual place in the groove at the tip of the femur, which helps secure the kneecap in position. As a result, patellar instability feels like the knee is about to give way, which occurs when the patella shifts from the trochlear groove.
Kneecap instability presents with the following symptoms:
- Knee pain
- Swelling and stiffness over the kneecap
- A popping or cracking sensation/sound that emanates from the knee when climbing stairs or bending the affected knee
- Feels as if the kneecap is moving loosely from one side to another
What is the medial patellofemoral ligament (MPFL), and how does it contribute to kneecap instability?
The medial patellofemoral ligament (MPFL) is a static structure of the patella that helps stabilise and support the kneecap. Usually, the MPFL is affected when the patient suffers from patellar instability.
How do you address patellar instability involving the MPFL?
Surgical reconstruction of the medial patellofemoral ligament (MPFL) is the mainstream treatment for patellar instability. Typically, MPFL reconstruction is done to address recurrent kneecap dislocation causing chronic patellar instability. A tissue graft, normally the patellar tendon, is taken from the patient or a donor and used to rebuild the ligament and secure the kneecap on the femur.
How do you perform a bone osteotomy for mal-alignment?
A bone osteotomy is a surgery that entails severing bone or increasing bone tissue in order to re-mould or reposition the bone. An osteotomy is done to correct the position of a detached or deformed joint. The procedure can also be performed to manipulate the length of bones and repair damaged joints.
The procedure involves creating an incision over the skin, and thereafter, the surgeon uses guide wires to outline the amount of bone that needs to be removed. Then, Dr Vardi uses a saw to cut out the affected portion of bone, and afterwards, the space between the bone edges is closed. Sometimes, a bone graft is placed in the gap where the bone was taken. Instrumentation (pins, plates, screws & staples) are used to secure the new bone as it heals in place.