TORN CRUCIATE LIGAMENT

The cruciate ligaments are the central stabilisers of the knee, and are situated right in the centre of the knee, connecting the femur to the tibia.

Tears of one or both of the cruciate ligaments in a knee - the anterior cruciate ligament and the posterior cruciate ligament - usually leads to knee laxity and feelings of knee instability. Continuing instability may cause secondary damage to the joint cartilage surface of the bones or to the menisci.

The anatomy of the cruciate ligaments is complex and hard to reproduce during cruciate ligament reconstruction surgery. The relationship of the cruciates to the other ligament structures of the knee is important in understand the complexity of complex instability, such as that involving the posterolateral corner.

Continued instability after cruciate reconstruction is often due to failure of the surgeon to recognise damage to the structures of the posterolateral corner and to reconstruct the anatomy.

Understanding of the major role played by rehabilitation has altered the outcome of cruciate ligament reconstruction surgery. After cruciate surgery the therapist needs to carefully balance the regaining of movement with the early protection of the ligament reconstruction.

Although the complication of a stiff knee may occur after any knee surgery, it is relatively more common after cruciate ligament surgery. This is largely an avoidable complication, but needs to be recognised early and managed competently for one to expect a full resolution. Cruciate grafts may fail for a variety of reasons, but in many cases the cause of failure turns out to have been avoidable. We are still learning why cruciate grafts may fail and how to avoid this complication.