Posterior cruciate ligament tear

The posterior cruciate ligament is considered the strongest intra-articular ligament of the knee and acts as the primary restraint to backward movement of the tibia relative to the femur. It also contributes to rotational stability, especially when the knee is flexed. When a posterior cruciate ligament tear occurs, the tibia may rest slightly further back than normal and, in more advanced injuries, this can be seen clinically as a posterior sag when the knee is bent. In the acute phase, there is usually pain, swelling, stiffness and difficulty with tasks such as walking downhill, descending stairs or fully loading the injured leg. In the chronic stage, symptoms may be more subtle, with vague discomfort, fatigue around the knee and a sense that the joint is not completely secure during demanding movements.

Diagnosis relies on a combination of the injury history and targeted clinical tests, including posterior drawer testing and observation for posterior sag of the tibia. Magnetic resonance imaging is often used to confirm the presence and extent of the posterior cruciate ligament tear and to identify any associated injuries affecting the menisci, cartilage or other ligaments. This broader picture guides the overall treatment plan. Many isolated posterior cruciate ligament tears can be treated non-operatively with a structured rehabilitation programme, whereas more severe or multi-ligament injuries may be candidates for posterior cruciate ligament reconstruction after careful discussion of the potential benefits, risks and functional goals.

In the case of a posterior cruciate ligament tear, physiotherapy is a key part of treatment, whether the approach is conservative or involves posterior cruciate ligament reconstruction. In the early stages, the goals are to control pain and swelling, protect the knee from excessive backward movement of the tibia and maintain as much comfortable range of motion as possible within safe limits. A brace may be used to hold the knee in extension or in a controlled flexion range and deep loaded knee flexion or exercises that pull the tibia backwards are typically limited.

As symptoms settle, rehabilitation focuses on gradually strengthening the quadriceps to provide better anterior support for the tibia, strengthening the gluteal muscles and improving balance and neuromuscular control, especially in single-leg positions. Exercises are progressed in a stepwise way so that the demands increase, but the stress on the posterior cruciate ligament remains appropriate for the healing stage. After posterior cruciate ligament reconstruction, rehabilitation protocols usually combine time-based phases with clear progression criteria: early protection of the graft and controlled motion, followed by strengthening and functional retraining and, in the later stages, a graded return to running, direction changes and sport-specific activities where this is an aim.