The back of my knee hurts after I hit it on the dashboard. What could be injured?

How the PCL is injured

The PCL stops the shin bone from sliding backwards under the thigh bone. A blow to the front of the upper shin while the knee is bent, in a road accident, a fall onto the knee on a hard surface or a tackle in football, pushes the shin back and can stretch or tear it. Unlike an ACL tear, there may be no loud pop and the swelling can be modest.

Typical symptoms are an ache at the back of the knee, pain when kneeling, discomfort going down stairs or slopes, and a vague feeling that the knee is not quite right. Higher-energy accidents can injure several ligaments, the posterolateral corner, the meniscus or the bone together.

Seek emergency care if

• The knee looks deformed, or the injury was a dislocation that went back into place
• The foot is cold, pale or numb, or you cannot move your ankle or toes
• You cannot bear any weight, or there is severe swelling within hours
• The calf swells and is very tight and painful

First steps

After a road traffic accident, the emergency team should assess you as a whole first. For the knee, use rest, ice, compression and elevation, and crutches if walking is painful. Avoid kneeling and do not return to sport until the knee has been examined. Keep the swelling down and work gently on movement as pain allows.

Assessment and treatment in Doha

Dr. Gelber examines the knee for backward sag of the shin and tests every ligament, because combined injuries change the treatment plan. An MRI shows the PCL and other structures. Many isolated PCL tears are treated without surgery using a brace and a quadriceps-focused rehabilitation programme. Reconstruction is considered for combined injuries or when the knee remains unstable despite rehabilitation.