Which history finding is typical for a PCL injury?

Which history finding is typical for a PCL injury?

• A. Traumatic injury causing posterior translation of the tibia on the femur
• B. Feeling of instability with weightbearing and change of direction
• C. Immediate effusion within hours
• D. Localized posterior knee pain with kneeling or decelerating

Answer: (C)

Initial knee swelling within hours after a trauma points to an intra-articular bleed from a ligament tear. When the PCL is injured, blood can fill the joint, producing a rapid effusion that you notice soon after the injury. This rapid swelling is a classic historical clue for a cruciate ligament tear, including the PCL. Instability with weightbearing and change of direction is more characteristic of ACL injuries, not the typical early history of a PCL tear. Localized posterior knee pain with kneeling or decelerating can occur, but it’s less specific than the quick effusion. Posterior translation of the tibia on the femur is an exam finding (not a history), revealed on tests like the posterior drawer.

Initial knee swelling within hours after a trauma points to an intra-articular bleed from a ligament tear. When the PCL is injured, blood can fill the joint, producing a rapid effusion that you notice soon after the injury. This rapid swelling is a classic historical clue for a cruciate ligament tear, including the PCL.

Instability with weightbearing and change of direction is more characteristic of ACL injuries, not the typical early history of a PCL tear. Localized posterior knee pain with kneeling or decelerating can occur, but it’s less specific than the quick effusion. Posterior translation of the tibia on the femur is an exam finding (not a history), revealed on tests like the posterior drawer.