In the pincer impingement, the changes are located primarily in the joint socket. It protrudes and jams the neck of the femur in a pinching-like motion (pincer comes from a French word meaning ‘to pinch’).
The image seen in Interactive 2.2 shows a typical pincer impingement case. There are already cysts on the acetabular rim, which jut forward and jam against the neck of the femur, particularly during hip bending movements. The animated graphic demonstrates well how impingement (jamming) damages the labrum and, consequently, the articular cartilage.
The neck of the femur impinges on the labrum, initially causing a tear. Over time, the cartilage is also damaged.