What is the key feature of a grade 3 ligament injury?

The key feature of a grade 3 ligament injury is complete and active instability. In this type of injury, the ligament is completely torn, which results in a loss of stability at the joint it supports. This instability means that the joint is not able to maintain its normal alignment, and it can lead to significant functional deficits. The individual may experience a sense of giving way or inability to properly control the joint, which is profound in nature compared to lower grade injuries. This characteristic helps clinicians assess the severity of the injury and determine the appropriate treatment plan, whether that involves surgical intervention or a conservative approach. Understanding this feature is crucial for effective rehabilitation and management of the injury.