How is a PCL Injury diagnosed?
Dr. Vidal will perform a detailed clinical exam, medical history and background, including events leading up to the injury. X-rays and an MRI scan will determine the extent of the injury as well as other injuries inside the knee joint. In cases where the PCL injury is isolated, without further knee injuries, it can often heal over time without surgery. It is vital for patients in Vail, Aspen and the surrounding Denver, Colorado communities to receive a correct evaluation and diagnosis. This particular ligament tear needs to heal in a stable position, rather than in an elongated and nonfunctional position. Dr. Armando Vidal understands the intricacies of PCL injuries and how to treat them properly – both surgically and non-surgically. Some of tests he may use to test the PCL injury and the instability of the knee the injury has caused are:
- Posterior Drawer test: A specific maneuver used to test stability. With the patient lying down, Dr. Vidal will bend the knee while applying slight pressure and rotation. Some rotation is normal, and he will compare the degree of shift with the healthy knee.
- Dial Test: Tests knee stability. Dr. Vidal turns the foot outward. Excessive rotation can indicate a PCL injury.
- Assessment for a Varus Thrust Gait: In short, Dr. Vidal looks for a crooked knee, or for the knee to bow outward during adduction. (Adduction is the movement made when walking forward in a straight line).
- Quadriceps Active Test: Done with the knee bent, the patient pushes their lower leg forward using their quadriceps muscle while Dr. Vidal pushes against the movement at the ankle. The knee should not move forward noticeably through the movement.
Imaging is also very useful in diagnosing these injuries. Similar to posterolateral corner injuries, imaging can be tricky in PCL injuries. In acute injuries, an MRI can be reliable in indicating that an injury occurred, but in and of itself does not tell you the severity of the injury or if it is competent. In chronic injuries or in the setting of revision surgery – an MRI is not an accurate measure of how competent the PCL really is. In fact, in the chronic setting, the PCL can look totally normal on MRI. In these cases, a radiographic stress test will be performed. This essentially means that we will stress your knee (and your normal knee as a comparison) similar to what was done on physical examination and obtain an X-ray while performing the stress. Any asymmetry will be measured to determine functional integrity of the PCL. This is a key test and is the only objective measure of PCL integrity.