Washington Redskins fans can breathe a sigh of relief. Despite a gruesome injury, RGIII suffered only a grade 1 sprain of his lateral collateral ligament. Now attention turns to when the rookie phenom will return to action.

The lateral collateral ligament is one of the four main stabilizing ligaments of the knee, along with the anterior cruciate ligament, posterior cruciate ligament, and medial collateral ligament. It is a small ligament on the lateral side of the knee (the side away from the midline of the body).

LCL sprain
An image from an MRI of a patient with a multi-ligament knee injury showing a sprain of the LCL (yellow arrow)

LCL tears are unusual as isolated injuries. Frequently the LCL and the other supporting ligaments on the outside and back of the knee (the posterolateral corner) are torn in multi-ligament knee injuries. Combined with ACL or PCL injuries, lateral collateral ligament injuries would require surgical treatment.

An isolated lateral collateral ligament injury, especially one found to be a grade 1 sprain, does not require surgery. Often a knee brace provides side-to-side stability while the ligament heals.

Return to sports usually occurs quickly, often within a few weeks. Since the LCL helps to provide lateral and rotational stability, cutting and changing directions quickly can be difficult soon after the injury.

In this interview with Dimitri Sotis on WTOP All News Radio on December 10, 2012, Dr. Geier discusses the injury and treatment of Robert Griffin III, the message that his injury sends to youth athletes, and the rise of concussions in football.

Griffin was hurt by a tackle from Baltimore Ravens defender Haloti Ngata. The hit caused what looked like a hyperextension injury when viewed in slow motion on television replay. Since RGIII had an ACL injury on that same knee in 2009, fans feared hearing that he could have suffered a similar injury again. Fortunately his outlook appears to be much better.

Initially team doctors and athletic trainers will rehab Griffin’s knee aggressively. They will work to restore motion and strength and to decrease pain and swelling. They will put him through functional drills that replicate his actions on the field. When he can demonstrate that he can do everything he needs to do as a quarterback, they will clear him to play.

I expect that while the ligament sprain itself should heal quickly, the team might be conservative with their star. If there’s any question about his knee or ability to run, I wouldn’t be surprised if Redskins’ doctors and coaches hold out RG3 until he returns to 100%.

Note: This post appears in a modified form as an article I wrote for Bleacher Report.