Jock Doc

Not all sprained knee ligaments are equal

Q. I was skiing last month and hurt my left knee. On the same trip, my friend also hurt her left knee. She was told that she had a sprained ligament in her knee and she was given a brace and already feels normal. I was also told that I had a sprained ligament and was given a brace but since the brace is removed my knee hurts and feels like it will give way. I went to a doctor who said I had an ACL tear and would need surgery. If the diagnosis was the same, how come my friend is better with just a brace and I need surgery?

A. Although you and your friend were both told that you had a sprained ligament, the injury may not have been as severe with your friend’s sprain. You may not have even injured the same ligament. The medial collateral ligament “MCL” and the lateral collateral ligament “LCL” are on the inside and outside part of the knee, respectively. These control side to side motion. If either of these is injured it has a good blood supply and usually will heal without surgery. Sprains can be on a microscopic level, grade-I; partial tears of the ligaments, grade-II; or complete tears of the ligament, grade-III. Even grade-III tears of the MCL and LCL will usually get better with a period of bracing followed by physical therapy. They usually do not need surgery.

However, two other ligaments in the knee, the ACL “anterior cruciate ligament” and PCL “posterior cruciate ligament” cross in the knee and are important for pivoting activities. These ligaments do not have a good blood supply and when injured will not heal themselves. ACL sprains, particularly grade-III injuries, may result in significant instability as well as associated cartilage damage in the knee.

Your doctor may initially prescribe a physical therapy program to rehabilitate the knee and then may require surgical intervention to make a new anterior cruciate ligament. An MRI scan may help confirm the diagnosis and determine if there are other associated injuries in the knee joint. If you are unsure as to what your doctor says, I recommend you discuss this further with your orthopedic surgeon or perhaps get a second opinion.

Dr. Harlan Selesnick is team physician of the Miami Heat and director of Miami Sports Medicine Fellowship, Doctors Hospital. Send your questions to