Understand exactly what an unhappy triad injury is
The unhappy triad, also sometimes known as the terrible triad, O’Donaghue’s triad, or a blown knee, is a serious knee injury in which the anterior cruciate ligament(ACL), medial collateral ligament(MCL), and the meniscus are all partially or fully torn. This happens to about 25% of serious athletes when they have knee injuries and can take surgery and substantial recovery time to heal since the damage is spread throughout the entire knee. A unhappy triad is most common in contact sports and extreme sports like motocross and always requires surgery for full recovery. The most common cause for an unhappy triad is when the foot is planted and bearing weight and then it is forced and pushed in another direction. Imagine a quarterback about to throw a pass who gets hit in the knee. This type of impact causes the unhappy or terrible triad.
Unhappy Triad: Torn ACL Injury
The most serious of the unhappy triad injuries is the partial or fully torn ACL or anterior cruciate ligament. This part of the unhappy triad is considered the most serious because the ACL provides stability to the entire knee and it is can very difficult to walk or move with a torn ACL. Additionally since the ACL connects the femur and tibia and controls movement in your knee, tearing your ACL makes normal knee function nearly impossible. Most torn ACLs require surgery and can take 6-9 months to recover in some cases, specifically when full reconstruction is needed.
Unhappy Triad: Torn Meniscus Injury
The second most problematic injury of the unhappy triad is the torn meniscus. The tear happens to the lateral meniscus in about 80% of the cases and the medial meniscus tear happens in about 20% of cases. The meniscus basically plays the role of the “shocks” in the knee and helps the knee to distribute weight and pressure. A torn meniscus usually needs to be repaired surgically since it does not heal well on its on.
Unhappy Triad: Torn MCL Injury
The final injury that occurs as part of an unhappy triad is either a complete or partial tear to the MCL or medial collateral ligament. The MCL provides stability on the outside of the knee joint and runs along the inside of the knee. A partial or complete MCL tear normally does not require surgery and therefore is the least problematic with an unhappy triad. That said, an MCL does take time to heal and can still cause pain and discomfort. Some doctors may decide to repair the MCL during the treatment of an unhappy triad since surgery is already being performed.