Houston Methodist. Leading Medicine.
Houston Methodist. Leading Medicine

Houston Methodist Orthopedics & Sports Medicine

Common Injuries - Knee

Anterior Cruciate Ligament (ACL) Tears

The ACL is a ligament deep in the knee which keeps the leg bone (tibia) from slipping forward with respect to the thigh bone (femur). The typical history of a tear involves a sudden giving way followed by a painful “pop” and swelling. It is a common injury in twisting and pivoting sports such as skiing, soccer and basketball. While ACL tears are more common in women, they occur frequently in men as well. The pain usually subsides with physical therapy and bracing, but surgical reconstruction is usually recommended for those who desire a full return to cutting and pivoting activities such as sports. Arthroscopic ACL reconstruction is the most common ligament surgery in the knee.

Medial Collateral Ligament (MCL) Tear

This is the most common knee ligament injury. The MCL is the ligament which runs along the inner side of the knee from the thigh bone (femur) down to the leg bone (tibia).  It may be injured from a twisting injury or from a blow to the outside of the knee, as often occurs in football. Fortunately, the vast majority of MCL tears can be treated successfully with bracing and physical therapy.

Posterior Cruciate Ligament (PCL) Tears

The PCL is a ligament deep in the knee which crosses the ACL on its way to the back of the knee. It keeps the leg (tibia) from slipping backwards with respect to the thigh bone (femur). It can be injured from a fall on a bent knee. It is often treated with physical therapy and bracing. It is less common than an ACL tear, but the two may occur together in certain knee injuries. Surgical reconstruction may be needed to help stabilize the knee.

Cartilage Injuries

Articular (joint surface) cartilage is the thin protective layer of cartilage that covers the ends of the bones inside a joint.  It provides the friction-free smooth gliding surface that allows joints to move normally. Traumatic injuries such as a fall, or striking the knee against the dashboard can damage or shear off an area of this cartilage. When torn or damaged cartilage is left untreated, it can progress to arthritis.  When these injuries cause pain, swelling and catching in the knee, treatment may be indicated. This is a rapidly-growing area of orthopedics now that surgeons are able to re-grow or transplant cartilage back into the knee to delay or prevent the progression to arthritis.

Kneecap Pain (Patellar Chondromalacia)

Young active patients often complain of pain on the front of both knees that is worse with running or using stairs. This may be due to overload of the articular cartilage on the back side of the kneecap. It improves with rest and does not cause the knee to swell. The majority of cases can be treated with a quadriceps muscle strengthening program under the direction of a physical therapist. Occasionally NSAIDs or even injections can be helpful. Surgery is rarely needed.

Kneecap (Patella) Dislocation

The kneecap can slip out of place either as a result of a direct blow or from a non-contact twisting injury. It causes pain and swelling, and may lead to persistent episodes of instability. Initial treatments include physical therapy and bracing. For patient with recurrent dislocation or secondary damage such as a loose piece of bone and cartilage floating in the knee, surgical stabilization is recommended.

Meniscal Tears

The menisci are thick rubbery cartilages which sit between the bones in the knee. There are two; one on the inner (medial) and one on the outer (lateral) side of the knee. They function as shock-absorbers and stabilizers which help to protect the articular cartilage on the end of the bones. They may be injured from an acute injury or from wear-and-tear.  Patients experience mild swelling and intermittent pain along the affected side of the knee which is worse with twisting or squatting. The tears generally do not heal without treatment and can become larger and cause the knee to lock up. Outpatient knee arthroscopy is recommended to either remove the torn flap of meniscus or to suture (sew) the meniscus back into position.

IT Tendonitis (Runner’s Knee)

The soft tissue which runs from the pelvis (Iliac) to the leg (tibia) is known as the IT Band. It crosses the outside of the hip where it can contribute to bursitis and then travels along the outside of the knee. The repetitive rubbing over the side of the knee, such as occurs with distance running, can result in inflammation. It generally causes lateral knee pain, without swelling or catching sensations.  This is treated with physical therapy, NSAIDs and activity modification.

Patellar Tendonitis (Jumper’s Knee)

The patellar tendon runs from the bottom of the kneecap (patella) down to the front of the leg bone (tibia). Repetitive activities such as jumping can lead to inflammation of the tendon- tendonitis. This is generally treated with physical therapy, NSAIDs, and a special strap brace. Younger patients may develop similar symptoms from inflammation of the growth plate at the site of patellar tendon attachment to the leg, which is known as Osgood-Schlatter disease.

Tendon Ruptures (Patellar / Quadriceps)

There are two major tendons which cross the front of the knee and allow us to extend the leg. The quadriceps tendon attaches the thigh muscles to the kneecap. The patellar tendon then attaches the kneecap down to the leg bone (tibia). Tears of either tendon can occur from falls or sporting activities, such as attempting to jump for a rebound. These require urgent surgical treatment to restore the ability to walk and use the knee normally.