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The most common types of ligament injuries include:

ACL & PCL Ligaments

The knee can be divided into three compartments: patellofemoral, medial, and lateral compartment. The patellofemoral compartment is the compartment in the front of the knee between the kneecap and thighbone (femur). The medial compartment is the area on the inside portion of the knee, and the lateral compartment is the area on the outside portion of the knee joint.

The patella is a small piece of bone in front of the knee that slides up and down the groove in the femur bone during bending and stretching movements. The ligaments on the inner and outer sides of the patella hold it in the femoral groove and avoid dislocation of the patella from the groove.

Patellofemoral stabilization is surgery for stabilization or prevention of dislocation of the patella for the treatment of patellofemoral instability.

Patellofemoral instability means that the kneecap (patella) dislocates or moves out of its normal pattern of alignment. This malalignment can damage the underlying muscles and ligaments that hold the knee in place. Patellofemoral instability causes pain when standing up from a sitting position and a feeling that the knee may buckle. When the kneecap slips partially or completely severe pain, swelling, bruising, deformity, and loss of function of the knee can result. Additionally, because of pressure on nerves and blood vessels, the patient may experience numbness below the dislocation.


A combination of factors can cause this abnormal tracking and include the following:

  • Weak anterior thigh muscles lead to abnormal tracking of the patella.
  • Patellofemoral arthritis: Patellofemoral arthritis occurs when there is a loss of the articular cartilage on the back of the kneecap. This can eventually lead to abnormal tracking of the patella.
  • Flat feet or fallen arches can cause misalignment of the knee joint.
  • A high angle between the hips and knees (Q angle) may result in knock knees due to maltracking of the patella.

To diagnose Patellofemoral instability, the doctor will

  • perform a thorough medical examination including medical, medication and social history.
  • blood work, imaging and x-ray may be performed to determine the extent of injury.


The aim of the surgery is to realign the kneecap in the groove and to decrease the Q angle.

Patellar realignment surgery is broadly classified as follows:

  • Proximal re-alignment procedures: ligaments on the inside of the patella may be shortened. Structures that limit the movements on the outside of the patella may be lengthened.
  • Distal re-alignment procedures: the Q angle is decreased by moving the tibial tubercle towards the inner side of the knee.

The surgery is performed under sterile conditions in the operating room under spinal or general anesthesia. A larger incision is made over the front of the knee. After visualizing the type and severity of the injury, the surgeon decides on the appropriate surgery.

A lateral retinacular release may be performed, where tight ligaments on the lateral side (outside) of the patella are released or cut enabling the kneecap (patella) it to slide more easily in the femoral groove. The surgeon may also perform a procedure to realign the quadriceps by tightening the tendons on the inside or medial side of the knee.

Tibial tubercle transfer (TTT) may be performed if the misalignment is severe. This procedure involves the removal of a section of bone where the patellar tendon attaches to the tibia. The bony section is then shifted and properly realigned with the patella and reattached to the tibia with two screws.

Medial patellofemoral ligament (MPFL) reconstruction with graft is another surgery employed for severe patellofemoral instability. This procedure involves attaching a new ligament from the medial aspect of the thighbone into the medial aspect of the kneecap, enhancing the medial pull on the kneecap guiding the kneecap successfully into the trochlear groove. When the malalignment is repaired and confirmed, the incisions are closed with sutures and sterile dressings applied.


  • Pain, swelling, and discomfort in the knee area may be present initially.
  • The leg should be elevated while resting to prevent swelling and pain.
  • Pain and anti-inflammatory medications may prescribed as needed.
  • Antibiotics may be prescribed to address the risk of infection.
  • The surgical site should be kept clean and dry.
  • Crutches will be provided for the first few weeks following the surgery.
  • Instructions on restricted weight-bearing will be given.
  • The patient should walk with assistance as frequently as possible to prevent blood clots.
  • Refrain from strenuous activities and lifting heavy weights for the first couple of months.
  • Gradual increase in activities is recommended.
  • The patient is usually able to resume your normal activities in a few months
  • Return to sports may take 6 months or longer.
  • An individualized physical therapy program is designed to help strengthen the knee muscles and optimize knee function.
  • Follow-up appointment will be scheduled to monitor progress.

Total Knee Replacement

A knee replacement is a surgical procedure in which the diseased portions of the bones within the knee are replaced with a prosthesis. Knee replacements are typically a solution to pain from the three types of arthritis: osteoarthritis, rheumatoid arthritis, or post-traumatic arthritis. Rheumatoid arthritis is the result of inflammation in the knee joint and is the most common of the three types of arthritis. Osteoarthritis occurs with age and wear and tear on the joint as the cartilage protecting the bones begins to wear away causing the bones to rub against one another. Ligaments on the inside of the patella are shortened. It usually occurs in people over 50 years of age.

Post traumatic arthritis is often the result of a serious knee injury which fractures the bones and causes damage to the ligaments and cartilage.

To measure the severity of arthritis, four grades classify the extent of injury

  • Grade 1—Early changes show fissuring in the cartilage (Breaks)
  • Grade 2—More extensive thicker breaks in the cartilage
  • Grade 3—intermittent loss of cartilage with breaks
  • Grade 4—Exposed subchondral bone (below the cartilage)


The physician may advise total knee replacement for:

  • Severe knee pain that limits daily activities (such as walking, getting up from a chair or climbing stairs)
  • Moderate-to-severe pain that occurs during rest
  • Chronic knee inflammation and swelling that is not relieved with rest or medications
  • A bow-legged knee deformity
  • Failure to obtain pain relief from medications, injections, physical therapy, or other conservative treatments


The goal of total knee replacement surgery is to relieve pain and restore the alignment and function of your knee.

  • The surgery is performed under spinal or general anesthesia.
  • An incision is made in the skin to expose the knee joint.
  • The damaged portions of the femur bone are cut at appropriate angles.
  • The femoral component is attached to the end of the femur.
  • The surgeon then cuts or shaves the damaged area of the tibia (shinbone) and the cartilage. This removes the deformed part of the bone and any bony growths, as well as creates a smooth surface on which the implants can be attached.
  • The tibial component is secured to the end of the bone with bone cement or screws.
  • The surgeon then places a plastic piece called an articular surface between the implants to provide a smooth gliding surface for knee movement. This plastic insert will support the body’s weight and allow the femur to move over the tibia like the original meniscus cartilage.
  • The femur and the tibia with the new components are then put together to form the new knee joint.
  • The knee rear surface is also prepared to receive a plastic piece.
  • When all the new components are in place, the knee joint is tested for range of motion.
  • The entire joint is then irrigated and cleaned with a sterile solution.
  • The incision is closed; drains are inserted, and a sterile dressing is placed over the incision.

Post operative Care

Rehabilitation begins immediately following the surgery.

  • Knee immobilizers are used to stabilize the knee.
  • A physical therapist will teach specific exercises to strengthen and restore knee movement.
  • The physical therapist will also determine a home exercise program for leg muscle strength.
  • Crutches or a walker will be prescribed.
  • A continuous passive motion (CPM) machine can be used to move the knee joint. Continuous passive motion is a device attached to the treated leg that constantly moves the joint through a controlled range of motion.
  • Athletic Orthopedics

    Athletic Orthopedics

    Athletic Orthopedics

    Athletic Orthopedics
    & Knee Center
    9180 Katy Freeway
    Suite 200
    Houston, TX 77055





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