By: Dr. Clifford Yun, PT,DPT
Knee pain is a general diagnosis of discomfort to the knee joint. Before diving into the types of knee pain we should describe the knee joint itself. After understanding the anatomy of the knee we can better understand how and why we get pain there.
The knee is made up of four boney parts. Patella is the kneecap. The tibia is the large bone of the bone below the knee. The femur is the largest and longest bone in our body that goes from the hip to the knee joint The fibula is the smaller of the two bones of the lower part of the leg, it runs along the outside of the leg. (image below is from the American Academy of Orthopedic Surgeons)
Cartilage is the rubbery cushion inside of the knee that acts as a shock absorber when we run, jump, walk and more on our feet. The ligaments and the muscles work to stabilize and bend (flexion) or straighten (extension) the knee.
Common complaints of pain to the knee are related to the sides of the knee or inside of the knee. The lateral (outside) and medial (inside) of the knee are protected by the lateral collateral and medial collateral ligaments. Motions that cause direct pressure to the sides of the knee can cause tearing of the ligaments. The anterior and posterior cruciate ligaments are fight forces against the knee that pull the femur and tibia behind the knee or in front of the knee.
Weaknesses in the knee can increase the risk of injury to the ligament structures. Pivoting, torsion, types of forces create possible injury to all four of the ligaments in the knee. Injury to the anterior cruciate ligament (ACL) can also be correlated with a tear of the rubbery meniscus and the medial meniscus. This type of injury is commonly referred to as the "Unhappy Triad".
Other types of knee pain are found around the patella. The pain can be around the top of the knee, bottom of the knee, or behind the knee. The above the knee pain can come from the quadriceps muscle. This a group of four long muscles that attach from the hip to patella. When there is a strain to these muscles or a weakness of one of the muscles over the others, we can have a general imbalance of forces pulling the patella. This imbalance can contribute to poor tracking of the patella up and down the groove of the femur. We see this often with those who have a knee alignment that pulls the knee inwards (knock knee) which is knowns as genu valgus. When the knees pull too much outwards it is defined as genu varus. These angles and weaknesses can lead to the break down of cartilage between the joints of the knee and create arthritis between the femur and tibia as well as under the patella as it glides over the femur. For more information on arthritis go here (Arthritis and Pain). Prior to the onset of arthritis between the femur and tibia, we will likely find swelling and pain related to the meniscus.
To the left is an image of the right knee joint with a torn meniscus. (image is from https://phoenixshoulderandknee.com) Swelling from this tear can cause fluid build up at the front and lateral side of the knee. Pain is usually described as an ache to the lateral side of the knee with more pain occurring while going down stairs rather than up stairs; although pain can occur going up stairs
Knee pain overall is a large topic for discussion but understanding the anatomy of the knee should help you understand why you can receive very specific exercises to return you to your pre-injury status. Beyond strengthening, heating or icing, a physical therapist should utilize more tools to improve healing. At Alta PT we work with manual therapy skills, filming equipment, and the latest in healing technology to reduce your swelling and pain and get you to functional movements related to your work, sport and daily activities.
Before you self diagnose your particular knee injury contact us at Alta PT or your recommended physical therapist. Remember that with Direct Access in all 50 states you do not have to see a medical doctor before treatment and evaluation from a physical therapist. To learn more how to #GetPT1st with Direct Access Click Here.