Knee pain is a common complaint that affects people of all ages. Knee pain may be the result of an injury, such as a ruptured ligament or torn cartilage. Medical conditions — including arthritis, gout, and infections — also can cause knee pain.
Many types of minor knee pain respond well to self-care measures. Physical therapy and knee braces also can help relieve pain. In some cases, however, your knee may require surgical repair.
Some important structures in the knee include:
- Femur: thighbone, connects to the tibia
- Tibia: shinbone
- Fibula: small bone that runs alongside the tibia
- Patella: the kneecap
- Meniscus: small piece of cartilage
- ACL: anterior cruciate ligament
- PCL: posterior cruciate ligament
- MCL: medial collateral ligament
- LCL: lateral collateral ligament
All of these components in the knee are responsible for supporting body weight, shock absorption, leg rotation, and stability.
Common Knee Conditions
Since the knee permits us to walk, run, jump, sit, and a variety of other movements, there are several ways that the structures in the knee can become injured. Some of the most common pain conditions that affect the knee are:
ACL Tears
The anterior cruciate ligament, or the ACL, is a strong band of fibrous tissues that extends from the front surface of the tibia to the back surface of the femur. The ACL helps to control knee movement by limiting excessive forward and backward motion of the tibia. Tears of the ACL are relatively common in athletes who play sports that involve turning, cutting, and pivoting motions. These tears can be very severe and usually require a type of reconstruction surgery. The three types of reconstructions include:
- Autograft
- Allograft
- Synthetic Graft
Meniscus Tears
The meniscus is a small piece of cartilage found twice in both knees that helps stabilize the knee during movement and acts as a shock absorber. The meniscus can be damaged or torn by minor trauma, such as twisting when you bend your knee too quickly. Most meniscus tears are common among athletes who play sports with turning or pivoting motions, as well as adults whose tendons have weakened over time. A meniscus tear will lead to pain and instability in the joint and needs either surgical or non-surgical treatment to heal.
Quadriceps Tendon Rupture
The quadriceps tendon is a strong band of tissue that attaches the four quadriceps muscles to the top of the patella. A quadriceps tendon tear is rare and can tear partially or completely. Partial tears will make it difficult to walk or participate in other daily activities and can often be repaired with physical therapy and rest. A complete tear is when the tendon is no longer anchored to the kneecap, which can be debilitating and will almost always require surgical intervention. Quadriceps tendon rupture may occur from injury or tendon weakness.
Loose Bodies
Loose bodies in the knee are fragments of bone or cartilage that break off and move around freely in the joint fluid. These fragments usually occur following trauma to the knee or due to inflammatory conditions of the knee. Loose bodies can sometimes cause damage to the articular cartilage and contribute to the development of osteoarthritis. Surgical options such as an arthroscopy or an open arthrotomy are usually the only ways to remove the loose bodies from the joint.
Treatment Options for Knee Conditions
There are a plethora of treatment options to manage and heal a variety of knee conditions. Your orthopedic specialist at Performance Sports Medicine Institute will likely recommend non-surgical treatment initially for more mild conditions. Some conservative treatment methods include:
- Physical therapy
- RICE: Rest, Ice, Compression, and Elevation
- Corticosteroid injections
- Over-the-counter pain relievers
- Knee immobilization: use of a splint or brace
- Use of crutches to limit weight-bearing
More serious knee conditions, such as ones that involve torn ligaments, joint instability, dislocation, significant swelling, fractures, or a limited range of motion, will likely require surgery. Fortunately, most knee surgeries can now be completed using an arthroscopy, which is a minimally-invasive procedure that uses small incisions and fiber-optic technology.