The knee joint is made up of three parts: the thigh bone (femur) and the large shin bone (tibia) make up the main knee joint. The kneecap (patella) joins the femur to form a third joint, called the patellofemoral joint.
The knee joint is surrounded by a joint capsule and ligaments around the joint (the medial and lateral collateral ligaments), as well as ligaments inside the joint (the anterior cruciate and posterior cruciate ligaments). These ligaments give stability and provide strength to the knee joint.
Between the femur and the tibia is a cartilage pad called the meniscus. This pad acts as a smooth surface for the joint to move on. The knee is surrounded by tendons from the hamstring (muscle on the back of the thigh) and the quadriceps (muscle on the front of the thigh), and bursa.
The knee is considered a weight-bearing joint and plays an important part in normal walking. Most knee pain is a result of overuse. Obesity can increase the chances of having knee pain.
There are many possible causes of knee pain and include the following:
Depending on the specific cause of the knee pain, symptoms will vary, but may include:
You should contact the doctor if you are unsure of the cause of the symptoms or if you do not know how to treat the symptoms. Here are some common signs to watch for:
- Swelling of the joint.
- Pain in or around the knee.
- A crunching or grinding sound when weight is placed on the knee.
- Loss of motion.
- Feeling of the knee 'giving-way' (or instability).
- A sensation of snapping in the knee when bending.
- Inability to walk comfortably on the affected side.
- Injury that causes deformity around the joint .
- Knee pain that occurs at night or while resting.
- Knee pain that persists beyond a few days.
- Locking (inability to bend) the knee.
- Swelling of the joint or the calf area.
- Signs of an infection, including fever, redness, warmth.
- Any other unusual symptoms.
The doctor will take a medical history, perform a physical examination and probably order some tests to rule in our out certain injuries. You may receive an x-ray or an MRI. Sometimes they will need to do arthroscopic surgery to look inside the knee and see what the cause of the pain is.
Depending on the exact cause of the knee pain, treatment will vary, but may include some or all of the following:
- Ice or heat.
- Physical Therapy
- NSAIDS (medication).
- Cortisone injections
How Can Physical Therapy Help
A physical therapist can help confirm the diagnosis made by the ordering provider. They will further evaluate the knee and contact the doctor as needed. Treatment may include some or all of the following:
American Academy of Orthopedic Surgeons