Knee Anatomy

The knee is a hinged joint that involves four bones: the thighbone or femur, the tibia, the fibula, and the patella or knee cap. The femur makes up the top of the joint, the tibia is the bottom weight-bearing bone, the patella provides protection for the bones, and the fibula provides ligament attachments for additional stability.

Four ligaments in the knee connect all the bones to each other. The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) provide stability to the knee by keeping the femur and tibia from sliding out of place. The medial collateral ligament (MCL) and lateral collateral ligament (LCL) located along the inner and outer sides of the knee prevent the femur from sliding side to side.

Tendons are important elements in the body that connect muscles to bones. The most important tendons in the knee are the quadriceps tendon, which connects the quadriceps muscle to the patella, and the patellar tendon that connects the patella to the tibia.


Instability – It’s common for someone with a knee injury to experience joint instability. Because the ligaments and tendons in your knee provide stability to the joint, experiencing instability could indicate a stretch or tear.

Popping Sound/Locking – A clicking or popping sound and the knee locking in position are all signs that there is cartilage damage. These could also be symptoms of knee arthritis.

Swelling – Swelling in the knee could be due to cartilage wear and tear, injuries to ligaments or tendons, weakened structures of the feet, or a traumatic event such as falling on the knee.

Difficulty Bending and Straightening – If you’re experiencing difficulty bending or straightening the knee, you could be dealing with arthritis or a ligament injury.

Hip and Lower Back Pain – When your knee pain is so severe that it inhibits walking, your hips and lower back can become stressed and may also be subject to damage.

If you’re suffering from any of these symptoms, be sure to visit your doctor as soon as possible. After a thorough examination and imaging tests that may include X-rays or an MRI, your doctor should be able to determine the cause of your knee pain.

Treatment Methods

Some treatment methods include manipulation or mobilization of the knee joint, soft tissue therapy, and stretching exercises to improve stability and support of the joint. Other treatment methods typically include supportive therapies such as muscle stimulation, ultrasound, cold laser therapy, or ice therapy to accelerate the healing process.

Injections are also commonly used to treat knee pain. Different types of injections can be used to treat a number of various injuries.

It’s crucial to visit your doctor as soon as possible to determine the cause of your knee pain. Click here to schedule a consultation with one of the doctors from Aligned Medical Group. This comprehensive medical clinic is dedicated to getting you back to living healthy and pain-free lifestyle.

To learn more about knee pain,  download our free eBook, The Complete Guide to Knee Pain.