If you’re experiencing knee pain from squatting motions, sitting, or knee flexion, there is a possibility that your knee’s ligaments, tendons, or cartilage have been damaged or degraded.

To put scientific jargon into layman’s terms, if you’re experiencing front, back, inner, or outer knee pains, here is a break-down of what it could be.

Common Knee Pain Diagnoses

The anatomy of the knee is complex and interconnected in many ways.

Whether the pain resides with the back, front, or medial/ lateral (side) parts of the knee, the damage may originate from any part of the knee’s anatomy.

It is difficult to decipher where the pain may be coming from, which is why diagnosing the specific area of pain can help you understand which part of your knee has been affected.

Here are a few common questions you can ask yourself when experiencing knee pain when sitting or squatting.

1. Is the pain coming from the front, sides, or back of my knee?
2. Is my knee pain coming from standing, sitting, flexing, all of the above? Not sure?
3. How active am I?
4. Have I started new activities? 
5. Am I wearing different footwear than normal? 

Answering these questions can help you pinpoint the possible cause of your pain and help give your doctor a better idea of where your knee pain is coming from.

With this knowledge in mind, there are four common diagnoses that are associated with acute knee pain.

1. Jumper’s Knee (Patellar Tendonitis)

Jumper’s Knee is usually a result of the overuse of the Patellar tendon (refer to the picture above).

Oftentimes jumper’s knee is symptomatic of overload and overuse of your quadriceps (quad) muscle group.

The quad muscles are involved in a variety of movements which include jumping, kicking, squatting, running, or any generally explosive movement involving the legs.

Energy and the pressure of impact are often distributed among the Quad muscle. After extended use, however, the pressure begins to cause inflammation in the tendon.

Repeated use especially after sustaining the injury can lead to tears.

Inflammation is usually a result of microscopic tears in the tendon.

This triggers a healing response from your body, flooding the damaged area with blood, nutrients, antioxidants, and other fluids that are designed to help the healing process.

For the old, but young at heart, the cause of Jumper’s Knee is usually due to repetitive microdamage and degradation.

While resting the knee seems like the best method of healing, small and steady movements and use of your affected knee is also a vital part of the recovery process.

Here are a few symptoms to determine if you have Jumper’s Knee.

1. Tenderness and pain originating from the front of your knee (beneath your knee knee cap)
2. Pain with sudden movements
3. Pain with extending your knee

2. Runner’s Knee

Runner’s Knee is usually the result of irritating the lining and soft tissues in the knee. It is known as Runner’s Knee because the repetitive movements of running can easily cause pain and inflammation. These repeated movements are usually felt with knee pain when squatting.

Runner’s knee is a common term used to describe a group of conditions that create pain behind and around the patella or kneecap.

The conditions can include anterior knee pain syndrome, patellofemoral malalignment, chondromalacia patella, and iliotibial band syndrome.

For patients with runner’s knee the pain is often most acute when the knee sits in a flexed position. While there are many different diagnoses for Runner’s Knee, it is usually a series of linings and soft tissues that have become irritated due to consistent pressure.

Runner’s Knee is usually more common in women, particularly middle-aged women. Weight can also be a contributing factor to the development of Runner’s Knee along with failure to stretch/ warm-up.

As the name of the condition suggests, Runner’s Knee is a common injury in people who enjoy recreational or professional running.

However, this is a problem that is not exclusive to runners. As previously mentioned, there are a number of reasons that one may develop Runner’s Knee including biking, hiking, and impact sports.

Here are a few indicators that you may have Runner’s Knee.

1. Pain coming from the sides of your knee
2. A grinding originating from your knee after a period rest
3. Popping and pain from knee loading (walking up stairs or squatting)
4. Pain or snapping along the outside of the knee

3. Baker’s Cyst (Popliteal Cyst)

The popliteal area refers to the area behind the knee. Most symptoms of a Baker’s Cyst include general stiffness, a mass in the back of the knee, and pain in the back of the knee.

The injury is a result of cartilage or soft tissue damage which, in turn, causes a build-up of what is known as synovial fluid (a lubricant that greases the joint for movement).

After continued movement, the body produces a large amount to help cushion the knee, but the fluid pushes out the back of the knee and a cyst begins to form behind the knee.

Unlike some other knee pains, a Baker’s Cyst might go undetected. Some common ways to diagnose the pain is if you experience any of the following symptoms.

1. Feel and/or see a lump behind the knee
2. Pain when completely flexing your leg or inability to flex entirely.

4. Iliotibial Band Syndrome