When should you not delay getting tested?

Although rest may provide temporary relief, a diagnosis by a specialist is essential if certain symptoms are present:

• Mechanical obstruction: If the knee suddenly “locks up” or cannot be fully extended (this often indicates a loose piece of cartilage or a meniscus rupture).
• Instability: If you feel like the joint is “giving way” or cannot support your weight (suspected ligament injury).
• Signs of inflammation: If your knee is red, hot, and you have a fever (this may indicate an infection-related inflammation, which requires immediate medical attention).
• Progression: If the pain does not subside with rest or interferes with sleep at night.

Identifying the exact cause of knee pain is the first and most important step. The goal of modern orthopedics today is not only to relieve pain but also to preserve joint function. Whether it involves specialized, targeted physiotherapy, biological therapies (such as autologous blood injections), or minimally invasive surgery, the goal remains the same: to restore your freedom of movement.

You don’t have to put up with the pain; with an accurate diagnosis, there is always a path to recovery.

2. Pain on the inner side of the knee

If the pain is localized on the inner side of the knee, it usually indicates overuse of the weight-bearing surfaces. During walking, a significant portion of a person’s body weight is borne by the inner joint surface, which is why this area wears down the fastest.

The most common cause is an injury to the medial meniscus (ring-shaped cartilage). This small, “C”-shaped piece of cartilage acts as a shock absorber. If it tears or degenerates, the pain is sharp and localized. You may often find that your knee “locks up” during certain movements, or you may feel as if there is a pebble in the joint.

In the long term, cartilage degeneration also occurs here, which is particularly common among people with “bowlegs.” In this case, the pain is dull and “start-up” in nature (it’s harder to get moving in the morning), and then intensifies by the end of the day due to the strain.

3. Pain on the outer (lateral) side of the knee

We see wear and tear less frequently on the outer side of the knee; here, symptoms are more often caused by dynamic conflict between the ligaments and tendons.

The most well-known condition is IT band syndrome, also known as “runner’s knee.” The broad band of connective tissue running along the outer side of the thigh constantly moves over the lateral condyle of the femur as the knee bends and straightens. If this band is too tight, it irritates the bone surface with every step, causing a burning, rubbing pain.

Although less common, involvement of the lateral meniscus can also cause symptoms here. Because the lateral joint surface is more mobile, injuries in this area are often accompanied by pain that is more vague and harder to pinpoint than on the medial side.

4. Pain in the back of the knee

Symptoms in the back of the knee are often alarming because the patient feels a “lump” or tightness that limits full knee flexion.

The most common diagnosis is a Baker’s cyst. It is important to clarify that a cyst is almost never a disease in and of itself. It acts as a sort of “valve” through which excess fluid produced in the joint finds its way backward. If there is inflammation in the knee due to cartilage degeneration or a meniscus tear, the body produces more synovial fluid, which causes the posterior joint capsule to bulge. Therefore, when treating a cyst, we must always identify the underlying condition. In addition, irritation at the attachment sites of the hamstrings or an injury to the posterior cruciate ligament can also cause deep-seated, pulling pain in this area.

5. Diffuse symptoms: Generalized swelling and nighttime pain

There are situations when the pain isn’t localized to a single spot, but rather the entire knee feels “tight.”

When there is “fluid in the knee,” both straightening and fully bending the knee become painful due to tension in the joint capsule. In such cases, the joint feels warm, appears visibly larger, and its contours become blurred. This may indicate an acute injury, but it could also be a flare-up of inflammation (such as gout or rheumatoid arthritis).

Nighttime pain is one of the most important warning signs. If your knee aches even at rest—to the point of disrupting your sleep—it is often a sign of advanced cartilage degeneration. At this stage, the protective layer between the bone surfaces has thinned so much that the nerve endings in the bone become sensitive even to the pulsation of blood flow.