Knee Pain: Understanding the Causes and Solutions

The knee is a complex joint that works with every step. It connects the femur, tibia and kneecap, while involving the ligaments, menisci, cartilage, tendons and muscles that ensure the stability of the lower limb.

Knee pain can appear after a fall, a twist, an awkward movement, a sports injury or repetitive movements. It can also develop gradually, particularly due to poor biomechanical alignment, overload, joint instability or a condition such as knee osteoarthritis.

It is important to understand the source of the pain, whether it is felt at the front, on the side, on the inside, at the back or throughout the knee joint.

Pain at the front of the knee is often felt around the kneecap or just below it. It can occur when walking, running, doing squats, jumping, going up or down stairs, or after sitting for a long period with the knees bent.

Patellofemoral syndrome

Patellofemoral syndrome, also known as femoropatellar syndrome, is characterized by irritation between the kneecap and the femur. The pain is usually felt at the front of the knee, around or behind the kneecap.

It can appear after physical activity, then become more frequent if the problem is not addressed. Some people also experience cracking sounds, discomfort on stairs or pain when sitting for a long time.

This syndrome can be caused by overuse of the joint, hypermobility of the kneecap or poor biomechanical alignment. In some cases, hyperpronation of the foot, meaning excessive inward collapse of the arch, changes the path of the kneecap and increases stress on the knee.

Patellar tendinitis

Patellar tendinitis affects the tendon located between the kneecap and the tibia. It is often associated with repetitive movements, jumping, running or increasing training intensity too quickly.
The pain usually appears under the kneecap, at the front of the knee. It may be more noticeable during activity, when using stairs, bending the knee or after sustained effort.

Pain on the side of the knee can be felt on the inside or outside of the joint. It can occur after a twist, pivot, impact, fall or repetitive activity.

Depending on the symptoms, this type of pain may be related to the collateral ligaments, the meniscus, the iliotibial band or a misalignment of the lower limb.

Knee sprain

A knee sprain is a ligament injury that occurs when a ligament is stretched or torn. It can affect different knee ligaments, such as the medial collateral ligament, lateral collateral ligament, anterior cruciate ligament or posterior cruciate ligament.

Symptoms may include sharp pain, swelling, a feeling of dislocation, knee instability, difficulty putting the foot on the ground or the impression that the knee is “giving way.”

Pain at the back of the knee may be felt when walking, extending the leg, standing for long periods or after physical effort. It may be related to muscle tension, loss of range of motion or an alignment issue.

Genu recurvatum

Genu recurvatum refers to hyperextension of the knee. The joint opens too far backward, which can change the alignment of the leg and increase stress on the soft tissues.

This condition can cause pain, stiffness, a feeling of instability or fatigue when walking and standing. Over time, it can contribute to early tissue deterioration if the joint is not properly controlled.

Genu flexum

Genu flexum refers to a knee that does not fully straighten. This limitation in extension can affect gait, cause limping and lead to discomfort in the knee, leg or other joints.

The pain may be accompanied by stiffness, loss of range of motion and difficulty walking for long periods. A knee that remains bent also requires more effort from the muscles, which can increase daily fatigue.

Other common knee conditions

Some knee pain is not limited to a specific area. It can affect the entire joint, progress gradually and be accompanied by stiffness, swelling, instability or loss of mobility.

Knee osteoarthritis

Knee osteoarthritis, also known as gonarthrosis, is a condition that causes progressive deterioration of the joint cartilage. When the cartilage wears down, the bone surfaces are less protected, which can cause pain, stiffness and swelling in the knee.

The pain is often felt when walking, going up or down stairs, moving from a seated to a standing position or after an active day. In more advanced stages, osteoarthritis can reduce range of motion and interfere with daily activities.

Knee instability

Knee instability gives the impression that the joint is less solid, moves too much or may “give way” while walking, using stairs or doing physical activities.

It may be related to ligament damage, muscle weakness, hypermobility or poor alignment of the lower limb. When the ligaments do not hold the joint as well, the risk of injury may increase.

Genu valgum

Genu valgum is recognized by an X-shaped misalignment of the legs. The knees tend to move inward, which changes how loads are distributed across the joint.

This condition is not always painful, but it can contribute to certain knee discomforts, especially when walking, running or standing for long periods. It can also create mechanical stress that, over time, increases the risk of pain or osteoarthritis.

Genu varum

Genu varum is a deformity characterized by bowed legs that are aligned outward. Like genu valgum, it can change how loads are distributed within the joint.

It is not necessarily painful, but it can become uncomfortable if certain parts of the knee are placed under greater stress. Over time, this misalignment can be associated with the onset or worsening of knee osteoarthritis.

Soothe your knee pain and regain lasting comfort

Tired of limiting your movements, activities or outings because of knee pain? Persistent pain should not prevent you from walking, working, climbing stairs or enjoying the activities that make you feel good.

At one of our Médicus branches, our orthotists support you in assessing your needs and better understanding the mechanical factors contributing to your pain. When needed, a biomechanical evaluation can help observe your posture, gait and the alignment of your feet, knees and lower limbs in order to identify the solutions best suited to your condition.