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Quadriceps Tendonitis: Symptoms, Causes and Diagnosis

Minute Read


Posted 1 year ago


Last updated: 29/11/2022


by James McCormack

Quadriceps tendonitis is an overload or overuse of the quadriceps tendon. The location of the quadriceps tendon is at the front of the knee joint. This tendon attaches the quadriceps muscle group to the top of the kneecap, called the patella. The quadriceps group of muscles is comprised of the vastus laterals, vastus medialis, vastus intermedius and rectus femoris. Therefore, sometimes this tendonitis is called rectus femoris tendonitis or quadriceps femoris tendonitis.

What Causes Quadriceps Tendonitis?

Quadriceps tendonitis is caused if an overload occurs acutely or chronically. Without adequate recovery time for the tendon to strengthen and adapt to tolerate the load, it will develop into a degenerative tendon or tendonitis.

The quadriceps is the main muscle group to straighten the knee so is used for many activities such as walking, running, jumping and squatting. Therefore, participating in sports that incorporate these movements with high force, speed or repetition, such as basketball or volleyball, will mean it is more likely to develop this condition. These types of sports require powerful contraction of the quadriceps to create the force to jump or sprint. As well as good control and absorption of the energy on landing. Hence, why this injury is often referred to as Jumper’s knee. The tendon therefore must be well conditioned to manage these forces. As well as be given adequate recovery time after to repair any microdamage that may have occurred during use.

In this sporting population, there is an increased incidence of quadriceps tendonitis in men as compared to women. Younger age, greater height and weight of the individual, as well as greater volumes of strength and jumping training also increase incidence (King et al, 2019).

There is an increased risk of this injury developing with some postures and movement patterns. Movements such as excessive knee bend when walking or running, overpronation, and poor foot posture or valgus knees (turning in). With some specific physiology, it is also more common, such as plica. Plica are folds in the synovial membrane which can block the movement of fluid in the knee and cause an irritation of the tendon.

In the non-athletic community, quadriceps tendonitis does also exist. Activities such as kneeling can also overload this area. And there are some medical conditions that can change tendon structure or load. People with diabetes have a threefold increased risk of all musculoskeletal conditions, but are particularly vulnerable to tendon conditions, which are more treatment-resistant than in patients without diabetes.” (Baskerville et al, 2018). This is because diabetes can change the structure of tendons which can cause it to be less able to tolerate load.

“Obesity is associated with a higher risk of tendinopathy, tendon tear and rupture, and complications after tendon surgery than non-obesity.” (Macchi et al, 2020). This is due to higher levels of inflammatory proteins than non-obese individuals, as well as the greater mechanical load on the joints. Obesity is also associated with the development of type 2 diabetes.

Quadriceps Tendonitis Symptoms

In most cases, there is a gradual onset of discomfort at the front of the knee, at the top of the patella, at the tendon attachment. This can occur in both knees concurrently. Many people will tolerate this low-level pain and continue with their sports or activities for months. Once persistent for longer than 3 or 4 months this can be described as a chronic quadriceps tendonitis. In some cases, pain can develop suddenly, usually if there has been an abrupt increase of load or a sudden and direct impact to the area. Commonly this will be the impact from a fall on the knee or being hit by a ball or bat. A rapid increase in the volume of a specific activity or training, such as jumping or sprinting, can also trigger this. This would be described as an acute quadriceps tendonitis.

The pain of a quadriceps tendonitis is usually described as a soreness or ache and in more severe cases can be extreme, sharp, or burning. Pain is usually most significant at the insertion of the tendon to the bone at the top of the patella. But can be felt up into the low and mid part of the thigh, in the main part of the quadriceps muscle.

Diagram showing Quadriceps Tendonitis pain location

Secondary to the pain, many people report stiffness at the knee and the quadriceps muscle may feel tight. Some describe it like they can’t bend their knee. Some also feel and hear a cracking or popping sensation when they bend and straighten their knee. Occasionally there can be swelling around the attachment area of the tendon to the patella. This is more common in acute cases of impact.

In the initial stages and in milder cases, the pain will be intermittent. Symptoms are usually felt after exercise or activity that aggravates the tendon, and there can be a delay of several hours. Pain can last for a few hours or days before easing off if the area is rested. In more severe cases or if aggravating activities are continued the pain can become more continuous. Careful monitoring of the pain or the keeping of a pain diary can help identify patterns, and indicate which activities might be aggravating the pain.

Read about Quadriceps Tendonitis Exercises.

Quadriceps Tendonitis Differential Diagnosis

Clinical diagnosis is made with a combination of assessment methods to rule in the condition with common symptom patterns associated with patella tendinopathy. Symptoms such as, pain above the patella, pain worse during and after sport, pain to touch the top border of the patella (which would suggest insertional tendinopathy), or the upper portion of the quadriceps tendon.

Importantly, clinical assessment must rule out other causes of anterior knee pain. It is uncommon for there to be locking, giving way, bruising or diffuse swelling around the knee joint. These symptoms may indicate a different diagnosis. There are further orthopaedic ‘special tests’ that can be done to rule in or out a quadriceps tendonitis or other conditions.


In some cases, radiology imaging is necessary or at least desirable to confirm the diagnosis. This is best done with MRI or diagnostic ultrasound. Both will show swelling and inflammation, the presence of bursitis, collagen breakdown, development of new blood vessels or calcific changes. All of which are physiological changes that are commonly seen at different stages of tendinopathy. X-ray imaging is less sensitive and many of these changes will not be seen, but it can be useful to rule out arthritis, and it will show calcification.

Read about Quadriceps Tendonitis Treatment.

Is tendonitis serious?

Tendonitis and tendinopathy are very common and can cause significant discomfort and restriction of participation in sports and specific activities. This restriction can last for a prolonged period of time. However, it is uncommon for there to be serious damage or rupture. Rupture is more likely to occur with individuals on specific medication such as steroids, or with specific medical conditions such as diabetes or obesity.

What does tendinopathy feel like?

With a quadriceps tendinopathy/tendonitis you will feel discomfort, soreness or an ache at the base of the quadriceps muscle where the tendon inserts into the patella. In more severe cases, it can be extreme pain, sharp, or burning and can feel stiff. It may feel it is difficult to bend your knee.

Tendonitis or tear?

An important part of diagnosis is to determine if your knee pain is in fact quadriceps tendonitis or a tear in the quadriceps tendon or muscle. Commonly with a tear, you will feel a sudden onset of pain with swelling and bruising local to the area of pain. There might also be a palpable gap in the muscle. With tendonitis, it is unlikely to have much swelling or bruising and there will be no gap to palpate.

Physiotherapy with James McCormack

This is not medical advice and we recommend a consultation with a medical professional such as James McCormack to achieve a diagnosis. He offers Online Physiotherapy Appointments for £45.

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