Quadriceps Tendonitis: Everything You Need to Know

Although less common than patellar tendonitis, quadriceps tendonitis is an important cause of quad pain above kneecap. So, how do we diagnose quadriceps tendon pain, and what can we do about it?

What is the quadriceps tendon? 

The quadriceps tendon attaches the large quadriceps muscle to the top of the kneecap (or patella). This large tendon transfers forces from the lower leg and foot to the trunk, like the patellar tendon.

Causes of quadriceps tendonitis 

Like the Achilles and patellar tendons, the large quadriceps tendon undergoes swelling and collagen breakdown with an excess load. Usually, we see quadriceps tendon pain in popular jumping sports such as CrossFit, rugby, and volleyball. Generally, there is a history of a sudden increase in training frequency or intensity, leading to quad tendon swelling and breakdown. In addition, we see this condition in older active people with calcification of the quadriceps tendon. We know that calcification causes quadriceps tendon pain and irritation.

In some cases of quadriceps tendinopathy, the tendon swelling is caused by a suprapatellar plica. This plica can block the movement of knee fluid, leading to pressure in the top part of the knee. This pressure can lead to quadriceps tendon swelling and tendonitis. In an observational study co-authored by Dr Masci, seven active athletes with intractable quadriceps tendonitis underwent arthroscopic surgery. All seven cases had a large suprapatellar plica separating the suprapatellar pouch from the rest of the knee joint. We suspect a sizeable suprapatellar plica that separates the top from the bottom leads to a build-up of pressure in the knee joint. We hypothesise that higher pressure in the knee joint leads to altered forces on the quadriceps tendon, increasing the risk of tendonitis. 

Diagnosis of quad tendonitis

Generally, common symptoms of quadriceps tendon pain include:

1. Quad pain above the kneecap that is worse during and after activity.

1. Often, there is no swelling, locking, or giving away of the knee.

1. It is often tender to touch the quadriceps tendon.

Your doctor will perform a clinical examination to rule out other causes of pain above the kneecap or at the front of the knee, such as kneecap arthritis, fat pad impingement, torn meniscus, pes bursitis,  housemaid’s knee, and patellar tendonitis.

Often, we use imaging to diagnose quad tendonitis and rule out other causes. Usually, ultrasound and MRI scans can see changes in swelling and collagen breakdown of the tendon. Ultrasound has advantages over MRI scans, including seeing calcification more clearly and at a lower cost.

Treatment 

Overall, we use simple treatments first for this condition. Some treatments include activity modification (reducing jumping training), soft tissue massage to the leg, anti-inflammatory tablets such as ibuprofen, and strengthening exercises.

Quadriceps tendonitis exercises

Generally, strengthening exercises targeting the quadriceps muscle improve quad pain above the knee. A physical therapist should supervise these exercises. Exercises for quadriceps tendonitis include weighted squats, lunges, hack squats, leg press and leg extensions. Generally, we recommend single-leg exercises rather than double-leg.

If simple treatments fail, we often use other therapies to help. These different treatments include GTN patches, shockwave therapy, or tendon injections.

Shockwave and needle tenotomy injections are particularly effective if calcification occurs in the quadriceps tendon. 

Finally, surgery should only be reserved for cases that fail all other treatments. Open tendon surgery to remove degenerative tendons is often unsuccessful. Other options include knee arthroscopy to excise a suprapatellar plica. A recent observational study found seven athletes with intractable quadriceps tendonitis had a large suprapatellar plica. Removal of the plica led to significantly improved symptoms and a full return to sport. We suggest consideration of an arthroscopy for intractable quadriceps tendonitis that has failed other treatments.  

More on injections for quadriceps tendonitis 

Injections for quadriceps tendons are invasive treatments and introduce an element of risk and unpredictability. While injections can help with complex cases of quad pain above the knee, they should only be performed after you try non-invasive treatments such as exercise and shockwave.

There are a few options for injection therapy.

Cortisone injections are sometimes harmful and should be avoided. Needle tenotomy is thought to stimulate inflammation and encourage healing. Finally, some doctors use platelet-rich plasma to promote healing. However, while there is some evidence for PRP treatment for tennis elbow, there is little evidence for quad pain above kneecap.

Generally, we recommend a needle tenotomy for quadriceps tendon calcification to break down the calcification. Sometimes, we use a small dose of cortisone to help dissolve the calcification after needle breakdown.

Ususally, we usually recommend using ultrasound to improve accuracy and ensure the injection hits the right spot.

Final word from Sportdoctorlondon about quadriceps tendonitis

Quadriceps tendonitis is a less common cause of pain at the front of the knee. Often, there is focal quad pain above the knee. Nevertheless, the treatment of this condition follows the general principles of tendon treatment. We suggest GTN patches or shockwave therapy followed by injections in complex cases. Surgery is only a last resort.

Related conditions:

• Kneecap arthritis 
• Quadriceps muscle tear
• Dead leg thigh 
• Thigh nerve pain