Quadriceps tendonitis is inflammation of the tendon of the quadriceps (thigh) muscle, where it inserts at the top of the patella and is responsible for the forceful extension of the knee.
While the different muscle parts originate from different structures, the quadriceps tendon attaches to the tibial tuberosity, which is prominently located on the shin.
The patella is embedded in the quadriceps tendon. The quadriceps tendon continues from the patella as the ligamentum patellae. Inflammation of the quadriceps tendon usually occurs at the transition to the bone, i.e., where the tendon starts at the upper pole of the patella, rises at the lower pole, and ends at the tibia.
Check our article about Shin bruise, causes, symptoms and treatment
Causes of quadriceps tendonitis
Quadriceps tendonitis usually results from chronic overloading of the tendon and all structures connected to it. Chronic overloading occurs mainly during regular jumping, playing sports, or running, but also during professional activities that are mainly performed while kneeling, such as tiling.
Due to the heaped and strong contraction of the quadriceps muscle, an enormous tension is, in principle, applied continuously to the quadriceps tendon and the connected bone attachment.
Besides, an axial misalignment, such as bow legs, can negatively influence the traction of the quadriceps tendon, which puts more strain on it. The effect of force is most significant at these tendon-bone boundaries, which is why inflammation tends to occur there.
In the course of chronic inflammation, metabolic processes can lead to calcification of the tendon, which in turn leads to pain and degeneration, i.e., wear and tear, of the tendon apparatus.
If the quadriceps tendon is already too severely affected and damaged by the inflammation process, it can no longer withstand the high forces during movement, and tears can occur. In the worst case, a partial – or even complete rupture of the quadriceps tendon follows as a result of the inflammation.
Check our article about Patellofemoral Pain Syndrome: Causes, Symptoms, and Treatment
Diagnosis of quadriceps tendonitis
Besides the physical examination, imaging techniques are also used for diagnosis. The diagnosis of quadriceps tendonitis is initially made according to the clinical picture. This means that the patient visits a doctor because he or she has noticed pain or a restriction in the movement of the knee, and the doctor then characterizes the symptoms precisely based on a physical examination and a medical history. The focus is mainly on the point where the quadriceps tendon attaches to the kneecap and the tibia. There, the pressure pain can typically be localized to a single point, in some cases, even swelling, hardening due to calcification of a dent after the tendon has been torn.
Besides, various tests can be used to determine the strength and function of the quadriceps tendon during knee extension in order to define the extent of the inflammation.
It is essential to differentiate between the two, as the knee joint itself is not impaired in its function. A detailed anamnesis can provide additional information on the development of the inflammation, its course, and symptoms.
Furthermore, imaging measures can be performed, such as an ultrasound of the quadriceps. In this way, the tissue of the tendon can be well assessed with the question of inflammation or rupture.
Typical signs of quadriceps tendonitis are calcification, water retention, loss of smooth boundaries of the tendon fibers, or ruptures.
Alternatively, a lateral x-ray of the knee can be taken, again looking for calcification in the quadriceps tendon. To clarify a rupture of the tendon, an MRI image of the knee is made, since this allows a better differentiation of the soft tissue of the quadriceps tendon and thus also determines the thickness.
The quadriceps tendonitis becomes apparent to the affected person primarily through a point-like pressure pain exactly above the corresponding tendon section. The inflammation and thus the pressure pain typically occurs at three points: Either at the upper edge of the patella, the lower edge, or the tibial tuberosity of the tibia.
This pressure pain, which is caused by the quadriceps tendonitis, may well lead to pain during movement, especially during the triggering overloading, which results in a restriction in the knee’s freedom of movement. In contrast, the knee itself is not functionally impaired.
Check our article about Knee Plica Syndrome: Causes, Symptoms, and Treatment
Therapy of quadriceps tendonitis
Conservative therapy may be considered at the beginning to treat quadriceps tendonitis. First of all, the overloading of the quadriceps tendon, which is one of the leading causes of inflammation, should be reduced to a minimum. Only when this stressor is removed can the inflammation of the quadriceps tendon regress and heal.
Local physiotherapy can, on the one hand, promote healing and, on the other hand, increase the durability of the tendon to prevent future inflammation due to overloading. Besides, it is also possible to counteract incorrect loading of the quadriceps tendon by learning new, gentler movement sequences. Part of the conservative therapy should include anti-inflammatory and pain-relieving medication. On the one hand, the drugs should reduce the patient’s suffering from the painful inflammation of the quadriceps tendon and make pain-free movement possible again. On the other hand, they should promote recovery by suppressing the inflammatory reaction.
If conservative therapy fails and chronic complaints arise from the quadriceps tendonitis, surgical intervention may be considered. However, this does not serve to treat the inflammation but is intended to relieve the pain caused by the inflammation by removing possible calcium. Also, a torn or partially torn quadriceps tendon can be reconstructed during surgery. Cutting out the inflamed area is not advisable as this would not give a better result, and the function of the tendon would be lost.
As a rule, conservative therapy, especially reduced strain, is very helpful.
To counteract quadriceps tendonitis, it is recommended to avoid overloading the quadriceps tendon in particular if there is sufficient physical activity. This does not automatically mean that no more sports should be practiced, but that triggering movements should only be carried out in moderation. It can also help to increase the load capacity of the quadriceps tendon in advance through targeted stretching exercises.
Quadriceps tendonitis can be very persistent and protracted in therapy. Nevertheless, one should try to positively influence the healing and regeneration process of the quadriceps tendon through the therapy mentioned above options in order to enable pain-free mobility and load again.
You can also check other articles about Knee pain and conditions, causes and treatment
- Kuster M, Sakurai S, Wood GA. Kinematic and kinetic comparison of downhill and level walking. Clin Biomech (Bristol, Avon) 1995;10:79–84. [PubMed] [Google Scholar]
- Lay AN, Hass CJ, Gregor RJ. The effects of sloped surfaces on locomotion: a kinematic and kinetic analysis. Journal of biomechanics. 2006;39:1621–8. [PubMed] [Google Scholar]
- McIntosh AS, Beatty KT, Dwan LN, Vickers DR. Gait dynamics on an inclined walkway. Journal of biomechanics. 2006;39:2491–502. [PubMed] [Google Scholar]
- Kuster M, Wood GA, Sakurai S, Blatter G. 1994 Nicola Cerulli Young Researchers Award. Downhill walking: a stressful task for the anterior cruciate ligament? A biomechanical study with clinical implications. Knee Surg Sports Traumatol Arthrosc. 1994;2:2–7. [PubMed] [Google Scholar]
- Liikavainio T, Isolehto J, Helminen HJ, Perttunen J, Lepola V, Kiviranta I, et al. Loading and gait symmetry during level and stair walking in asymptomatic subjects with knee osteoarthritis: importance of quadriceps femoris in reducing impact force during heel strike? Knee. 2007;14:231–8. [PubMed] [Google Scholar]
- Astephen JL, Deluzio KJ. Changes in frontal plane dynamics and the loading response phase of the gait cycle are characteristic of severe knee osteoarthritis application of a multidimensional analysis technique. Clin Biomech (Bristol, Avon) 2005;20:209–17. [PubMed] [Google Scholar]
- Schipplein OD, Andriacchi TP. Interaction between active and passive knee stabilizers during level walking. J Orthop Res. 1991;9:113–9. [PubMed] [Google Scholar]