Crack in the lower right when lifting the leg

Quadriceps tendon tear and patellar tendon tear

Quadriceps tendon tear (Quadriceps rupture) or Patellar tendon tear (Patellar tendon rupture): Tear of the tendon above the kneecap (quadriceps tendon) or the ligament below the kneecap to the lower leg bone (patellar tendon or ligamentum patellae). The injury disrupts the stretching apparatus of the leg. Smaller tears can be treated in a special splint without surgery, while complete tears always require a suture. No lasting consequences are to be expected.

Leading complaints

  • Often noticeable crack
  • Then moderate pain above or below the kneecap
  • In the beginning often palpable dent above or below the kneecap, later more swelling
  • Walking is usually still possible, but there is a significant loss of strength when stretching the knee (e.g. when climbing stairs) and when lifting the lower leg while sitting or lying down.

When to the doctor

Immediately for any pain in the kneecap area that follows a noticeable crack.

The illness

The quadriceps tendon arises from the lower end of the strong front thigh muscles (quadriceps muscle). It starts at the upper pole of the kneecap, runs as a thick cord over the front of the kneecap and finally merges into the patellar tendon that connects the lower pole of the kneecap with the front of the tibia. The quadriceps and patellar tendons, like the kneecap, are part of the extensor system that transfers the forces of the quadriceps muscle to the lower leg. Although they have to withstand strong tensile forces, their solid structure protects them from cracks in their normal state. These only occur on tendons that have already been damaged, for example as a result of metabolic disorders, e.g. Diabetes, gout, repeated cortisone injections, e.g. B. for the treatment of a runner's knee, graft removal, z. B. in operations for a cruciate ligament injury or repeated, minor injuries that may have gone unnoticed. It therefore mainly affects older or physically active people. The direct cause is always a direct or indirect force that often seems banal. When jogging, for example, stepping into a depression can lead to a sudden peak load and thus cause a crack.

That's what the doctor does

The doctor will usually recognize the tear by palpating the tendons, especially when compared to the opposite side. The position of the kneecap provides an important indication: If the quadriceps tendon is torn, it is lower, and if the patellar tendon is torn, it is higher than on the uninjured side. An ultrasound or nuclear spin makes the interruption of the tendon visible. X-ray examinations are only necessary to rule out an accompanying fracture of the kneecap or a bony tear at the tendon insertion.

In the case of smaller tears in the tendons that have not been damaged or have not been damaged, the patient is given a splint that he wears until the pain and swelling have subsided. With subsequent physiotherapy, the injury is usually so far healed within 3 months that it allows normal sporting activities again.

Complete tendon tears always require an operation, as the tendon stumps diverge and therefore do not allow healing, which leads to sufficient stability and function of the extensor system. The operation should be carried out as quickly as possible, as the increasing retraction of the torn tendon parts makes the operation more difficult and worsens the achievable end result. After the crack has been sewn using a special technique (braided seam), a follow-up treatment phase begins with physiotherapy and splints. After 3 months, the knee joint is usually fully resilient again (athletically).


Dr. med. Martin Schäfer, Dr. med. Arne Schäffler in: Gesundheit heute, edited by Dr. med. Arne Schäffler. Trias, Stuttgart, 3rd edition (2014). Revision and update: Dr. med. Sonja Kempinski | last changed on at 15:49

Important note: This article has been written according to scientific standards and has been checked by medical professionals. The information communicated in this article can in no way replace professional advice in your pharmacy. The content cannot and must not be used to make independent diagnoses or to start therapy.