Orthopedics Hip & Knee Kneecap (Patella) Conditions Overview of Patellar Tendon Tear Tears Typically Require Surgical Repair By Jonathan Cluett, MD twitter linkedin Jonathan Cluett, MD, is a board-certified orthopedic surgeon with subspecialty training in sports medicine and arthroscopic surgery. Learn about our editorial process Jonathan Cluett, MD Medically reviewed by Medically reviewed by Stuart Hershman, MD on June 21, 2020 linkedin Stuart Hershman, MD, is a board-certified spine surgeon. He specializes in spinal deformity and complex spinal reconstruction. Learn about our Medical Review Board Stuart Hershman, MD on June 21, 2020 Print Table of Contents View All Symptoms Causes Diagnosis Treatment Recovery and Prognosis The patellar tendon is the structure that connects the kneecap (patella) to the shinbone (tibia). A ligament is a structure that connects one bone to another bone, and therefore some people refer to this as the patellar ligament. However, this structure is really connecting the quadriceps muscle to the shin bone, and a tendon connects muscle to bone, and therefore patellar tendon is the more common description. The patellar tendon is an important part of the extensor mechanism of the lower extremity. The extensor mechanism includes the quadriceps muscle, quadriceps tendon, patella (kneecap), and patellar tendon. These structures function together to allow the knee to straighten, and can do so with significant force. The extensor mechanism is critical to normal functions ranging from walking and stair climbing to athletic activities including running and kicking. Without an intact extensor mechanism, all of these activities can become difficult to perform. Illustration by JR Bee, Verywell Patellar Tendon Tear Symptoms The typical individual who sustains a torn patellar tendon is a young, male athlete. As more middle-aged people are remaining physically active, this injury is becoming more common in an older population. The injury usually involves an awkward landing from a jumping position where the quadriceps muscle is contracting, but the knee is being forcefully straightened. This is a so-called eccentric contraction and places tremendous stress on the tendon. Athletes who sustain the injury may feel a snapping or popping sensation and will typically be unable to walk following the injury. The typical signs of a torn patellar tendon include:Pain directly under the kneecapSwelling and bruising in the front of the kneeA defect, or soft spot, where the tendon should be tightDifficulty walking or doing sports activities Causes It has been found that in nearly all patients who sustain a patellar tendon rupture there is abnormal tendon tissue consistent with a chronic tendinosis. The patellar tendon is usually injured in the watershed region of the tendon, where blood flow to the tissue is poor, and the tendon is weakest. Tendon tears can also occur in non-athletic settings. Usually, there is a reason for the patellar tendon to be weakened in these individuals, such as a systemic disease that weakens tendons or recent surgery on the knee the caused tendon weakening. Treatment is usually similar in athletes and non-athletes alike. Diagnosis Making the diagnosis of a torn patellar tendon is usually obvious on clinical examination. People who tear the tendon will be unable to extend their knee against gravity, and unable to perform a straight leg raise test. The examiner can usually feel the gap in the tendon, just below the kneecap. An X-ray will be obtained, as a patellar fracture can cause similar symptoms, and should be excluded as a possible diagnosis. On the X-ray, the patella is usually up higher when compared to the opposite knee, as the quadriceps pulls up on the kneecap, and nothing is holding it down in its normal position. While often not needed, an MRI may be used to confirm the diagnosis and inspect the knee for any other damage that may have occurred. Treatment A torn patellar tendon does not heal well on its own, and left untreated will lead to weakness of the quadriceps muscle and difficulty with routine activities, including walking. Surgery to repair the torn tendon is relatively straightforward in concept but can be difficult to perform. The torn ends of the tendon need to be sewn together. The difficulty lies in the fact that it is important to restore proper tension to the tendon, not making it too tight or too loose. Also, it can be difficult to get a good repair, especially if the tendon has torn directly off the bone. In these situations, the sutures used to repair the tendon may have to be attached directly through the bone. Recovery and Prognosis Recovering from a torn patellar tendon is difficult and takes time. One of the most important prognostic factors for recovery is the time to surgery, and surgery delayed beyond a few weeks can limit recovery ability. It is known that early mobility after surgery, protected strengthening, and preventing excessive stress on the repair will speed overall recovery. Even with these steps, there is a minimum of three months until the return of normal daily activities, and four to six months until sports should be resumed. While most people heal completely from a patellar tendon surgery, there can be long-term weakness even with a successful repair. Athletes who are attempting to return to competitive sports may take a year or longer to return to their preinjury level of function. Performing guided physical therapy can be helpful to ensure athletes are able to resume their normal sports activities. Was this page helpful? Thanks for your feedback! Dealing with joint pain can cause major disruptions to your day. Sign up and learn how to better take care of your body. Click below and just hit send! Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Matava MJ. Patellar tendon ruptures. J Am Acad Orthop Surg. 1996;4(6):287-296. doi:10.5435/00124635-199611000-00001 Wilson JJ, Best TM. Common overuse tendon problems: A review and recommendations for treatment. Am Fam Physician. 2005;72(5):811-8. American Academy of Orthopaedic Surgeons. Patellar Tendon Tear. OrthoInfo. Additional Reading Matava MJ. "Patellar Tendon Ruptures." J Am Acad Orthop Surg November 1996 vol. 4 no. 6 287-296.