What is a patellar tendon tear?
The patellar tendon connects the bottom of the kneecap to the shin bone. It carries the pull of the thigh muscle, which is how you straighten your knee. A tear can be partial or complete. In a complete tear, also called a rupture, the thigh muscle can no longer straighten the knee.
These tears are rare. In a review of 970 patients who had repair, 93.8% were men, and the average age across studies ranged from about 32 to 45 (Dave, 2025).
This is different from jumper’s knee, a painful overuse problem in the same tendon. Jumper’s knee is usually managed without surgery. A similar tear above the kneecap is a quadriceps tendon tear.
How do I know if I tore my patellar tendon?
Many people feel a pop or tearing just below the kneecap, often when landing from a jump or when the knee is forced to bend while the thigh muscle is working hard. Swelling comes on quickly, and the knee may buckle.
The key sign is that you cannot straighten the knee against gravity or lift the leg straight off the bed. The kneecap may also sit higher than on the other side.
Get seen soon. The exam often points to the answer. X-rays can show the kneecap’s position, and an MRI or ultrasound can confirm the tear. Less often, an ACL tear happens at the same time, which changes the plan. You can read more about ACL reconstruction.
Do I need surgery?
A complete tear usually does. Left untreated, it causes severe loss of function (Dave, 2025).
A partial tear is a different conversation. If you can still straighten the knee, a brace and physical therapy may be an option. The decision rests on your exam and imaging.
Why does timely repair matter?
Once the tendon is torn, the thigh muscle pulls the kneecap upward and the torn ends can scar. After enough time, the tendon may not reach back to where it belongs. A graft may then be needed instead of a direct repair.
One review looked at ruptures treated more than four weeks after injury. It covered 96 patients who had reconstruction with their own tissue or donor tissue. Results were fair to good, with low complication rates, and the review stressed at least six weeks of immobilization afterward (Hahn, 2023).
A few days to arrange surgery does not appear to be a problem. In a series of 34 patients repaired within nine days of injury, time to surgery was not linked to knee bending at hospital discharge. That study was small and only looked at the short term (Bencharles, 2026).
So there is no need to panic, but do not wait weeks to see how it feels.
How is a patellar tendon tear repaired?
The surgeon works through an incision at the front of the knee and places strong sutures in the torn tendon. If it pulled off the kneecap, those sutures are fixed to the bone through small tunnels or with suture anchors. A tear in the middle of the tendon can be sewn end to end.
Most results do not point to one clear winner between tunnels and anchors. Only one study in a large review found a significant difference in re-rupture, at 7.5% with tunnels and 0% with anchors. The authors advised matching the technique to the patient (Dave, 2025).
In that review, average knee bending at follow-up ranged from about 129 to 143 degrees. The overall re-rupture rate was 3.9%, and the overall re-operation rate was 5.7% (Dave, 2025). Those are group averages, not a promise for any one knee.
What are the risks of surgery?
Risks include re-rupture, stiffness, blood clots, infection, and discomfort from implants. Stiffness ranged from 0% to 35% across studies. Blood clots, infection, and implant discomfort each ranged from 0% to 5% (Dave, 2025).
How soon to bend the knee is still debated. A review of 709 patients found more adverse events with early motion than with at least six weeks of fixed immobilization, though additional surgery was not significantly different (Serino, 2017). These were observational studies, so your plan should be set for your repair.
Results vary from person to person, and no surgeon can promise a certain outcome.
Should I get a second opinion?
It can help, especially if your tear was found late, or if you were told you need a graft. Here’s how a second opinion works.
Where can I see Dr. Pareek?
Dr. Pareek sees patients with patellar tendon tears at HSS in New York and at HSS in New Jersey. Bring any X-rays, MRI images, and reports you already have.
What does recovery look like?
These are typical ranges. Your surgeon’s plan comes first, and recovery varies from person to person.
- Weeks 0-2: Protect the repairMany people use crutches and a brace that holds the knee straight, with early work on swelling and wound care. Your limits on weight and bending are set for your repair.
- Weeks 2-6: Keep it protectedThe brace usually stays on while the tendon heals. Any bending is added in steps your surgeon sets, and physical therapy works on waking up the thigh muscle.
- Weeks 6-12: Walk normallyMost people move off crutches and out of the brace toward a normal walking pattern. Therapy works on knee motion and starts to build strength.
- Months 3-6: Build strengthTherapy moves toward harder thigh and hip strength and balance, then light running if your knee is ready.
- Months 6 and beyond: Return to activityJumping and sport come back in steps, once strength and testing allow. Some people need longer. These are typical ranges, and your surgeon's plan governs.
Sources
- Dave U, et al. Patellar tendon repair restores extensor mechanism function with a low complication rate: a systematic review. J Orthop 2025;66:146-153.
- Hahn AK, et al. Outcomes and complications following chronic patellar tendon repair: a systematic review. Cureus 2023;15:e41713.
- Bencharles O, et al. Clinical outcomes following repair of acute patellar tendon injuries at a tertiary trauma centre: a 16-year retrospective series. Cureus 2026;18:e111133.
- Serino J, et al. Comparison of adverse events and postoperative mobilization following knee extensor mechanism rupture repair: a systematic review and network meta-analysis. Injury 2017;48:2793-2799.