Overview
what it is and why it mattersThe patellar tendon is the thick rope of tissue that runs from the bottom of your kneecap to the bump on the front of your shin, the bottom half of the chain that lets you straighten your leg. A rupture is when that tendon tears all the way through. It usually happens to people under 40 (older patients tend to tear the quadriceps tendon above the kneecap instead). The injury comes from a sudden, hard load on the tendon (a stumble in sport, a missed step, a hard landing) that overwhelms it. A tendon already worn down by chronic tendinopathy is much more likely to give way.
Symptoms
what you may noticeA sudden pop or tearing sensation just below the kneecap during a hard landing, sprint, or stumble. Immediate pain and swelling in the front of the knee, and you cannot straighten your leg or lift it off the ground.
You may feel a gap or soft spot just below the kneecap where the tendon used to be taut. The kneecap may ride higher than normal because the tendon below it is no longer anchoring it down. Walking is difficult or impossible without the leg buckling.
Diagnosis
exam first, imaging secondSudden pain below the kneecap, the inability to straighten your leg or lift it off the bed, and often a noticeable gap you can feel just below the kneecap. A side X-ray shows the kneecap riding higher than normal, because the tendon below it is no longer pulling it down. An MRI confirms the rupture and shows where in the tendon it tore.
How We Treat It
how care progressesWhat we recommend depends on one question above all others: can you still straighten your leg? That single finding splits the two paths below.
1
Partial Tear: Care Without Surgery
The only cases we treat without surgery are partial tears where you can still straighten your leg. If the tendon is torn but still doing its job, there is room to let it heal without an operation.
2
Complete Tear: Surgery, and Soon
There is no good non-surgical option for a complete rupture. When the tendon has torn all the way through, you lose the ability to straighten your leg, and the repair belongs in the operating room. The timing matters, which is the focus of the next section.
Surgical Options
if non-operative care isn't enoughA complete rupture needs surgery, and sooner is better. The longer you wait, the more the torn ends pull back into the leg and shorten, and the harder it becomes to stitch them back to where they belong.
Frequently Asked
questions we hear in clinicHow do I know if the tendon is completely torn?
The telltale sign is that you cannot straighten your leg or lift it off the ground. You may also feel a gap or soft spot just below the kneecap where the tendon used to be taut, and the kneecap may ride higher than normal. If a partial tear still lets you straighten the leg, that points toward a different path.
Can a patellar tendon rupture heal without surgery?
A complete rupture does not have a good non-surgical option. The only cases we treat without surgery are partial tears where you can still straighten your leg. A tendon torn all the way through needs to be repaired in the operating room.
Does it matter how quickly I have surgery?
Yes. Sooner is better. The longer you wait, the more the torn ends pull back into the leg and shorten, which makes it harder to stitch them back to where they belong.
Who tends to get this injury?
It usually happens to people under 40. Older patients tend to tear the quadriceps tendon above the kneecap instead. A tendon already worn down by chronic tendinopathy is much more likely to give way.
Will I need an MRI?
The diagnosis starts with the exam: sudden pain below the kneecap, the inability to straighten or lift the leg, and often a gap you can feel. A side X-ray shows the kneecap riding higher than normal. An MRI confirms the rupture and shows where in the tendon it tore.
Providers Who Treat Patellar Tendon Ruptures
sports-medicine team
Further Reading
authoritative sourcesExternal patient-education references and related OSI pages for additional background: