Quadricep Tendon Rupture

You're heading down a steep trail at Mount Si or catching yourself on the stairs at home when suddenly — pop. Sharp pain hits just above your kneecap, and your leg gives out. If you can’t straighten your knee afterward, you might have torn your quadriceps tendon — the thick band that connects your thigh muscles to your kneecap.

These injuries usually happen when the quad muscle contracts forcefully while the knee is bent — common during hiking, running downhill, or misstepping off a curb. People over 40 are more at risk, especially if they’ve had knee issues before or take certain medications that weaken tendons.

Most people feel a sudden pop, followed by swelling, pain, and an inability to straighten the leg. Walking becomes difficult, and in some cases, you may feel a gap just above the kneecap where the tendon pulled away.

Partial tears can sometimes heal with rest and rehab, but complete ruptures almost always need surgery. The tendon must be reattached to the bone so the leg can function properly again. The sooner it’s treated, the better the outcome.

If you’ve had a knee injury and can’t extend your leg, don’t wait it out. At Ortho Compass, we connect people in the Pacific Northwest with top orthopedic surgeons — no referral required.