My knee won't fully straighten since I twisted it. Is it locked?

Two very different reasons

Soft block: after an injury, fluid fills the knee and the hamstrings tighten to protect it. The knee stops a few degrees short of straight, but the limit feels springy, it improves a little every day as swelling settles, and gentle pressure eases it further.

Hard block: something is physically in the way. The end point feels firm and abrupt, it does not improve with ice and time, and trying to force it causes a sharp pain deep in the knee. Common culprits are a bucket-handle meniscus tear flipped into the front of the joint, a loose fragment, or the torn stump of an ACL caught in the front of the knee.

A simple check you can do

• Sit on the floor with both legs out straight and compare the backs of the knees against the floor
• Look at whether you can lift the heel of the injured leg off the ground as far as the other leg when lying down
• Note whether the gap is getting smaller from day to day

If there is no improvement over about a week, or the gap is large from the start, book an assessment rather than waiting.

Why getting full straightening back matters

Walking with the knee slightly bent overloads the thigh muscle and the kneecap joint, causes a limp and can lead to lasting stiffness. Even a few degrees of lost extension can be noticeable on stairs and in sport. If a meniscus tear is the cause, delay can reduce the chances of repairing it.

Assessment and treatment in Doha

At Aman Hospital, Dr. Gelber measures the extension loss, feels the end point and tests the ligaments and meniscus, then usually arranges an MRI to look for a block. A soft block is treated with swelling control and a physiotherapy programme focused on regaining straightening. A hard block from a meniscus tear or loose body is usually treated with keyhole surgery, ideally soon after diagnosis. If the ACL is torn, the plan addresses both the block and the instability.