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Orthopedics · Knee

Dislocated and unstable kneecap

Has your kneecap popped out, or does it feel as if it could slip out at any moment? After a first dislocation, exercises are usually enough. If the kneecap dislocates repeatedly, surgery that stabilizes it in its groove again may help. If everything is in order, the procedure can take place as soon as within a week of the consultation.

Book an orthopedic consultation Exercises or surgery?
  • No GP referral needed
  • Surgery by Prof. MUDr. Radek Hart

Kneecap stabilization

1 weekhow soon the procedure can be
first dislocation
exercisesusually treated without surgery, with a brace
back to activities
1–3 monthsgoal after a first dislocation without surgery
until the procedure
1 weekfrom the consultation, if everything is in order
after ligament reconstruction
4 monthsrecovery usually takes

When surgery is considered

A kneecap that slips out of its groove

When you bend and straighten your leg, the kneecap glides in a groove at the end of the thigh bone. Ligaments, muscles and the shape of the bones hold it in place. The ligament on the inner side of the kneecap stops it from shifting too far to the outside. When these stabilizers are not enough, the kneecap slips out of the groove.

  1. Dislocation when twisting

    The kneecap often dislocates without any impact, when you turn, twist the knee or fall awkwardly. Sometimes a hard blow knocks it out. It often returns to its place on its own.

  2. The feeling that it will slip out

    Fear of certain movements because the kneecap feels as if it could slip out at any moment. Along with that, pain at the front of the knee, swelling and stiffness, especially after exertion.

  3. Why it keeps happening

    A damaged ligament on the inner side of the kneecap, a groove that is too shallow, a kneecap that sits too high, knock knees or twisted bones. Looser ligaments and weaker thigh muscles play a role too.

  4. A fresh dislocation

    Do not put the kneecap back yourself and do not stand on the leg. Have the knee examined at an emergency department or urgent care, even if the kneecap went back by itself. Come to us afterwards, for a further examination or when the problems return.

Cross-section diagram of the knee seen from above: on the left the kneecap in the groove of the thigh bone, held by the ligament on the inner side; on the right the kneecap dislocated to the outer side, the ligament torn and the groove empty thigh bone outer sideinner side Kneecap in its groove empty groove thigh bone outer sideinner side Dislocated kneecap
  • kneecap
  • ligament that holds the kneecap from the inner side
  • thigh bone with its groove
  • torn ligament
Simplified cross-section diagram of the knee, not an actual image.

Treatment

First without surgery, when that is enough

After a first dislocation, treatment usually starts without surgery and results are generally good; the kneecap dislocates again in only a smaller share of patients. For some people, however, the risk of it happening again is higher. The doctor assesses this at the consultation.

Step 1

Rest, cold and leg up

The first days after the dislocation.

  • Cooling for 10 to 15 minutes, at least 3 times a day, ice wrapped in a cloth
  • Leg raised when resting, crutches when walking hurts
  • Pain medication according to what you usually tolerate

Step 2

Exercises and a brace

A gradual return to loading the leg.

  • Strengthening the thigh muscles so the kneecap stays in its groove
  • Cycling is often recommended as part of the exercises
  • A stabilizing brace, physiotherapy right at the clinic

Step 3

Surgery

When the kneecap dislocates again.

  • The kneecap has dislocated repeatedly or remains unstable
  • The kneecap clearly shifts off its track when the knee moves
  • The dislocation damaged the knee more seriously, for example the cartilage

Not sure which stage you are in? The examination decides. Book a consultation

How the procedure goes

From booking to going home

Surgery stabilizes the kneecap again. The usual approach is reconstruction of the ligament that holds the kneecap from the inner side: the damaged ligament is replaced with a graft from one of your own tendons. When the cause is the shape or alignment of the bones, correcting them may be needed as well. What is suitable for your knee is decided by Prof. Hart after the examination.

  1. Booking

    Online or by phone. A referral from a general practitioner is not required.

    online or phone

  2. Consultation and examination

    Prof. Hart examines the knee and checks how the kneecap moves as you bend and straighten it. An X-ray, magnetic resonance imaging or CT shows the alignment of the bones, the ligaments and any loose fragments.

    diagnosis and treatment plan

  3. Procedure

    The extent of the surgery depends on the cause of the instability.

    within a week of the consultation

  4. Home and exercises

    You go home as soon as everything is in order. Targeted physiotherapy is decisive for restoring strength and stability. Do not drive until the doctor allows it; someone must take you home.

    follow-up and physiotherapy

Recovery and physiotherapy

Strength and stability return gradually

With or without surgery, regular exercise decides the result. When needed, we follow up with physiotherapy right at the clinic.

Room in the short-stay ward at HR Clinic

  1. Without surgery: 1 to 3 months

    After a first dislocation, the goal is to be back to everyday activities within 1 to 3 months. Full recovery can take several months, but many people can walk right after treatment.

  2. After ligament reconstruction: around 4 months

    That is how long recovery after ligament reconstruction usually takes.

  3. Sport only at full strength

    Return to sport once the knee has regained its usual strength. The doctor or physiotherapist will tell you when that is. Until then, do not twist the knee.

Prof. MUDr. Radek Hart, Ph.D., FRCS, MHA

Who operates

Prof. MUDr. Radek Hart, Ph.D., FRCS, MHA

Orthopedic and trauma surgeon of the musculoskeletal system, head physician of HR Clinic. He stabilizes a repeatedly dislocating kneecap by reconstructing the ligament that keeps it on the correct track. He sees patients in Znojmo and in Vienna; after a consultation in Vienna, the procedure can be done in Znojmo.

More about Prof. Hart Specialist website ortho-hart.at

Price We will tell you the price of the procedure at the consultation, based on the findings and the extent of the procedure.

Frequently asked questions

What patients ask most often

Related

Torn anterior cruciate ligament Damaged cartilage and meniscus Knee arthroscopy and meniscus How it works at HR Clinic
Does a dislocated kneecap have to be operated on?

After a first dislocation, usually not; treatment starts with exercises and a brace. Surgery comes into consideration when the kneecap dislocates again, when the risk of recurrence is high from the start, or when the dislocation damaged the knee more seriously.

The kneecap went back by itself. Should I see a doctor?

Yes. Even if the kneecap returns to its place on its own, the knee needs to be examined, usually including an X-ray. A dislocation can damage the cartilage or free a small fragment.

Is there a risk of arthritis after a dislocation?

A dislocation often damages the cartilage on the underside of the kneecap and at the end of the thigh bone, which can lead to pain and later to arthritis. Repeated dislocations raise the risk of cartilage damage, which is one reason surgery is considered.

How often does the kneecap dislocate again after surgery?

Results of the surgery are generally very good: according to medical reviews, the kneecap dislocates again in fewer than 1 in 10 patients operated on. Thorough rehabilitation also contributes a great deal to the result.

Do I need a referral from a general practitioner?

No. You can simply book online or by phone.

Booking

Book an orthopedic consultation

Online or by phone, at the clinic in Znojmo. A referral from a general practitioner is not required.

Book a consultation
Book a consultation