A dislocation occurs when the bones that form a joint get out of place.
A knee dislocation, more specifically, is when the bones of the leg (the tibia and fibula) are displaced in relation to the bone in the thigh (femur).
One important thing to know is that the bones of the knee are held together by strong bands of tissues called ligaments, so it is a fairly stable joint that isn't very prone to dislocations. What this means is that to have a dislocated knee, a lot of force or pressure must have been suddenly applied to the knee joint to push the bones out of place.
The different strong ligaments in the knee stabilize it and keep it in a balanced position. When a knee dislocation occurs, these ligaments tear. In some injuries, the kneecap and its ligaments are also disrupted.
The question that may come to mind is:
What causes a dislocated knee? If the knee is a fairly stable joint, what type of forces or events are capable of tearing the strong ligaments apart, dislocating the joint? Well, here are the common causes of a dislocated knee.
What Can Cause a Dislocated Knee?
Knee dislocations are very rare but they can happen after a major trauma that provides enough force to make the ligaments give way. Here are some events that can cause it:
If a car gets out of control and slams into objects, banging the knee against a hard surface like a dashboard or seat frame can be very impactful on the knee. The force of the blow can be strong enough to dislocate the knee.
This is a far less common cause of a dislocated knee when compared to motor vehicle accidents. However, when playing sports, colliding with another player or sudden twisting movements can create a great force that can pull the bones in the joint apart.
It may happen to skiers and runners who lose their control and fall on bent knees with great force. The impact can be immediate and lead to a knee dislocation.
Now that we have explored three possible causes of this condition, let's go further to discuss its symptoms. It is time to know what things to look out for that suggest that the bones in a knee have moved out of their normal position.
Symptoms of Knee Dislocation
Here are common symptoms that a person with a dislocated knee may observe:
- Severe knee pain
- Knee swelling
- Being unable to walk
- Knee deformity- the normal straight line of the leg will seem a bit crooked.
- Inability to move or straighten the leg
It is important to note that in some cases, a dislocated knee could go back into place (relocate) on its own before the person even reports to a clinic. In such a case, the knee could still be swollen and painful even though the deformity has self-corrected.
One very serious problem that may arise from this condition is when the dislocation affects surrounding blood vessels, leading to a disruption of blood supply to the leg. In this case, a person may experience symptoms like the absence of a pulse below the knee or loss of feeling or movement below the knee.
How Is It Diagnosed?
You should visit your doctor immediately if you think you have a dislocated knee from trauma. You can't confirm this on your own and will need to be physically examined by a doctor.
Also, if you feel there was a dislocation that has resolved on its own, you should still go to the doctor immediately for a proper assessment.
Your doctor will ask you several questions relating to how the injury happened, the changes you have observed in your knee, your ability to walk, and what you might have done to treat it on your own before presenting at the hospital.
The doctor will note down whether or not your knee is swollen or if you can move it or not. The range of motion of your knee will also be examined.
He/she will also make a note of what your skin looks and feels like below the knee all the way to your foot. This is because this condition may cause damage to nerves or blood vessels which may change the color and temperature of your skin. This could affect blood flow or your sense of touch below the knee.
X-rays are taken to look at the position of each bone in relation to the others. Remember that the knee joint is made up four bones- the thigh bone, kneecap and two leg bones (tibia and fibula). If the knee is dislocated, the position of the bones will be able to tell this easily.
Apart from this, an X-ray is useful in checking that there is no related fracture of any bones that make up the joint. Doctors would usually request for both a front and side view Xrays of the knee.
An MRI is good in helping doctors get a good view of internal soft tissues of many parts of the body.
In this case, it will show whether any of the ligaments or soft tissues in the knee have been damaged.
Also, if surgery is required, it can also help a surgeon prepare for a surgical knee procedure by providing a detailed analysis of each bone and ligament, their dimensions and position. These details are necessary if there's a need to fix torn structures inside the knee.
Will I Need Surgery?
Well, the answer is: it depends.
Many variables come into play, but the decision can only be made after a proper history documentation, physical examination, and investigation by a doctor.
If the dislocation didn't seem to affect your ability to use your knee sufficiently well enough, and if you don't plan to use the knee for serious sporting activities, your doctor may opt for a conservative form of treatment. Let's discuss the non-operative treatment options.
Closed reduction of the dislocation:
If the damage to your knee isn’t too severe, your doctor may try to pop your bone back into place by pulling, pressing and moving your leg in certain ways. This will be done with some pain relief, so you shouldn't be afraid.
After your bone is back in the joint, you’ll likely need to wear a splint for a few weeks to allow your knee to heal without much joint movement or weight bearing.
Non-steroidal anti-inflammatory medications, such as ibuprofen or naproxen may be recommended or prescribed to address both the pain and inflammation. Other painkillers like acetaminophen and opioids may be prescribed, depending on how severe the pain is.
Devices like crutches, braces, and walkers may be recommended to reduce pressure on the knee joint and allow healing take place.
An array of stretches and exercise may be prescribed for a predetermined period after treatment in order to strengthen the structures in the knee joint. Also, it helps to prevent the knee from getting stiff or immobile. If there is no movement across a joint for a long time, the structures around the joint could get fixed and restrict mobility.
Sometimes, the examining doctor may recommend a surgery based on X-ray or MRI findings. Common surgeries for dislocated knees are:
This sort of surgery involves inserting a small camera into the knee joint and using a projected image to determine what damage has been caused in the knee by dislocation.
This type of procedure will typically be undertaken after arthroscopic surgery has already been performed. It may involve removing or repairing damaged cartilage, relocating a severely dislocated kneecap or repairing damaged ligaments and tendons.
Surgical procedures will typically be followed by physiotherapy sessions to strengthen the knee.
What Is The Recovery Time For Dislocated Knees
The answer to this question depends on how bad the dislocation was and what form of treatment was applied.
For dislocations that were not operated, doctors could apply a knee brace that will be in place for about two weeks, after which recovery then depends on how bad the injury was and how well the physical therapy is done.
For operated dislocations, there's sometimes need to wait for 6-8 weeks before serious movements or weight bearing can be done across that knee joint. This is usually accompanied by physiotherapy.
Is There A Way To Prevent Knee Dislocation?
These are steps you can take to keep yourself from dislocating your knee joint:
- Try to stay safe and avoid major accidents, especially at work.
- Wear knee guards during sports or recreational activities, such as roller-skating or soccer.
- Stretch before and after physical exercise, sports, or recreational activities to warm up your muscles.
- Use the correct techniques or positions during activities so that you do not strain your muscles.
- Avoid risky activities such as skiing, motorcycle riding or jumping from high places. If any of this is done take instructions from an expert to avoid such risks
In general, even though this is a very serious injury, a good recovery is possible. You should also know that the injured knee may not regain its previous capacity to absorb stresses.
It is not uncommon for doctors to recommend some types of supportive wraps or devices to protect the knee and to reduce stresses on it, especially during activities like skiing or playing football. Some knee dislocations cause so much damage that some doctors will suggest that certain activities are avoided altogether.
You should, therefore, focus on preventive steps you can take to protect yourself from getting a dislocated knee. Also, if you think you have hurt your knee, you should get it examined at a hospital as fast as you possibly can so that an appropriate treatment can be commenced on time.