A knee dislocation can occur after a violent or brutal shock. It requires rapid intervention in order to avoid nervous or vascular complications. What are the symptoms ? What treatments to cure a knee dislocation?
A knee dislocation occurs when the bones of the knee joint are forced out of their normal position, resulting in abnormal movement of the joint. Knee dislocation can occur following a trauma, usually during an accident or a fall. Once a knee dislocation is suspected, it is important to consult immediately a healthcare professional. Medical monitoring is essential for appropriate management. What is a knee dislocation? What are symptoms ? How much time to heal a dislocated knee? What to do ?
Definition: what is a knee dislocation?
A knee dislocation can be reduced to complete dislocation of the joint. It almost always leads to ligament tears (cruciate ligaments and/or peripheral ligament of the knee) but can also cause damage to the popliteal vessels or the sciatic nerve.
What are the symptoms of a knee dislocation?
Dislocation causes:
- a visible knee deformity,
- a impotence total or subtotal (the patient cannot perform certain movements such as flexion or extension),
- of the pains which must be treated by rapid management including the reduction of the dislocation (“repositioning of the articular parts”).
“The patient can partial or total loss of sensitivity of his leg or this one may also no longer have its usual coloring in the event of arterial or venous lesion”, continues Dr. André Ferreira, orthopedic surgeon. Faced with a dislocated knee, you must immediately contact a emergency service or to a specialist (orthopedic surgeon) who will take the necessary measures for the treatment.
The treatment of a dislocation of the knee begins, after the clinical assessment and the basic complementary examinations (radiography at least) by its reduction which allows the relief of the pain. It’s a procedure performed most often under general anesthesia. In addition, medical treatment combines painkillers and/or anti-inflammatories (in the absence of any particular contraindication). “In the event of very severe pain, the specialist can make use of stronger molecules (morphine for example) and in children, relaxant gases can be used” suggests Dr. Ferreira. Then a immobility of the joint is necessary to allow the ligament lesions to heal (by plaster, resin or splint) for a period of 6 weeks on average.
► With or without surgery, rehabilitation is essential ; it is started during hospitalization and can then be continued in a rehabilitation center or at the physiotherapist’s office.
Most dislocations are the result of a violent shock
How long does it take to heal from a dislocated knee?
It is at least equal to the immobilization time (6 weeks); in case of surgery, it may be longer (3 to 6 months). The resumption of sports cannot be considered only after 3 or 4 months even more in the case of ligament reconstruction.
It is most often placed by observing the appearance of the knee sinceit deforms and swells. “In case of anterior dislocation, the tibia protrudes forward; in case of medial dislocation, the deformity takes on the appearance of a bayonet” details our interlocutor. “It may also happen that the deformation is not visible, due to the extent of the swelling.” Finally, in some cases, the dislocation has already been reduced (by the patient or by a worker at the site of the accident) even before the consultation with the surgeon. A complete clinical examination of the knee, in particular the ligament, is essential. Disappearance of peripheral pulses, loss of sensitivity and/or motor skills of the leg should raise suspicion of arterial or nerve damage. Arteriography or angio-MRI are then requested to confirm or not the existence of a vascular lesion. MRI of the knee allows to complete the assessment to know the ligament lesions.
When to consider surgery for a dislocated knee?
In cases of vascular lesionssurgical repair is generally necessary (suture, bypass, etc.). For ligament injuries, an intervention can be envisaged even if it is not systematic. Ideally it takes place very soon after the trauma but can be postponed if necessary. It consists of a ligament plasty with the patient’s ligaments (graft) and sometimes synthetic reinforcements.
What are the causes of a dislocated knee?
“Most of the dislocations are consecutive to a violent shock (traffic accident, sports accident) but they can also occur after a more banal trauma such as twisting of the knee in walking with the leg stuck in a hole“, explains Dr. André Ferreira, orthopedic surgeon. We distinguish different types of dislocation depending on the direction in which the tibia moves relative to the femur; the most frequent is the anterior dislocation but it can also be posterior or latero-medial.
Thanks to Dr André Ferreira, orthopedic surgeon at the Clinique du Parc in Lyon.