A rare but serious orthopedic emergency requiring rapid and appropriate management.
A dislocated knee is a rare but potentially serious injury. It involves a complete loss of contact between the femur and tibia, often associated with major ligament damage and sometimes with vascular or nerve damage. This condition usually occurs following a violent trauma, such as a road accident or a significant sports impact.
In the case of a dislocated knee, rapid diagnosis and treatment are essential. Treatment depends on the severity of associated injuries and relies on a comprehensive approach, ranging from emergency reduction to ligament reconstruction.
What is a dislocated knee?
A knee dislocation corresponds to a complete displacement of the joint, with rupture of the stabilizing structures. Unlike a sprain, even a severe one, this is a total disorganization of the joint.
In most cases, several ligaments are affected:
- THE anterior cruciate ligament (LCA)
- the posterior cruciate ligament (PCL)
- the lateral ligaments (internal and external)
This combination of injuries makes the knee extremely unstable. Sometimes, the dislocation reduces spontaneously before arrival at the emergency room, which can complicate diagnosis.
An emergency that should never be underestimated
The severity of a knee dislocation is not solely due to ligament damage. It lies primarily in the risk of associated injuries, particularly vascular ones.
The popliteal artery, located at the back of the knee, can be compressed or damaged during the injury. This can lead to reduced blood flow to the leg, with a risk of serious complications if not treated promptly.
Similarly, the fibular nerve can be affected, causing sensory disturbances or partial paralysis of the foot.
That is why any suspicion of a knee dislocation should be considered as a absolute medical emergency.
What are the symptoms?
The symptoms of a dislocated knee are usually pronounced and immediate. The patient experiences intense pain, often accompanied by a visible deformity of the joint.
The knee may appear abnormally positioned, with rapid swelling. Movement is very painful, or even impossible. In some cases, the deformity disappears spontaneously if the dislocation reduces on its own, but pain and instability persist.
Certain signs should be of particular concern:
- inability to put foot on the ground
- feeling of major instability
- numbness or loss of sensation
- cold or pale feet (sign of vascular damage)
Diagnosis: a key step
The diagnosis is based first on the clinical examination. The doctor looks for overall instability of the knee and checks the vascular and neurological status.
Imaging examinations are routinely performed:
- X-rays to confirm the dislocation or check the reduction
- MRI to analyze ligament and cartilage lesions
- CT scan or Doppler ultrasound in case of suspected vascular lesion
The goal is to establish a complete assessment of the lesions in order to adapt the treatment.
Emergency treatment
The first step in the treatment is the reduction of the dislocation, That is to say, to put the joint back in place. This procedure is performed as an emergency, under anesthesia if necessary.
Once the reduction has been carried out, the knee is immobilized and further examinations are performed to assess the damage.
If vascular damage is suspected, urgent surgery may be necessary to restore blood flow.
Treatment of ligament injuries
After the emergency phase, ligament treatment becomes the priority. In most cases, several ligaments are torn, requiring surgical reconstruction.
The treatment may be:
- delayed, after an initial recovery phase
- carried out in one or more operational stages
- adapted according to the condition of the tissues and the patient
The surgery involves reconstructing the ligaments using tendon grafts, in order to restore stability to the knee.
The role of rehabilitation
There rehabilitation This is an essential step, regardless of the treatment. It begins as soon as possible and continues for several months.
Its aim is to:
- restore joint mobility
- strengthen stabilizer muscles
- improve coordination and balance
- to accompany the resumption of walking
Recovery is often a long process, requiring patience and consistency.
What results can you expect ?
A dislocated knee is a serious injury, and a full recovery is not always guaranteed. However, with proper treatment, it is possible to regain satisfactory function.
The results depend on several factors:
- severity of initial injuries
- speed of response
- quality of surgery and rehabilitation
Some patients are able to resume sporting activity, while others continue to experience discomfort or limitations.
Possible complications
Even when properly treated, a dislocated knee can lead to long-term complications.
Among the most frequent:
- joint stiffness
- persistent instability
- chronic pain
- early osteoarthritis
These risks justify regular medical monitoring.
Essential specialized care
Knee dislocation requires specialized care, often in an experienced center. Diagnosis, emergency management, surgery, and rehabilitation must be coordinated to optimize outcomes.
Key takeaways
Knee dislocation is a rare but serious orthopedic emergency.
- It often involves several ligaments
- It can be accompanied by vascular or nerve damage.
- It requires an urgent reduction
- The treatment is often surgical.
- Rehabilitation is long but essential
Prompt and appropriate care helps to limit complications and improve the chances of recovery.
