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> Sprain Knee
Knee sprain
It is a very frequent knee trauma
Knee sprain is an injury which occurs to ligaments, that allow the stabilization of the femur with the tibia and patella, caused by being over stretched beyond their normal capacity and possibly torn.
Causes
- Sport injuries
- Traffic accident
- Slides and brutal unwanted motions
- Twisting of the knee when the foot is in a stopped position.
Injuries
- It can be minor (simple tear) or severe (complete tear of the ligaments).
- The sprain can cause lesions of the knee.
- The sprain can cause a tear of the menisci.
- The sprain can cause a fracture.
- The patella can be traumatized.
- The knee sprain can compromize very much the stability of the knee. (chronic sprains, recurrent sprains).
- The sprain can cause risks of future arthrosis.
Knee ligaments
The knee is sustained by :
- Lateral ligaments located on the side of the knee. There are the internal and external ligaments.
- Important ligament located in the center of the joint (the cruciate). There are the posterior and anterior cruciate ligaments.
The lateral ligaments protects the lateral side from an inside bending force (preventing the knee from being bent open or bent inside by an outside force).
The cruciate ligament prevents the tibia from being pushed too far anterior relative to the femur and posterior displacement of the tibia relative to the femur. The more critical is the ACL.
The tear of a cruciate ligament is less frequent than the tear of a lateral ligament. Hence it is important to be very cautious when diagnosing a knee sprain.
The mechanisms of the knee sprain
- After the foot get stuck to the ground, the leg slightly bent rotates around the axis of the foot. The body weight finishes the job, and the ligament get torn. It can be a partial or total tear. Most of the time it is partial.
- The internal lateral ligament get bruised more frequently (90% of the cases).
- All kind of lesions shall be considered (cruciate ligaments, menisci, cartilages, bones)
- Sport injuries are the most frequent (skiing, football, rugby, hand ball, fighting sports etc.)
The consequences of knee sprains
- The stability of the knee can be compromized in the future if the injury was not properly treated (surgery, medications)
- Pain and chronic instability
- Meniscus lesion can occur later on
- The risks of osteoarthrosis are greater
Symptoms
- severe pain
- Swelling of the knee (Joint blood effusion called hemarthrosis).Impossibilty of walking or putting the foot on the ground. But usually the sprain does not prevent to use the injured limb.
- All these symptoms can occur jointly or separately.
What to do in case of a knee sprain ?
- When the knee is painful, consider until proven the contrary that it is a sprain.
- Apply ice immediately if possible (in a plastic bag) for about 30 minutes, and do not hesitate to remove the bag if the pain is unbearable. You can start again later.
- Go home and try not to use the injured limb. A cab is appropriate.
- At home, apply ice on the sprain and elevate your feet in the air.
- Schedule rapidly an appointment to see a knee physician or specialist that will prescibe medications or further examinations (MRI, Xraysetc...) and deliver a diagnosis.
The appointment
The specialist will perform specific manoeuvers to look for abnormal motions that would evidence a severe sprain and a resulting tear of the cruciate ligament. He will perform or have you do a Xray exam to look for bone lesions. A MRI can be prescribed if the physician suspects a cruciate or meniscus lesion.
The treatment
The treatment will always be medical first, and prescribed right after the sprain. The surgical treatment is exceptionnally an emergency (except in cases of severe ligament injury resulting in a joint dislocation, or in case of collateral fracture that needs an emergency surgery or in case of a bent knee, stuck by a meniscus sprain).
Medical treatment
- Antalgics and anti-inflammatories to limit and stop the pain
- Immobilization with a knee brace for a 1 to 5 weeks period depending on the severity of the injury
- Daily icing to lessen the pain and the hematoma
- Cautious walk and temporary break in the practice of sport.
- Immediate kinesitherapy sessions to prevent joint stiffness and amyotrophy (decreasing of muscular mass).
Surgical treatment
- Aseptic technics
- By a specialized knee surgeon
- Ligament repair procedure is never an emergency
- Ligamentoplasty by arthroscopy (modern technics) in case of a tear of the cruciate ligament
- Excellent results when performed by an experienced surgeon
Choice of the treatment
- Only your specialized therapist can advise you as to choose between the medical and surgical treatment.
- The medical treatment is always the one to be favoured primarily.
- Minor sprains of the lateral ligaments are medically treated.
- Cruciate ligament injuries are often treated by surgery but not all the time. If the patient is under the age of 45, that he practices a lot of sport and wants to start again as soon as possible, that the knee is unstable in the every day routine.
Post-operative
- There are no complications if the treatment has been followed to the letter.
- There are still too many unstable knees in result of ill treated minor sprains or non diagnosed cruciate ligament tears.
Conclusion
- Knee sprain is a very frequent injury
- A professional advice or opinion in a specialized environment is always necessary.
- In case of ill treated or non diagnosed sprain, there is a risk of functional disabilities and pain.
- There is a risk of wearing-out of the joint and osteoarthrosis
- Excellent results if the treatment is well adapted.
