Knee sprains

Many patients consult in physiotherapy for a knee sprain. This injury occurs during false movements where the knee undergoes torsion or excessive movement that causes structural damages.

The structures

The knee is composed of the femur, the patella, the tibia and the fibula. Ligaments are the fibrous structures that connect one bone to another, like the femur and the tibia, and are responsible for the stability of the joint. In the knee, we find the anterior and posterior cruciate ligaments (ACL, PCL) and the internal and external collateral ligaments (ICL, ECL). The menisci are the two fibrocartilaginous structures between the femur and tibia that reduce friction and dissipate the load.

What is a sprained knee?
A sprained knee occurs when there is either a stretch (grade 1), a partial tear (grade 2) or a complete tear (grade 3) of one or more ligaments. Ligament injuries often come with meniscus affections, and in grade 3 sprains, bone tearing is possible.

Signs and symptoms
Knee sprain initially may take the form of pain, edema, bruising and heat. It also includes a feeling of instability of the knee, expressed by weaknesses, a lack of control and a disturbed balance. During the assessment, we often note pain on palpation and disturbance of joint stability, strength, mobility, proprioception and load-bearing capacity.

Treatment
Your physiotherapist and doctor can perform clinical tests to detect the injury. They can guide you in its care. Magnetic resonance imaging (MRI) is used to determine the severity of the damage.
The treatment will vary according to the severity of the sprain. In severe cases, surgery may be indicated to reattach the torn ligament. The medication will improve the condition with regard to pain and inflammation. An orthosis may also be recommended to help stabilize the joint in activities.
In physiotherapy, the objectives are to ensure optimal healing, adequate mobility and strength and the absence of complications. Therefore, manual therapy, mobilizations, tapping, electrotherapy, cryotherapy and thermotherapy, as well as exercises will improve the condition. It is important to have optimal strength and stabilization to compensate for the lack of stability. Your physiotherapist will also guide you back to sport or work.

Evolution
The knee sprain can heal in 4 to 6 weeks, but can sometimes last up to 3 months depending on certain factors: severity, treatment received and history of injury, among others.
It is strongly recommended to consult a physiotherapist within the first 72 hours to optimize healing and obtain appropriate care.