Cruciate Ligament Injury; Causes, Symptoms, and Treatment
The anterior cruciate ligament (ACL) is one of the ligaments located inside the knee - it connects the femur bone to the front of the tibia bone. An anterior cruciate ligament injury is a partial or complete tear or separation of the cruciate ligament in the knee, and it is a common injury, especially among athletes.
What Is the Anterior Cruciate Ligament (ACL)?
The knee consists of bones, ligaments, tendons, and cartilage. The anterior cruciate ligament (ACL), which is located in the front part of the center of the knee, connects the femur bone and the tibia bone, and its main function is to stop forward movement, and it prevents the femur and tibia bones from moving out of their place.
There are also four basic ligaments located in the knee, which are:
- The anterior cruciate ligament ACL.
- The medial collateral ligament MCL.
- The lateral collateral ligament LCL.
- The posterior cruciate ligament PCL.
The anterior cruciate ligament passes in front of the posterior cruciate ligament (PCL). When these ligaments stretch without tearing, this condition is called a sprain.
Types of Anterior Cruciate Ligament Tears
When you sustain a cruciate ligament injury, your healthcare provider may classify the injury into grades from one to three, with grade three being the most severe. It can be classified as follows:
- Grade one: stretching of the cruciate ligament, but it still performs its function of stabilizing the knee joint.
- Grade two: stretching of the cruciate ligament, and its loosening is a partial tear.
- Grade three: tearing of the cruciate ligament, and its cutting into two pieces, and this is a very serious injury.
Anterior cruciate ligament tears are often accompanied by injuries to the collateral ligaments, the joint capsule, or the meniscus of the knee.
Causes of Anterior Cruciate Ligament Injury
Most anterior cruciate ligament injuries occur during sports, especially soccer, basketball, and skiing. However, women are more susceptible to anterior cruciate ligament injury than men.
An anterior cruciate ligament injury may occur for several reasons, including:
- Being exposed to a severe blow to the side of the knee.
- Twisting the knee, especially when the foot is planted on the ground.
- Landing from a jump and twisting the knee in the opposite direction.
- Changing direction quickly when running or walking.
- Stopping suddenly when running.
- Extending the knee joint.
Symptoms of Cruciate Ligament Injury
The common symptoms of an anterior cruciate ligament tear include the following:
- A popping sound at the time of the injury.
- Pain, especially when trying to put pressure on the injured leg.
- Swelling of the knee within an hour or two of the injury.
- Difficulty continuing to practice sports.
- Difficulty walking on the injured foot.
- Instability of the knee.
In some less severe cases of tearing, these symptoms may be mild.
But if the anterior cruciate ligament tears completely, there will be obvious instability in the knee, leading to a feeling of sudden shifting or twisting. People will not be able to:
- Jump and land on the knee.
- Accelerate and then change directions.
- Lose complete control over the knee.
First Aid for Cruciate Ligament Injuries
If you think you have an anterior cruciate ligament injury, do not practice sports or any other activities until you are examined by a specialist, but until that time there are some first aid measures that may help.
First aid for an anterior cruciate ligament injury includes the following:
- Do not move your knee if you have sustained a serious injury.
- Raise the leg above the level of the heart.
- Apply ice to the knee.
- Do not return to playing or other activities until you are treated.
- Use a splint to keep the knee straight until you see the doctor.
- Use crutches to walk until the swelling and pain improve.
Treatment of Anterior Cruciate Ligament Injury
The treatment you receive depends on the extent of the severity of the damage and how active you normally are. The initial treatment will be to control the pain and swelling. Treatments may include physical therapy, medications, and sometimes surgery.
Medications
Over-the-counter painkillers can be taken, such as paracetamol or ibuprofen, if you feel pain. The doctor may prescribe stronger painkillers if your knee is very painful.
In addition to relieving pain, non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen may help in reducing inflammation and swelling.
Physical Therapy
Your physical therapist will assess your knee and then plan a rehabilitation exercise program suitable for your individual needs. The physical therapy program will be designed to give you the best chance to return to your usual activity more quickly.
Be regular in doing the exercises because this is a very important part of your recovery program, and the goal of physical therapy lies in helping the knee restore its full range of motion, its strength and stability, and to return to working normally.
Surgery
If the knee is unstable and you lose control over it when practicing sports or sometimes this happens just from walking, then surgery may be the best option to repair your injury if you practice sports a lot or are in a job that requires physical effort. For example, surgery becomes a necessity in the following cases:
- Practicing sports that involve a lot of twisting and turning - such as soccer or basketball.
- Working in the military, or being a firefighter, police officer, or working in the field of construction.
Often your doctor will not recommend performing a surgical operation immediately after the injury, but it is usually best to wait at least a week or two to allow the swelling of the knee to subside.
Also, returning to full activity after the surgery may take between 6 to 12 months, and you will undergo an intensive and long period of physical therapy after the operation.
Simple cruciate ligament tears or sprains often heal with non-surgical treatment such as physical therapy. But if you suffer from a serious knee injury, contact the specialist doctor immediately to advise on the best suitable treatment to avoid worsening of the symptoms.

