Pediatric Orthopedic Surgeons treating a torn and Sprained Knee


The knee ligaments connect the leg bones and support the knee joint. A knee sprain occurs when a person tears or overstretches a ligament.

If your child needs surgery or casting, our Fracture Care Clinic opens every day and you do not need an appointment. Surgery rooms get scheduled every morning, so your child receives the care and attention they need right away.

Sprained Knee

The knee ligaments connect the leg bones and support the knee joint. A knee sprain occurs when a person tears or overstretches a ligament in the leg. The ligaments in the human knee are bands of tough, elastic connective tissue that connect the femur to the bones of the lower leg. In addition, ligaments also provide support and help limit joint movement. This article explains the types of ligament sprains that affect the knee, their causes, treatment options, and when you should see a doctor.

There are four primary ligaments in the knee, and each one is crucial to maintaining stability and allowing for a complete range of motion. The two collateral ligaments govern the sideways movement of the knee, whereas the two cruciate ligaments control the knee’s back-and-forth motion. Depending on which ligament has been damaged, a person may be experiencing one of the following types of knee sprains:

Anterior Cruciate Ligament

Medical professionals commonly refer to this ligament as the ACL. Located inside the knee joint. Two cruciate ligaments control the fore-and-aft movement of the knee. Together they form an “X” shape. The anterior cruciate ligament in older children will get damaged in may sports.

Posterior Cruciate Ligament

The posterior cruciate ligament (PCL) is the anterior cruciate ligament equivalent in the back. The tibia, or shin bone, can only travel rearward under the supervision of the PCL.

Medial Collateral Ligament

The ligament that provides stability to the inside knee is known as the MCL. The lateral ligaments are on the sides of the knee. Within the knee is the medial collateral ligament.

Lateral Collateral Ligament

This is a knee ligament that supports the knee’s outer surface. The lateral collateral ligament (LCL) is on the outside of the knee.

Classification System

Any damage to a knee ligament is classified as a sprain by medical professionals, who grade the severity of the sprain using the following scale:

  • Grade I: A person overstretches the ligaments in a modest grade 1 sprain, but the ligaments are still able to stabilize the knee joint.
  • Grade II: A person with a moderate grade II sprain will have evidence of a partial ligament tear. When someone puts weight on the afflicted leg because the ligament is loose, the knee may feel unstable and uncomfortable.
  • Grade III: The most serious kind of sprain is a grade III. The ligament has completely torn here. It has a significant loss of function and range of motion as well as severe instability. The leg may be difficult or impossible to bear weight on due to excessive swelling and bruising.


Depending on whatever ligament a person has strained in their knee, the associated symptoms may change. Also, the knee may snap and buckle as a result of damage to one of the collateral ligaments, which can hurt and swell. A popping sound is frequently audible when a cruciate ligament is torn. As the individual tries to stand on the leg, it can potentially give way. Swelling may also happen, often within 24-36 hours. According to our doctors and surgeons, the interior of the knee will hurt if MCL damage develops. If the LCL is injured, the pain is on the outside of the knee. Multiple knee ligament sprains, sometimes known as the “unhappy trifecta,” can accompany ACL damage.

Causes of each Type of Sprain 

When the knee undergoes a forceful muscular contraction or makes direct contact with anything, it sprains. For instance, these scenarios might occur when a runner changes direction too rapidly or while participating in sports.

Cruciate Ligaments

The ACL is the knee ligament that sustains injuries the most frequently. When a person abruptly changes directions, usually while moving quickly, the ACL may be injured. Additionally, it can happen when the knee receives a blunt force, such as during a tackle in football. In instances where the front of the knee is directly contacted, such as in football, PCL injuries frequently occur.

Collateral Ligaments

These ligament injuries usually occur when a force pushes the knee sideways. When there is a direct blow to the outside of the knee, it can result in an MCL ligament injury. Also, MCL injuries can also occur with improper landings that puts a “valgus” force on the knee. Furthermore, a blow to the inside of the knee can push the knee outward and damage the LCL. Lateral collateral ligament injuries are common in contact sports.

Sprained Knee Treatment

Depending on the extent of your injury and the specific area of your knee that was hurt, your doctor will advise a course of therapy.

Pain medication

Our doctor may recommend over-the-counter pain relievers such as acetaminophen.


Avoid doing anything that puts too much strain on your child’s knee and puts him or her in danger of further injuring it. Playing sports should be avoided until the knee is healed.

While sitting or sleeping, you can also prop your leg up on pillows to get it higher than your heart to help reduce the swelling.

Ice for a knee sprain

In order to minimize swelling, apply an ice pack to the knee for 20 minutes every few hours (but check with a our doctor first, especially if you have diabetes). The ice might also halt any internal bleeding and reduce pain.


With caution, avoid wrapping your child’s knee to tightly with an elastic bandage, as this might prevent blood flow and cause additional swelling. Loosen the bandage if it causes swelling in the lower leg, knees to go numb, or the wrap causes more pain.

Immobilization of a knee sprain

Our doctor might suggest that you immobilize or stop moving the knee for a short while. This gives your body time to recover naturally and enables any swelling and soreness to go down. Our doctor might recommend wearing a brace over your knee to support and protect the joint as it recovers. Additionally, most braces have moveable pieces and extend above and below the knee; their main function is to allow you to walk and gently flex your knee while wearing them. You can’t move your knee from side to side or overextend the joint in any way while wearing the brace.


If your symptoms include swelling, warmth, or redness, your doctor may recommend a procedure called a joint aspiration to remove fluid from the joint. During a joint puncture, doctors first inject a small amount of a local anesthetic to numb the skin, then insert the needle into the fluid-filled joint space. Your doctor will remove the fluid through the needle. This often helps relieve knee pain.

Knee sprain workouts and physical therapy

Depending on the severity of your injury and where you are in your rehabilitation, a doctor or physical therapist may advise the following exercises:

  • leg lifts
  • thigh strengthening
  • bending your knees
  • raising up on your toes
  • thigh and calf stretches
  • using the leg press and hamstring curl machines for weight training

Non-Surgical Treatments for a Knee Sprain

The majority of knee sprains are treatable with non-surgical methods that focus on restoring the knee’s full strength.

Physical therapy. After initial treatment to reduce pain, knee sprains are commonly treated with physical therapy. Physical therapy combines exercises to strengthen the knee with activities to increase flexibility and restore knee flexibility. His two main components of physical therapy are:

Weight training: The physical therapist will have the patient lift small amounts of weight in repetitive sets. This exercise may include resistance bands, weighted braces, or exercise equipment that affect the knee joint. Over time, increase the number of repetitions and the weight lifted in a controlled and progressive manner.

Stretching for flexibility. A therapist may want to periodically measure a particular athlete’s range of motion and offer stretches to increase the range of motion. A return to a fully normal range of motion and flexibility usually indicates that the athlete is almost ready to return to exercise training.

The length and intensity of your physical therapy program will depend on several factors, including your age, medical history, athleticism, and the severity of your knee sprain.

Surgery for a Knee Sprain

Severe knee sprains may require surgery to repair damaged ligaments. Surgery is usually only recommended if the knee sprain is Grade III (complete ligament tear). Surgical repair of knee ligaments is usually performed arthroscopically, which is a minimally invasive approach. In arthroscopic surgery, a small incision (usually less than 1.2 cm his) is made in front or behind the knee and a miniature camera is inserted into the leg. A camera evaluates the degree of a knee injury. Once this is done, a small tool is also inserted into the knee to remove or repair damaged tissue.

Call 214-556-0590 to make an appointment.

Comprehensive services for children from birth through adolescence at four convenient locations: Arlington, Dallas, Frisco and McKinney.