During a soccer game, especially after a sedentary period, a player may try to discard the opponent and feel a painful pop or snap in the knee.

Knee snapping, of course, is not an experience limited to amateur soccer players. Still, it is possible for anyone who plays sports requiring fast movements and sudden changes of direction, such as beach volleyball, basketball, or tennis. 

A popping knee causes pain and swelling. Consulting with an orthopedist is essential to assess whether it is a mild injury requiring rest and ice or immediate treatment.

What does a pop in the knee mean?

A pop feels like a kind of painful “click” inside the knee following a movement that involves a knee twist.

This often means that there has been a tear or injury in:

  • Anterior cruciate ligament (ACL);
  • Medial collateral ligament (MCL);
  • Menisci;
  • Cartilage;
  • All of the above.

These are common sports injuries, not just in amateur or professional soccer. Excessive training, muscular stress, and insufficiently toned leg muscles can cause injuries to the knee’s menisci, ligaments, and cartilage.

Knee injuries and their symptoms

A knee ligament injury (sprain) can occur when one or more ligaments that connect the femur to the tibia and keep the knee stable are torn.

This kind of injury can occur in sports like soccer due to a sudden knee twist with one foot planted on the ground or from high-impact contact with another player. In other sports, however, such as weightlifting or CrossFit, the injury can also occur when the knee is extended after putting too much weight on the legs.

In many cases, along with an internal knee pop, a player may experience a sharp pain that forces them to fall to the ground. However, the sharpness and location of the pain depends on the:

  • Exact part of the body suffering the injury;
  • Ability to stand;
  • The feeling that the knee is locked or giving in. 

The knee may not swell immediately but a few hours after the injury.

At this point, it is strongly recommended not to resume playing or walk independently before consulting with a specialist. 

Knee pop: What to do right away

All players, even amateurs, should become familiar with the RICE protocol and implement it immediately after an injury:

  • Rest (no weight on the injured knee);
  • Ice;
  • Compress;
  • Elevate.

These, however, are only the first steps to follow on the field. 

An orthopedic evaluation right after the injury is crucial. In order to completely recover knee functions even after the most severe injuries, the necessary steps are:

  • Orthopedic examination;
  • Early specialist diagnosis;
  • Early and appropriate treatment. 

In general, if a ligamentous injury or sprain is suspected, even when the knee only presents 

swelling, bone fractures must be ruled out with an X-ray. These may be a consequence, for example, of contact trauma with another player, and require treatment to manage pain and monitoring. 

Knee pop: brace, rehabilitation or surgery

Often, a specialist may prescribe a specific knee brace and crutches immediately after a minor knee injury to avoid putting weight on the knee. Their use will vary based on the specific injury and its symptoms.

In cases of a severe injury, arthroscopic ligament reconstruction or meniscal suturing surgery may be necessary. As with conservative therapies, it is recommended not to wait too long before undergoing surgery. This is because when it comes to trauma, waiting may mean that other body parts surrounding the knee may be compromised.