Types of Knee Sprains, Strains, & Tears

The knee is both an essential and fragile part of the body. It’s an easy area to forget about, but a serious knee injury can derail your everyday life, hindering even the most basic of movements.

You can experience serious and non-serious knee injuries in a number of ways, but these injuries are not always the same. It’s important that you are able to identify what these injuries are so you know how to appropriately respond before seeking medical treatment.

Below you’ll find information on knee sprains, strains, and tears that can occur, and how to differentiate between them.

Knee Sprain Vs Tear

One of the most common misunderstandings when it comes to knee injuries is the difference between a sprain and a tear. People regularly equate the two terms, but they are not the same thing. Knee strains are also a form of injury that people may confuse with the aforementioned terms.

Sprains, tears, and strains are three types of knee injury. But how do they differ?

What is a Knee Sprain?

A knee sprain refers to an injury of the ligaments in the knee, whether by being overstretched or torn. The ligaments are the connective tissue that joins the upper and lower leg bones at the joint. The four major ligaments of the knee include the anterior cruciate ligament, the posterior cruciate ligament, the lateral collateral ligament, and the medial collateral ligament.

injured knee black and white image

Knee sprains are a common form of knee injury and are likely to affect athletes involved in sports like wrestling, soccer, and football. Knee sprain recovery time can take anywhere from a week to several months to fully heal, depending on the severity of the injury.

What is a Knee Tear?

A tear is an injury to the meniscus (two pieces of cartilage in between the knee joint, the medial and lateral menisci) or ligaments in the knee that are torn apart or detached from the bone. These injuries can be partial or complete. A tear in the knee tends to be more serious than a sprain or strain and can require rehabilitation and in some cases, surgery.

What is a Knee Strain?

A knee strain occurs when the tendons or muscle fibers around the knee are overstretched or torn. It is usually the result of overuse, overbending, heavy lifting, or a sudden blow to the knee. The severity of a knee strain can vary greatly – some sprains can be treated at home while others, in rare cases, may require surgery.

Types of Knee Sprains

  • Anterior cruciate ligament (ACL): The most common type of knee sprain, and one of the most common overall injuries in the US. ACL injuries are often accompanied by damage to the surrounding ligaments. They occur while jumping, twisting, and when a movement is suddenly stopped. ACL knee sprain symptoms include a “popping” sensation and significant swelling.


Image source

  • Posterior cruciate ligament (PCL): This ligament is found at the back of the knee, and is the most uncommon of the four types of knee sprain. It usually occurs as a result of other primary knee injuries and is caused by direct impact. Expect knee instability, pain, and swelling.
  • Lateral collateral ligament (LCL): The LCL is the ligament on the outside of the knee. The LCL is easily sprained and usually caused by direct contact, twisting, and repetitive movement. Symptoms include knee instability, pain, swelling, tenderness, and a “locking” sensation.
  • Medial collateral ligament (MCL): A supporting ligament inside the knee, MCL sprains are caused by stress or force applied to the outside of the knee. This happens while bending, twisting, and pivoting. Symptoms include swelling, pain, and a “popping” sensation in the knee.

Types of Knee Tear

  • Cruciate ligament tear: Complete or partial tearing of the ACL and PCL. These two ligaments connect the thigh bone to the lower legbone. The ACL is the most commonly torn ligament in the knee, whereas the PCL, the strongest ligament, is the least likely to be injured. Symptoms include a “cracking” sound, intense pain, knee instability, and immediate swelling. The knee will not bend or stretch.
  • Collateral ligament tear: Complete or partial tearing of the LCL and MCL. These tears usually only occur in conjunction with a cruciate ligament tear. Symptoms include mild to severe pain, stiffness, swelling, tenderness, and a locking or catching in the joint, and in the case of an LCL tear, numbness and weakness can occur near the ligament.
  • Meniscal tear: The two-piece of cartilage that “cushion” the shinbone and thighbone. Also known as “torn cartilage,” meniscus tears can occur during contact sports or as a result of degenerative microtears in elderly patients. Symptoms include “popping,” stiffness, swellness, difficulty straightening the knee, and the knee giving way.

Types of Knee Strain

Muscle strain in the knee can be differentiated by their grades of severity.

  • Grade 1: Some muscle fibers are overstretched or mildly damaged but the muscle remains largely intact.
  • Grade 2: More fibers are stretched and/or partially torn, and tendons may also be damaged. These strains are more painful and require more time to strengthen and rehabilitate the affected areas.
  • Grade 3: Significant damage, often including a complete tear and loss of function in the knee. This will lead to longer rehabilitation and possible surgery.

While the effects of a knee injury can range anywhere from mild to severe, it is always important to seek professional medical advice if you think you’ve damaged this part of your body.

If you’re looking for an orthopedic surgeon in Atlanta, get in touch with our team at Kellie Middleton MD. We specialize in knee injuries, pain management, physical therapy, and other sports-related injuries, so send an email or call 770-509-4030 to book your first appointment.

Leave a Comment

Your email address will not be published.