Key Points about Knee Strain or Sprain

  • A knee sprain damages ligaments, while a strain damages the knee’s tendons or muscles.
  • Strains often result from overuse or a sudden increase in pressure on the joint, while sprains often result from falls or collisions during contact sports other physical activities.
  • Knee strains or sprains can cause swelling, pain and tenderness in the affected knee, as well as buckling and trouble bending the knee.
  • While many strains and sprains can be treated at home, you should call your doctor immediately if your knee pain is so severe that you cannot walk or bend the knee.
Common related conditions
Knee Arthritis Knee Dislocation Knee Fractures Patellar Tendinitis Thigh and Lower Leg Fractures Patellofemoral Pain Syndrome

Overview

While they both affect the knee joint, knee sprains and strains are separate conditions. A knee sprain causes damage to the knee’s ligaments, while a strain causes damage to the muscles or tendons.

Symptoms will vary depending on the type and severity of the injury, but may include swelling, tenderness and pain in the affected joint.

Many strains and sprains do not need medical attention and can be treated at home with rest, ice and over-the-counter pain-relievers. If you have extreme knee pain that is preventing you from walking or bending the knee, however, you should see a doctor immediately. 

Knee strain or sprain causes

Knee strains occur when a tendon or muscle in the knee is damaged, often from overuse or a sudden, dramatic increase of use of the knees.

Common causes of knee sprains include:

  • A fall, collision or other hit to the body, such as during a contact sport
  • Placing sudden, excessive weight on the knee joint
  • An abrupt twist of the knee joint

Knee strain or sprain risk factors

You may be at an increased risk of experiencing a knee sprain or strain if you:

  • Play contact or non-contact sports
  • Have impaired balance or coordination
  • Have muscle weaknesses or inflexibilities in the leg

Knee strain or sprain symptoms

Knee strains and sprains can range from moderate to severe, and symptoms will vary accordingly.

General symptoms of a knee strain or sprain include:

  • Swelling, pain and tenderness in and around the knee
  • Buckling of the knee
  • Trouble bending the leg

Symptoms of a knee sprain will further depend upon which ligament, or ligaments, have been torn.

Knee strain or sprain prevention

While some knee injuries result from accidents that are hard to prevent, you can reduce your risk of knee sprains or strains by:

  • Wearing proper, supportive footwear when exercising
  • Always warming up before exercising
  • Stretching and strengthening the leg muscles
  • Making changes to your exercise or training regimen incrementally, not suddenly

Knee strain or sprain diagnosis

When diagnosing a possible knee sprain or strain, your doctor will ask about how the pain started, including whether the pain started immediately following in injury, or developed gradually over time.

Your doctor will also examine the affected knee, looking for:

  • Swelling
  • Altered knee shape
  • Tenderness
  • Discoloration
  • Fluid in the joint

Your doctor may recommend the following imaging procedures as well:

  • X-ray
  • MRI scan
  • Arthroscopy

Knee strain or sprain treatment

After consulting a doctor, you can generally treat mild knee sprains and strains at home, by:

  • Resting, icing, compressing and elevating the joint
  • Taking over-the-counter anti-inflammatories, as needed
  • Following a physical therapy routine, provided by your doctor

Severe sprains may require additional measures such as surgery to repair the damaged tissues.  

When to seek care

Call your doctor if you are unable to walk due to knee pain, if you are unable to move the knee, or if you have extreme pain or swelling in the area.

Next Steps

Your doctor will assess your symptoms and provide a diagnosis and treatment plan accordingly.