May 20, 2023

A Guide to Physical Therapy for a Knee Sprain

Knee strains and sprains account for more than 40% of emergency room visits, regardless of the cause. Of these injuries, some studies estimate that as high as 50% of these visits were related to sports injuries.1

The knees play an important functional role in allowing us to ambulate and participate in activities of daily living and recreational pursuits, whether it's playing a game of soccer, going for a jog, climbing stairs, or getting out of the car. A knee sprain can have a big impact on the way we participate in our daily lives.

Working with a CityPT clinician can help boost your knee sprain recovery potential and get you back to the activities you love as soon as possible. Keep reading to learn about symptoms, causes, diagnosis, treatment, and prevention tips for a sprained knee.

Table of Contents

Understanding Knee Sprains

A sprain specifically refers to the injury of a ligament. A ligament is a strong, often rope-like, band of connective tissue that connects two or more bones to a joint. Ligaments throughout the body play a key role in providing passive stability to the joints. Plus, they also help the joint with spatial orientation and act as a sensor to provide proprioceptive feedback (knowing where your limb is in space).

A knee sprain occurs when one or more of the ligaments that support the knee joint is overstretched or torn.

The Ligaments of the Knee

There are 4 ligaments around the knee that provide innate stability.

  • Medial collateral ligament (MCL): Located on the inner side of the knee joint
  • Lateral collateral ligament (LCL): Located on the outer side of the knee joint
  • Anterior cruciate ligament (ACL): Located inside the knee joint to prevent excessive forward movement — one of the most commonly torn ligaments (see more about ACL tears), particularly in athletes2
  • Posterior cruciate ligament (PCL): Located inside the knee joint to prevent excessive backward movement

How to Classify a Knee Sprain

In order to properly classify a knee sprain, we need to consider both the severity of the injury as well as which ligament has been damaged. There are 3 grades for classifying a sprain:

  • Grade I: The ligament has been stretched, but there are no microscopic tears
  • Grade II: The ligament has sustained partial tearing (less than 50%)
  • Grade III: The ligament has been severely torn (more than 50% of the fibers) or completely torn1

Symptoms of a Sprained Knee

The symptoms of a knee sprain can vary depending on the ligament affected and the severity of the injury. However, the most common symptom is pain. It's important to note that the location of the pain can help determine which ligament is sprained. Other common symptoms may include:

  • Decreased range of motion and joint stiffness
  • Muscle weakness (due to pain and protective mechanisms)
  • Swelling and/or bruising around the knee joint
  • Tenderness to touch over the ligament
  • Knee joint instability or a "giving way" feeling

What are the Most Common Causes of a Knee Sprain?

Knee sprains can occur from a traumatic event (like a fall or contact injury) or from overuse. In terms of contact injury, this is often seen in athletes who participate in high-demand sports, such as football, soccer, and hockey. Non-contact knee sprains often occur in activities where there is a lot of cutting, like basketball, tennis, and volleyball.

Certain risk factors can predispose someone to a greater likelihood of sustaining a knee sprain. These include:

  • Poor proprioception or balance (a sense of where your limb is in space)
  • Impaired muscle control or joint stability (weakness, tightness, etc.)
  • Muscle or joint stiffness that limited normal mechanics
  • Altered mechanics during high-demand activities
  • Participation in high-impact sports or any activity that requires frequent changes in direction

Which ligament is injured depends on the direction of the trauma or repetitive sustained force. For example, an ACL tear is more likely to occur from a twisting force (like when your foot is planted and your knee twists), whereas an MCL tear is more likely to occur from a direct blow to the outer side of the knee.

Diagnosing a Knee Sprain

When a knee is injured from a trauma, it is often hard to differentiate between a fracture and a ligamentous injury due to the severity of pain, swelling, and difficulty weight bearing. Thus, it's important to seek medical attention to get an accurate diagnosis.

After taking a thorough history and performing a physical examination, your healthcare provider will likely order imaging tests to further evaluate the structures around your knee and rule out other knee injuries. These may include an x-ray, MRI, or CT scan.

What to Expect from Physical Therapy for a Knee Sprain

Once an accurate diagnosis has been made, treatment can begin. One of the most effective treatment options available is physical therapy.3

Working with a CityPT physical therapist, you will develop an individualized plan of care that is based on your specific goals, needs, and the findings from your initial evaluation. In general, treatment for a knee sprain will focus on reducing pain and inflammation, regaining range of motion and strength, and improving joint stability.

A few specific treatment techniques that may be used include:

  • Manual therapy to help reduce pain and inflammation and improve range of motion
  • Therapeutic exercises to improve strength, control, and joint stability
  • Advice on how to gradually and safely return to previous activities
  • Balance and proprioception training
  • Education about your injury and recovery process
  • Pain management strategies

Your physical therapist will also provide you with guidance on how to protect your knee during activities and when to return to your previous level of activity. They may also recommend the use of braces, supports, or other assistive devices as needed.

How Long Does a Sprained Knee Take to Heal?

Sprained knee recovery time varies depending on the severity of your injury, overall health, and whether surgery was needed or not. In general, most people with grade 1 and 2 sprains can expect to see significant improvements within 4 to 6 weeks with conservative treatment. However, some may still experience ongoing symptoms (like knee instability or pain with certain activities) beyond this time frame.

Due to individual differences, it's important to work with a movement specialist to make sure you don't return to activities or sport too soon, which increases risk of re-injury.

If surgery is needed due to knee instability or a severe/complete tear, rehabilitation will be more extensive and may take six or more months. The good news is that with focused physical therapy, the vast majority of people are able to return to their previous level of activity.

Preventing Knee Sprain

While there's often no way to avoid a knee sprain, there are a few things you can do to help reduce your risk, including:

  • Sport specific protection: Wearing appropriate shoes and using proper technique when participating in sports or other activities
  • Training volume: Gradually increasing the intensity and duration of your activity to allow your body to adjust
  • Cross-training: Participating in a variety of activities to reduce the risk of overuse injuries
  • Consistent exercise: To Keep your muscles strong, flexible, and healthy
  • Sports biomechanical training: Participating in challenging and dynamic movements specific to your sports or activities
  • Weight management: Maintaining a healthy weight to reduce stress on your joints
  • Talk to an expert: Talking to a sports physical therapist with CityPT about your concerns and getting personalized recommendations based on your goals, history, and movement patterns
  • Make healthy choices: Support your overall tissue health with good lifestyle habits, such as adequate sleep, nutrition, and stress management

Is It Time to Seek Treatment?

Early diagnosis and treatment of a knee sprain can help promote healing, reduce the risk of further injury (and onset of arthritis), and get you back to your previous level of activity more quickly.

Are you wondering how to heal a knee sprain quickly? Focus on healing your knee sustainably to prevent the risk of future complications — like chronic pain, re-injury, and disability. A CityPT can help guide you on your path to recovery and get back to your normal life routine.

Book an appointment now.

This guide is intended for informational purposes only. We are not providing legal or medical advice and this guide does not create a provider-patient relationship. Do not rely upon this guide (or any guide) for medical information. Always seek the help of a qualified medical professional who has assessed you and understands your condition.



  1. Gray AM, Buford WL. Incidence of Patients With Knee Strain and Sprain Occurring at Sports or Recreation Venues and Presenting to United States Emergency Departments. J Athl Train. 2015 Nov;50(11):1190-8. doi: 10.4085/1062-6050-50.11.06. Epub 2015 Nov 2. PMID: 26523662; PMCID: PMC4732399. 2

  2. Evans J, Nielson Jl. Anterior Cruciate Ligament Knee Injuries. [Updated 2022 May 5]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK499848/

  3. Knee Ligament Sprains and Tears: Clinical Practice Guidelines Ensuring Best Care. Journal of Orthopaedic & Sports Physical Therapy; 2017 (47:11), 824-824.

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