In this section I want to talk about knee sprains. As a pain management practitioner, I often treat patients for knee sprains caused by a motor vehicle accident (MVA), sports injury, or a slip and fall. My patients, who injured their knee(s) during a motor vehicle accident, often have the same story. Baring down on their brakes, they cause their legs to overextend to prevent their car from moving forward and impacting the car in front of them, or they hit their knees on the dashboard during impact. Many of the athletes who have random slips and falls report twisting or landing in an unusual way. Because everyone has diverse levels of pain tolerances, it’s particularly important to recognize the signs and symptoms of a knee sprain and treat it accordingly. Read the information below for more details on how to recognize various knee sprains and how to treat them.
What is a knee sprain?
A knee sprain is an injury to a ligament(s) in the affected knee. A ligament is the tough, rubbery tissue that connects the femur (upper bone) to the tibia (lower bone) of the leg at the knee joint.
There are four ligaments in the knee.
- Anterior Cruciate Ligament (ACL)
▪ The ACL forms an “X” with the PCL to connect the inside of the knee joint to stabilize the knee against front to back and back to front movements.
▪ ACL sprains occur during a sudden stop, a twist or pivot, or a change in directions at the joint.
▪ ACL sprains can also be caused by extreme overstretching (hyperextending).
▪ Direct impact to the outside of the knee or lower leg.
▪ ACL sprains are often seen in athletes who play in these sports: football, basketball, soccer, rugby, wrestling, gymnastics, and skiing. - Posterior Cruciate Ligament (PCL)
▪ PCL sprains occur from the direct impact to the front of the knee.
▪ Examples include hitting your knee on the dashboard during a car accident or landing on a bent knee while playing a sport.
▪ PCL sprains are common in football, basketball, soccer, and rugby athletes. - Medial Collateral Ligament (MCL)
▪ The MCL supports the inner side of the knee.
▪ MCL sprains occur during the direct sideways blow to the outside of the knee and lower leg.
▪ Injuries can also occur from a severe twist while skiing or wrestling.
- Lateral Collateral Ligament (LCL)
▪ LCL supports the outer knee.
▪ LCL is the least likely ligament to be sprained because most LCL injuries are caused by a blow to the inside of the knee, which is shielded by the opposite leg.
Causes
● A direct blow to the knee (MVA or sports injury)
● A twist of the knee joint
● A fall onto a bent knee
Signs and symptoms
● Immediate pain in the knee after a direct blow or twist
● Pain with movement or activity in the knee
● Swelling and bruising of the knee
● Walking with a limp or a feeling that the knee will “give out” with standing and walking
● The feeling of a “pop” or “snap” felt in the knee when the injury occurred
Diagnosis
If someone you know or you are having these symptoms, please schedule an appointment to see your primary care provider. Your provider will do the following:
● Perform a physical assessment to determine which ligaments are affected from the injury.
● Order an Xray of the affected knee to rule out fractures.
● Order an MRI of the affected knee (may be necessary based on the severity of the injury and pain) to assess for torn ligaments and menisci.
Treatment
Treatment depends on the severity of the injury, the patient’s age, activity level, and if an additional injury is present.
● NSAIDs (Ibuprofen or Naproxen) for pain
● Rest to allow the muscles, ligaments, and swelling to heal
● Ice for reducing the swelling and pain
● Elevation of the leg to help reduce the swelling
● Splint applied to the knee to provide support and prevent future damage
● Crutches (may be necessary based on the severity of the injury),
● Orthopedic consult (if abnormalities are seen on the X-ray and/or MRI report)
References
Harvard Health Publishing: Harvard Medical School. (2019). Knee Sprain: What is it? https://www.health.harvard.edu/a_to_z/knee-sprain-a-to-z
Levy, D.B. (2021). Knee Soft Tissue Injury (ACL, LCL, MCL, PCL) Management in the ED Clinical Presentation. Medscape. https://emedicine.medscape.com/article/826792-overview NYU Langone Health. (2022). Medical Therapies for Knee Sprains, Strains & Tears. https://nyulangone.org/conditions/knee-sprains-strains-tears/treatments/medical-therapies-for-knee-sprains-strains-tears
Victoriia_P. (2022). [Illustration]. Anatomy. Knee Joint Cross Section Showing the major parts which made
the knee joint For Basic Medical Education Also for clinics. https://www.shutterstock.com/image-illustration/anatomy-knee-joint-cross-section-showing-505690135