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Plantaris Muscle: Back Of The Knee Pain

The plantaris is a small muscle located behind the knee. It attaches to a long tendon that travels down the leg to connect to the heel.

The muscle causes pain behind the knee that occasionally descends into the top of the calf.

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    Where Is The Plantaris Muscle?

    Image of the origin and insertion points of the plantaris muscle.

    The plantaris muscle is found behind the knee. The muscle belly itself is small, about the size and length of your index finger. The muscle blends into the plantaris tendon which descends the leg to connect to the heel bone (calcaneus).

    Interesting Facts:

    • The plantaris is sometimes called the mini-gastrocnemius due to the common attachment to the thigh bone (femur).
    • The plantaris muscle is missing in approximately 10% of the population.

    What Does The Plantaris Muscle Do?

    Image demonstrating plantarflexion of the foot
      • It helps to bend the knee
      • It helps to point the foot and toes downward

    For detailed anatomy information:  Plantaris Muscle Anatomy

    Plantaris Muscle Pain Symptoms

    Image showing the plantaris muscle pain pattern

    The pain caused by the plantaris muscle centers in the back of the knee and occasionally refers down into the top of the calf. It may also contribute to cramps in the back of the lower leg.

    Signs and symptoms include:

    • Pain behind the knee
    • Pain will sometimes extend down into the calf
    • Is sometimes involved in cramps in the calf

    Other muscles, including the plantaris, contribute to these conditions

    Muscles With Similar Pain Patterns

    Popliteus Muscle

    Soleus Muscle

    What Causes Plantaris Muscle Pain?

    • Any activity in which the knee is straight while the ankle is simultaneously bent up toward the shin
      • Running
      • Pedaling a bike
      • While going downstairs, you miss a stair landing with the ankle bent and the knee straightened to the extreme.

    How To Avoid Development of Trigger Points In The Plantaris Muscle


    The plantaris muscle pain is seldom caused by overwork. The muscle itself is very small and does not initiate movement. Instead, it helps other muscles bend the knee and flex the foot.

    However, a fully straightened knee with the foot bent up toward the lower leg is the one position that strains the muscle. This usually happens when you slip off a curb, step, or walk down a steep incline. Kids and dancers may also experience pain behind the knee if they walk a considerable distance, balancing on their heels with the top of the foot raised.


    Plantaris Trigger Point Treatment

    Image showing plantaris muscle trigger point

    When dealing with knee pain, one of the first treatments many consider is a knee brace. While a brace may help with other types of knee injury and chronic pain, a brace or wrapping is usually NOT recommended for muscle pain behind the knee. Do not wrap or use a brace unless it is recommended by a medical professional.

    The plantaris muscle is easy to treat though you must not press on blood vessels and lymph nodes behind the knee. If you are interested in learning how to treat plantaris trigger points, The Trigger Point Therapy Workbook will provide guidance. The book provides instructions and diagrams that will help you locate and treat the trigger point.

    If you are not comfortable doing self-treatment, find a massage therapist, chiropractor, or physical therapist to walk you through finding the TrP and treatment.

    Plantaris trigger points respond best to 2-4 treatments spread throughout the day. Continue treatments until the area does not produce pain or symptoms when pressure is applied.

    How Long Before I Feel A Reduction In Pain?

    The good news is that you will begin feeling relief quickly. Treat the trigger point 2-3 times throughout the day for 1-2 minutes each treatment. If the back of the knee begins to feel sore, decrease the pressure, and treat twice a day, morning and night.

    Keep in mind that you need to continue treating the trigger point until the area is not painful when pressure is applied.

    Other muscles that should be considered and examined:

    Products We Use and Recommend For Plantaris Muscle Pain

    Sombra Warm Therapy Gel is recommended for relaxing muscles and relieving pain. It warms without the burning heat of other gels. An excellent choice for pain caused by trigger points, muscle/joint over-use and stiffness, and arthritis. If you have reoccurring leg or foot cramps, you should keep Somba on hand; it provides almost instant relief. (Not sold in stores)

    Biofreeze Pain Relieving Gel is an excellent pain-relieving gel recommend for those who have sudden onset muscle pain or recent injuries.  It is better to use than warm therapy gels and creams for muscle pain caused by inflammation as it cools the area much like ice. If your pain is from a recent injury, use Biofreeze. It is excellent to use on sprains, strained and sore knees.

    Plantaris muscle pain and symptoms can be similar to, contribute to, and be affected by these medical diagnoses:

    • Popliteus tendinitis
    • Popliteal artery aneurysm
    • Avulsion of popliteus tendon
    • Rupture of plantaris tendon
    • Baker’s cyst
    • Deep Vein Thrombosis
    • Peripheral Vascular Disease
    • Posterior compartment syndrome