Skip to content

Flexor Hallucis Longus Muscle: Big Toe Pain

The flexor hallucis longus muscle attaches to the small bone in the back of the lower leg, traveling down the leg attaching to a bone in the big toe.

The muscle contributes to pain on the bottom of the big toe and sometimes radiates into the ball of the foot. The muscle also plays a role in the development of hammertoe.

Follow Us

Table of Contents

    Where Is The Flexor Hallucis Longus Muscle?


    The flexor hallucis longus is located in the back of the lower leg. The muscle attaches to the small bone of the lower leg (fibula) and extends down the back of the leg into the bottom of the foot, where it connects to the bottom of the big toe (distal phalanx of the hallux).

    Interesting Facts:

    • Numbness felt on the bottom of the big toe is a classic sign of flexor hallucis longus dysfunction.
    • Pain caused by the flexor hallucis longus muscle is often diagnosed as gout. If you have been diagnosed with gout and medication does not seem to be working, examine the muscle for trigger points, soreness, and tightness.

    What Does The Flexor Hallucis Longus Muscle Do?

    Image demonstrating plantarflexion of the foot
      • It bends the big toe downward
      • It assists in bending the foot downward and pointing your toes (plantarflexion)
      • It helps in balance while walking and standing
      • It is one of the muscles that propel the body forward for a smooth walking gait

    For detailed anatomy information:
    Flexor Hallucis Longus Anatomy

    Flexor Hallucis Longus Pain Symptoms


    The flexor hallucis longus will cause pain at the bottom of the big toe that often radiates into the ball of the foot. Another common symptom is a feeling of numbness in the big toe that goes down into the ball of the foot beneath the big toe.

    Signs and symptoms include:

    • Pain in the big toe radiating to the ball of the foot
    • Numbness on the bottom side of the big toe

    Other muscles, including the flexor hallucis longus, contribute to these conditions

    Muscles With Similar Pain Patterns

    Flexor Hallucis Brevis Muscle

    Flexor Digitorum Longus Muscle

    Recommended Muscle Pain Products

    Doctors and physical therapists often recommend using a TENS at home to relax muscles and ease the pain. The Belifu TENS Unit Muscle Stimulator is highly recommended and an excellent choice for treating upper and lower leg 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)

    What Causes Flexor Hallucis Longus Pain?

    The footwear that we choose directly affects the flexor hallucis longus muscle. Poor-fitting shoes lead to pain. If your shoes are too small, the foot and toes are cramped, leading to pain and deformity of the toes. If your shoes are too big, your feet slide around in the shoes causing the foot and lower leg muscles to overwork trying to maintain balance and work to keep the shoe on the foot.

    Flip flops and other open-heeled shoes are especially detrimental to the flexor hallucis muscle. The toes are constantly gripping the shoe to hold the shoe in place, which creates muscle imbalances in the lower leg and foot muscles leading to pain and discomfort. The pain caused by these muscle imbalances can work its way up into the knees, hips, and lower back.

    High heels contribute to pain in the flexor digitorum hallucis muscle and other foot and leg muscles. High heels throw the balance of the body off because you are balancing only on the ball of the foot and not the entire foot. Frequently wearing high heels can also lead to bunions, hammertoe, and claw toes.

    Other common causes of flexor hallucis longus pain are walking or jogging on uneven ground or deep sand. Again, the toes tend to try to grip the ground to maintain balance, overworking and stressing the muscle.

    The Causes of Pain

      • Running or walking on uneven ground
      • Immobility in the big toe joints due to arthritis or injury
      • Worn shoes
      • Shoes that do not have proper padding in the ball of the foot
      • Wearing flip flops and other open heeled shoes
      • Wearing high heels
      • Walking or running barefoot in deep sand

    How To Avoid Development of Trigger Points In The Flexor Hallucis Longus Muscle

      • Wear shoes that fit your foot! Properly fitting shoes are paramount to foot, leg, and back health.
      • Don't wear flip-flops as your primary shoes. Though they are comfortable, they stress the foot and leg muscles, leading to pain and discomfort.
      • Walking and jogging on uneven ground or deep sand can be good exercises for the foot and lower leg muscles. However, if your muscles are not accustomed to these surfaces, it can lead to sore muscles and the development of trigger points.

    Flexor Hallucis Longus Trigger Point Treatment


    Even though trigger points in the flexor hallucis longus refer pain to the bottom of the big toe and ball of the foot, the treatment is applied to the lower leg under the knee.

    To learn how to treat flexor hallucis longus trigger points, TWD recommends The Trigger Point Therapy Workbook. The workbook provides diagrams and instructions about finding the trigger point and how to do the treatment. The workbook is recommended to all interested in learning about trigger points and the treatment of muscle pain.

    If you are uncomfortable trying self-treatment, you should consider finding a massage therapist, physical therapist, athletic trainer, or chiropractor trained in trigger point therapy. They can show you how to find and treat the TrP and suggest exercises and stretches that will help balance the muscle.

    For the best outcome, trigger points should be treated several times throughout the day until the knot is gone and the area does not produce pain when pressure is applied.

    How Long Before I Feel A Reduction In Pain?

    Many begin feeling relief after the first day of treatments. For others, it may take a few days to notice a difference. For complete and successful treatment, it is crucial to continue direct pressure and massage until the trigger point is deactivated. When the area around the trigger point no longer is sore or sends pain into the foot, it is deactivated.

    Other muscles that should be considered and examined:

    Satellite trigger points associated with the flexor hallucis longus muscle:

    Trigger points in one muscle will cause TrPs to develop in other muscles. These are known as satellite trigger points. You will need to check these muscles for additional TrPs.

      • Tibialis posterior
      • Extensor digitorum longus
      • Extensor digitorum brevis

    Products We Use and Recommend For Low Leg Muscle Pain

    The Roxofit Calf Support/Shin Splint provides support and warmth to the lower leg muscles. This brace is recommended for Achilles tendon strains, sprains, and also strains, sprains, and overuse injuries of the lower leg muscles. An excellent choice for compression and support of the lower leg muscles. If you suspect or have ever been diagnosed with blood clots, consult your doctor before using this brace.


    Sore shins or calves? Feel as if shin splints are coming on? The ProStretch Calf Stretcher & Foot Rocker can help! The stretcher/rocker stretches and helps relax most of the muscles in the lower leg and foot. Physical therapists use them to treat sore shins and calves as well as foot pain and plantar fasciitis.


    Yoga Toes Gems are highly recommended for anyone dealing with foot and lower leg pain. The separators stretch the muscles of the feet and many muscles of the lower leg. Used regularly, Yoga Toes do help straighten and align your toes. They can also be helpful for some cases of bunions, hammertoes, and claw toes. It can also help with issues of plantar fasciitis. I prefer the Yoga Toes Gems because they are more supple, comfortable, and easier to use. To increase treatment, relax while wearing Yoga Toes and then use massage balls to roll the soles of the feet.

    For Men's shoe size ten and over or women's shoe size 12 and over, consider Yoga Toes For Men.

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

      • Tarsal tunnel syndrome
      • Hammer toe
      • Turf toe
      • Bunion
      • Gout