GENERAL INFORMATION
The plantar muscles in the foot play a crucial role in various movements and functions, including walking, running and maintaining balance. These muscles work together to provide stability and support to the foot arches.
ORIGIN
These muscles have different points of origin based on their specific location within the foot. The origins of the significant plantar muscles are as follows:
- Flexor digitorum brevis: Medial tubercle of the calcaneus (heel bone)
- Abductor hallucis: Medial process of the calcaneal tuberosity (heel bone)
- Flexor hallucis brevis: Cuboid bone and lateral cuneiform bone
- Quadratus plantae: Calcaneus (medial surface) and the tendon of the flexor digitorum longus muscle
- Flexor digiti minimi brevis: Base of the fifth metatarsal bone.
INSERTION POINT
The plantar muscles have various insertion points based on their specific functions. The significant insertions of these muscles are as follows:
- Flexor digitorum brevis: Middle phalanges of the second to fifth toes
- Abductor hallucis: Medial side of the proximal phalanx of the great toe (first toe)
- Flexor hallucis brevis: Base of the proximal phalanx of the great toe
- Quadratus plantae: Flexor digitorum longus tendon (lies deep to it) and the tendon of flexor digitorum brevis (medial part)
- Flexor digiti minimi brevis: Base of the proximal phalanx of the fifth toe.
MAJOR ARTERIES
The plantar muscles receive their blood supply from various arteries, including:
- Plantar arteries: These arteries branch from the posterior tibial artery and provide blood supply to the plantar aspect of the foot, including the plantar muscles.
NEURAL INNERVATION
The plantar muscles are innervated by branches of the tibial nerve, specifically the medial and lateral plantar nerve.
TRIGGER POINT
Trigger points, or localised areas of muscle tension and sensitivity, can develop in the plantar muscles due to various factors such as overuse, muscle imbalances or trauma. These trigger points can cause pain and discomfort, often called plantar fasciitis or plantar heel pain syndrome.
CONCENTRIC FUNCTION
The plantar muscles primarily function concentrically to contract and generate force during movements such as plantar flexion (pointing the foot downward) and toe flexion.
ECCENTRIC FUNCTION
These muscles also function eccentrically to control the movement and decelerate forces acting on the foot, particularly during movements such as dorsiflexion (lifting the foot upward) and toe extension.
ISOMETRIC FUNCTION
Isometric contractions of the plantar muscles occur when the muscles generate force without changing their length. These contractions provide stability to the foot and maintain posture during weight-bearing activities.
RELATED MUSCLE SCIENTIFIC NAMES
Other muscles related to the plantar muscles include:
- Flexor digitorum brevis: Musculus flexor digitorum brevis
- Abductor hallucis: Musculus abductor hallucis
- Flexor hallucis brevis: Musculus flexor hallucis brevis
- Quadratus plantae: Musculus quadratus plantae
- Flexor digiti minimi brevis: Musculus flexor digiti minimi brevis
ANTAGONIST
The antagonist muscle to the plantar muscles is:
- Anterior tibialis: The anterior tibialis muscle is an antagonist to the plantar muscles during movements such as dorsiflexion and toe extension.
COMMON INJURIES
Joint injuries or conditions associated with these muscles include:
- Plantar fasciitis: Inflammation or irritation of the plantar fascia, a thick band of tissue that supports the foot arch and connects the heel bone to the toes.
- Muscle strains: Overstretching or tearing these muscles due to excessive force or improper foot mechanics.
- Tendinitis: Inflammation of the tendons that attach the plantar muscles to the bones, often caused by repetitive movements or overuse.
EXERCISES
Exercises that target the plantar muscles include:
- Calf raises: Perform heel raises by standing on a raised surface and lifting your body onto your toes, emphasising the contraction of these muscles.
- Toe curls: Place a towel on the floor, use your toes to scrunch and pull the towel toward you, working on flexion and strengthening these muscles.
- Resistance band exercises: Use resistance bands wrapped around your foot and perform resistance exercises, such as ankle plantar flexion and toe flexion against the resistance.
- Arch strengthening exercises: Perform exercises that target the arches of the foot, such as arch lifts and arch presses.
STRETCHES
Stretches that can help stretch the plantar muscles include:
- Calf stretch: Stand facing a wall, place one foot forward with the knee slightly bent and lean toward the wall, keeping the back heel on the ground. This stretch helps elongate these muscles and the calf.
- Toe stretch: Sit on a chair and cross one leg over the opposite thigh. Interlace your fingers between your toes and gently pull them back, stretching these muscles and toes.
- Plantar fascia stretch: Sit on a chair and cross one leg over the opposite thigh. Pull the toes upward using your hand, stretching the plantar fascia along the bottom of the foot.
- Marble pickup: Place marbles on the floor, use your toes to pick them up, and place them in a small container, which helps to improve the flexibility and skill of these muscles.