Plantar Fasciitis: Anatomy and Causes


Plantar-fasciitis-heel-painPlantar Fasciitis is a painful inflammatory condition felt on the bottom of the heel.  It is caused by excessive pressure and stretching of the Plantar Fascia where it inserts at the heel bone.

Typically, a person experiences intense pain first thing in the morning when stepping out of bed and often on taking the first steps after arising from a sitting position.

Pain can be achy, stabbing or burning and is usually felt on the underside of the heel, on the inner heel.


Left untreated, Plantar Fasciitis can affect both heel and become chronic, progressing to consistent pain throughout the day.

Causes of Plantar Fasciitis

Plantar Fasciitis is caused by repetitive strain to the foot and leg muscles, joints and connective tissue. It is most commonly associated with and aggravated by standing, walking and/or running excessively.

Activities that can lead to this type of strain include:

  • standing and walking for many hours a day at work
  • running and exercise that is done excessively or without proper training
  • wearing shoes with poor arch and ankle support

Anatomical or Inherited Causes of Plantar Fasciitis include:

  • low foot arches (flat feet) or high foot arches that predispose to biomechanical dysfunction and tissue strain
  • thinning of the fat pad of the heel that can occur with age
  • leg length difference related to Osteoarthritis, hip or knee surgery or leg fracture

The good news is that treatment for Plantar Fasciitis is available and effective. Plantar Fascia Exercises can be learned to help alleviate inflammation and pain. You can also purchase specialized compression socks and sleeves to reduce swelling and pain and that add support.

The Plantar Fascia is a connective tissue that arises from the undersurface of the heel bone, extending forward and inserting into the metatarsal-phalangeal joint capsules of all 5 toes. It continues backward on the heel bone, as periosteum (which has pain-sensitive nerve fibers and is vascular connective tissue).

Anatomists have discovered that the Plantar Fascia maintains connections with the Achilles paratenon (sheets of dense connective tissue that form an elastic sleeve to separate the Achilles tendon from deeper connective tissue).

The Achilles paratenon is rich in blood vessels, nerves and allows the Achilles tendon to glide over nearby structures more easily, thereby reducing wear and tear. The paratenon has a greater nerve supply than the Achilles tendon itself, with numerous nerve endings and Ruffini and Pacini corpuscles (mechanoreception and proprioception).

The Plantar Fascia also has connecting septa with flexor tendons and lumbrical muscles of the foot, which demonstrate a strong relationship between these structures and suggest that the Plantar Fascia has a role in both perceiving the state of contraction of various intrinsic foot muscles and in controlling the foot’s position and therefore stability.

Knowledge of this anatomy can help us to understand that excessive stretching, contraction and tightness of the Achilles tendon and intrinsic foot muscles due to overuse, improper footwear, etc. can lead to an inflamed and overstretched fascia and are risk factors of Plantar Fasciitis.

Treatment should focus not only on the fascia of the foot but also on the foot joints and deep foot muscles, calf and hamstring muscles.

At Toronto Orthotics Foot and Leg Pain Clinic, we offer on-site treatments that may be required for Plantar Fasciitis.

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Foot & Leg Pain Clinic

Let us help you with the pain of Plantar Fasciitis!


Contact us by calling (647) 349-4909. For a copy of Dr. Horowitz’s recommended running shoe list for people who wear custom orthotics or to ask Dr. Horowitz a question, fill out this form below: