What is Plantar Fasciitis? An in-depth guide

What is the Plantar Fascia?

The Plantar Fascia is a thick band of tissue that runs from the heel bone (medial process of the calcaneal tuberosity) to the base of the toes (proximal phalanges) and consists of strong, densely packed collagen fibres.

This structure has an essential role in the maintenance of the longitudinal arch. The attachment and insertion sites of the plantar fascia allows the ligamentous structure to fulfil its role in preventing arch flattening.

An additional role of the plantar fascia is to dynamically provide stability to the foot and this is done via the Windlass Mechanism. In terminal stance, passive dorsiflexion of the metatarsophalangeal joints (toes) that occurs as the heel lifts off the ground, produces increased tension in the plantar fascia. This tension results in elevation of the arch and greater stability in the foot region.

Due to the stretch and tension invoked onto the plantar fascia during the terminal stance phase of gait, potential energy is able to be stored. As the toe off phase occurs, the foot is in motion and propulsion is assisted via the elastic recoil energy produced in the plantar fascia along with active muscle forces. The plantar fascia therefore has an essential role in walking, functioning as a ‘spring’ to propulse the body forward over the foot.

What is Plantar Fasciitis?

Plantar Fasciitis is an inflammation of the tissue on the plantar aspect of the foot, the plantar fascia, and involves the accumulation of damaged collagen fibres. This condition often presents in individuals aged 40-60 years old and is commonly seen as an overuse injury in running populations. Non-athletic populations can also experience plantar fasciitis and some of the predisposing factors include ankle and knee joint architecture (varus knee, cavus foot), high training volumes (overuse), use of spiked athletic shoes, unsupportive footwear, increased BMI, standing for prolonged periods of time, limited ankle dorsiflexion range and certain types of uneven walking surfaces/environments.

Certain clinical findings suggestive of plantar fasciitis include a tight plantar fascia that is painful upon stretch along with tight plantarflexors at the calf region (gastrocnemius and soleus muscles), pain and tenderness on the medial aspect of the inferior heel (attachment side of the plantar fascia to the calcaneal tubercle), and the possible presentation of a calcaneal spur however, this is not an essential feature. The typical pain pattern is as follows: pain noted on the first step upon waking, after prolonged standing and/or prolonged rest.

Diagnosis of Plantar Fasciitis:

Aspects of a physical examination as well as social and medical history suggesting overload of the plantar fascia tissue are noted by clinicians. These details assist them in diagnosing plantar fasciitis. Often imaging is not needed for diagnosis, however, clinicians may request an image to rule out differential diagnoses such as the presence of a possible stress fracture or a suspected bony spur being the source of pain. An image may also be suggested to observe the degree of irritation and inflammation of the plantar fascia tissue and surrounding structures following diagnosis.

Treatment of Plantar Fasciitis:

Conventional physiotherapy management plans of this overuse type injury are developed according to the tissue stress model. Essentially, findings alluding to an overloaded or compromised plantar fascia are present and a diagnosis of plantar fasciitis is confirmed. Investigation into the cause of overload then occurs i.e. consideration of forces, alignment and kinematics. The cause of overload is addressed in the early stages by reducing the load on the tissue via relative rest and/or modification of aggravating activities (such as running). Appropriate and supportive footwear is highly encouraged to be worn throughout the day when loading the lower extremities as a form of offloading the plantar fascia. Following the acute period, exercise in the form of calf raises, marble pickups, toe curls, etc. is utilised to restore strength and function (Thong-On et al., 2019). Long term management can involve reducing body weight if applicable as, in conjunction with the tissue stress model, a higher BMI causes greater loading through the lower limb complex and plantar fascia. Additionally, symptom management through massage, release and taping can be utilised to assist in easing the intensity and duration of pain (Juchli, 2021, and Podolsky & Kalichman, 2015).

Evidence exists for tissue specific plantar fascia stretching reducing plantar heel pain (Digiovanni et al., 2006). Static stretching of the plantar fascia and calf with a straight and bent knee is often prescribed in the management of plantar fasciitis with evidence showcasing improvements in pain and gait parameters (Thong-On et al., 2019).

In treatment of plantar fasciitis there is also a role for eccentric loading. Eccentric exercise aims to normalise collagen fibre alignment by gradually loading tissue in a lengthened position to realign disordered fibres. Eccentrically loading the calf musculature, in combination with conventional physiotherapy treatment, showcases greater improvements in the foot function index and pain in plantar fasciitis compared to conventional treatment alone (Rupareliya et al., 2015).

The plantar fascia, being a major contributor to the support of the medial longitudinal arch, is able to be offloaded through the use of prefabricated orthotics which simply provide mechanical arch support. This is deemed effective in the short term management of plantar fasciitis with evidence showcasing benefits to function and reductions in pain (Landorf et al., 2006).

Additionally, valgus wedging of the forefoot has been shown to decrease strain through the plantar fascia in biomechanical testing (Kogler et al., 1999). Thus, this can be considered as a treatment option for plantar fasciitis.

There is a good prognosis linked with plantar fasciitis and various methods to management. Most individuals that are treated conservatively recover within several months (Mayo Clinic, 2022).

Static seated plantar fascia stretch

Image 1 retrieved here

Eccentric loading of calf

Image 2 retrieved here

Lateral (valgus) wedging

Image 3 retrieved here

References

– Mayo Foundation for Medical Education and Research. (2022a, January 20). Plantar fasciitis. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/plantar-fasciitis/diagnosis-treatment/drc-20354851

– Thong-On, S., Bovonsunthonchai, S., Vachalathiti, R., Intiravoranont, W., Suwannarat, S., & Smith, R. (2019). Effects of strengthening and stretching exercises on the temporospatial gait parameters in patients with plantar fasciitis: A randomized controlled trial. Annals of Rehabilitation Medicine, 43(6), 662–676. https://doi.org/10.5535/arm.2019.43.6.662

– Juchli L. (2021). Effectiveness of Massage Including Proximal Trigger Point Release for Plantar Fasciitis: a Case Report. International journal of therapeutic massage & bodywork, 14(2), 22–29.

– Podolsky, R., & Kalichman, L. (2015). Taping for plantar fasciitis. Journal of Back and Musculoskeletal Rehabilitation, 28(1), 1–6. https://doi.org/10.3233/bmr-140485

– Landorf, K. B., Keenan, A.-M., & Herbert, R. D. (2006). Effectiveness of foot orthoses to treat plantar fasciitis. Archives of Internal Medicine, 166(12), 1305. https://doi.org/10.1001/archinte.166.12.1305

– Kogler, G. F., Veer, F. B., Solomonidis, S. E., & Paul, J. P. (1999). The influence of medial and lateral placement of orthotic wedges on loading of the plantar aponeurosis. an in vitro study*. The Journal of Bone & Joint Surgery, 81(10), 1403–13. https://doi.org/10.2106/00004623-199910000-00005

– Rupareliya, D., Shukla, Y., Bhise, A., & Prabhakar, M. (2015). To study the effect of eccentric loading exercises of calf muscles in plantar fasciitis. an interventional study. Physiotherapy, 101. https://doi.org/10.1016/j.physio.2015.03.1223

– Digiovanni, B. F., Nawoczenski, D. A., Malay, D. P., Graci, P. A., Williams, T. T., Wilding, G. E., & Baumhauer, J. F. (2006). Plantar fascia-specific stretching exercise improves outcomes in patients with chronic plantar fasciitis. A prospective clinical trial with two-year follow-up. The Journal of bone and joint surgery. American volume, 88(8), 1775–1781. https://doi.org/10.2106/JBJS.E.01281

 

Blog written by Tess Koparan