Overview
The plantar fascia is a thick tissue that stretches along the bottom of the foot from the heel bone towards the toes, with some of the fibers close to the skin. It provides support for the foot and helps to maintain the dynamic alignment of the foot and leg while walking and running. Overuse and repetitive microtrauma cause inflammation and degeneration of these fibers. When this tissue becomes painful and stiff, it is described as plantar fasciitis.
Risk Factors
In the general population, increased risk is seen with obesity, heel spurs, poor strength and flexibility, and prolonged standing. In athletes, especially runners, there is increased risk with flat feet, high-arched feet, limited ankle flexibility (from tight Achilles tendons), incorrect running shoe fit, inadequate warm-up, and excessive training (especially with sudden increases in distance).
Symptoms and Signs
Patients with plantar fasciitis describe sharp pain on the plantar aspect (bottom) of the foot. It is worse when first starting to walk after sitting or lying down, especially when first getting out of bed in the morning. The symptoms usually get worse at the beginning of a workout, but improve with time. On exam, there is usually a discrete area that is tender to touch over the medial part of the heel bone. The discomfort, however, can extend over the length of the fibers down the foot. Limited big toe extension is often seen with plantar fascial tightness.
Treatment
Although the symptoms frequently improve with conservative management, chronic plantar fasciitis may develop. For this reason, it is important that the initial management addresses both the symptoms and the mechanical factors that potentiate it. Initial therapy includes protection with activity modification. Low impact exercise while avoiding activities that exacerbate the pain is recommended. Ice massage, especially after activity or at the end of the day may be helpful. Anti-inflammatory medications may be used for a brief course if there is a suspected inflammatory component. Arch support with taping and/or the use of heel cups has been helpful in some patients. The use of custom orthotics is controversial, though helpful for some patients. When there is continued pain, despite conservative treatment, short-term relief may be seen with injection of a cortiocosteroid and anesthetic into the painful region. Only rarely has surgery been used to release the plantar fascia.
Complications
Most pain resolves with conservative management. Patients with chronic pain may develop a limp which predisposes them to other back and knee symptoms. Athletes often try to “run through” their symptoms, which may cause degeneration and damage of the plantar fascia. Repeated injections, during the course of treatment, can lead to scarring and tearing. Surgery can cause pain or weakness of the foot during push-off.
Prevention
It is unknown if certain stretches, exercises or training regimens specifically prevent plantar fasciitis. Appropriate footwear, in addition to a comprehensive fitness program that includes strength and strengthening are recommended for overall health and injury prevention.
References
1) Frontera et al., Essentials of Physical Medicine and Rehabilitation, 2002, p. 444.
2) Safran el al., Instructions for Sports Medicine Patients, 2003, p576.
3) UpToDate, www.uptodate.com