Plantar Fasciitis is a common overuse condition affecting many runners in Boulder. Authors report it is the 3rd most common running related injury and total costs involving plantar fasciitis cost over 375 million dollars per year (Taunton et al. 2002). Much of these costs can be attributed to the chronic nature of the condition reaching up to 12 months in some individuals. Treatment by a Physical Therapist involving manual therapy to the lower quarter joints and strengthening exercises have been shown to accelerate recovery and shorten this duration of symptoms.
The plantar fascia is a passive restraint to forces across the foot and ankle when we stand or weight bear on one foot. In addition to the plantar fascia we are able to use hip and leg muscles, muscles crossing the ankle, and intrinsic foot muscles, deep in the foot, to absorb these running forces. Commonly in patients with plantar fasciitis we find reduced strength and balance throughout the leg. A key element to successful treatment of plantar fasciitis involves restoring both global strength in the leg and local strength in the foot to reduce abnormal loading patterns across the heel and arch of the foot.
A recent article examined the size of the intrinsic foot muscles in experienced runners with and without plantar fasciitis (Cheung et al. J Sci Med Sport. 2015). 10 of the 20 runners were diagnosed with chronic heel pain (>2 years) while the others served as a control group. The authors noted atrophy of the intrinsic foot musculature in the runners with plantar fasciitis. We are not able to determine cause and effect in this study design but this indicates the importance of intrinsic foot strengthening in patients’ with heel pain. The stronger these muscles become the better their tolerance to control forces across the foot in running. In turn, less forces will be applied to the passive elements of the foot like the plantar fascia.