Custom-made foot orthoses with and without heel plugs and their effect on treatment outcomes and plantar pressures in patients with plantar fasciitis: A crossover study

Background: Plantar fasciitis (PF) is considered to be the most common cause of plantar heel pain in adults. Various types of foot orthoses (FOs) have been used to treat plantar heel pain, between flat ethylene-vinyl acetate (EVA) devices, to prefabricated orthoses, to completely custom FOs. The objective of this crossover study was to quantify both objective plantar pressures, and subjective foot function and comfort ratings for two custom foot orthoses (CFOs), one with a heel plug (HP) and one without. Methods: Twenty-one patients with diagnosed PF participated in this study and were casted using a semi–weight-bearing foam box cast. Both CFOs were made with the same materials and specifications, but the HP orthosis had a softer blue PORON ® plug under the heel for added cushioning. The foot function index (FFI) was given at weeks 0, 4, and 8, as well as a subjective comfort rating at 4 and 8 weeks. Plantar pressures were recorded during treadmill walking for both devices in a running shoe after 8 weeks, after having worn each pair for 4 weeks. Average pressure, peak pressure, and pressure contact area were determined for 3 regions of the foot: hindfoot, midfoot, and forefoot. A paired samples t test determined differences in each region. Results: Average pressure, peak pressure, and pressure contact area were significantly reduced at the hindfoot in the HP orthosis ( P < 0.001), and peak pressure was significantly reduced at the midfoot with the HP orthosis ( P < 0.05). Total FFI scores were significantly reduced with both orthosis types compared to baseline ( P < 0.01), but there was no difference in FFI scores or comfort scores between CFO conditions. Conclusions: CFOs with heel plugs are more effective at reducing plantar pressure at the heel in patients with PF compared to CFOs without heel plugs. Both CFOs were effective at reducing FFI scores, showing an improvement in pain, and an increase in function and activity after both 4 and 8 weeks of treatment.