Biomechanical Analysis of Achilles Tendon Stretch And Plantar Fascia Stretch In Plantar Fasciitis Treatment

Abstract

Abstract. This paper aims to simulate two stretching methods adopted in plantar fasciitis treatment in MSC.ADAMS, Achilles tendon stretch and plantar fascia stretch. Clinical evidence has been accumulated that stretching is effective in relieving heel pain caused by plantar fasciitis. While plantar fascia stretching is conceived to be more effective than the traditional Achilles tendon stretch, the reason leading to this difference has not been identified yet. A multi-segment foot model consisted of ligaments, plantar fascia, plantar soft tissue was constructed and then validated by comparing the ground reaction forces and joint rotation angles obtained in a gait simulation with previous research results. The model was then applied in finding out the root cause in these two stretching methods by analysing the deformation of plantar fascia. Achilles tendon stretch was performed to collect kinematic data of tibia using NDI, which was used to drive the simulation. In the plantar fascia stretch, a rotational plate was placed beneath the fore-foot and had a range of motion from 0° to 20°. The forefoot was supported and lifted to simulate the stretching process. Deformation of the plantar fascia under two stretching methods were compared. The result shows that average deformation in Achilles tendon is smaller than that of plantar fascia stretch which may cause the therapeutic difference between these two stretch methods. This analysis method could also be applied in refining physical therapy treatment.