Plantar Pressure Analysis of Children with Hypermobile Ehlers-Danlos Syndrome During Gait

Ehlers-Danlos Syndrome (EDS) is a heritable genetic disorder that causes the collagen in connective tissue to be fragile and elastic. The prevalence of EDS is one in every 5,000 to 10,000 people worldwide. Hypermobile EDS (hEDS) is a common subtype of EDS that includes symptoms such as pain, hyperflexible joints and frequent dislocations. Those symptoms can lead to abnormal walking, poor balance, and osteoarthritis. Adults with hEDS have been shown to have specific plantar (foot) pressure patterns which cause pain and excessive fatigue during walking. There are limited studies that quantify plantar pressure in children with hEDS. Therefore, we used a Novel EMED system to collect plantar pressure data from eight subjects (12.2±5.4 years; range 9-17 years). The subjects walked at a self-selected speed across a 4-meter walkway with an imbedded pressure platform. For each subject, five steps of the dominant foot were analyzed by dividing each foot into ten regions plus the total foot according to the Peter Richard Cavanagh (PRC) mask. For each region, means were calculated for parameters of foot pressure, force, area, and time of contact. A Z-test was used to compare the children with hEDS to healthy individuals from a Novel database. Children with hEDS showed a statistically significant increase in peak pressure and mean pressure, respectively, for the medial forefoot (p=0.0165, p=0.0199), medial hindfoot (p=0.003, p=0.001), and total foot (p=0.0207, p\u3c0.001) regions. For eight of the regions there was significantly less contact area (p\u3c0.05) and not a significant difference in maximum force. Therefore, future therapeutic strategies should consider increasing the contact area and redistributing pressures, which may ultimately lead to a decrease in foot pain. These findings enhance our understanding of hEDS and improve diagnosis by contributing to the biomedical phenotype of this rare disease