Effectiveness of different foot orthotic designs on the foot kinematics and plantar loading of patients with hallux limitus

During dynamic activities, the first ray and first metatarsophalangeal joint occupy a critical role since both joints provide power absorption and generation. A first ray and or first metatarsophalangeal joint with limited mobility and pain during ambulation is known as hallux limitus. Functional hallux limitus occurs during walking and it is a condtion in which the proximal phalanx of the hallux is unable to rotate over the first metatarsal while the person is walking. Between 35-60 % of the population over 50 years have hallux limitus. When the mechanic and energetic features of both joints are affected, so-called (mal)adaptive compensations may manifest including: alterations of the sagittal plane ankle, hip and midtarsal joint kinematics, alterations of the plantar pressure distribution and the footprogression angle. There are both invasive and non-invasive treatment options in order to manage this painful foot condition. The conservative treatment typically encompasses the application of foot orthoses with specific features or so-called add-ons (e.g. kinetic wedge or cut out, wedges) together with rocker shoes. Critical appraisal of the literature highlights that there is poor evidence about the effectiveness of these foot orthoses in changing the aforementioned compensations, hence, this may explain the suboptimal outcome reported in some studies. As a consequence, the doctoral candidate will investigate through a randomized controlled trial the biomechanical and clinical effect of different foot orthoses in patients with hallux limitus.