Painful symptoms accompanyingflexible flatfoot include, a wide distribution of pain and an increase infatigue rate in lower limb area, osteoarthritis, achilles tendinopathy andpatellofemoral disorders may appear. Other signs observed include the abnormalappearance of rearfoot kinematics such as a rearfoot excessive eversion or byan increase in the eversion range, abnormal kinetics of the foot and ankle suchas joint moments elevated or loading forces abnormal values and change in thephysical function by abnormal timing and activation of muscles or by raising consumptionof energy. These functional consequences are the reason for the symptomaticflexible flatfoot, and the intervention should target these abnormalities.(Banwell et al., 2014)In adult acquired ?atfoot, the deformityis due to arthritic changes, neuromuscular diseases, and traumatic conditions.While the most common deformity cause remains posterior tibial tendondysfunction, many conditions could cause the tendon dysfunction such as ruptureand secondary arthritis which is considered the most severe sequelae, in the U.
S.about 5 million people are affected by this condition.(Abousayed et al., 2016) Adult acquired flatfoot can becaused by many conditions such as, ankle degeneration changes that happen inthe tarsometatarsal or talonavicular or both, these degenerations occursecondary to fractures, inflammatory arthropathy and Osteoarthropathy. the Neuropathicfoot that occur secondary to leprosy, diabetes mellitus and profound peripheralneuritis. Loss of support at the medial longitudinal arch seen in tibialisposterior tendon dysfunction or calcaneoanvicular ligament tear. Otherconditions for painful flatfoot may include tarsal coalition.
Risk factorsinclude middle-aged women, hypertension, diabetes mellitus, injecting the areaaround the tendon with steroid, and seronegative arthropathies. These factorsare observed in the tibialis posterior tendon insufficiency condition.(Kohls-Gatzoulis et al.
, 2004)In flexible flatfoot etiopathologythis study indicated, while the normal medial longitudinal arch of the foot isformed by the foot bones which are supported by ligaments, tendon and capsularstructures, the medial longitudinal arch is not preserved by the foot muscles.The electromyographic study resulted in that intrinsic and extrinsic musclesdidn’t help in supporting or maintain the medial longitudinal arch whileassuming a standing position (Basmajian and Stecko, 1963). although during walking the dynamic stabilization of the arch ismaintained by both muscle groups, this argument is reinforced by a study thatresulted in that intrinsic muscles of the foot have an important role insupporting the medial longitudinal arch (Fiolkowski et al., 2003). In the posterior tibial tendon insufficiency flatfoot, it hasbeen suggested the musculature importance, as indicated in a study whichresulted that the most significant anatomical structure is the plantar fasciadue to its role in stability of the medial arch, along with the talonavicular,and spring ligaments.(Huang et al., 1993) In adult, flexible flatfoot mayappear bilateral or unilateral, the main symptoms are pain at arch, heel, andthe foot lateral aspect, these symptoms are aggravated by activities thatinclude weight bearing such as running, walking, and hiking. Orthotics isconsidered to be an early treatment option for this condition(Lee et al.
, 2005), its designed to stabilize and realign the foot arch, symptomsrelief is a noticeable success in patient.(Chen et al., 2010)In a search of the biomechanical effects of wearing footorthotics on medial longitudinal arch in patient with flexible flatfoot fromthe literature, one study compared between the effect of short foot exercisesand the use of insoles on the medial arch, in the orthotic group the orthotic was made to affect themedial arch height (value of 20° and a height of at least 15 mm) and wasstandard for all patient. The parameters assessed was measuring the changes inthe height of the medial longitudinal arch, which resulted in that short footexercises are more effective and insole changes in the medial longitudinal archwere not significant. The limitation of this study includes the sample size wassmall 14 (males 10, females 4), the period of the intervention is short (sixweeks) which is not sufficient for insoles to make an effect on the medial archor evaluate long-term effect. (Kim and Kim, 2016)While in this study they evaluatedthe effect of orthotics in different walking conditions, it was conducted for 3months, the shoe and orthotics werestandard for all patients, the orthotic measurement was (thickness arch 2.6 cm,and the thickness of fore foot and heel was 0.
4 cm), the parameters assessedwere the load rate and contactarea from planter pressure, the study resulted in an increase in the height offoot arch and there was a change from midfoot in weight-bearing to heel andfore foot, which lead to decrease in the midfoot contact area and load rate.The correction of planter pressure was found in horizontal ground and inwalking up and down stairs. The limitations include the sample size was small 15, they didn’t measure the changesin the arch height.
(Zhai et al., 2016)Anotherstudy compared the prefabricated and proprioceptive foot orthoses effect duringwalking on the distribution of plantar pressure, inthe prefabricated orthoticgroup the orthotic supported thelongitudinal arch and was 1-mm-thick while the proprioceptive orthotic group theorthotic was a flat with no arch support. The parameters assessed were peak pressure, maximum force, andcontact area, it resulted in the prefabricated insole there was no majordifferences in contact area, while a significant decrease in peak pressure andforce was noted, this reduction of the heel pressure is due to structuralmechanisms of supporting the medial arch that lead to load transfer intomidfoot area and in realigning the calcaneus to be in a normal position, thusleading to changes in pressure distribution. The limitations include thesample size is small 12 and theywere male only, they assessed it in walking condition, the study didn’t evaluatelong-term effect.(Aminian et al., 2013) Masamitsu Kidoa study evaluated theload response in medial arch to assess the effectiveness of the insoles in supportingthe medial arch, they used two types of insoles accessory insoles and therapeuticinsole which raised the arch by 10 mm with a 5-mm inner wedge, the parametersassessed include the load response, it resulted in that it was significant thatthe therapeutic insole suppressed talocalcaneal joint eversion compered to theaccessory insole, limitationsinclude the sample size is small 8 (males 4, females 4), they assessed it in mimicking a standing condition, the study didn’tevaluate long term effect. In Hassan Saeedi study, theyevaluated the effect of a customized orthoses done by University of CaliforniaBerkeley Laboratory and its impact on muscle activity and kinetic, the parametersassessed were Foot skeletal alignment, visual analog scale, muscle activity(tibialis anterior, peroneus longus and medial gastrocnemius), ground reactionforce.
The study resulted in there was a correction in the alignment of the foot,the VAS results were reduced, the foot is functioning with a less load on thesoft tissue, the limitationsinclude they only used one subject in the study, it was for one month henceno long-term effect can be given.(Saeedi et al., 2014)After reviewing these study resultsin the matter of orthosis effect on the medial arch, we can observe that thereis a need in increasing the sample number, and in investigating the long-termeffect of orthosis and measurement of the arch height which leads to theconclusion of the medial arch in flexible flatfoot to be realigned.