# Pedobarography: A Review on Methods and Practical Use in Foot Disorders
## 4 Discussion
### Difficulties and Ambiguities concerning Pedobarography  
A pedobarography system is a complex computerized setup equipped with pricey sensors. For instance, the F-Scan System has sensitive in-soles whose structure is based on load-sensitive resistive membranes (force-sensing resistor--FSR). These sensors last for approximately 30 gait cycles [55; 56]. The pressure exerted on the boundary of FSR increases the output and shortens the sensor's lifetime. To extend the durability of sensors, improvements must be made to the insole to protect the sensor's edge [39]. Another drawback of the embedded sensors is that the footwear itself may modify the measurement [57; 58]. While walking barefoot, the pressures are higher in the metatarsal, hindfoot, and lateral part of the forefoot with lower pressures observed under the toes, compared to the test performed in the shoes [59]. [PERSON] et al. [60] has also reported that the pressure distribution varies depending on the type of insoles and shoes. To minimize the distortion of results caused by the footwear, pedobarography should be best performed using two different types of footwear [27]. A solution to this problem could be to use the Pedar-X in-sole system inside the anti-skid socks to minimize the influence of footwear on the plantar pressure [61]. Pedobarography is a tedious and time-consuming method, which rules out its standard use in the clinic. The tests must be preceded by instructive, often numerous training trials. Additionally, the in-soles are calibrated according to the manufacturer's instructions and the zero-setting procedure is required before data acquisition. The average time required for a dynamic pedobarography examination using the in-shoe system is 25 min [27]. A disadvantage of pedobarography for diagnostic use lies in a variety of plantar regional divisions. For instance, [PERSON] et al. [54] have distinguished the following regions: anterior masks (1 st-5 th toes and 1 st-5 th metataralsals), posterior masks (medial heel and lateral heel), medial masks (medial heel, 1 st metataralsal, and 1 st toe), and the lateral masks (lateral heel, 2 nd-5 th metataralsals, and 2 nd-5 th toes). The classification proposed by [PERSON] [62] is a modification of [PERSON] and [PERSON]'s [17] by adding a T region between hind-foot and mid-foot. Different plantar divisions point to the lack of a consensual classification and make the comparison of various tests unreliable in the diagnostics of foot pathologies. Difficulties in the evaluation of dynamic pedobarography are usually caused by over-emphasizing one of the gait phases, especially the stance phase. Consequently, to the excessive patient's concentration on this phase, the maximum pressure in the hindfoot region becomes higher, which hinders the interpretation of results while walking. [PERSON] et al. [63] have noticed that the gait velocity may increase pressures arising in the heel and forefoot regions. Dynamic pedobarography is particularly difficult to perform in pre-school children who despite correctly designated starting slide and repeated trials, often bypass the platform or step partway on it [64]. [PERSON] et al. [51] and [PERSON] et al. [53] have contended that the platform surface should be covered with an overlayer of ethylene-vinyl acetate (EVA) to ensure that the patient is unaware of the measurement time. The diagnostic pedobarography is also hindered by plantar pressure differences in the same patient during an examination. The variability is due mainly to the functional state of the musculoskeletal system but may also be caused by disparities in whole-body movements [65]. [PERSON] et al. [66] and [PERSON] [67] have demonstrated that joint stiffness is responsible for higher foot pressures while walking. However, [PERSON] et al. [47] point out that structural characteristics account for only about one-third of the variability observed in healthy people during dynamic pedobarography.