High Plantar Pressure Research Articles

Could Insoles Offload Pressure? An Evaluation of the Effects of Arch-supported Functional Insoles on Plantar Pressure Distribution during Race Walking

This study investigated the effectiveness of functional insoles on plantar pressure distribution during race walking so as to reduce the high plantar pressure and force on race walkers, who tend to suffer from overuse injury. A total of 20 male race walkers aged 21.19 ± 3.66 years and with a mean height of 178.85 ± 14.07 cm were recruited as participants. Each participant completed a race walking with functional or normal insoles. Plantar pressure insoles were used to collect vertical plantar pressure data. A two-way analysis of variance with a mixed design was used to determine the difference between the two conditions. Results showed that the use of functional insoles reduces the peak pressure and the impulse in the metatarsophalangeal joints and heels and thus suggest that functional insoles reduce the overuse injury risks of these parts. The first ground reaction force peak also decreased. This result suggested that functional insoles reduce the risks of foot and leg injuries.

Diabetic Foot and Footwear

Diabetes mellitus is one of the most common diseases around the world, and mainly affects the foot among the human body parts. The main causes of the diabetic foot are neuropathy, peripheral arterial disease and foot deformities; it leads to foot ulceration. Generally, sensory loss, high plantar pressure, foot deformities, inappropriate footwear, blindness, and age are the causing risk factors for developing foot ulceration in diabetic patients. Foot ulceration will result in prolonged hospitalization, high medical expenses, and serious complications with lower extremity amputation. For a long time, appropriate footwear has been recommended by physicians for reducing plantar pressure to prevent foot ulceration, the risk of amputation, and re-ulceration. A review is provided in this article towards the existing literature on the causes and prevalence of the diabetic foot, foot ulceration, off-loading pressure, footwear modification for different types of diabetic foot deformities, and types of footwear and textile materials used in footwear insoles for healing purposes.

New methodology for a correct gait

A proper biomechanics of the foot is fundamental for the maintenance of posture and for a symmetrical distribution of plantar pressures. It ‘been shown that high plantar pressures are greater risks of damage to be covered by the same foot that the anatomical structures involved in the above processes postural(1). Thus numerous studies have investigated the effectiveness of orthotics that, by increasing the contact surface between the foot and the ground, they were going to decrease the load associated with certain anatomical districts(2). The aim of our study was to evaluate, through static and dynamic baropodometry, the effectiveness of the regular gait, a new support that has the task of stabilizing the arch of the foot in static and to allow proper movement of the same. These subjects underwent rating scales and baropodometric examination before and after using the orthotics. It was carried out both the analysis monopodalic, for the evaluation of the effectiveness of the insole in the redistribution of pressures between different zones of a same foot, both the bipodalic for the evaluation of the symmetry in the distribution of the pressures between the different feet. The results obtained, subjected to statistical analysis for significance, show that the insole, to how it was designed, is able to restore a correct distribution of the parameters both in analysis monopodalic that bipodalic and both in static and dynamic conditions. These redistributions, in addition, also remain in the tests posttreatment without footwear, showing that the particular conformation of the plantar, with supports positioned in specific districts of the arch of the foot, is able to stimulate the proprioceptors present therein and therefore to enable a reorganization at the central level . This reorganization allows the subject treated with the regular gait to maintain the morphology and the smooth running of the propeller breech during movement not only while wearing the insole, but also after it has been removed

Human Plantar Pressure Image and Foot Shape Matching

Medical doctors and podiatrists have been using plantar pressure for the evaluation of the foot loading in regard to foot biomechanics and foot health for decades. High plantar pressure can cause pain and foot injury such as plantar ulcer during walking. Two types of systems are suitable for pressure capture and they are commonly known as floor mat or floor pad and in-shoe pad. For the floor-mat system pressure values are displayed as image which does not depict the foot shape. Therefore, shortcoming of this system for plantar pressure recording during walking is that the location of the pressure value related to the plantar surface is only approximate. A research was conducted to determine whether markers can be placed on the plantar surface and their positions identifiable on the pressure image. This paper describes the technique for matching the plantar shape to the pressure image during walking.

Prospective Evaluation of Leprosy Patients Wearing Insole

The use of custom-made insoles has shown to be effective for the treatment of high plantar pressure peak of patients with neuropathic feet. Objective: To observe the results of the usage of metatarsal plantar support type of insole in leprosy, through tests in gait and static posture with a baropodometric device. Ten patients diagnosed with leprosy were randomly selected, ageing 25 to 60 years in drug treatment at the Ribeirão Preto Medical School Clinical Hospital, University of São Paulo (CRNDS-HCFMRP-USP), were they were asked to stand in a static position and then to walk on the Baropodometer (Footwork-ISP). Pressure peaks were observed in 7 predefined plantar areas during standing position, and plantar contact time was observed during gait. Next, a custom-made insole was installed into the patient’s footwear, according to the Brazilian Ministry of Health. The above assessment was redone after 10 months of continuous insole usage. The collected data was compared and statistically analyzed, revealing that the 7 plantar areas did not show significant differences for pressure peaks recorded before and after the use of insoles during standing position. The dynamic analysis, however, showed a significant reduction in plantar contact time, meaning a faster gait of these patients after the use of insoles. We conclude that the metatarsal plantar support type of insoles improve the dynamic balance of patients, but did not modify the foot’s pressure distribution.

Kinematics and kinetics of single-limb heel rise in diabetes related medial column foot deformity

BackgroundDiabetes-related medial column foot deformities contribute to high plantar pressure, joint instability, ulceration and amputation. Impaired foot function may be an early indicator of foot structural incompetence and contribute to deformity progression. This study examines the ability of single-limb heel rise multi-segmental kinematics and kinetics to identify midfoot and hindfoot dysfunction in those with diabetes-related medial column foot deformity. MethodsSingle-limb heel rise foot kinematics and kinetics were examined in adults with diabetes mellitus and peripheral neuropathy with and without medial column foot deformity and age-, weight-matched controls. FindingsHindfoot relative to shank plantarflexion, peak and excursion, were reduced in both diabetes groups compared to controls (P<0.017). Controls' initial forefoot relative to hindfoot position was plantarflexed 31° and plantarflexed an additional 13° during heel rise. The initial forefoot relative to hindfoot position for the diabetes group without deformity was similarly plantarflexed as controls (34°) while the diabetes deformity group was less plantarflexed (lower arch position: 23°, P<0.017). During the heel rise task both diabetes groups demonstrated less ability to plantarflex the forefoot relative to the hindfoot compared to controls (2 and 5° respectively, P<0.017). Ankle plantarflexion power was reduced in the diabetes deformity group compared to controls (P<0.017). InterpretationThe single-limb heel rise task identified movement dysfunction in those with diabetes mellitus and peripheral neuropathy. Failure to plantarflex the forefoot relative to hindfoot may compromise midfoot joint stability and increase the risk of injury and arch collapse.

Baropodometric examination of patients with diabetic neuropathy at 2 years follow-up: Identification of kinematic parameters of gait related to neuropathy progression

Introduction: The incidence of “diabetic foot” in the population affected is well known. Recent epidemiological studies show that the 8% of deaths, related to diabetes, is the direct consequence of leg ulcers [1] and that the survival after major amputation is less than 50% at 5 years after surgery [2]. The high plantar pressure has been associated prospectively to the development of ulcers in diabetic patients, and would be strongly predictive for it [3]. The aim of this study is the evaluation of plantar property in orthostatic position and during the gait in diabetic patients with and without neuropathy. Correlation between the kinematic parameters – measured by baropodometric platform – and patient’s neuropathy stage are statistically evaluated. Methods: The study is based on a cluster of 24 patients (15 malesand9 females), divided into three subgroups, according to the stage of neuropathy, following the Dyck’s scale (1993), and compared with 18 healthy controls (10males and 8 females). The same cluster is examined 2 years later. After an initial physical examination, patients were subjected to an instrumental gait analysis by baropodometric platform. The study uses an experimental scheme consists of a static test, during which the patient remains upright andmotionless for 10 s, and a dynamic test, which allows to obtain informations about the pressure, the area and the duration of support during the gait. Parameters normalizationwas applied in order to increase statistical significance Results: The kinematic data highlights that integral pressuretime is better thanpeakpressure value towhicha certain areaof the foot is subjected. Regarding the peak pressure, emerged an increase of the mean value, by comparing groups without neuropathy to those with neuropathy. The duration of support has proved to be highly significant in distinguishing membership in different stages of neuropathy (p=0.0014). The dynamic analysis shows a decrease of the support area related to the progression of neuropathy, as well as moving from controls to the patients without neuropathy. Static analysis revealed that the progression of neuropathy causes an instability even when standing still, as deduced from a stabilometric study. The follow-up analysis shows that the duration of support represents the parameter most changeable over time, in the same patient (p=0.0692). Discussion: The average values support a correlation with the progression of neuropathy. The increase of the peak pressure, in literature, was already relatedwith the neuropathy development and with an higher risk of plantar ulcers. The obtained results support the theory that a follow-up baropodometric is useful in monitoring the progression of neuropathy in diabetic patients. The data obtained may be a valid parameters for prevention, rehabilitation and motor re-education for getting and maintaining a more corrected gait.

Influência da distância de corrida na pressão plantar

Running is a popular sport performed at different places and involving different distances and modalities. Long distance running promotes cumulative loading on joints and soft tissues that could determine important biomechanical alterations. A tool for assessing such loads is the measurement of plantar pressure. Here we compared static plantar pressure before and after 10 km and 21 km running competitions. Twenty trained runners participated in this study. They were assigned to 10 km (n=10) or 21 km (n=10) group according to their competition distance. Static plantar pressure was assessed in the day before competition and quickly after competition finished. Mean plantar pressure was compared between pre and post competition, between groups, legs and foot regions. Static plantar pressure did not differ between feet in either groups. In 10 km runners, higher plantar pressure post competition was observed in the forefoot, while any changes were observed in the 21 km group. Differences in plantar pressure between foot regions were similar between groups. In summary, static assessment of plantar pressure seemed more sensitive to changes in plantar pressure after a 10 km running, but not after 21 km. After 10 km running, forefoot experiences higher plantar pressure.

Simple finite element models for use in the design of therapeutic footwear

Therapeutic footwear is frequently prescribed in cases of rheumatoid arthritis and diabetes to relieve or redistribute high plantar pressures in the region of the metatarsal heads. Few guidelines exist as to how these interventions should be designed and what effect such interventions actually have on the plantar pressure distribution. Finite element analysis has the potential to assist in the design process by refining a given intervention or identifying an optimal intervention without having to actually build and test each condition. However, complete and detailed foot models based on medical image segmentation have proven time consuming to build and computationally expensive to solve, hindering their utility in practice. Therefore, the goal of the current work was to determine if a simplified patient-specific model could be used to assist in the design of foot orthoses to reduce the plantar pressure in the metatarsal head region. The approach is illustrated by a case study of a diabetic patient experiencing high pressures and pain over the fifth metatarsal head. The simple foot model was initially calibrated by adjusting the individual loads on the metatarsals to approximate measured peak plantar pressure distributions in the barefoot condition to within 3%. This loading was used in various shod conditions to identify an effective orthosis. Model results for metatarsal pads were considerably higher than measured values but predictions for uniform surfaces were generally within 16% of measured values. The approach enabled virtual prototyping of the orthoses, identifying the most favorable approach to redistribute the patient’s plantar pressures.

Elevated plantar pressure in diabetic patients and its relationship with their gait features

PurposeHigh plantar pressure is a major risk factor for diabetic foot ulcers. The relationship between plantar pressure and foot mobility has been investigated in some studies. However, when the foot is in motion, foot mobility is only a small feature of the gait. Therefore, we investigated relationship between high plantar pressure and gait and also studied the motion of the trunk. In addition, we investigated the relationship between gait and patient characteristics to identify patients at high-risk of developing diabetic foot ulcers. MethodsThe relationships between elevated plantar pressure, gait features, and patient characteristics were analyzed. Plantar pressure distribution in the stance phase was divided on the four plantar segments. Elevated plantar pressure was defined as being more than the mean plus one standard deviation of the corresponding segment in non-diabetic subjects. Plantar pressure distribution was measured by an F-scan system, and gait features were measured using wireless motion sensors attached to the sacrum and feet. Patient characteristics were obtained from medical records or by interview. ResultsSmall roll and yaw motions of the body and yaw motion of the foot during the mid-stance phase were related to the elevated plantar pressure in 57 diabetic patients. Furthermore, these gait features were related to sensory neuropathy, diabetes duration, patient weight, toe-gap force, and ankle range of motion. ConclusionGiven our findings, it may be possible to prevent diabetic foot ulcers by increasing foot motion during the mid-stance phase. Passive exercise aimed at expanding ankle range of motion in patients with sensory neuropathy or long-standing diabetes may assist in achieving this.

Baropodometric Evaluations and Sensitivity Alterations in Plantar Ulcer Formation in Leprosy

Leprosy is a chronically evolving granulomatous disease caused by the bacillus Mycobacterium leprae, which exhibits tropism for peripheral and motor nerves and slow-growing inflammation that affects the peripheral nervous system, especially the sensory fibers. The aim of this study was to observe the relationship between peak pressure and abnormal sensitivity for the formation of plantar ulcers in patients with multibacillary (MB) and paucibacillary (PB) leprosy. A total of 51 individuals with leprosy were evaluated and classified as either MB or PB and then submitted to the Semmes-Weinstein sensitivity test; 20 normal individuals were examined as a control group and took a baropodometric test. The pressure peaks and sensitivity alterations were noted and compared within groups. Leprosy patients exhibited a greater loss of sensitivity at the heel area that might compromise gait. During dynamic analysis, the MB group with altered sensitivity for right and left feet and PB (left feet) group showed the highest plantar pressure values. Skin damage (calluses or ulcers) did not occur within the areas of high plantar pressure in 80% of MB patients, whereas skin damage was observed in 38% of PB patients in the areas of higher peak pressures. According to these findings, baropodometry and sensitivity tests play an important role in the understanding of ulcer biodynamics. In addition, it could be inferred that the loss of protective sensibility in MB patients is predictive of plantar ulcers, whereas plantar pressure peaks seem to be of greater importance in PB patients.

Effect of medial arch support foot orthosis on plantar pressure distribution in females with mild-to-moderate hallux valgus after one month of follow-up

Higher plantar pressures at the medial forefoot are reported in hallux valgus. Foot orthoses with medial arch support are considered as an intervention in this pathology. However, little is known about the effect of foot orthoses on plantar pressure distribution in hallux valgus. To investigate the effect of a foot orthosis with medial arch support on pressure distribution in females with mild-to-moderate hallux valgus. Quasi-experimental. Sixteen female volunteers with mild-to-moderate hallux valgus participated in this study and used a medial arch support foot orthosis for 4 weeks. Plantar pressure for each participant was assessed using the Pedar-X(®) in-shoe system in four conditions including shoe-only and foot orthosis before and after the intervention. The use of the foot orthosis for 1 month led to a decrease in peak pressure and maximum force under the hallux, first metatarsal, and metatarsals 3-5 (p < 0.05). In the medial midfoot region, peak pressure, maximum force, and contact area were significantly higher with the foot orthosis than shoe-only before and after the intervention (p = 0.00). A foot orthosis with medial arch support could reduce pressure beneath the hallux and the first metatarsal head by transferring the load to the other regions. It would appear that this type of foot orthosis can be an effective method of intervention in this pathology. Findings of this study will improve the clinical knowledge about the effect of the medial arch support foot orthosis used on plantar pressure distribution in hallux valgus pathology.

Choice of wound care in diabetic foot ulcer: A practical approach.

Diabetic foot ulcers are the consequence of multiple factors including peripheral neuropathy, decreased blood supply, high plantar pressures, etc., and pose a significant risk for morbidity, limb loss and mortality. The critical aspects of the wound healing mechanism and host physiological status in patients with diabetes necessitate the selection of an appropriate treatment strategy based on the complexity and type of wound. In addition to systemic antibiotics and surgical intervention, wound care is considered to be an important component of diabetic foot ulcer management. This article will focus on the use of different wound care materials in diabetic foot. From a clinical perspective, it is important to decide on the wound care material depending on the type and grade of the ulcer. This article will also provide clinicians with a simple approach to the choice of wound care materials in diabetic foot ulcer.

Effect of arch type and Body Mass Index on plantar pressure distribution during stance phase of gait.

Several factors have been associated with the presence of abnormally high plantar foot pressure including: (i) increased body weight, (ii) foot structure and (iii) walking strategy. It is predicted that the biomechanics of the foot is influenced by the structure of the foot, primarily the Medial Longitudinal Arch. The objective of this study was to examine if Body Mass Index and the foot arch have a direct effect on dynamic peak plantar pressure for healthy subjects. Following a clinical lower limb examination, the Tekscan HR mat was utilised for this study, plantar pressure was profiled at specific events during stance phase of gait including heel strike, midstance and toe off. Results indicated to the preferable normal arch as this produced a low plantar pressure distribution in all cases. The 2nd and 3rd metatarsal head region recorded the highest pressure for all arch types during dynamic analysis. The lowest pressure for the normal and overweight BMI was at toe-off. While the obese BMI group showed highest pressure during toe-off. The obese BMI flat arch subcategory indicated to functional ambulation differences. Future work involves comparing this healthy database to a demographically matched diabetic group.

Plantar pressure as a risk assessment tool for diabetic foot ulceration in egyptian patients with diabetes.

BACKGROUNDDiabetic foot ulceration is a preventable long-term complication of diabetes. In the present study, peak plantar pressures (PPP) and other characteristics were assessed in a group of 100 Egyptian patients with diabetes with or without neuropathy and foot ulcers. The aim was to study the relationship between plantar pressure (PP) and neuropathy with or without ulceration and trying to clarify the utility of pedobarography as an ulceration risk assessment tool in patients with diabetes.SUBJECTS AND METHODSA total of 100 patients having diabetes were selected. All patients had a comprehensive foot evaluation, including assessment for neuropathy using modified neuropathy disability score (MNDS), for peripheral vascular disease using ankle brachial index, and for dynamic foot pressures using the MAT system (Tekscan). The studied patients were grouped into: (1) diabetic control group (DC), which included 37 patients who had diabetes without neuropathy or ulceration and MNDS ≤2; (2) diabetic neuropathy group (DN), which included 33 patients who had diabetes with neuropathy and MNDS >2, without current or a history of ulceration; and (3) diabetic ulcer group (DU), which included 30 patients who had diabetes and current ulceration, seven of those patients also gave a history of ulceration.RESULTSPP parameters were significantly different between the studied groups, namely, forefoot peak plantar pressure (FFPPP), rearfoot peak plantar pressure (RFPPP), forefoot/rearfoot ratio (F/R), forefoot peak pressure gradient (FFPPG) rearfoot peak pressure gradient (RFPPG), and forefoot peak pressure gradient/rearfoot peak pressure gradient (FFPPG/RFPPG) (P < 0.05). FFPPP and F/R were significantly higher in the DU group compared to the DN and DC groups (P < 0.05), with no significant difference between DN and DC. FFPPG was significantly higher in the DU and DN groups compared to the DC group (P < 0.05). RFPPP and FFPPG/RFPPG were significantly higher in the DU and DN groups compared to the DC group (P < 0.05) with no significant difference between the DN and DU groups (P > 0.05). FFPPP, F/R ratio, FFPPG, and FFPPG/RFPPG correlated significantly with the severity of neuropathy according to MNDS (P < 0.05). These same variables as well as MNDS were also significantly higher in patients with foot deformity compared to those without deformity (P < 0.05). Using the receiver operating characteristic analysis, the optimal cut-point of PPP for ulceration risk, as determined by a balance of sensitivity, specificity, and accuracy was 335 kPa and was found at the forefoot. Multivariate logistical regression analysis for ulceration risk was statistically significant for duration of diabetes (odds ratio [OR] = 0.8), smoking (OR = 9.7), foot deformity (OR = 8.7), MNDS (OR = 1.5), 2-h postprandial plasma glucose (2 h-PPG) (OR = 0.9), glycated hemoglobin (HbA1c) (OR = 2.1), FFPPP (OR = 1.0), and FFPPG (OR = 1.0).CONCLUSIONIn conclusion, persons with diabetes having neuropathy and/or ulcers have elevated PPP. Risk of ulceration was highly associated with duration of diabetes, smoking, severity of neuropathy, glycemic control, and high PP variables especially the FFPPP, F/R, and FFPPG. We suggest a cut-point of 355 kPa for FFPPP to denote high risk for ulceration that would be more valid when used in conjunction with other contributory risk factors, namely, duration of diabetes, smoking, glycemic load, foot deformity, and severity of neuropathy.

The evolution of compliance in the human lateral mid-foot

Fossil evidence for longitudinal arches in the foot is frequently used to constrain the origins of terrestrial bipedality in human ancestors. This approach rests on the prevailing concept that human feet are unique in functioning with a relatively stiff lateral mid-foot, lacking the significant flexion and high plantar pressures present in non-human apes. This paradigm has stood for more than 70 years but has yet to be tested objectively with quantitative data. Herein, we show that plantar pressure records with elevated lateral mid-foot pressures occur frequently in healthy, habitually shod humans, with magnitudes in some individuals approaching absolute maxima across the foot. Furthermore, the same astonishing pressure range is present in bonobos and the orangutan (the most arboreal great ape), yielding overlap with human pressures. Thus, while the mean tendency of habitual mechanics of the mid-foot in healthy humans is indeed consistent with the traditional concept of the lateral mid-foot as a relatively rigid or stabilized structure, it is clear that lateral arch stabilization in humans is not obligate and is often transient. These findings suggest a level of detachment between foot stiffness during gait and osteological structure, hence fossilized bone morphology by itself may only provide a crude indication of mid-foot function in extinct hominins. Evidence for thick plantar tissues in Ardipithecus ramidus suggests that a human-like combination of active and passive modulation of foot compliance by soft tissues extends back into an arboreal context, supporting an arboreal origin of hominin bipedalism in compressive orthogrady. We propose that the musculoskeletal conformation of the modern human mid-foot evolved under selection for a functionally tuneable, rather than obligatory stiff structure.

Relationship Between Obesity and Plantar Pressure Distribution in Youths with Down Syndrome

This study aimed to characterize the effect of obesity on foot-ground contact in young individuals affected by Down syndrome (DS) during quiet upright stance. This is a cross-sectional study on 118 individuals with Down syndrome, 59 with obesity aged 3-18 yrs and 59 with normal weight, age- and sex-matched forming the control group. Both groups were evaluated while standing on a pressure-sensitive mat. Foot-ground contact was characterized using contact area and mean pressure calculated for the rearfoot, the midfoot, and the forefoot. The results show that obesity significantly influences the foot-ground interaction, with some differences related to sex. In particular, the females with obesity exhibited larger contact areas and higher plantar pressures (in the forefoot and the midfoot) with respect to the control group, whereas in the males with obesity, only the plantar pressures were found higher than those of the controls. Flatfoot is the prevalent arch type for both groups, but its incidence seems to be unrelated to obesity. The modifications introduced by obesity in foot-ground contact pressure and area may represent a factor capable of aggravating existing negative podiatric issues associated with Down syndrome. Thus, planning periodical monitoring of foot-ground contact during childhood and adolescence is recommended to avoid possible problems related to adverse effects of repeated excessive mechanical stresses on the plantar region.

Risk Factors Correlated with Plantar Pressure in Chinese Patients with Type 2 Diabetes

Plantar pressure is a key factor for predicting ulceration in the foot of a diabetes patient. We recruited a group of 100 Chinese patients with type 2 diabetes and an age-, sex-, weight-, and height-matched group of 100 Chinese subjects without diabetes. We obtained plantar pressure data using a Footscan(®) gait system (RsScan International, Olen, Belgium) when the subjects with and without diabetes walked barefoot across a sensor platform. We recorded the maximum force, maximum pressure, impulse, pressure-time integral, and loading rate from 10 regions of the foot. We collected the data of 11 history-based variables, 10 anthropometric variables, and three metabolic variables regarding the clinical characteristics of the diabetes patients. Weight was identified as a determining factor for high plantar pressure. Height, the Neuropathy Symptom Score (NSS), and ankle-brachial index (ABI) were correlated positively with plantar pressure measurements, respectively. The sex, history of ulcer and callus, intima-media membrane of the lower limb blood vessels, and fasting blood glucose (FBG) could also explain a portion of the variability of the plantar pressure measurements. However, the correlations were low or weak. High plantar pressure in diabetes patients could be predicted, in part, based on weight, height, NSS, ABI, sex, history of ulcer and callus, intima-media membrane of the lower limb blood vessels, and FBG. Therefore, interventions should be taken specifically before high plantar pressure emerges.

A comparison of plantar pressures in a standard flip-flop and a FitFlop using bespoke pressure insoles

Purpose: The study was undertaken to compare plantar pressures in a Havaiana flip-flop to a FitFlop, a flip-flop with a multi-density midsole designed to induce instability. It was hypothesised that in the Havaiana the toes are used to ‘grip’ the shoe in swing and the loose upper and thin sole provide limited protection to the foot, producing higher plantar pressures than the FitFlop. Methods: Twenty female subjects walked in the footwear conditions while a bespoke instrumented insole quantified plantar pressures. Data analysis grouped sensors into regions for the heel, 1st metatarsophalangeal joint and hallux to isolate pressures that have been linked to comfort and symptoms reportedly alleviated in the FitFlop. Additional analysis was undertaken to measure hallux ‘gripping’ during swing. Results: Significant reductions in plantar pressures in the FitFlop, particularly in peak pressure in the heel (3.6%) and pressure-time integral in the 1stmetatarsophalangeal joint (12.0%) were identified. These findings were attributed to the thicker midsole with different ethylene vinyl acetate (EVA) construction and a redistribution of load to the midfoot where contact area increased by 19.9% compared to the Havaiana. Also evident were reductions in anterior-posterior centre of pressure velocity in the FitFlop, attributed to its softer midfoot delaying progression. Hallux variables identified reductions in time spent ‘gripping’ as well as the magnitude of force applied by the hallux in swing in the FitFlop. Conclusions: Findings from the study identify that the FitFlop reduces pressure in key areas of the foot which are associated with walking comfort as well as clinical conditions. The ‘gripping’ mechanism postulated to hold flip-flops on is lessened in the FitFlop, potentially reducing the likelihood of overuse injuries.

Plantar Pressure Distribution in a Hyperpronated Foot before and after Intervention with an Extraosseous Talotarsal Stabilization Device—A Retrospective Study

Plantar pressure measurements have long been used by clinicians to provide information regarding potential impairments and disorders of the foot and ankle. Elevations in peak plantar pressures or a poor distribution of these pressures can be an indication of pathomechanics in the foot. Lower extremity deficits such as sensory impairment, foot deformities, limited joint mobility, and reduced plantar tissue thickness have been associated with high plantar pressures. The total pressures, pressure distribution, and peak pressures provide useful information to evaluate the abnormal functioning of the talotarsal joint. Instability of the talotarsal joint can result in excessive forces exerted on the joints and surrounding tissues in the foot that can then lead to dysfunction of the proximal musculoskeletal kinetic chain. In the present study, we performed a retrograde analysis of the pre- and postoperative measurements of the peak plantar pressures, peak forces, and area of contact between the foot and the ground during each phase of the gait cycle for 6 patients (12 feet) who had undergone a bilateral extraosseous talotarsal stabilization procedure using a type II extraosseous talotarsal stabilization device. After the procedure, a significant reduction was seen in the peak pressures (42%) over the entire foot and a significant increase in the contact area (19.7%) between the foot and the floor. This could imply that the extraosseous talotarsal stabilization procedure was effective in stabilizing the talotarsal joint complex, thus eliminating abnormal hindfoot motion and restoring the normal biomechanics of the foot and ankle complex, as indicated by a reduction and realignment of the peak plantar pressures and forces.