Casting Methods and Plantar Pressure
Effects of Custom-made Foot Orthoses on Dynamic Plantar Pressure Distribution
Foot orthoses are widely used to treat various foot problems. A literature search revealed no publications on differences in plantar pressure distribution resulting from casting methods for foot orthoses. Four casting methods were used for construction of orthoses. Two foam box techniques were used: accommodative full weightbearing method (A) and functional semiweightbearing method (B). Also, two suspension plaster casting techniques were used: accommodative casting (C) and functional subtalar joint neutral position (Root) method (D). Their effects on contact area, plantar pressure, and walking convenience were evaluated. All orthoses increased the total contact area (mean, 17.4%) compared with shoes without orthoses. Differences in contact areas between orthoses for total plantar surface were statistically significant. Peak pressures for the total plantar surface were lower with orthoses than without orthoses (mean, 22.8%). Among orthoses, only the difference between orthoses A and B was statistically significant. Differences between orthoses for the forefoot were small and not statistically significant. The gait lines of the shoe without an insole and of the accommodative orthoses are more medially located than those of functional orthoses. Walking convenience in the shoe was better rated than that with orthoses. There were no differences in perception of walking convenience between orthoses A, B, and C. Orthosis D had the lowest convenience rating. The four casting methods resulted in differences between orthoses with respect to contact areas and walking convenience but only slight differences in peak pressures. (J Am Podiatr Med Assoc 96(1): 9–18, 2006)
We sought to investigate the magnitude and duration of peak forefoot plantar pressures in rheumatoid arthritis. The spatial and temporal characteristics of forefoot plantar pressures were measured in 25 patients with a positive diagnosis of rheumatoid arthritis of 5 to 10 years’ duration (mean, 8 years) and a comparison group using a platform-based pressure-measurement system. There were no significant differences between groups in the magnitude of peak plantar pressure in the forefoot region. Significant differences were, however, noted for temporal aspects of foot-pressure measurement. The duration of loading over sensors detecting peak plantar pressure was significantly longer in the rheumatoid arthritis group. In addition, the rheumatoid arthritis group demonstrated significantly greater force–time integrals. Significant increases in the temporal parameters of plantar pressure distribution, rather than those of amplitude, may be characteristic of the rheumatoid foot. (J Am Podiatr Med Assoc 94(3): 255–260, 2004)
Background: During pregnancy, physical and hormonal modifications occur. Morphologic alterations of the feet are found. These observations can induce alterations in plantar pressure. This study sought to investigate plantar pressures during gait in the last 4 months of pregnancy and in the postpartum period. A comparison with nulliparous women was conducted to investigate plantar pressure modifications during pregnancy.
Methods: Fifty-eight women in the last 4 months of pregnancy, nine postpartum women, and 23 healthy nonpregnant women (control group) performed gait trials on an electronic walkway at preferred speeds. The results for the three groups were compared using analysis of variance.
Results: During pregnancy, peak pressure and contact area decreased for the forefoot and rearfoot. These parameters increased significantly for the midfoot. The gait strategy seemed to be lateralization of gait with an increased contact area of the lateral midfoot and both reduced pressure and a later peak time on the medial forefoot. In the postpartum group, footprint parameters were modified compared with the pregnant group, indicating a trend toward partial return to control values, although differences persisted between the postpartum and control groups.
Conclusions: Pregnant women had altered plantar pressures during gait. These findings could define a specific pattern of gait footprints in late pregnancy because plantar pressures had characteristics that could maintain a stable and safe gait.
This study examined the incidence of high peak plantar pressure and plantar callus in 211 adolescents with diabetes mellitus and 57 nondiabetic controls. The percentage of subjects with these anomalies was the same in both groups. Although diabetic subjects were no more likely than nondiabetic controls to have high peak plantar pressure and callus, these anomalies place individuals with diabetes at greater risk of future foot problems. The effects of orthoses, cushioning, and both in combination were monitored in 17 diabetic subjects with high peak plantar pressure and in 17 diabetic subjects with plantar callus; reductions of up to 63% were achieved. Twelve-month follow-up of diabetic subjects fitted with orthoses showed a significant reduction in peak plantar pressure even when the orthoses were removed. The diabetic subjects who had not received any interventions during the same 12-month period showed no significant change in peak plantar pressure. (J Am Podiatr Med Assoc 93(3): 214-220, 2003)
We sought to determine whether one of two prefabricated insole designs could better manage high forefoot plantar pressures in patients with rheumatoid arthritis. Ten subjects with rheumatoid arthritis who experienced pain with shod weightbearing were studied by using a plantar pressure measurement system. Two insole designs and a shoe-only control condition were randomly tested in repeated trials. Dome- and bar-shaped metatarsal pads made of latex foam were incorporated into full-length insoles made of urethane. Significant reductions in mean peak plantar pressures over the central metatarsals were noted when using the insole and dome pad design (12% [33 kPa]) and the insole and bar pad design (21% [58 kPa]) compared with the shoe-only condition. A prefabricated insole design incorporating a bar metatarsal pad is recommended to manage high forefoot plantar pressures in patients with rheumatoid arthritis. (J Am Podiatr Med Assoc 94(3): 239-245, 2004)
Assessing Plantar Pressure Distribution in Children with Flatfoot Arch
Application of the Clarke Angle
Flatfoot, or pes planus, is one of the most common foot posture problems in children that may lead to lower-extremity pain owing to a potential increase in plantar pressure. First, we compared plantar pressure distribution between children with and without flatfoot. Second, we examined the reliability and accuracy of a simple metric for characterization of foot posture: the Clarke angle. Third, we proposed a mathematical model to predict plantar pressure magnitude under the medial arch using body mass and the Clarke angle.
Sixty children with flatfoot and 33 aged-matched controls were recruited. Measurements included in-shoe plantar pressure distribution, ground reaction force, Clarke angle, and radiography assessment. The measured Clarke angle was compared with radiographic measurements, and its test-retest reliability was determined. A mathematical model was fitted to predict plantar pressure distribution under the medial arch using easy-to-measure variables (body mass and the Clarke angle).
A high correlation was observed between the Clarke angle and radiography measurements (r > 0.9; P < 10−6). Excellent between- and within-day test-retest reliability for Clarke angle measurement (intraclass correlation coefficient, >0.9) was observed. Results also suggest that pressure magnitude under the medial arch can be estimated using the Clarke angle and body mass (R 2 = 0.95; error, <0.04 N/cm2 [2%]).
This study suggests that the Clarke angle is a practical, reliable, and sensitive metric for quantification of medial arch height in children and could be recommended for research and clinical applications. It can also be used to estimate plantar pressure under the medial arch, which, in turn, may assist in the timely intervention and prognosis of prospective problems associated with flatfoot posture.
In-Shoe Plantar Pressure Profiles in Amateur Basketball Players
Implications for Footwear Recommendations and Orthosis Use
Biomechanical analysis of foot loading characteristics may provide insights into the injury mechanisms and guide orthotic prescription for basketball players. This study aimed to quantify in-shoe plantar pressure profiles in amateur players when executing typical basketball movements.
Twenty male university basketball players performed four basketball-specific movement tasks—running, maximal forward sprinting, maximal 45° cutting, and layup—in a pair of standardized basketball shoes fitted with an in-shoe plantar pressure measurement system. Peak pressure (PP) and pressure-time integral (PTI) data were extracted from ten plantar regions. One-way repeated-measures analysis of variance was performed across the tasks, with significance set at P < .05.
Distinct plantar pressure distribution patterns were observed among the four movements. Compared with running, significantly higher (P < .05) PP and PTI of up to approximately 55% were found in sprinting and layup, particularly at the forefoot region. Similarly, significantly higher (P < .05) PPs and PTIs, ranging from approximately 23% to 90%, were observed in 45° cutting compared with running at most foot regions.
Compared with running, sprinting and layup demonstrated higher plantar loading in the forefoot region, and 45° cutting yielded increased plantar loading in most regions of the foot. Understanding the plantar pressure characteristics of different movements may be useful in optimizing footwear designs, orthosis use, or training strategies to minimize regional plantar loading during amateur basketball play.
Background: The effectiveness of different energy levels used in extracorporeal shockwave therapy (ESWT) have been investigated in previous studies, but controversy remains regarding which energy levels should be used in the treatment of plantar fasciitis. The objective of this study was to compare the efficacy of different energy levels used in ESWT in the treatment of plantar fasciitis through comparisons of plantar fascia thickness and pressure distribution.
Methods: Between July 2020 and September 2020, a total of 51 patients (71 feet) with plantar fasciitis were randomized into three treatment groups using the sealed envelope method. Group 1 (n = 25) received low energy density (0.09 mJ/mm2 ), Group 2 (n = 25) received medium energy density (0.18 mJ/mm2), and Group 3 (n = 21) received high energy density (0.38 mJ/mm2). All groups received three sessions of ESWT with a frequency of 2,000 shocks/min at one week intervals. The patients were evaluated before and after treatment using a visual analog scale (VAS) for pain, the Foot Function Index (FFI), and plantar fascia thickness measured by ultrasonography, and plantar pressure distribution.
Results: The posttreatment VAS and FFI scores were determined to be statistically significantly lower than the pretreatment values in all three groups (p<0.001). There was no significant difference between the groups in terms of the pre and post treatment values of VAS, FFI scores, plantar fascia thickness and pressure distribution (p>0.05). No statistically significant difference was found between the groups in terms of percentage changes in all the outcome parameters (p>0.05).
Conclusions: The results of the study suggest that neither low, medium, or high levels of ESWT were superior to one another in terms of pain, foot functions, fascia thickness and pressure distribution in the treatment of plantar fasciitis.
Background: Walking at various speeds and durations may result in different peak plantar pressure (PPP). However, there is no study comparing the effect of walking speeds and durations on PPP. The purpose of this study was to explore whether different walking speeds and durations significantly change PPP and establish a normal response in healthy people.
Methods: An in-shoe plantar pressure system was used to measure PPP under the first toe, first metatarsal, second metatarsal, and heel regions in 12 healthy, young people. All participants performed six walking trials at three speeds (3, 6, and 9 km/h) and for two durations (10 and 20 min). The 3 × 2 two-way analysis of variance was used to examine the main effects of speeds and durations and their interaction.
Results: The results showed that walking speeds significantly affected PPP and that walking duration did not. No interaction between the walking speed and duration was observed. Peak plantar pressure values under the first toe and the first metatarsal head were significantly higher (P < .05) at 9 km/h (509.1 ± 314.2 kPa and 591.4 ± 302.4 kPa, respectively) than at 3 km/h (275.4 ± 168.7 kPa and 369.4 ± 205.4 kPa, respectively) after 10-min walking.
Conclusions: People at risk for foot ulcers may use slow and brisk walking for exercise to reduce PPP, thus reducing risk for foot ulcers. Our study demonstrated that slow running at 9 km/h significantly increases PPP.
Background: Frequent use of walking boots in podiatric medicine often elicits patient complaints and sequelae from the imposed limb-length discrepancy. This study was designed primarily to determine whether peak plantar pressures are decreased in the contralateral foot when a moderately worn athletic shoe is worn opposite a high-calf walking boot and, if so, secondarily to determine whether a specialized surgical shoe worn on the contralateral foot can also effectively reduce this pressure. The pressure reductions were then compared to determine whether significantly greater plantar pressure reduction was provided by either the athletic shoe or the surgical shoe.
Methods: Participants without a foot abnormality walked on a treadmill in four footwear combinations: barefoot bilaterally, high-calf rocker-bottom sole (HCRB) walking boot/ barefoot, HCRB walking boot/athletic shoe, and HCRB walking boot/modified walking boot shoe. Measurements were taken with the participants wearing socks. Peak plantar calcaneal pressures were collected.
Results: Peak plantar pressures under the calcaneus opposite the HCRB walking boot were significantly reduced from barefoot pressures when either an athletic shoe or the modified walking boot shoe was worn. However, no significant difference was seen when comparing the reduction by the athletic shoe with that by the modified walking boot.
Conclusions: Wearing an athletic shoe on the foot opposite an HCRB walking boot reduces calcaneal pressures; however, wearing a modified device with structural properties of an HCRB walking boot sole is no better than an athletic shoe at reducing peak calcaneal pressures. (J Am Podiatr Med Assoc 101(2): 127–132, 2011)