The primary purpose of this study was to determine the magnitude and duration of plantar pressures acting on the feet of American Indians with diabetes mellitus. A secondary purpose was to determine whether differences in the range of motion of the ankle and first metatarsophalangeal joints existed between American Indians with and without diabetes. Three groups of American Indian subjects were tested: a control group (n = 20); a group with diabetes but no peripheral neuropathy (n = 24); and a group with diabetes and peripheral neuropathy (n = 21). A floor-mounted pressure sensor platform was used to collect plantar pressure data while subjects walked barefoot. The results indicated that American Indians with diabetes have 1) a pattern of peak plantar pressure similar to patterns previously reported for non–American Indians with diabetes and 2) a reduction in ankle and first metatarsophalangeal joint range of motion in comparison with nondiabetic American Indians. (J Am Podiatr Med Assoc 91(6): 280-287, 2001)
Background: Running can be considered a high-impact practice, and most people practicing continuous running experience lower-limb injuries. The aim of this study was to determine the influence of 45 min of running on foot posture and plantar pressures.
Methods: The sample comprised 116 healthy adults (92 men and 24 women) with no foot-related injuries. The mean ± SD age of the participants was 28.31 ± 6.01 years; body mass index, 23.45 ± 1.96; and training time, 11.02 ± 4.22 h/wk. Outcome measures were collected before and after 45 min of running at an average speed of 12 km/h, and included the Foot Posture Index (FPI) and a baropodometric analysis.
Results: The results show that foot posture can be modified after 45 min of running. The mean ± SD FPI changed from 6.15 ± 2.61 to 4.86 ± 2.65 (P < .001). Significant decreases in mean plantar pressures in the external, internal, rearfoot, and forefoot edges were found after 45 min of running. Peak plantar pressures in the forefoot decreased after running. The pressure-time integral decreased during the heel strike phase in the internal edge of the foot. In addition, a decrease was found in the pressure-time integral during the heel-off phase in the internal and rearfoot edges.
Conclusions: The findings suggest that after 45 min of running, a pronated foot tends to change into a more neutral position, and decreased plantar pressures were found after the run.
Plantar pressure measurement is effective for assessing plantar loading and can be applied to evaluating foot performance. We sought to explore the characteristics of plantar pressures in elite sprinters and recreational runners during static standing and walking.
Arch index (AI) values, regional plantar pressure distributions (PPDs), and footprint characteristics were examined in 80 elite sprinters and 90 recreational runners using an optical plantar pressure measurement system. Elite sprinters' pain profiles were examined to evaluate their most common pain areas.
In recreational runners, AI values in males were in the normal range and in females were high arch type. The AI values were significantly lower in elite sprinters than in recreational runners. In elite sprinters, particularly males, the static PPD of both feet was higher at the medial metatarsal bone and the lateral heel and lower at the medial and lateral longitudinal arches. Elite male sprinters' PPD of both feet was mainly transferred to the medial metatarsal bone and decreased at the lateral longitudinal arch and the medial heel during the midstance phase of walking. The lateral knee joint and biceps femoris were the most common sites of musculoskeletal pain in elite sprinters.
Elite sprinters' AI values could be classified as high arches, and their PPD tended to parallel the features of runners and high-arched runners. These findings correspond to the profile of patellofemoral pain syndrome (PFPS)–related plantar pressure. The pain profiles seemed to resonate with the symptoms of high-arched runners and PFPS. A possible link between high-arched runners and PFPS warrants further study.
The aim of this study was to evaluate whether high plantar foot pressures can be predicted from measurements of plantar soft-tissue thickness in the forefoot of diabetic patients with neuropathy. A total of 157 diabetic patients with neuropathy and at least one palpable foot pulse but without a history of foot ulceration were invited to participate in the study. Plantar tissue thickness was measured bilaterally at each metatarsal head, with patients standing on the same standardized platform. Plantar pressures were measured during barefoot walking using the optical pedobarograph. Receiver operating characteristic analysis was used to determine the plantar tissue thickness predictive of elevated peak plantar pressure. Tissue thickness cutoff values of 11.05, 7.85, 6.65, 6.55, and 5.05 mm for metatarsal heads 1 through 5, respectively, predict plantar pressure at each respective site greater than 700 kPa, with sensitivity between 73% and 97% and specificity between 52% and 84%. When tissue thickness was used to predict pressure greater than 1,000 kPa, similar results were observed, indicating that high pressure at different levels could be predicted from similar tissue thickness cutoff values. The results of the study indicate that high plantar pressure can be predicted from plantar tissue thickness with high sensitivity and specificity. (J Am Podiatr Med Assoc 94(1): 39-42, 2004)
Joint hypermobility is a connective tissue disorder that increases joint range of motion. Plantar pressure and foot loading patterns may change with joint hypermobility. We aimed to analyze static plantar pressure in young females with and without joint hypermobility.
Joint laxity in 27 young females was assessed cross sectionally using the Beighton and Horan Joint Mobility Index. Participants were divided into the hypermobility (score, 4–9) and no hypermobility (score, 0–3) groups according to their scores. Static plantar pressure and forces were recorded using a pedobarographic mat system.
Higher peak pressures (P = .01) and peak pressure gradients (P = .025) were observed in the nondominant foot in the hypermobility group. According to the comparison of dominant and nondominant feet in each group, the hypermobility group showed significantly higher peak pressures (P = .046), peak pressure gradients (P = .041), and total force values (P = .028) in the nondominant foot.
The plantar pressure and loading patterns vary in young females with joint hypermobility. Evaluation of plantar loading as an injury prevention tool in individuals with joint hypermobility syndrome can be suggested.
A study was conducted to determine whether a pedograph could be used as a field-based screening tool to predict pressures generated on the plantar surfaces of the feet of prepubertal children during single-limb weightbearing stance. Plantar pressures were collected in 51 primary school–aged children using a pressure distribution measurement system. Statistically significant negative correlations were found between footprint angle and both peak force (r = −0.453) and peak area (r = −0.539), and statistically significant positive correlations were found between the Chippaux-Smirak Index and both peak force (ρ= 0.285) and peak area (ρ = 0.559). Although statistically significant, the weak relationships precluded foot structure variables from being used to predict the plantar pressures of children during static weightbearing. It is therefore recommended that an alternative field-based tool that directly measures plantar pressures be used to screen children in the public school system to identify those at risk of excessive plantar pressures. (J Am Podiatr Med Assoc 94(5): 429–433, 2004)
The purpose of this study was to determine the degree of symmetry for in-shoe plantar pressure and vertical force patterns between the left and right feet of healthy subjects during walking. Thirty subjects with a mean age of 29.6 years participated in the study. Each subject walked a distance of 8 m three times while in-shoe plantar pressure and vertical force data were collected. A total of 12 steps were analyzed for both feet, and maximum vertical force, peak pressure, and pressure-time integrals were calculated for four plantar regions of the foot. No differences in the three variables were noted between male and female subjects. Plantar pressure and vertical force patterns were found to be symmetrical between the left and right feet, except for two of the four plantar regions studied. Only the forefoot and rearfoot regions were found to show significant differences between the left and right feet for plantar pressure and vertical force, respectively. The degree of asymmetry for these two plantar regions in the same foot, however, was minimal. (J Am Podiatr Med Assoc 91(7): 337-342, 2001)
Background: A few studies have investigated the relationship between foot posture measures and plantar pressure parameters, but no study has investigated the correlation of foot posture measures with all primary parameters consisting of contact area (CA), maximum force (MF), and peak pressure (PP). We aimed to determine the relationship of the Foot Posture Index-6 (FPI-6) and navicular drop (ND) with plantar pressure parameters during static standing and preferred walking.
Methods: Seventy people were included. Navicular drop and the FPI-6 were used to assess foot posture. Plantar pressure parameters including CA, MF, and PP were recorded by a pressure-sensitive mat during barefoot standing and barefoot walking at preferred speed. All assessments were repeated three times and averaged. Pearson correlation coefficients below 0.300 were accepted as negligible and higher ones were interpreted.
Results: Navicular drop was moderately correlated with dynamic CA under the midfoot and second metatarsal; also, the FPI-6 was moderately correlated with dynamic CA under the midfoot (0.500 < r < 0.700). The other interpreted correlations were poor (0.300 < r < 0.500). Both measures were correlated with dynamic CA under the second and third metatarsals; dynamic CA and MF under the midfoot; and static CA, MF, and PP under the first metatarsal and hallux (P < .01). Navicular drop was also correlated with dynamic MF under the first metatarsal and dynamic CA under the fourth metatarsal (P < .01). Furthermore, ND was correlated with static CA and PP under the second metatarsal and static PP under the fifth metatarsal (P < .01). The FPI-6 was also correlated with dynamic MF and PP under the hallux (P < .01).
Conclusions: The correlations between foot posture measures and plantar pressure variables are poor to moderate. The measures may be useful in the clinical assessment of medial forefoot problems related to prolonged standing and midfoot complaints related to high force during walking. Furthermore, the FPI-6 may provide valuable data regarding hallux complaints related to the high loads during walking.
Plantar pressure measurements are commonly used to evaluate foot function in chronic musculoskeletal conditions. However, manually identifying anatomical landmarks is a source of measurement error and can produce unreliable data. The aim of this study was to evaluate intratester reliability associated with manual masking of plantar pressure measurements in patients with gout.
Twenty-five patients with chronic gout (mean disease duration, 22 years) were recruited from rheumatology outpatient clinics. Patients were excluded if they were experiencing an acute gout flare at the time of assessment, had lower-limb amputation, or had diabetes mellitus. Manual masking of peak plantar pressures and pressure-time integrals under ten regions of the foot were undertaken on two occasions on the same day using an in-shoe pressure measurement system. Test-retest reliability was assessed by using intraclass correlation coefficients, SEM, 95% limits of agreement, and minimal detectable change.
Mean peak pressure intraclass correlation coefficients ranged from 0.92 to 0.97, with SEM of 8% to 14%. The 95% limits of agreement ranged from−150.3 to 133.5 kPa, and the minimal detectable change ranged from 30.8 to 80.6 kPa. For pressure-time integrals, intraclass correlation coefficients were 0.86 to 0.94, and SEM were 5% to 29%, with the greater errors observed under the toes. The 95% limits of agreement ranged from −48.5 to 48.8 kPa/sec, and the minimal detectable change ranged from 6.8 to 21.0 kPa/sec.
These findings provide clinicians with information confirming the errors associated with manual masking of plantar pressure measurements in patients with gout. (J Am Podiatr Med Assoc 101(5): 424–429, 2011)
Plantar pressure assessments are useful for understanding the functions of the foot and lower limb and for predicting injury incidence rates. Musculoskeletal fatigue is likely to affect plantar pressure profiles. This study aimed to characterize college elite basketball players' plantar pressure profiles and pain profiles during static standing and walking.
Fifty-one male elite basketball players and 85 male recreational basketball players participated in this study. An optical plantar pressure measurement system was used to collect the arch index (AI), regional plantar pressure distributions (PPDs), and footprint characteristics during static and dynamic activities. Elite basketball players' pain profiles were examined for evaluating their common musculoskeletal pain areas.
The AI values were in the reference range in recreational basketball players and considerably lower in elite basketball players. Elite basketball players' static PPDs of both feet were mainly exerted on the lateral longitudinal arch and the lateral heel and were relatively lower on the medial longitudinal arch and medial and lateral metatarsal bones. The PPDs mainly transferred to the lateral metatarsal bone and lateral longitudinal arch and decreased at the medial heel during the midstance phase of walking. The footprint characteristics of elite basketball players illustrated the features of calcaneal varus (supinated foot) of high arches and dropped cuboid foot. The lateral ankle joints and anterior cruciate ligaments were the common musculoskeletal pain areas.
Elite basketball players' AI values indicated high arches, and their PPDs tended to parallel the features of the high-arched supinated and dropped cuboid foot. Their pain profiles resonated with the common basketball injuries and reflected the features of Jones fracture and cuboid syndrome. The potential links among high-arched supinated foot, Jones fracture, and cuboid syndrome are worth further study.