High plantar pressures contribute to skin breakdown in patients with diabetes mellitus and peripheral neuropathy. The primary purpose of this study was to determine the point during the stance phase of walking that corresponds with forefoot peak plantar pressures. Results indicate that peak plantar pressures occurred at 80% +/- 5% of the stance phase of gait in subjects with diabetes and transmetatarsal amputation, as well as in control subjects. Improved methods of footwear design or walking strategies proposed to patients should focus on the demands of the foot during the late stance phase of walking in order to increase available weightbearing area or to decrease forces, which will minimize plantar pressures and reduce trauma to the neuropathic foot.
The effects of the Youngswick osteotomy on plantar peak pressure distribution in the forefoot are presented for 17 patients (23 feet) with mild-to-moderate hallux limitus deformity and 23 control subjects (23 feet). During 2 years of follow-up, the operation produced a significant increase in the range of dorsiflexion of the first metatarsophalangeal joint in these patients, reaching near-normal values. Preoperative and postoperative measurements, using a pressure-distribution measurement system, show that peak pressure beneath the hallux and the first metatarsal head remained unchanged. However, peak pressure was significantly increased beneath the second metatarsal head and decreased beneath the fifth metatarsal head. These findings suggest that the foot functioned in a less inverted manner postoperatively. Compared with normal feet, hallux limitus feet demonstrated significantly higher peak pressure beneath the fourth metatarsal head preoperatively and postoperatively. (J Am Podiatr Med Assoc 94(1): 22-30, 2004)
Background: Comparing the dynamic pedobarographic patterns of individuals is common practice in basic and applied research. However, this process is often time-consuming and complex, and commercially available software often lacks powerful visualization and interpretation tools.
Methods: We propose a simple method for displaying pixel-level pedobarographic deviations over time relative to a so-called reference pedobarographic pattern. This novel method contains four distinct automated preprocessing stages: 1) normalization of pedobarographic fields (for foot length and width), 2) temporal normalization, 3) a pixel-level z-score–based calculation, and 4) color coding of the normalized pedobarographic fields. Group and patient-level comparisons were illustrated using an experimental data set including diabetic and nondiabetic patients.
Results: The automated procedure was found to be robust and quantified distinct temporal deviations in pedobarographic fields.
Conclusions: The advantages of the novel method cover several domains, including visualization, interpretation, and education.
The rigid relief orthosis was developed to protect vulnerable sites on the plantar surface of the insensitive foot against reulceration by providing both a nonyielding relief under the healed lesion site and a total contact fit. Clinically, the rigid relief orthosis has been effective in protecting the foot against the trauma induced by the repetitive mechanical stress of walking. This study used both the Hercules and F-Scan pressure transducer systems to measure pressure at the first metatarsal head in three orthotic treatments. Both measurement systems recorded significant reductions in pressure at the first metatarsal head with the rigid relief orthosis, establishing a quantitative rationale explaining its clinical effectiveness. Significant pressure differences were also recorded at the secondary sites of the heel, midfoot, and third metatarsal head.
The major goal of investigating plantar pressure in patients with pain or those at risk for skin injury is to reduce pressure under prominent metatarsal heads, especially the first and second metatarsals. In research, the insole is used to reduce plantar pressure by increasing the contact area in the midfoot region, which, in turn, induces an uncomfortable feeling near the arch during walking. It is deduced that sock structure can redistribute plantar pressure distribution.
Seven sock types with seven structures (plain, single cross tuck, mock rib inlay, cross miss, mock rib, double cross tuck, and double cross miss) for the sole area were produced. A plantar pressure measurement device was used to measure plantar static pressure in ten participants. The barefoot plantar pressure distribution was compared with the plantar pressure distribution with socks.
In the seven sock samples, the mean plantar pressure of the cross miss and mock rib structures at high plantar pressure zones (toe and first through fourth metatarsal bone regions) were decreased, and, as a result, the pressure shifted to relatively low pressure zones (fifth metatarsal bone and midfoot regions).
These results indicate that wearing socks with cross miss and mock rib structures will reduce mean plantar pressure values compared with the barefoot condition in high plantar pressure zones. In general, the results suggest that mean plantar pressure is redistributed from high to low plantar pressure zones.
The purpose of this study was to determine if pressure data, collected after taking one step or two steps, were similar to values obtained by using the traditional midgait method. Ten healthy subjects, with a mean age of 27 years, walked across a sensor platform sampling at 70 Hz. Each subject was randomly assigned to take one step, two steps, or multiple steps (midgait method) across the sensor platform. The results of the study indicate that the two-step method, in comparison with the one-step method, provides pressure data more representative of the midgait method, and different values for pressure and force will be obtained, depending on the method of pressure data collection selected by the clinician.
Different closed kinematic tasks may present different magnitudes of knee abduction, foot pronation, and foot plantar pressure and area. Although there are plenty of studies comparing knee abduction between different tasks, the literature lacks information regarding differences in foot pronation and foot plantar pressure and area. We compared foot angular displacement in the frontal plane and foot plantar pressure and area among five closed kinematic tasks.
Forefoot and rearfoot angular displacement and foot plantar pressure and area were collected in 30 participants while they performed the following tasks: stair descent, single-leg step down, single-leg squat, single-leg landing, and drop vertical jump. Repeated-measures analyses of variance were used to investigate differences between tasks with α = 0.05.
Single-leg squat and stair descent had increased foot total plantar area compared with single-leg landing (P = .005 versus .027; effect size [ES] = 0.66), drop vertical jump (P = .001 versus P = .001; ES = 0.38), and single-leg step down (P = .01 versus P = .007; ES = 0.43). Single-leg landing and single-leg step down had greater foot total plantar area compared with drop vertical jump (P = .026 versus P = .014; ES = 0.54). There were differences also in rearfoot and midfoot plantar area and pressure and forefoot plantar pressure.
Differences in foot-striking pattern, magnitude of ground reaction force, and task speed might explain these findings. Clinicians should consider these findings to improve decisions about tasks used during rehabilitation of patients with foot conditions.
The etiology of ulcerations related to increased plantar pressure in patients with diabetes mellitus is complex but frequently includes a component of gastrocnemius soleus equinus. One viable treatment option is percutaneous tendo Achillis lengthening as a means of increasing dorsiflexory range of motion and decreasing forefoot shear forces. This article presents three case reports illustrating the importance of reducing plantar pressure as a crucial component of treatment of diabetic forefoot ulcerations. (J Am Podiatr Med Assoc 95(3): 281–284, 2005)