Background: Plantar first metatarsal ulcerations pose a difficult challenge to clinicians. Etiologies vary and include first metatarsal declination, cavus foot deformity, equinus contracture, and hallux limitus/rigidus. Our pragmatic, sequential approach to the multiple contributing etiologies of increased plantar pressure sub–first metatarsal can be addressed through minimal skin incisions.
Methods: A retrospective review was performed for patients with surgically treated preulcerations or ulcerations sub–first metatarsal head. All of the patients underwent a dorsiflexory wedge osteotomy, and the need for each additional procedure was independently assessed. Equinus contracture was treated with Achilles tendon lengthening, cavovarus deformity was mitigated with Steindler stripping, and plantarflexed first ray was treated with dorsiflexory wedge osteotomy.
Results: Eight patients underwent our pragmatic, sequential approach for increased plantar pressure sub–first metatarsal, four with preoperative ulcerations and four with preoperative hyperkeratotic preulcerative lesions. The preoperative ulcerations were present for an average of 25.43 weeks (range, 6.00–72.86 weeks), with an average size of 0.19 cm3 (median, 0.04 cm3). Procedure breakdown was as follows: eight first metatarsal osteotomies, four Achilles tendon lengthenings, and six Steindler strippings. Postoperatively, all eight patients returned to full ambulation, and the four ulcerations healed at an average of 24 days (range, 15–38 days). New ulceration occurred in one patient, and postoperative infection occurred in one patient. There were no ulceration recurrences, dehiscence of surgical sites, or minor or major amputations.
Conclusions: The outcomes in patients surgically treated for increased plantar first metatarsal head pressure were evaluated. This case series demonstrates that our pragmatic, sequential approach yields positive results. In diabetic or high-risk patients, it is our treatment algorithm of choice for increased plantar first metatarsal pressure.
Offloading devices for diabetic foot ulcers (DFU) generally restrict exercise. In addition to traditional health benefits, exercise could benefit DFU by increasing blood flow and acting as thermotherapy. This study functionally evaluated a cycling cleat designed for forefoot DFU.
Fifteen individuals at risk of developing a DFU used a recumbent stationary bicycle to complete one 5-minute cycling bout with the DFU cleat on their study foot and one 5-minute bout without it. Foot stress was evaluated by plantar pressure insoles during cycling. Laser Doppler perfusion monitored blood flow to the hallux. Infrared photographs measured foot temperature before and after each cycling bout.
The specialized cleat significantly reduced forefoot plantar pressure (9.9 kPa versus 62.6 kPa, P < .05) and pressure time integral (15.4 versus 76.4 kPa*sec, P < .05). Irrespective of footwear condition, perfusion to the hallux increased (3.97 ± 1.2 versus 6.9 ± 1.4 tissue perfusion units, P < .05) after exercise. Infrared images revealed no changes in foot temperature.
The specialized cleat allowed participants to exercise with minimal forefoot stress. The observed increase in perfusion suggests that healing might improve if patients with active DFU were to use the cleat. Potential thermotherapy for DFU was not supported by this study. Evaluation of the device among individuals with active DFU is now warranted.
Background: This study investigated the effects of two low-Dye and two high-Dye strapping techniques that are commonly used to treat pronatory sequelae.
Methods: Plantar pressure distribution in normal adults with a pronated foot type was assessed with a commercially available pressure platform system. Twenty study participants first walked across the platform barefoot and then with each of the four strapping conditions applied. The footprints were averaged and divided into seven areas for analysis.
Results: Paired t tests found significant differences between the barefoot and strapping conditions. Overall, there was a general lateralization of pressures indicating an antipronation effect from all strapping conditions. Low-Dye strap 2, used to limit the degree of calcaneal eversion, produced the most significant changes at the foot pressure areas analyzed.
Conclusions: The data reported in this study suggest that the four strapping techniques offer different levels of control, and this should be considered during the decision-making process and clinical management of pronatory conditions. It was the contention of this study that low-Dye strap 2 was the most effective strapping technique to control foot mechanics associated with a pronated foot type. (J Am Podiatr Med Assoc 99(5): 391–398, 2009)
Abnormal plantar pressures are the hallmark characteristic of several conditions and pathologic abnormalities. Pressure platforms allow for quick and accurate screening of patients and help guide clinical treatment. However, it is essential to evaluate the reliability and repeatability of these devices before making clinical decisions. The purpose of this study was to determine the reliability of the EPS-Platform during static and dynamic activities.
Fifty-six healthy individuals stood and walked onto the pressure platform. Five trials were performed during two separate testing sessions to determine intrasession and intersession reliability. Pressure data were obtained and several variables of interest were calculated for intrasession and intersession reliability using intraclass correlation coefficients (ICCs), SEM, percent error, and coefficient of variation.
Static and dynamic intrasession and intersession reliability produced moderate-to-excellent ICCs, low SEMs, low percent errors, and low coefficients of variation. Static trials had higher ICCs, lower percent errors, and lower coefficients of variation compared with dynamic trials. Intersession reliability also had higher ICCs, lower percent errors, and lower coefficients of variation compared with intrasession reliability.
This study demonstrates that the EPS-Platform is a reliable device for collecting gait plantar pressures. Static trials produce better reliability, most likely owing to the large inherent variability during dynamic gait. Intersession reliability was higher than intrasession reliability owing to the intersession measures being calculated with an average of five trials. By averaging the trials, the variability of gait is decreased, and this improves the accuracy of the results. These results can be used as the basis for future studies and to determine a priori sample sizes for investigations that use the EPS-Platform. (J Am Podiatr Med Assoc 103(3): 197–203, 2013)
Any pathomechanical change in the foot or ankle is expected to cause adverse biomechanical effects on the lumbopelvic region. However, no objective data can be found in the literature regarding the effects of musculus transversus abdominis (mTrA) and musculus lumbar multifidus (mLM), which are effective muscles in lumbopelvic motor control, or regarding the extent of their effects.
Sixty-four healthy young adults were assessed by a physiotherapist (C.K.) experienced in treating feet and a radiologist (Y.D.) specialized in muscular imaging. In the determination of biomechanical properties of the foot, the navicular drop test (NDT), Foot Posture Index (FPI), pedobarographic plantar pressure analysis, and isokinetic strength dynamometer measurements were used in determining the strength of the muscles around the ankle. Ultrasonographic imaging was used to determine mTrA and mLM thicknesses.
Significant correlation was found between NDT results and mTrA and mLM thicknesses (P < .05) and between FPI results and mTrA thicknesses (P < .05). As the peak pressure of the foot medial line increased, mTrA and mLM thicknesses decreased (P < .05). Although dorsiflexion muscle strength was also effective, mTrA and mLM thicknesses were found to increase especially as plantarflexion muscle strength increased (P < .05).
These results show that the biomechanical and musculoskeletal properties of the foot-ankle are associated with lumbopelvic stability.
Weakness of the toe flexor muscles has been attributed to the development of toe pathologies, and it responds well in the clinic to toe grip exercises. However, it is unknown whether exercising the toe flexor muscles improves the ability to grip and alter function. The aim of this study was to assess the effect of toe flexor exercises on apical plantar pressure, as a measure of grip, while seated and during gait.
Twenty-three individuals with no known toe pathologies were recruited. Static peak pressure, time spent at peak pressure, and pressure-time integral while seated, as well as dynamic forefoot maximal force, contact area, and percentage contact time, were recorded before and after exercise. Toe grip exercises with a therapy ball were completed daily for 6 weeks.
Static peak pressure significantly increased after exercise on the apex of the second and third digits, as did the pressure-time integral. Dynamic peak force and contact area did not alter after exercise around the metatarsals and toes, yet percentage contact time significantly increased for each metatarsal after completing daily toe grip exercises.
Exercises to improve the grip ability of the toes increased the static peak pressure on the apex of the second and third digits as well as the percentage contact time of the metatarsals during gait. The ability to increase apical peak pressure and contact time after exercises could assist in improving forefoot stability and gait efficiency and in reducing toe pathology progression.
Altered foot loading during weightbearing is suggested to play a role in the development of patellofemoral pain (PFP). This study aimed to determine foot-loading characteristics associated with PFP by assessing center of pressure (COP) during single-limb loading in individuals with PFP compared with noninjured controls.
Thirty recreationally active patients with PFP and 30 noninjured control participants had barefoot plantar pressure assessed during single-limb squats (SLSs) from which COP parameters (COP velocity and COP index) were obtained. Groups were compared using independent t tests.
Individuals with PFP demonstrated a greater COP index (P = .042), indicating a more lateral foot-loading pattern, and exhibited increased overall COP velocity (P = .013) and anteroposterior COP velocity during SLSs compared with control participants (P = .033).
Greater lateral foot loading and increased COP velocity during SLSs demonstrated by individuals with PFP may indicate reduced dynamic balance in this patient group, which may be implicated in the development of PFP.
Patellofemoral pain (PFP) is a common injury, particularly in females. Foot pronation may promote knee and hip transverse plane joint kinematics during gait thought to contribute to PFP. Greater knowledge of plantar loading characteristics in females with PFP may be valuable to provide a basis for clinical decisions regarding footwear and foot orthoses. The purpose of this study was to compare plantar loading distribution in females with and without PFP during gait.
Plantar pressure during walking was recorded from 19 females with PFP and 20 females without PFP. Contact area, peak force, and force-time integral were evaluated in ten plantar areas. Arch index was also calculated from contact area data during gait.
Contact area in females with PFP was 9% smaller in the first metatarsal region (P = .039) and 20% smaller in the midfoot region (P = .042) than in females without PFP. Peak force was 31% lower in the midfoot region for females with PFP (P = .027) and 13% lower in the first metatarsal region (P = .064). Force-time integral was 18% lower in the first metatarsal region in females with PFP (P = .024). Females with PFP demonstrated a lower arch index (suggesting a higher arch) (P = .028).
Decreased medial forefoot loading and decreased midfoot contact suggest decreased foot pronation during gait in females with PFP relative to females without PFP. Decreased foot pronation may foster increased patellofemoral joint loading rates. These data contribute to rationale for footwear modifications to modify plantar loading characteristics in people experiencing PFP.
Rheumatoid arthritis (RA) often affects feet with progressive pathologic changes to foot morphology and pressure distribution. Studies in RA suggest that reductions in forefoot peak pressures can reduce pain. We investigated the effects of off-the-shelf foot orthoses on plantar foot pressures in patients with early RA.
Thirty-five patients with early RA were recorded walking. Variables measured were forefoot peak plantar pressure (PPPft), forefoot pressure-time integral (PTIft), and hallux and lesser toe and midfoot contact areas. Patients were analyzed while walking barefoot, with shoes, and with shoes and foot orthoses. Measurements were taken at baseline and at 3 and 6 months.
There were significantly increased PPPft values between barefoot and shod and between barefoot and orthoses (P < .01). However, there was a significant reduction in PPPft during the 6 months with orthoses compared with shoes only (P < .01). Foot orthoses significantly reduced PTIft over 6 months (P < .01). Results also demonstrated a significant increase in hallux and lesser toe (P < .01) and midfoot (P < .01) contact areas during the 6 months with foot orthoses.
In patients with early RA, off-the-shelf foot orthoses cause a significant reduction of 22% in PPPft and 14% in PTIft as soon as insoles are worn compared with shod. Further reductions for orthoses compared with baseline were found by 3 months (15% in PPPft and 14% in PTIft) and 6 months (33% in PPPft and 33% in PTIft). These findings could contribute to reductions in foot pain.
Background: Foot blisters are common and painful nuisances in competitive sports and in military service. The pathogenesis of the problem is related to excessive frictional forces experienced on or under the foot. The incidence of foot blisters in marathon runners can reach 39%. Similarly, up to 42% of cadets in Reserve Officers’ Training Corps camps might be prone to foot blisters. Although the problem usually disappears within 5 days, a single blister might be a major problem in competitive sports or in a wilderness setting. Military training and combat effectiveness might also be compromised by foot blisters. This study sought to reveal the distribution of plantar shear forces in athletic individuals and its relevance to foot blisters.
Methods: Three groups of 11 participants each were studied: blister, adult control, and pediatric control. A custom-built shear and pressure platform was used to collect plantar pressure and shear data while the participants walked over the device. Data were analyzed with repeated-measures analysis of variance.
Results: The blister group had significantly increased pressure and shear stress magnitudes compared with the other groups, although no significant group-site interaction was found. The shear-time integral values were increased approximately 50% at specific sites of the athletic feet, suggesting that contact time may play a role in blister formation.
Conclusions: The biomechanical interaction on the plantar surface of a blister-prone person is different from that of individuals who are less prone to the problem. (J Am Podiatr Med Assoc 100(2): 116–120, 2010)