The prevention of diabetic foot ulceration: how biomechanical research informs clinical practice

ABSTRACT Background Implementation of interprofessional clinical guidelines for the prevention of neuropathic diabetic foot ulceration has demonstrated positive effects regarding ulceration and amputation rates. Current foot care recommendations are primarily based on research regarding the prevention of ulcer recurrence and focused on reducing the magnitude of plantar stress (pressure overload). Yet, foot ulceration remains to be a prevalent and debilitating consequence of Diabetes Mellitus. There is limited evidence targeting the prevention of first-time ulceration, and there is a need to consider additional factors of plantar stress to supplement current guidelines. Objectives The first purpose of this article is to discuss the biomechanical theory underpinning diabetic foot ulcerations and illustrate how plantar tissue underloading may precede overloading and breakdown. The second purpose of this commentary is to discuss how advances in biomechanical foot modeling can inform clinical practice in the prevention of first-time ulceration. Discussion Research demonstrates that progressive weight-bearing activity programs to address the frequency of plantar stress and avoid underloading do not increase ulceration risk. Multi-segment foot modeling studies indicate that dynamic foot function of the midfoot and forefoot is compromised in people with diabetes. Emerging research demonstrates that implementation of foot-specific exercises may positively influence dynamic foot function and improve plantar stress in people with diabetes. Conclusion Continued work is needed to determine how to best design and integrate activity recommendations and foot-specific exercise programs into the current interprofessional paradigm for the prevention of first-time ulceration in people with Diabetes Mellitus.

Plantar pressure distribution patterns during gait in diabetic neuropathy patients with a history of foot ulcers

OBJECTIVE: To investigate and compare the influence of a previous history of foot ulcers on plantar pressure variables during gait of patients with diabetic neuropathy. INTRODUCTION: Foot ulcers may be an indicator of worsening diabetic neuropathy. However, the behavior of plantar pressure patterns over time and during the progression of neuropathy, especially in patients who have a clinical history of foot ulcers, is still unclear. METHODS: Subjects were divided into the following groups: control group, 20 subjects; diabetic neuropathy patients without foot ulcers, 17 subjects; and diabetic neuropathy patients with at least one healed foot ulcer within the last year, 10 subjects. Plantar pressure distribution was recorded during barefoot gait using the Pedar-X system. RESULTS: Neuropathic subjects from both the diabetic neuropathy and DNU groups showed higher plantar pressure than control subjects. At midfoot, the peak pressure was significantly different among all groups: control group (139.4±76.4 kPa), diabetic neuropathy (205.3±118.6 kPa) and DNU (290.7±151.5 kPa) (p=0.008). The pressure-time integral was significantly higher in the ulcerated neuropathic groups at midfoot (CG: 37.3±11.4 kPa.s; DN: 43.3±9.1 kPa.s; DNU: 68.7±36.5 kPa.s; p=0.002) and rearfoot (CG: 83.3±21.2 kPa.s; DN: 94.9±29.4 kPa.s; DNU: 102.5±37.9 kPa.s; p=0.048). CONCLUSION: A history of foot ulcers in the clinical history of diabetic neuropathy subjects influenced plantar pressure distribution, resulting in an increased load under the midfoot and rearfoot and an increase in the variability of plantar pressure during barefoot gait. The progression of diabetic neuropathy was not found to influence plantar pressure distribution.

Ulceras venosas de miembros inferiores: fisiopatogenia, Manifestaciones clinicas y tratamiento / Venous leg ulcers

Muchos médicos encuentran que las úlceras venosas es una patología de difícil manejo. Esta enfermedad no es rara y su tratamiento varía según las características de la úlcera y del paciente. Presentamos una revisión de la literatura en la que se incluyeron aspectos de su fisiopatogenia, semiología, diagnóstico y tratamiento

Factores de crecimiento en el tratamiento de úlceras en pacientes diabéticos. Mitos y realidades / Growth factors in treatment of foot ulcers in diabetic patients. Myths and realities

Las úlceras neuropáticas de los pies en los pacientes diabéticos se pueden presentar hasta en 10 por ciento de ellos y tienen una recurrencia a cinco años del 70 por ciento. La infección, isquemia y trauma repetido pueden contribuir al desarrollo de úlceras crónicas en este grupo de pacientes que además presentan como característica alteraciones en los procesos básicos de la cicatrización. Una de estas alteraciones es la disminución de factores de crecimiento de las úlceras crónicas. Se han identificado diversos factores de crecimiento en la reparación de tejidos entre los cuales se encuentra el factor de crecimiento epidérmico, factor de crecimiento transformante beta, factor de crecimiento de fibroblastos, factor de crecimiento derivado de plaquetas y el factor de crecimiento tipo insulina. Estos factores se han estudiado en úlceras de pacientes diabéticos de diferentes etiologías, sin embargo, los mejores resultados han sido observados en úlceras neuropáticas.Algunos de estos como el factor de crecimiento derivado de plaquetas ha sido estudiado incluso en ensayos clínicos fase III y aceptados por la FDA para su aplicación clínica en este tipo de padecimientos. Otros como el factor de crecimiento epidermoide ha demostrado ser útil o incluso superior a otros, sin embargo, aún son pocos los estudios clínicos controlados que demuestran lo anterior. El uso de factores de crecimiento en las úlceras neuropáticas y crónicas de diabéticos es una alternativa más en el manejo de esta compleja patología.

Mechanics of tarsal disintegration and plantar ulcers in leprosy by stress analysis in three dimensional foot models.

This paper describes three dimensional two arch models of feet of a normal subject and two leprosy subjects, one in the early stage and the other in the advanced stage of tarsal disintegration, used for analysis of skeletal and plantar soft tissue stresses by finite element technique using NISA software package. The model considered the foot geometry (obtained from X-rays), foot bone, cartilages, ligaments, important muscle forces and sole soft tissue. The stress analysis is carried out for the foot models simulating quasi-static walking phases of heel-strike, mid-stance and push-off. The analysis of the normal foot model shows that highest stresses occur at push-off over the dorsal central part of lateral and medial metatarsals and dorsal junction of calcaneus and cuboid and neck of talus. The skeletal stresses, in early state leprosy with muscle paralysis and in the advanced stage of tarsal distintegration (TD), are higher than those for the normal foot model, by 24% to 65% and 30% to 400%, respectively. The vertical stresses in the soft tissue at the foot-ground interface match well with experimentally measured foot pressures and for the normal and leprosy subjects they are the highest in the push-off phase. In the leprosy subject with advanced TD, the highest soft tissue stresses and shear stresses (about three times the normal value) occur in push-off phase in the scar tissue region. The difference in shear stresses between the sole and the adjacent soft tissue layer in the scar tissue for the same subject is about three times the normal value. It is concluded that the high bone stresses in leprosy may be responsible for tarsal distintegration when the bone mechanical strength decreases due to osteoporosis and the combined effect of high value of footsole vertical stresses, shear stresses and the relative shear stresses between two adjacent soft tissue layers may be responsible for plantar ulcers in the neuropathic leprosy feet.

Protective sensibility--its monofilament nylon threshold equivalents in leprosy patients.

An attempt has been made to definite the levels of "protective sensibility" in terms of perception thresholds to monofilament nylon induced touch/pressure stimuli. Certain problems were observed while interpreting the observations. There appears to be a range of threshold values instead of a clear cut-off point. We suggest that a monofilament nylon stimulus two times the normal threshold value for that patient be taken as cut-off point. This will make the observations of Birke and Sims (1986) and Hammond and Klenerman (1987) reasonable without having any need to exclude the cases who defy the boundaries laid by them. Since the genesis of plantar ulcer is multifactorial, it appears logical to include all patients who have a certain degree of hypoaesthesia, for special ulcer care program. The likely problems while using monofilament nylons in the field and their possible solutions have also been outlined.

Tratamiento del pie diabético con preparación que contiene factores de crecimiento / Treatment of diabetic foot ulcers with topical growth factor - preparation

Las úlceras crónicas en los pacientes con pie diabético constituyen un problema de difícil tratamiento, el cual implica por lo general un costo elevado para el paciente y para las instituciones hospitalarias. Estudios previos han demostrado que preparados derivados de concentrados ricos en plaquetas aceleran significativamente la velocidad de cicatrización. Se presentan los resultados de un estudio abierto de 6 pacientes con diabetes mellitus tipo II y úlceras crónicas, resistentes a la cicatrización, que fueron tratados con una preparación derivada de concentrados plaquetarios; en cinco de los pacientes se logró promover la cicatrización de la úlcera, consiguiéndose la epitelización completa de la misma

Podometry: a critical evaluation of its use in Hansen's disease

O objetivo deste trabalho é avaliar a eficácia da podometria na prevençäo do mal perfurante plantar em pacientes hansenianos. Foram avaliados 13 pacientes hansenianos com comprometimento da sensibilidade táctil e dolorosa da planta do pé e 17 pacientes normais. Todos os pacientes foram submetidos à avaliaçäo estática através do podômetro. O sistema utilizado foi o podômetro comercial Midcapteur, constituído de uma plataforma para aquisiçäo dos dados analógos, capaz de registrar as pressöes segmentares aplicadas nos pés. Estes dados säo lidos num computador IBM/PC 386 compatível, que registra o mapeamento gráfico das pressöes desenvolvidas assim como calcula a distribuiçäo desta mesma pressäo nos 4 quadrantes do pé. Estes dados obtidos através da podometria estática foram comparados com a avaliaçäo clínica da sensibilidade táctil e dolorosa dos pés, nos pacientes hansenianos. Os resultados mostraram que o podômetro é bom método para se avaliar os pés com deficiência de sensibilidade em hanseníase e também como um método de avaliaçäo que ajuda na prevençäo do desenvolvimento do mal perfurante plantar: foi sensível na identificaçäo dos pontos de hiperpressäo nas áreas anestésicas e em regiöes anômalas, das assimetrias e na correlaçäo entre a presença de úlceras e hiperpressäo