Pressure relief and load redistribution by custom-made insoles in diabetic patients with neuropathy and foot deformity

Bus, Sicco A.<sup>1</sup>; Ulbrecht, Jan S.<sup>2</sup>; Cavanagh, Peter R.<sup>3</sup>

Affiliations

¹Department of Internal Medicine, Academic Medical Center, University of Amsterdam, 1100 DE Amsterdam, The Netherlands

²Departments of Biobehavioral Health and Medicine, Pennsylvania State University, University Park, PA 16802, USA

³Department of Biomedical Engineering/ND20, Lerner Research Institute, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH44195, USA

Abstract

Objective: To study the effects of custom-made insoles on plantar pressures and load redistribution in neuropathic diabetic patients with foot deformity.

Design: Cross-sectional.

Background: Although custom-made insoles are commonly prescribed to diabetic patients, little quantitative data on their mechanical action exists.

Methods: Regional in-shoe peak pressures and force-time integrals were measured during walking in the feet of 20 neuropathic diabetic subjects with foot deformity who wore flat or custom-made insoles. Twenty-one feet with elevated risk for ulceration at the first metatarsal head were analysed. Load redistribution resulting from custom-made insoles was assessed using a new load-transfer algorithm.

Results: Custom-made insoles significantly reduced peak pressures and force-time integrals in the heel and first metatarsal head regions; pressures and integrals were significantly increased in the medial midfoot region compared with flat insoles. Custom-made insoles successfully reduced pressures in and integrals at the first metatarsal head in 7/21 feet, were moderately successful in another seven, but failed in the remaining seven. Load transfer was greatest from the lateral heel to the medial midfoot regions.

Conclusions: Custom-made insoles were more effective than flat insoles in off-loading the first metatarsal head region, but with considerable variability between individuals. Most off-loading occurred in the heel (not a region typically at risk). The load transfer algorithm effectively analyses custom-made-insole action.

Relevance: Because similar insole modifications apparently exert different effects in different patients, a comprehensive evaluation of custom designs using in-shoe pressure measurement should ideally be conducted before dispensing insoles to diabetic patients with neuropathy and foot deformity.

Links

DOI: 10.1016/j.clinbiomech.2004.02.010

PubMed: 15234488

WoS: 000222845500012

History

Received: 2003-05-22

Accepted: 2004-02-19

Cited Works (1)

Year	Entry
1987	Cavanagh PR, Rodgers MM, Iiboshi A. Pressure distribution under symptom-free feet during barefoot standing. Foot Ankle Int. April 1987;7(5):262-278.

Cited By (6)

Year	Entry
2006	Goske S, Erdemir A, Petre M, Budhabhatti S, Cavanagh PR. Reduction of plantar heel pressures: insole design using finite element analysis. J Biomech. 2006;39(13):2363-2370.
2007	Budhabhatti SP, Erdemir A, Petre M, Sferra J, Donley B, Cavanagh PR. Finite element modeling of the first ray of the foot: a tool for the design of interventions. J Biomech Eng. 2007;129(5):750-756.
2008	Actis RL, Ventura LB, Lott DJ, Smith KE, Commean PK, Hastings MK, Mueller MJ. Multi-plug insole design to reduce peak plantar pressure on the diabetic foot during walking. Med Biol Eng Comput. 2008;46(4):363-371.
2007	Budhabhatti SP. Enhanced Plantar Pressure Relief Using Computational Modeling: A Tool for Assisting Clinical Decision Making [PhD thesis]. Cleveland State University; December 2007.
2005	Cheung TMJ. Development of Knowledge-Based Criteria for Designing Foot Orthoses [PhD thesis]. Hong Kong Polytechnic University; October 2005.
2007	Lott DJ. Effects of Stress Application on the Soft Tissues of the Neuropathic Foot [PhD thesis]. St. Louis, MO: Washington University in St. Louis; May 2007.