title: Temperature as a predictive tool for plantar triaxial loading.
abstract: Diabetic foot ulcers are caused by moderate repetitive plantar stresses in the presence of peripheral neuropathy. In severe cases, the development of these foot ulcers can lead to lower extremity amputations. Plantar pressure measurements have been considered a capable predictor of ulceration sites in the past, but some investigations have pointed out inconsistencies when solely relying on this method. The other component of ground reaction forces/stresses, shear, has been understudied due to a lack of adequate equipment. Recent articles reported the potential clinical significance of shear in diabetic ulcer etiology. With the lack of adequate tools, plantar temperature has been used as an alternative method for determining plantar triaxial loading and/or shear. However, this method has not been previously validated. The purpose of this study was to analyze the potential association between exercise-induced plantar temperature increase and plantar stresses. Thirteen healthy individuals walked on a treadmill for 10 minutes at 3.2km/h. Pre and post-exercise temperature profiles were obtained with a thermal camera. Plantar triaxial stresses were quantified with a custom-built stress plate. A statistically significant correlation was observed between peak shear stress (PSS) and temperature increase (r=0.78), but not between peak resultant stress (PRS) and temperature increase (r=0.46). Plantar temperature increase could predict the location of PSS and PRS in 23% and 39% of the subjects, respectively. Only a moderate linear relationship was established between triaxial plantar stresses and walking-induced temperature increase. Future research will investigate the value of nonlinear models in predicting plantar loading through foot temperature.
authors.affiliation: University of North Texas Health Science Center, Fort Worth, TX, USA. Electronic address: Metin.Yavuz@unthsc.edu.
authors.forename: Metin
authors.initials: M
authors.lastname: Yavuz
authors.affiliation: University of North Texas Health Science Center, Fort Worth, TX, USA.
authors.forename: Ryan W
authors.initials: RW
authors.lastname: Brem
authors.affiliation: The University of Akron, Akron, OH, USA.
authors.forename: Brian L
authors.initials: BL
authors.lastname: Davis
authors.affiliation: Cooper University Hospital, Camden, NJ, USA.
authors.forename: Jalpa
authors.initials: J
authors.lastname: Patel
authors.affiliation: Kent State University College of Podiatric Medicine, Independence, OH, USA.
authors.forename: Abe
authors.initials: A
authors.lastname: Osbourne
authors.affiliation: VA Maryland Health Care System, Baltimore, MD, USA.
authors.forename: Megan R
authors.initials: MR
authors.lastname: Matassini
authors.affiliation: Swedish Medical Center, Seattle, WA, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Wood
authors.affiliation: Scripps Mercy Hospital-Kaiser Foundation Hospital, San Diego, CA, USA.
authors.forename: Irene O
authors.initials: IO
authors.lastname: Nwokolo
mesh_terms: D000328:Adult; D017719:Diabetic Foot / Q000503:physiopathology*; D005260:Female; D005528:Foot / Q000503:physiopathology*; D006801:Humans; D008297:Male; D011312:Pressure; D013314:Stress, Mechanical; D013696:Temperature; D016138:Walking / Q000502:physiology*; D055815:Young Adult
keywords: Diabetes; Plantar pressure; Plantar shear; Thermography; Ulcer