title: Static and Dynamic Predictors of Foot Progression Angle in Individuals with and without Diabetes Mellitus and Peripheral Neuropathy.
abstract: BACKGROUND
  Foot progression angle (FPA) is a predictor of elevated regional plantar stresses and loads, which are indicators of dermal injury risk in individuals with diabetes mellitus and peripheral neuropathy (DMPN). FPA accounts for 15-45% of the variance in plantar stresses and loads in adults with DMPN. However, the biomechanical factors underlying an "out-toeing" gait pattern in this clinical population have not been examined. The primary purpose of this study was to identify static and dynamic predictors of foot progression angle magnitude in adults with and without DMPN.
  
  
  METHODS
  Thirty-three adults with and 12 adults without diabetes mellitus participated. Hip rotation, ankle dorsiflexion, and resting calcaneal stance position were measured using a standard goniometer. Kinematic and kinetic data were collected during walking.
  
  
  CONCLUSIONS
  Static predictor variables did not significantly predict foot progression angle magnitude using multiple regression analysis. Of the dynamic predictor variables, thigh and shank lateral rotation accounted for 37% of foot progression angle variance (p<.01).
  
  
  CONCLUSIONS
  Our results show that dynamic measures of external rotation of proximal segments (thigh, shank) during gait are strong predictors of foot progression angle. Static measures of limited joint mobility and joint position do not predict foot progression angle. These findings suggest that targeting the thigh and shank rotation using verbal or tactile cueing may be a potential strategy when trying to alter walking movement patterns towards decreasing external (lateral) FPA to minimize risk of elevated regional plantar stresses in adults with DMPN at risk for ulceration.
authors.affiliation: Department of Physical Therapy and Rehabilitation Science, University of Iowa, USA.
authors.forename: Ericka N
authors.initials: EN
authors.lastname: Merriwether
authors.affiliation: Program in Physical Therapy, Washington University School of Medicine St. Louis, USA.
authors.forename: Mary K
authors.initials: MK
authors.lastname: Hastings
authors.affiliation: Program in Physical Therapy, Washington University School of Medicine St. Louis, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Mueller
authors.affiliation: Program in Physical Therapy, Washington University School of Medicine St. Louis, USA.
authors.forename: Kathryn L
authors.initials: KL
authors.lastname: Bohnert
authors.affiliation: Department of Psychology, Washington University in St. Louis, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Strube
authors.affiliation: Program in Physical Therapy, Washington University School of Medicine St. Louis, USA.
authors.forename: Darrah R
authors.initials: DR
authors.lastname: Snozek
authors.affiliation: Program in Physical Therapy, Washington University School of Medicine St. Louis, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Sinacore
keywords: Diabetes; Foot progression angle; Gait; Goniometry; Lower extremity rotation; kinematics