title: Contributory factors to unsteadiness during walking up and down stairs in patients with diabetic peripheral neuropathy.
abstract: OBJECTIVE
  Although patients with diabetic peripheral neuropathy (DPN) are more likely to fall than age-matched controls, the underlying causative factors are not yet fully understood. This study examines the effects of diabetes and neuropathy on strength generation and muscle activation patterns during walking up and down stairs, with implications for fall risk.
  
  
  METHODS
  Sixty-three participants (21 patients with DPN, 21 diabetic controls, and 21 healthy controls) were examined while walking up and down a custom-built staircase. The speed of strength generation at the ankle and knee and muscle activation patterns of the ankle and knee extensor muscles were analyzed.
  
  
  RESULTS
  Patients with neuropathy displayed significantly slower ankle and knee strength generation than healthy controls during stair ascent and descent (P < 0.05). During ascent, the ankle and knee extensor muscles were activated significantly later by patients with neuropathy and took longer to reach peak activation (P < 0.05). During descent, neuropathic patients activated the ankle extensors significantly earlier, and the ankle and knee extensors took significantly longer to reach peak activation (P < 0.05).
  
  
  CONCLUSIONS
  Patients with DPN are slower at generating strength at the ankle and knee than control participants during walking up and down stairs. These changes, which are likely caused by altered activations of the extensor muscles, increase the likelihood of instability and may be important contributory factors for the increased risk of falling. Resistance exercise training may be a potential clinical intervention for improving these aspects and thereby potentially reducing fall risk.
authors.affiliation: Manchester Metropolitan University, Manchester, U.K. j.handsaker@mmu.ac.uk.
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Handsaker
authors.affiliation: Manchester Metropolitan University, Manchester, U.K.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Brown
authors.affiliation: University of Manchester, Manchester, U.K.
authors.forename: Frank L
authors.initials: FL
authors.lastname: Bowling
authors.affiliation: Manchester Metropolitan University, Manchester, U.K.
authors.forename: Glen
authors.initials: G
authors.lastname: Cooper
authors.affiliation: Manchester Metropolitan University, Manchester, U.K.
authors.forename: Constantinos N
authors.initials: CN
authors.lastname: Maganaris
authors.affiliation: University of Manchester, Manchester, U.K.
authors.forename: Andrew J M
authors.initials: AJ
authors.lastname: Boulton
authors.affiliation: Manchester Metropolitan University, Manchester, U.K.
authors.forename: Neil D
authors.initials: ND
authors.lastname: Reeves
mesh_terms: D000368:Aged; D000843:Ankle Joint / Q000473:pathology; D016022:Case-Control Studies; D003920:Diabetes Mellitus / Q000503:physiopathology*; D003929:Diabetic Neuropathies / Q000503:physiopathology*; D015444:Exercise / Q000502:physiology; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000473:pathology; D008297:Male; D008875:Middle Aged; D016138:Walking / Q000502:physiology*