title: Foot and ankle muscle strength in people with gout: A two-arm cross-sectional study.
abstract: BACKGROUND
  Foot and ankle structures are the most commonly affected in people with gout. However, the effect of gout on foot and ankle muscle strength is not well understood. The primary aim of this study was to determine whether differences exist in foot and ankle muscle strength for plantarflexion, dorsiflexion, inversion and eversion between people with gout and age- and sex-matched controls. The secondary aim was to determine whether foot and ankle muscle strength was correlated with foot pain and disability.
  
  
  METHODS
  Peak isokinetic concentric muscle torque was measured for ankle plantarflexion, dorsiflexion, eversion and inversion in 20 participants with gout and 20 matched controls at two testing velocities (30°/s and 120°/s) using a Biodex dynamometer. Foot pain and disability was measured using the Manchester Foot Pain and Disability Index (MFPDI).
  
  
  RESULTS
  Participants with gout demonstrated reduced muscle strength at both the 30°/s and 120°/s testing velocities for plantarflexion, inversion and eversion (P<0.05). People with gout also displayed a reduced plantarflexion-to-dorsiflexion strength ratio at both 30°/s and 120°/s (P<0.05). Foot pain and disability was higher in people with gout (P<0.0001) and MFPDI scores were inversely correlated with plantarflexion and inversion muscle strength at the 30°/s testing velocity, and plantarflexion, inversion and eversion muscle strength at the 120°/s testing velocity (all P<0.05).
  
  
  CONCLUSIONS
  People with gout have reduced foot and ankle muscle strength and experience greater foot pain and disability compared to controls. Foot and ankle strength reductions are strongly associated with increased foot pain and disability in people with gout.
authors.affiliation: School of Podiatry, Health & Rehabilitation Research Institute, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand. Electronic address: sarah.stewart@aut.ac.nz.
authors.forename: Sarah
authors.initials: S
authors.lastname: Stewart
authors.affiliation: Department of Physiotherapy, School of Rehabilitation & Occupation Studies, Faculty of Health & Environmental Sciences, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand.
authors.forename: Grant
authors.initials: G
authors.lastname: Mawston
authors.affiliation: School of Podiatry, Health & Rehabilitation Research Institute, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand.
authors.forename: Lisa
authors.initials: L
authors.lastname: Davidtz
authors.affiliation: Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Department of Rheumatology, Auckland District Health Board, P.O. Box 92189, Auckland, New Zealand.
authors.forename: Nicola
authors.initials: N
authors.lastname: Dalbeth
authors.affiliation: Department of Biostatistics & Epidemiology, School of Public Health & Psychosocial Studies, Faculty of Health and Environmental Sciences, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand; Health Intelligence and Informatics, Ko Awatea, Counties Manukau Health, Private Bag 93311, Auckland 1640, New Zealand.
authors.forename: Alain C
authors.initials: AC
authors.lastname: Vandal
authors.affiliation: School of Podiatry, Health & Rehabilitation Research Institute, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand.
authors.forename: Matthew
authors.initials: M
authors.lastname: Carroll
authors.affiliation: School of Podiatry, Health & Rehabilitation Research Institute, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand.
authors.forename: Trish
authors.initials: T
authors.lastname: Morpeth
authors.affiliation: School of Podiatry, Health & Rehabilitation Research Institute, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand; School of Health Professions, University of Brighton, Darley Road, Eastbourne BN20 7UR, Brighton, United Kingdom.
authors.forename: Simon
authors.initials: S
authors.lastname: Otter
authors.affiliation: School of Podiatry, Health & Rehabilitation Research Institute, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand.
authors.forename: Keith
authors.initials: K
authors.lastname: Rome
mesh_terms: D000328:Adult; D000368:Aged; D000842:Ankle / Q000503:physiopathology*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D005528:Foot / Q000503:physiopathology*; D006073:Gout / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D053581:Muscle Strength Dynamometer; D018908:Muscle Weakness / Q000503:physiopathology*; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010146:Pain / Q000503:physiopathology; D019415:Torque
keywords: Ankle; Biodex dynamometry; Gout; Torque