title: Assessing changes in subjective and objective function from pre- to post-knee arthroplasty using the Cardiff Dempster-Shafer theory classifier.
abstract: The purpose of this study is to assess changes in subjective and objective function from pre- to post-knee arthroplasty (KA) using a combined classifier technique. Twenty healthy adults (50-80 years) and 31 KA patients (39-81 years) were studied (4 weeks pre- and 6 months post-KA). Questionnaire measures of subjective pain, joint stability, activity and function were collected. Objective functional assessment included goniometry, ultrasound imaging and 3-D motion analysis/inverse modelling of gait and sit-stand. An optimal set of variables were used to classify function using the Cardiff Dempster-Shafer theory (DST) method. Out of sample accuracy of the classifiers ranged between 90% and 94% for segregating healthy individuals and pre-KA patients. Post-KA subjective function improved with 74% classified as healthy. However, there was minimal improvement in objective measures (23% classified as healthy). The novel use of Cardiff DST segregated KA patients from healthy individuals and estimated changes in function from pre- to post-surgery. KA patients had improved pain and function post-operation but objective knee joint measures remained different to healthy individuals.
authors.affiliation: a Bioengineering Science Research Group, School of Engineering Sciences, University of Southampton , Southampton , UK.|b Faculty of Health Sciences, University of Southampton , Southampton , UK.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Worsley
authors.affiliation: c Cardiff School of Engineering, Cardiff University , Cardiff , UK.|d Arthritis Research UK Biomechanics and Bioengineering Centre, Cardiff University , Cardiff , UK.
authors.forename: Gemma
authors.initials: G
authors.lastname: Whatling
authors.affiliation: a Bioengineering Science Research Group, School of Engineering Sciences, University of Southampton , Southampton , UK.
authors.forename: David
authors.initials: D
authors.lastname: Barrett
authors.affiliation: c Cardiff School of Engineering, Cardiff University , Cardiff , UK.|d Arthritis Research UK Biomechanics and Bioengineering Centre, Cardiff University , Cardiff , UK.
authors.forename: Cathy
authors.initials: C
authors.lastname: Holt
authors.affiliation: b Faculty of Health Sciences, University of Southampton , Southampton , UK.|e Arthritis Research UK Centre for Sport, Exercise and Osteoarthritis , Southampton , UK.
authors.forename: Maria
authors.initials: M
authors.lastname: Stokes
authors.affiliation: a Bioengineering Science Research Group, School of Engineering Sciences, University of Southampton , Southampton , UK.|f Medical Device Research Institute, Flinders University , Adelaide , Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: Taylor
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D000886:Anthropometry; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D016002:Discriminant Analysis; D005260:Female; D005684:Gait; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000601:surgery; D025341:Principal Component Analysis
keywords: classification; clinical outcomes; function; gait; knee arthroplasty