title: Biomechanical contributions of the trunk and upper extremity in discrete versus cyclic reaching in survivors of stroke.
abstract: BACKGROUND
  Stroke rehabilitation interventions and assessments incorporate discrete and/or cyclic reaching tasks, yet no biomechanical comparison exists between these 2 movements in survivors of stroke.
  
  
  OBJECTIVE
  To characterize the differences between discrete (movements bounded by stationary periods) and cyclic (continuous repetitive movements) reaching in survivors of stroke.
  
  
  METHODS
  Seventeen survivors of stroke underwent kinematic motion analysis of discrete and cyclic reaching movements. Outcomes collected for each side included shoulder, elbow, and trunk range of motion (ROM); peak velocity; movement time; and spatial variability at target contact.
  
  
  RESULTS
  Participants used significantly less shoulder and elbow ROM and significantly more trunk flexion ROM when reaching with the stroke-affected side compared with the less-affected side (P < .001). Participants used significantly more trunk rotation during cyclic reaching than discrete reaching with the stroke-affected side (P = .01). No post hoc differences were observed between tasks within the stroke-affected side for elbow, shoulder, and trunk flexion ROM. Peak velocity, movement time, and spatial variability were not different between discrete and cyclic reaching in the stroke-affected side.
  
  
  CONCLUSIONS
  Survivors of stroke reached with altered kinematics when the stroke-affected side was compared with the less-affected side, yet there were few differences between discrete and cyclic reaching within the stroke-affected side. The greater trunk rotation during cyclic reaching represents a unique segmental strategy when using the stroke-affected side without consequences to end-point kinematics. These findings suggest that clinicians should consider the type of reaching required in therapeutic activities because of the continuous movement demands required with cyclic reaching.
authors: Physical Therapy and Rehabilitation Science Department, University of Maryland School of Medicine, Baltimore, Maryland.
authors: Crystal L
authors: CL
authors: Massie
authors: Occupational Therapy Department, Colorado State University, Fort Collins, Colorado.
authors: Matthew P
authors: MP
authors: Malcolm
authors: Occupational Therapy Department, Colorado State University, Fort Collins, Colorado.
authors: David P
authors: DP
authors: Greene
authors: Health and Exercise Science Department, Colorado State University, Fort Collins, Colorado.
authors: Raymond C
authors: RC
authors: Browning
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007511:Ischemia / Q000150:complications; D008297:Male; D008875:Middle Aged; D016059:Range of Motion, Articular / Q000502:physiology*; D013223:Statistics as Topic; D020521:Stroke / Q000209:etiology / Q000401:mortality*; D000071939:Stroke Rehabilitation; D060726:Torso / Q000503:physiopathology*; D034941:Upper Extremity / Q000503:physiopathology*
keywords: kinematic motion analysis; motor control; rehabilitation