title: Shoulder load during synchronous handcycling and handrim wheelchair propulsion in persons with paraplegia.
abstract: OBJECTIVE
  To compare the shoulder load during handcycling and wheelchair propulsion under similar conditions of external power in persons with spinal cord injury.
  
  
  METHODS
  Cross-sectional.
  
  
  METHODS
  Eight men with spinal cord injury.
  
  
  METHODS
  Kinetics and kinematics were measured during handbike and wheelchair propulsion at 25, 35, 45 and 55 W on a treadmill. Shoulder load (glenohumeral contact forces, relative muscle forces) was calculated with the Delft Shoulder and Elbow Model.
  
  
  RESULTS
  At all power output levels, glenohumeral contact forces were significantly lower during handcycling compared with wheelchair propulsion (p < 0.001). At 55 W, the mean glenohumeral contact force was 345 N for hand-cycling, whereas it was 585 N for wheelchair propulsion. Also, relative muscle forces were lower during handcycling. The largest differences between handbike and wheelchair propulsion were found in the supraspinatus (4.5% vs. 20.7%), infraspinatus (3.7% vs. 16.5%) and biceps (5.0% vs. 17.7%).
  
  
  CONCLUSIONS
  Due to continuous force application in hand-cycling, shoulder load was lower compared with wheelchair propulsion. Furthermore, muscles that are prone to overuse injuries were less stressed during handcycling. Therefore, handcycling may be a good alternative for outdoor mobility and may help prevent overuse injuries of the shoulder complex.
authors.affiliation: Swiss Paraplegic Research, Nottwil, Switzerland. ursina.arnet@paranet.ch
authors.forename: Ursina
authors.initials: U
authors.lastname: Arnet
authors.forename: Stefan
authors.initials: S
authors.lastname: van Drongelen
authors.forename: Anke
authors.initials: A
authors.lastname: Scheel-Sailer
authors.forename: Lucas H V
authors.initials: LH
authors.lastname: van der Woude
authors.forename: DirkJan H E J
authors.initials: DH
authors.lastname: Veeger
mesh_terms: D000328:Adult; D001642:Bicycling; D001696:Biomechanical Phenomena; D003430:Cross-Sectional Studies; D005080:Exercise Test; D006801:Humans; D008124:Locomotion; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000502:physiology*; D010264:Paraplegia / Q000209:etiology; D012782:Shoulder / Q000502:physiology*; D012785:Shoulder Joint / Q000502:physiology; D013119:Spinal Cord Injuries / Q000150:complications; D013647:Task Performance and Analysis; D014910:Wheelchairs