title: Study of the effect of composition and construction of material on sub-bandage pressure during dynamic loading of a limb in vitro.
abstract: BACKGROUND
  Internal stress in a compression bandage wrapped over a limb in vitro is expected to reduce over time because of fatigue which may occur due to repetitive and prolonged variations in the extension of the bandage during posture change and exercise. This phenomenon may cause significant variation in the sub-bandage pressure over time.
  
  
  OBJECTIVE
  To examine the effect of composition and construction of material on the sub-bandage pressure variation over time in the dynamic state of a limb in the laboratory.
  
  
  METHODS
  Yarns comprising fibers of polyester, viscose, cotton and elastomeric yarn were used to prepare different knitted bandage samples having varying thread densities in the structure. A leg-segment prototype was used for the measurement of the interface pressure over a mannequin limb to analyse different bandages under similar dynamic conditions.
  
  
  RESULTS
  The pressure drop in the dynamic state of the mannequin limb was greater than that in the static state. The mean pressure drop in 2 h in the dynamic state was greater by >30% for bandages made of pure cotton or viscose yarns than for bandages having elastomeric yarns in their structure. At the same applied tension, increasing the number of yarns per unit length in the bandage structure resulted in a smaller drop in pressure in the dynamic mode.
  
  
  CONCLUSIONS
  Elastomeric yarn improves the elasticity and fatigue resistance of the bandage. Therefore, these yarns should be used in bandages to obtain sustained compression effects under dynamic conditions.
authors.affiliation: Department of Textile Technology, IIT Delhi, New Delhi, India. bipiniitd18@gmail.com
authors.forename: Bipin
authors.initials: B
authors.lastname: Kumar
authors.forename: Apurba
authors.initials: A
authors.lastname: Das
authors.forename: R
authors.initials: R
authors.lastname: Alagirusamy
mesh_terms: D058128:Compression Bandages; D005121:Extremities / Q000098:blood supply*; D006801:Humans; D008953:Models, Anatomic; D011312:Pressure; D013314:Stress, Mechanical; D014652:Vascular Diseases / Q000628:therapy*