The effects of in-socket air pressure on residuum volume

  • Research type

    Research Study

  • Full title

    The effects of in-socket air pressure on short term changes in residuum volume, pistoning, gait kinematics, and comfort: A comparison between active and passive systems

  • IRAS ID

    195126

  • Contact name

    Laurence Kenney

  • Contact email

    L.P.J.Kenney@salford.ac.uk

  • Sponsor organisation

    The University of Salford

  • Clinicaltrials.gov Identifier

    N/A, N/A

  • Duration of Study in the UK

    0 years, 5 months, 6 days

  • Research summary

    Amputee subjects often complain of problems resulting from the change in volume of their residual limb over the course of a day. If the limb volume reduces, the socket fit becomes poorer and pistoning (displacement of the socket relative to the limb) can result, leading to discomfort, changes to gait and damage to the residuum tissue. One factor which research suggests may impact on limb volume changes with time, is the air pressure within the socket. Recently, 2 small studies have demonstrated that, by using a vacuum pump attached to the socket to achieve a below-atmosphere socket pressure while walking, limb volume may be better maintained. However, such devices are expensive and require specialist fitting. This study will explore whether, by using a socket with a large void at the distal end, in-socket pressure fluctuations during gait may be reduced, in turn impacting on residual volume changes. Specifically, the primary focus of the study will be to investigate the effects of in-socket air pressure on short term changes (within-day) in residuum volume, pistoning, gait kinematics, and comfort. We will investigate the impact of walking with 3 different types of socket on:
    • Maintenance of residuum volume;
    • Pistoning;
    • Gait kinematics and kinetics and;
    • Comfort.
    The three types of socket are:
    - Normal geometry socket
    - Normal geometry socket with a vacuum pump
    - Socket with air void at the distal end
    The secondary objective of this study is to explore the potential to assess pistoning using an air pressure sensor.

    Ten participants with unilateral limb loss at the trans-tibial level will be recruited to the study. All participants will have self-reported problems with residual limb volume fluctuations, or pistoning. Participants will be required to visit the University of Salford on two occasions; once for socket fitting and once for gait assessment.

  • REC name

    HSC REC A

  • REC reference

    16/NI/0151

  • Date of REC Opinion

    29 Jul 2016

  • REC opinion

    Further Information Favourable Opinion