Radial Volume Device for Prosthetic Sockets

Life Sciences : Medical Devices

Available for licensing


  • Richard Crawford, Ph.D. , Mechanical Engineering
  • Meagan Vaughan , University of Texas at Austin
  • Gordon Bosker , University of Texas Health Science Center at San Antonio

Background/unmet need

For those with amputations, prostheses are important tools with which to perform many activities of daily living. Ideally, a prosthesis enables the user to function with the same freedom as a physically able person.

In spite of improvement made in understanding socket fit and refining manufacturing technology, the issue of greatest concern to amputees continues to be lack of proper fit and comfort in their socket.

Lack of comfort and proper fit can often be attributed to a change in the shape of the remaining limb that cannot be compensated for by existing prosthetic socket technology. Changes can include the increase or decrease in volume of the residual limb, in longitudinal or radial directions (or both), and are caused by a variety of factors such as weight gain/loss, atrophy, swelling, and normal growth.

A new design that will accommodate changes in residual limb volume and therefore improve comfort is the goal of this invention.

Invention Description

Researchers at The University of Texas at Austin are working on a device which includes radial prosthetic volume adjustment to accommodate changes in residual limb volume.
Based on a mechanism similar to that of a camera aperture, this invention relies on the rotation of a plate fixed to the distal end of a prosthetic socket to produce radial movement of sections of the prosthetic socket. Manufacture of this device is accomplished using common materials and hand tools.


  • Low cost application
  • Comfortable
  • Longer lifespan


  • Radial prosthetic volume adjustment
  • Simple manufacturing tools and skills
  • Can be incorporated into standard prosthetic socket design
  • Low cost

Market potential/applications

Prosthetic manufacturing companies; e.g., Ottobockus and Limbsinternational

Development Stage

Lab/bench prototype

IP Status

  • 1 U.S. patent application filed