DESIGN OF A LOWER LIMB SUPPORT SYSTEM FOR THE APPLICATION OF COMPRESSION BANDAGES

Abstract

The objective of this project is to design and prototype a device for the Winnipeg Regional Health Authority/Shared Health (WRHA/SH) to assist clinical providers with the application of two-layered compression bandages to a patient’s lower limb(s), in a hospital or homecare settings. Two-layer compression bandages are used to reduce the swelling in the limb(s) of patients with edema. Applying these bandages to a patient’s lower limb(s) can be challenging for the clinical provider due to the weight and size of the limb. In addition to the final design report, other requirements include preliminary engineering drawings, a bill of materials, a CAD model of the design, a cost estimate for the design, user instructions and a demonstrational prototype are required. The team generated eighteen preliminary concepts with sketches based on the customer needs and technical specifications. The top five concepts were selected using engineering intuition, a concept screening matrix and a weighted decision matrix. After further analysis and CAD models were created, the client selected two designs which moved to the detailed design phase: the Scissor Wedge and the Roller. Further improvements were made to both designs. The improved Roller and Scissor Wedge designs were presented to the client. The client and team selected the improved Scissor Wedge, renamed Lift Pill for the final design. The Lift Pill is an assistive device which lifts the patient’s lower thigh and upper calf using two independent supports. The device has a small closed profile and can be positioned under the patient’s knee with minimal lifting of the leg. The thigh-side support is raised using a rachet, which turn a lead screw inside the device and raises two linkages in a linear motion. The calf-side support lifts the patient’s lower leg using two gas springs, working simultaneously. The Lift Pill meets 80% of the clients target specifications. The device is designed to support a leg weighing up to 40 kg and is stable on soft surfaces such as a mattress. The Lift Pill is a Class I device according to Health Canada medical device classification. The Lift Pill is also portable, measuring 32.5 cm...