Cast Loosening in Fracture Management

Need Statement: There is a need for a method to reduce the loosening of casts that occurs due to shrinkage of padding and atrophy of muscle to improve the healing of fractures, prevent the need for recasting, and reduce time and costs to patients and physicians.

Project Summary: Approximately 887,679 hospitalizations result each year from fractures in the U.S. alone. Current casting methods are inexpensive but also ineffective. Most casts utilize either fiberglass or plaster to form a rigid structure, paired with cotton or gore-tex padding in order to stabilize the fractured bone. After bone fracture, severe swelling of the extremity can occur. Once this swelling subsides the cast cannot conform to the smaller shape of the extremity. Additionally, after long periods of immobilization muscle atrophy can cause the cast to loosen. This loosening causes slippage, skin irritation, loss of fracture stability, and even premature removal of casts by patients, all of which can slow or prevent proper healing.
The cotton padding that is currently used can contribute to loosening because after time it can compress due to moisture, from outside water or from sweat, and it can pick up grime causing irritation of the skin. Gore-tex padding is designed to be “waterproof”, however it still compresses significantly over time and is not immune to causing skin irritation or developing a smell. Currently the standard of care is to recast the patient about 3 weeks after the initial cast was applied. Physicians only receive one payment for this entire process, usually including at least one recasting. Additionally, depending on the severity of swelling and the type of fracture, it may not even be possible to cast until several days after the injury due to the risk of compartment syndrome if swelling increases at all and the cast becomes too tight. A new cast design that has the ability to adapt its fit throughout the treatment process could eliminate this need for recasting saving time and money on both the patient and physician end. The potential cost savings as well as the value added to both customers and physicians suggest a solution would be commercially viable.This newly envisioned cast design could take on a number of different forms, however due to the understanding of both the need and current solutions and the relative simplicity of the current cast designs the project seems very technically feasible.