“Edison represents the next step in Orthocare Innovations' advances in adaptive prosthetics systems,” commented Orthocare Chief Technology Officer David Boone, CP, MPH, PhD. “We looked hard at the drawbacks of existing elevated vacuum suspension systems, and identified two key areas for improvement: noise reduction, and automatic suspension adjustment across a full range of functional activities.”

Orthocare’s Galileo functional assessment system documents how amputees function, and it is clear that they change their activities constantly. Edison automatically adjusts the elevated vacuum to the user’s functional needs. After turning Edison on each morning, patients go about their day feeling the benefits of elevated vacuum, but without hearing the pump or needing to adjust the unit. There is no need for the user to manually make a change that will have to be adjusted again a few minutes later, as activity changes again.

Secure vacuum suspension of a prosthesis requires a range of values, from zero when sitting and standing, to several inches of mercury when running. Elevating vacuum beyond the minimum functional level needed does not improve suspension, and can cause problems. Every additional inch of mercury of elevated vacuum provides about another three and a half pounds of suspension force in an average transtibial prosthesis. Normal healthy tissue requires changing levels of contact pressure, to allow skin perfusion after periods of high pressure have created localized ischemia. Edison allows the prosthesis system to adapt pressure in a more physiologic way, significantly reducing the likelihood of tissue trauma from constant forces being applied to the residual limb. Edison adaptive suspension maintains optimal levels as determined by the prosthetist, allowing the patient both to sit comfortably and undertake vigorous activities with confidence.

Edison is self-contained within and around the tube clamp and pylon volume normally wasted in an endoskeletal prosthesis. This saves weight and creates a clean finish, with no additional boxes or controls strapped on the outside of the prosthesis.

Orthocare intends for these features to address segments of the market that may not currently benefit from elevated vacuum. Patients with diabetes or peripheral vascular disease may not tolerate constant, high levels of vacuum. Others, such as those who work in quiet environments, may have avoided other electrical pump systems due to the noise associated with these products.

Edison was initially developed by Orthocare under the Defense Advanced Projects Agency’s (DARPA) Revolutionizing Prosthetics program under contract with the Johns Hopkins Applied Physics Laboratory, and will be available for broad commercial release in the 4th quarter of 2011.