Competition Heats Up in Foot Drop Stimulator Market

by James Cavuoto, editor

The market for foot-drop stimulation systems is poised for increased competition with the entry of several new devices. The product category represents one of the more mature segments of the market for neural prostheses based on functional electrical stimulation. Foot drop is a form of lower limb paralysis that often accompanies stroke, leaving the patient with gait abnormalities resulting from the lack of ankle dorsiflexion.

Earlier this month, Innovative Neurotronics Inc., the Bethesda, MD subsidiary of Hanger Orthopedic Group, announced that it launched the WalkAide system, its first offering in a line of FES devices. Founded January 2004, Innovative Neurotronics initially focused on clinical studies and protocol designs for the treatment of foot drop. This effort culminated with the WalkAide System, which includes diagnosis, treatment modalities, and delivery of an electrical stimulation device by a trained medical practitioner.

Cleared for marketing by the U.S. Food and Drug Administration in September 2005, the WalkAide System allows a qualified clinician to analyze the patient’s leg and foot movements, which are identified by a patented sensor technology called an accelerometer and transmitted via a Bluetooth connection. Once the device is fit on the patient, electrical signals are sent to the peroneal nerve, prompting the muscles to raise the foot at the appropriate time and allow the patient to walk more normally. Worn around the leg, just below the knee, the wireless AA battery-operated device is about the size of a deck of cards. It is priced at $4495. WalkAide was originally developed during the 1990s by Richard Stein at the University of Alberta.

In addition to improving the patient’s gait, medical benefits of the WalkAide System are increased mobility, strength, and endurance; decreased energy expenditure; prevention, retardation, and/or reversal of muscle atrophy; and maintained or increased joint range of motion. Further benefits may include reduced incidence of injury, increased circulation, muscle re-education, maintained or increased bone density, and strengthened damaged central nervous system pathways and muscle/spinal circuits.

Innovative Neurotronics will not have the foot-drop market to itself. Industry insiders expect that Bioness Inc., the Valencia, CA firm founded by Alfred Mann, will soon gain approval of its FES device for treating foot drop, which is also based on surface stimulation.

Otto Bock’s Neurodan unit in Denmark is also developing an implanted foot drop system called ActiGait. The stimulating electrode is located under the skin just above the knee while the stimulator is located under the skin on the thigh. The surgical procedure is short, and can be carried out under local anesthesia.

The stimulation is activated by a wireless heel switch located in the shoe, which significantly eases the use of ActiGait, compared to other foot drop stimulators. The company expects to be in the European market this year and in North America sometime later.

FineTech Medical in Hertfordshire, U.K. was the first company to enter the market for foot drop stimulators. Its implantable StimuStep system, developed at the University of Twente, received CE mark clearance in 2004.