Experience with Swedish multifunctional prosthetic hands controlled by pattern recognition of multiple myoelectric signals

Clinical experience with two types of multifunctional prosthetic hand, controlled by pattern recognition of multiple myoelectric signals is reported. The prostheses have been used for between one and five years by five patients. The pattern recognition control system enabled the patients to control six separate movements accurately after a short period of training. One of the tested prostheses, the SVEN-hand, was not reliable enough to allow clinical use outside the laboratory. The ES-hand, a second generation multifunctional prosthesis, has promising features, being self-contained and fast moving. It is concluded that multi-functional prosthetic hands help amputees to avoid tiresome and awkward compensatory movements. Their scope, however, does not extend beyond that of conventional myoelectric prostheses. Their combined movements are cosmetically more appealing than a single three-point grip. In order to gain wider acceptance, multifunctional prosthetic hands must reach a state of development comparable to conventional myoelectric devices particularly with regard to weight and compactness. A pattern recognition control system is essential to the design.