A new method combining a variety of technologies aims to address treatment of phantom limb pain (PLP) following amputation. According to a news release from the University of Gothenburg, The Sahlgrenska Academy, Chalmers researcher Max Ortiz Catalan developed the method.

Catalan tested the method using a case study that encompassed a patient who sustained phantom pain varying from moderate to unbearable since the loss of his arm, 48 years ago. Following the period of treatment with the method, the patient’s pain was reportedly drastically reduced. Currently, the release says, the patient has periods where he is entirely free of pain and no longer awakened by intense periods of pain during the night.

See it in action here

The method is engineered to use muscle signals from the patient’s arm stump to facilitate augmented reality. Electrodes on the skin pick up electrical signals in the muscles. These signals are then translated into arm movements by complex algorithms. The release states that the patients are able to see themselves on a screen with a superimposed virtual arm controlled using their own neural command in real time.

What sets the method apart from previous treatments, Catalan says, is that, “the control signals are retrieved from the arm stump, and thus the affected arm is in charge. The promotion of motor execution and the vivid sensation of completion provided by augmented reality may be the reason for patient improvement,” Catalan adds.

A variety of the system’s features may be key players in the relief of pain, Catalan says, ‘The motor areas in the brain needed for movement of the amputated arm are reactivated, and the patient obtains visual feedback that tricks the brain into believing there is an arm executing such motor commands.”

The release states that a clinical study is scheduled to be conducted to assess the technology. The technology has been developed in collaboration with Chalmers University of Technology, Sahlgrenska University Hospital, the University of Gothenburg, and Integrum. The study is intended to target patients who have phantom pain and who have not responded to other currently available treatments. A total of three Swedish hospitals and other European clinics will cooperate during the study, researchers say.

The release also reports that the research group has developed a system for home-based use. Upon approval, the patient will have the ability to apply therapy independently at home. The team adds that other patient groups requiring rehabilitation of mobility, including stroke victims and some patients with spinal cord injuries, may also be able to use the treatment.

[Source: University of Gothenburg, The Sahlgrenska Academy]