introduction

Phantom limb pain treatment

The German Aerospace Center (DLR) is researching on the treatment of phantom limb pain using Virtual Reality therapy. With funding from the Helmholtz Research Agency, NEEEU is collaborating on the design and development of a holistic therapy system based on Virtual Reality that aids the therapy goals in a playful and engaging way.

The challenge

Phantom limb pain is pain that seems to come from a part of the body that is no longer present. Many people with amputated limbs will experience some form of phantom limb pain. One of the most efficient ways to treat this issue is through visual stimulation, and in the past methods such as mirrors were used to reflect the image of the intact limb and simulate the presence of the missing limb. A team of researchers at the Institute of Robotics and Mechatronics of the German Aerospace Center (DLR) has gone one step further, pioneering a promising new technique - VVITA, which uses muscle sensors to predict the movement of lost limbs. Our challenge was to design and build a virtual reality environment that met the unique needs of both patients and therapists and would bring relief to patients by letting them control digital limbs and perform the exercises in a virtual space.

A journey of healing

We applied a human-centred process when designing the platform, adjusting and modifying the experience through empathetic lenses in collaboration with experts and patients. Given the chronic nature of phantom limb pain, the platform needed to be used by patients at regular intervals over a period of 6 weeks. From a design perspective, the user journey needed to span over the course of this whole treatment period. With this in mind, we introduced a sense of temporality and progression to the platform.

Virtual world and activities

Rehabilitation therapy can feel repetitive and tiring. In order to sustain patient motivation over several sessions, we created an immersive setting filled with engaging activities. As therapists underlined that making the virtual experience feel too much like real life might cause emotional distress in some people, we maintained a degree of abstraction in the visual design of the 3D assets in general, and of the virtual limb in particular.

Testing the prototypes at the clinic

During the development of the platform, we developed several iterations of the prototypes to test different questions. For example, how intuitive is the interface for therapists? Which rehab exercises could be turned into Virtual Reality actions? And can we provide feedback about the success to both the patients and the therapists?

An intuitive interface for therapists

By using the custom interface, the therapists can monitor the signals from the sensors and guide the patients while the patients are immersed in the Virtual reality world doing the different exercises. All the data needed is visualised: the sensors measuring the muscle and nerve activity, the image the patients are seeing and how well the rehab exercises are being executed. The therapist can also guide the patients, choosing which exercises to do next and the level of difficulty.

Impact

The redesigned experience is being used by DLR researchers to conduct a statistical study in collaboration with therapists from different international institutions. Preliminary results show that our redesigned platform already speeds up the training of therapists and reduces the time needed to get patients comfortable with the system. The process is being trialled across multiple hospitals in Northern Italy.