Wednesday, September 21, 2011

Robots Assist in Physical Therapy

The newsletter “NIH Catalyst” reports that the NIH Clinical Center is using robots to provide physical therapy assessment and training to help patients whose muscles have been weakened by cerebral palsy, TBI, and/or other neurological disorders. The robots are able to operate remotely and help patients in their home.

A staff scientist at the NIH Center, Hyung-Soon Park in the Functional and Applied Biomechanics Section (FABS), is leading the design and development of the robots to develop a telerehabilitation system that can remotely assess a patient’s condition.

Park’s laboratory has developed two robotic mechanisms that work together to rehabilitate the elbow joint. The first mechanism resembling a human arm is a “Haptic Mannequin Device” (HMD) that relies on the sense of touch and is attached to a computer in the clinician’s office.

The second is a mechanical arm brace called a “Wearable Stretching Device” (WSD). The patient wears the WSD at home or in some other location but must be near a computer that is connected to the internet to communicate.

Normally a clinician has to have physical contact with a patient who suffers from involuntary muscle spasms caused by neurological impairments to feel the muscles, diagnose problems, and provide physical therapy.

However, with the HMD-WSD setup, the clinician moves the HMD mechanical arm and then a signal travels via the internet to the patient. At this point, the WSD arm brace mimics the movement and stretches the muscles. The WSD records muscle resistance and relays the information back to the HMD so it moves and feels just like the patient’s arm. The two devices talk to each other, sharing information instantaneously as if the patient and the clinician are in the same room.

Clinical trials with the HMD-WSD system are expected to begin in the near future. After the system has been perfected, Park hopes to develop devices that focus on the knee, ankle, wrist, and shoulder.

The robotic arm can also be used as a tool to standardize medical assessments and to train clinicians who want to improve their physical therapy skills. It can be programmed using patient data and can provide realistic consistent movements including imitating spasticity and contracture affecting muscles.

The researchers are also working on a robotic leg to help to eliminate crouch gait in children that can lead to making walking difficult and exhausting for children with cerebral palsy. The robot device works to help strengthen the leg and also helps children stand more upright.

The researchers have also developed a self-paced treadmill that is helping patients who have suffered from TBI relearn how to walk. The machine enables patients to choose their speed via sensors that are attached to the body and linked to a computer program developed by FABS. The treadmill faces a large screen where a virtual world is projected so that patients are able to walk through the mock terrain and learn to navigate in difficult situations.