Medical and healthcare
Gait Trainer — portable gait monitoring system for rehabilitation
London Knee Clinic, Bath Institute of Medical Engineering, European Technology for Business
Monitoring gait - the way that someone walks - is the best way to assess progress after joint surgery or to help elderly people avoid injuring themselves in falls, but the equipment needed to do it tends to be large, expensive and confined to specialist gait laboratories.
Therefore, most patients don’t have the benefit of full gait analysis and clinicians have to rely on relatively crude methods involving visual inspection and simply asking the patient how they are getting on.
A European Commission Sixth Framework project was the springboard to develop a portable gait-monitoring system that could be taken to a patient to analyse gait in their own surroundings.
The London Knee Clinic and Bath Institute of Medical Engineering joined forces with ETB, which specialises in movement technologies and the algorithms to process them, to develop the Gait Trainer.
The system consists of a laptop computer connected to four sensor modules, which incorporate gyroscopes, accelerometers, software and an SD card to store data.
The algorithms developed by ETB use the sensors to calculate stride duration, the difference between the movement of left and right legs, and the movement of the knee, calf and thigh. It can be used in a surgery, clinic or the patient’s home, and can give information on walking for short or long distances, on flat surfaces, rough terrain or up and down stairs. It provides objective data that can be compared easily.
Development of orthopaedic stem cell concentrator
University of Southampton Medical School, Southampton University Hospitals NHS Trust (Southampton General Hospital, Department of Trauma and Orthopaedics), Smith & Nephew
The stem cells found within bone marrow have great potential for tissue engineering, as they can transform into bone or cartilage; orthopaedic specialists believe they could regenerate fractures and other skeletal defects that are otherwise reluctant to heal.
However, the clinical results from tests of these techniques have been variable, because it is difficult to obtain samples containing a high enough concentration of stem cells; the fluid collected from bone marrow tends to be diluted with blood and the methods used to concentrate the vital cells rely on expensive centrifuges that cannot be used under sterile conditions.
The three partners in this project had worked together before and came together to develop a stem-cell enrichment method that overcame the disadvantages of the existing equipment.
Smith & Nephew’s research team developed a device that uses acoustic waves to force the bone-marrow sample through a series of filters to concentrate the stem-cell fraction of the sample.
The clinical partners then tested the device using bone marrow donated by patients undergoing hip-replacement surgery; this also ensured the technology was developed according to the requirements of the surgical teams in harvesting and processing the bone-marrow samples at the optimum time, and incorporating this process into their routine.
The enrichment device is a single-use, standalone filtration unit that prepares skeletal stem cells for immediate use.
The team believes it will be useful for: long-bone fractures, which have a 10 per cent chance of not healing properly; spinal fusions in the elderly, of which one in five do not heal; and cartilage focal defect, which can occur after relatively minor fractures but can cause extreme pain and the locking of joints.
Temporal pixel multiplexing (TPM): a new method for producing medical images
University of Oxford; University of Nottingham
TPM is an imaging technique that embeds high-speed moving images into high-resolution still pictures.
The method was developed by Oxford University researcher Gil Bub as a way to correlate very fast functional events with high-resolution anatomical images using a single camera; this would normally require a complicated system with multiple cameras and complex optics and would run into problems with handling the bandwidth issues.
Bub devised it as part of a project involving high-speed imaging of cardiac cells.
The advantages of this system led Bub to collaborate with chip designers and Nottingham University to develop an on-chip TPM camera using conventional CMOS manufacturing techniques.
The system works by offsetting the exposure of pixels during the time the camera takes to produce a still image, so that the movie data is embedded in the parts of the still image that would normally be blurred.
The prototype at Oxford is embedded into an optical bench, but the Nottingham team’s research would allow TPM to be a function of portable cameras.
Potential for use in other scientific sectors is promising, the researchers say. Scientific imaging is a market currently worth more than $100m per year.