Tariq Rahman, Ph.D.

Research Interests

The Pediatric Engineering Research Lab (PERL) is involved in research of devices and therapies that will assist and rehabilitate children with neuromuscular disabilities and orthopedic disorders, including muscular dystrophy, spinal muscular atrophy, arthrogryposis, spinal cord injury, and leg length discrepancies.

Current Projects

Force Controlled Limb Lengthening

Some children develop with one leg or one arm shorter than the other. To correct this problem, orthopedic surgeons often perform a procedure called Distraction Osteogenesis to lengthen the bone in the shorter limb. This procedure requires that a mechanical device (a distractor) be attached to the bone and either manually or automatically lengthened a fixed distance - usually about ½ mm/day. It is not clear if lengthening at a fixed rate is the best approach.

We are investigating the use of an automatic device that detects the force being applied to the limb during lengthening. We think that adjusting the rate at which a limb is lengthened to match the forces in the limb will lead to better results with fewer problems and less discomfort for the patient than current practice. In particular, this project concerns the development of a sensor and controller that will allow the distraction rate to be varied based on measuring the force developed during distraction. This is in contrast to the fixed-displacement-driven distraction approach used currently

Functional Orthosis for Children with Muscular Dystrophy

Children with neuromuscular weakness have difficulty in moving their arms and performing activities of daily living. This project addresses these concerns with the development of WREX - an orthosis that helps the arm move in space. The person's arm is placed in WREX, which then allows them to navigate their arm in space with their residual strength. WREX is primarily intended for people with muscular dystrophy and spinal muscular atrophy. People with these conditions lose the ability to place their arm in space due to weakness. The distal muscles are less affected and sensation remains intact. WREX has been patented and is currently available for purchase through JAECO Orthopedics. Research is continuing to power WREX with electric motors for kids with profound weakness, and adults with stroke.

Scoliosis Brace Compliance Sensor

Spinal bracing has been the mainstay of conservative treatment of idiopathic scoliosis. It has been shown to be effective in halting the natural history of progression of moderate idiopathic curves in most skeletally immature patients. The efficacy of the spinal orthoses is, however, dependent upon excellent patient compliance with a prescribed brace-wearing schedule.

Several studies on the effectiveness of these spinal orthoses have failed to address the issue of brace-wear compliance. Poor patient compliance with the prescribed brace-wear schedule has been well documented to be a major factor in brace failure and curve progression. Most studies were done retrospectively either by reviewing medical records or by telephone interviews of patients and parents. They relied on the patients reporting their average daily brace-wear time to determine their compliance.

The purpose of this study is to prospectively and accurately document the brace wear compliance of patients with idiopathic scoliosis being treated with the Wilmington brace by installing a monitor in the braces. The monitor records their actual brace-wear time and pattern of brace-wear, thus allowing the accurate assessment of brace-wear compliance without relying on the patient's subjective reports.

Sixty-one subjects with juvenile or adolescent idiopathic scoliosis who were braced with the Wilmington jacket were monitored with the compliance sensor. Patients were followed throughout their brace-wearing period. The data were downloaded at every clinical visit and then analyzed. Brace compliance was measured and compared with factors such as age and progression of scoliosis.

The compliance sensor was very effective and reliable in providing an objective measure of compliance. Results further demonstrated that compliance decreased as the child grew older; compliance is routinely overestimated by the patient. The study also shows that compliance was significantly less in patients whose scoliosis got worse compared with those whose did not get worse.

Research Group

  • Jin Yong Wee, M.S. - Graduate Student (M.S., Drexel University). Modeling the autodistraction procedure in limb lengthening. Using a motor to perform limb lengthening and controlled by a force sensor that measures stiffness in the distraction environment.

Selected Publications

Head, Pediatric Engineering Research Laboratory, and Senior Research Engineer, A.I. duPont Hospital for Children

Phone: (302) 651-6831

Fax: (302) 651-6895

Email: trahman@nemours.org

Office: A.I. duPont Hospital for Children

Department of Biomedical Research
A.I. duPont Hospital for Children
1600 Rockland Road
Wilmington, DE 19899


  • B.Sc. - University of Central Lancashire (United Kingdom)
  • M.S., Ph.D. - Drexel University