View Full Version : *** Exciting PhD studentship opportunity at Imperial College London ***

02-14-2011, 11:43 AM
PhD studentship: Ensuring new ceramic hip designs do not fail by an anticipated mechanism

Squeaking has been reported as the most common complication relating to ceramic on ceramic hip replacement. Edge loading of the ceramic bearing during deep flexion activities, e.g. rising from a low chair or tying a shoelace, have been identified as mechanisms that, through damaging the bearing surface and increasing friction, can lead to squeaking. Although squeaking is usually intermittent and tolerated by patients, the damaged bearing surface and potentially elevated friction must be considered when ceramic devices are being developed. This is particularly important now because several manufacturers are developing ceramic on ceramic hip resurfacing devices. The larger diameter, thinner wall thickness and potentially reduced range of motion of hip resurfacing indicate the devices are not equivalent to conventional total hip replacement, and the consequences of edge loading, i.e. damaged bearing surface and increased friction, may be more serious than intermittent squeaking.

Although much is known about the loading of the hip during routine activities, there is little knowledge of the posterior loads applied during deep flexion activities when anterior impingement forces the head to ride over the rim of the acetabular cup (i.e. the loading that causes the damage mentioned above). The primary aim of this PhD is to determine these loads such that appropriate tests can be designed to mitigate the risks of edge loading. Computational modelling will be performed using ADAMS/LifeModeler simulation software, with kinematic inputs taken from cohorts of healthy subjects and pre and post op hip resurfacing patients using a combination of optical motion analysis and wireless electromyography. A secondary aim of the PhD is to identify muscle groups that, if strengthened, could potentially reduce the probability of edge loading.

Research in the field of medical engineering at Imperial involves collaborating with multiple departments (Bioengineering, Mechanical Engineering and Surgery & Cancer), and the applicant must be happy to work in an interdisciplinary team that covers different sites. Funding for this project comes from EPSRC money, therefore the studentship covers fees and bursary for UK residents but only covers fees for EU students. Applicants should have (or expect to achieve) at least a 2.1 degree in engineering, any of the physical sciences, mathematics, biological sciences, physiology or medicine.

For further information or informal discussion, please contact Jonathan Jeffers (details below). To apply for this PhD position, email a CV with cover letter to Jonathan Jeffers. Closing date 6th March although applications may be considered after this date in unusual circumstances.

Dr Jonathan Jeffers CEng FIMechE

Department of Mechanical Engineering (Room 635)
Imperial College
South Kensington
Tel: +44 (0)20 7594 5471
Fax: +44 (0)20 7594 5702