Skip to content
Open menu Close menu

Research Projects

The following gives a brief overview of some of the research projects undertaken by the medical engineering research team at Bradford


The role of venous abnormalities in neurological disease

Because there are no obvious moving parts, it is all too easy to ignore the biomechanics of the brain. Yet the intracranial space is a finely tuned dynamic mechanism, involving three fluids: blood, cerebrospinal fluid (CSF), and interstitial fluid, all of which interact with each other in a precise and orderly manner. Traditionally, the cerebral venous drainage system has been viewed simply as a series of collecting vessels channelling blood back to the heart. However, recent research is revealing that the cerebral venous drainage plays an important role in regulating the intracranial fluid system - a role that appears to influence both perfusion of the brain parenchyma and the dynamics of the CSF system.

Prof. Clive Beggs and Prof. Simon Shepherd are currently working with clinical teams at the University of Buffalo, USA, and the University of Ferrara, Italy, investigating the role of venous abnormalities in neurological disease. This work is revealing that blockages in the cerebral venous drainage system profoundly alter the dynamics of CSF flow; something that may play a role in the progression of diseases such as normal pressure hydrocephalus and multiple sclerosis.

Key publications:

  1. Beggs CB: Venous Haemodynamics in Neurological Disorders: An Analytical Review with Hydrodynamic Analysis. BMC Medicine. BMC Med 2013, 11:142.
  2. Zamboni P, Menegatti E, Conforti P, Shepherd S, Tessari M, Beggs C: Assessment of cerebral venous return by a novel plethysmography method. J Vasc Surg 2012, 56:677-685.
  3. Beggs C, Shepherd S, Zamboni P: Cerebral venous outflow resistance and interpretation of cervical plethysmography data with respect to the diagnosis of chronic cerebrospinal venous insufficiency. Phlebology 2012. [Epub ahead of print]
  4. Magnano C, Schirda C, Weinstock-Guttman B, Wack DS, Lindzen E, Hojnacki D, Bergsland N, Kennedy C, Belov P, Dwyer MG, Beggs CB, Zivadinov R: Cine cerebrospinal fluid imaging in multiple sclerosis. J Magn Reson Imaging 2012, 36:825-834.
  5. Beggs C, Shepherd S, Dwyer M, Polak P, Magnano C, Carl E, Poloni G, Weinstock-Guttman B, Zivadinov R: Sensitivity and specificity of SWI venography for detection of cerebral venous alterations in multiple sclerosis. Neurol Res 2012, 34:793-801

Hydrodynamic model of the intracranial space.

Legend: SSS = superior sagittal sinus; STS = straight sinus; SAS = sub-arachnoid space; CSF = cerebrospinal fluid; AV = arachnoid villi; CP = choroid plexus; FM = foramen magnum; WM = windkessel mechanism; SR = Staling resistor; VL = lateral ventricle; V3 = third ventricle; V4 = fourth ventricle; AoS = aqueduct of Sylvius; IJVs = internal jugular veins; VVs = vertebral veins.

Hydrodynamic model of the intracranial space (above), showing the interactions between the arterial and venous blood flows and the CSF. 


Cell-conducting implants for cartilage repair

Osteoarthritis is a leading cause of functional disability and loss of independence in older adults globally, causing significant economic impact (1-2% GDP), yet it is currently incurable. Total joint replacement is a very successful intervention, but it is a highly invasive procedure and implants have a limited lifetime. The development of treatments that can be used to repair the cartilage, rather than remove and replace it, has the potential to improve life for millions of people. These implants require mechanical properties that match the cartilage and underlying bone, they must exchange synovial fluid with the surrounding tissues and be so biocompatible that cells colonize them. Developing osteochondral implants that meet all these requirements is major challenge, requiring a broad range of skills from across the fields of engineering and biology.

Dr Peter Twigg is leading an international effort to develop osteochondral implants with functional gradients, such that they mimic cartilage, bone and, importantly, the transitional zone between them. The project brings together specialists in a number of areas and involves the University of Sheffield, University of Durham, Sichuan University and the Chinese Academy of Sciences, Beijing. This work is supported by the Global Priorities initiative, through the Medical Research Council in the UK and the Ministry of Science and Technology in China.

Understanding the nanostructure and nanomechanics of these implants, together with the way cells interact with them, is a significant part of this project.  Dr Colin Grant, a graduate of Medical Engineering at Bradford, is using advanced atomic force microscopy techniques to enable pre-clinical optimisation of the structure and properties of these biomaterials. He is interested in collagen based tissue mechanics at the nano-level, from individual collagen fibrils to bulk tissue. Active research projects include work on skin (scar tissue), arteries & veins (including umbilical cord) and ocular tissue (cornea, sclera & retina).

Cell-conducting implants for cartilage repair.

(Above left) – AFM phase image of a section of skin containing tattoo ink particles

(Above right) – Fracture mechanics on a 100nm diameter collagen fibril, AFM height image to show area of plastic deformation.

  1. C. Grant, P. Twigg, M. Savage, H. Woon and D. Greig, ‘Mechanical investigations on agar gels using atomic force microscopy: Effect of deuteration’, Macromolecular Materials & Engineering, 297 (2012) 214-218
  2. C. Grant, P. Twigg and D. Tobin, ‘Static and dynamic nano-mechanical properties of human skin tissue using atomic force microscopy: Effect of scarring in the upper dermis’, Acta Biomaterialia, 8 (2012) 4123-4129
  3. G Grant & P. Tiwgg, ‘Psuedo-staic and dynamic nano-mechanics of the tunica adventitia in elastic arteries using atomic force microscopy’, ACS Nano, 7 (2013) 156-464
  4. C. Grant, M. Phillips, N. Thomson, ‘Dynamic mechanical analysis of collagen fibrils at the nanoscale’, Journal of the Mechanical Behaviour of Biomedical Materials, 5 (2012) 165-170
  5. C. Grant, D. Brockwell, S. Radford, N. Thomson ‘Tuning the elastic modulus of hydrated collagen fibrils’, Biophysical Journal, 97 (2009), 2985-2992
  6. C. Grant, P. Twigg, A. Egan, A. Moody, A. Smith, D. Eagland, N. Crowther and S. Britland, ‘Poly(vinyl alcohol) hydrogel as a biocompatible visco-elastic mimetic for articular cartilage’, Biotechnology Progress, 22 (2006)1400-1406

Friction and Lubrication Behaviour of Newly Developed Zirconia Toughened Alumina Ceramic Femoral Heads Vs Carbon Fibre Reinforced Poly Ether Ether Ketone Acetabular Cups And Metal-On-Metal Hip Resurfacing Implants

Friction and lubrication behaviour of zirconia toughened alumina (ZTA) ceramic heads articulating against carbon fibre reinforced polyether-ether-ketone (CFR PEEK) cups with diameters in the range 38-60mm and radial clearances in the range 30-930μm have been developed, investigated and compared with those of metal-on-metal hip resurfacing implants with 38-60mm diameter having diametrical clearances of 100-314µm. 

Friction testing is carried out using pure bovine serum and aqueous solutions of bovine serum (BS), with and without carboxy methyl cellulose (CMC), adjusted to a range of viscosities (0.001-0.236 Pas) using a friction hip simulator. Stribeck analysis is carried out to establish the lubricating regime of these artificial joints which suggested mixed lubrication as the dominant mode. This study showed comparable friction factors between both type of joints with ZTA ceramic on CFR PEEK causing higher friction factors for only pure bovine serum and diluted 25vol%BS+75vol% distilled water having viscosities of 0.00157 Pas and 0.00143 Pas, respectively.


Effect of Cannabinoids in Acceleration of Wound Healing of Chondrocyte (cartilage) and Osteoblast (bone) cell mono- and multi-layers

Cannabinoids have been shown to have analgesic, anti-spasmodic, anti-convulsant, anti-tremor, anti-psychotic, anti-inflammatory, anti-oxidant, anti-emetic and appetite-stimulant properties. Certain cannabinoid extracts have been reported to have anti-inflammatory effects and reduce cartilage damage in arthritic joints. A commercial synthetic cannabinoid was, therefore, used in this work to investigate its effect on cartilage and bone protection and repair using scratch assay wound models.  These results confirmed that cannabinoid supplemented and wounded mono- and multi-layers showed complete wound closure after ~ 26 hours suggesting that cannabinoid had positive effect on chondrocyte and osteoblast cell proliferation and migration.

Keynote invited papers (and lectures)

[1] H. Everitt1, M. Elliott1, R. Bigsby1, I. Khan1, E. Pegg1 and M. Youseffi2, 2011,

1 Biomet UK Healthcare Ltd., Waterton Industrial Estate, Bridgend, South Wales, CF31 3XA

2 University of Bradford-Medical Engineering Department, Bradford BD7 1DP

COMPARISON BETWEEN FRICTION AND LUBRICATION BEHAVIOUR OF LARGE DIAMETER ZTA CERAMIC VS CFR PEEK AND MOM HIP RESURFACING IMPLANTS [Corresponding Author: Email: m.youseffi@bradford.ac.uk]

IMechE (Medical Division) Invited Speaker:  Engineers and Surgeons: Joined at the hip III – 1-3 November 2011.

[2] M. Youseffi1*,  S.A. Javid1,  A. Kamali2,  J.T. Daniel2,  J. Daniel3, and D. J.W. McMinn 3, 2010,

THE Effect of Clearance UPon Friction AND LUBRICATION of large diameter Hip Resurfacing PROSTHESES Using Blood  and Serum-BASED lubricants [Corresponding Author: Email: m.youseffi@bradford.ac.uk]

Cardiff university, 15 january 2010, new orthopaedic implants: properties and surgical development, 2010.  

[3] M. Youseffi*1, S.A. Khaghani1, M.C.T. Denyer2,3, and F.A. Javid4, 2010,

Effect of Cannabinoids in Acceleration of Wound Healing of Chondrocyte Monolayer

LEEDS UNIVERSITY, 7 January 2010, SCHOOL OF MECHANICAL ENGINEERING- Institute of Medical and Biological Engineering: Cartilage Tissue Engineering and Orthopaedic Workshop [*Corresponding Author: Email: m.youseffi@bradford.ac.uk]

[4] S. Afshinjavid and M. Youseffi, (2010), Effect of cup deflection on friction of hip resurfacing prostheses with various clearances using blood and clotted blood as lubricants, The World Congress on Engineering, WCE 2010, London, U.K., Volume I, ISBN: 978-988-17012-9-9 and ISNN: 2078-0958, full paper, pages 598-600.

[5] S. Afshinjavid and M. Youseffi, 2009, The effect of clearance upon friction of large diameter hip resurfacing prostheses using blood, clotted blood and bovine serum as lubricants, O. Dössel and W.C. Schlegel (Eds.): WC 2009, International Federation for Medical and Biomedical Engineering (IFMBE) Proceedings 25/IX, pp. 418–420, Sept 7-12 2009.

[6] M. Genedy, M. Youseffi, A. Abdeldayem and M.C.T. Denyer, 2013,

The Effect of HU308/TGF-β3 combination on MG-63 osteoblast wound healing, proliferation and migration

The 23rd Annual International Cannabinoid Research Society Symposium on the Cannabinoids June 21 - 26, 2013 UBC Campus Vancouver, BC Canada.

[7]M. Genedy, M. Youseffi, A. Abdeldayem and M.C.T. Denyer, 2013,

The Effect of Monoglycerol lipase inhibitor (URB602) on the acceleration of MG-63 osteoblast wounded monolayers

The 23rd Annual International Cannabinoid Research Society Symposium on the Cannabinoids June 21 - 26, 2013 UBC Campus Vancouver, BC Canada.

[8] M. Genedy, Nina Hönig, A. Abdeldayem, M.C.T. Denyer  and M. Youseffi, 2013,

THE EFFECT OF CANNABINOID ON HEALING of scrAtched HaCaT cell monolayers

The 23rd Annual International Cannabinoid Research Society Symposium on the Cannabinoids June 21 - 26, 2013 UBC Campus Vancouver, BC Canada.

[9]A. Abdeldayem, M. Youseffi, M. Genedy and M.C.T. Denyer, 2013,

The Effect of Different Concentrations of synthetic Cannabinoid receptor 2 agonist (HU-308) on Healing of scratched Chondrocyte Monolayers

The 23rd Annual International Cannabinoid Research Society Symposium on the Cannabinoids June 21 - 26, 2013 UBC Campus Vancouver, BC Canada.

[10] A. Abdeldayem, M. Youseffi, M. Genedy and M.C.T. Denyer, 2013, 

The Effect of Different Concentrations of URB602 on Healing of scratched Chondrocyte Monolayers

The 23rd Annual International Cannabinoid Research Society Symposium on the Cannabinoids June 21 - 26, 2013 UBC Campus Vancouver, BC Canada.

[11] M. Genedy, M. Youseffi, A. Abdeldayem and M.C.T. Denyer, 2013,

The Effect of Synthetic Cannabinoid HU308 on Fibronectin and Collagen Type I Expressions in MG-63 Osteoblast Cells

7th UK and RI Postgraduate Conference in Biomedical Engineering and Medical Physics

Guildford, Surrey, UK, 9th-11th July 2013.

[12] M. Genedy, M. Ahmed, F. Sefat, M.C.T. Denyer and M. Youseffi, 2013,

The effect of TGF-β3, HCl, HCl/BSA and pH on wound healing of cultured osteoblast monolayers

7th UK and RI Postgraduate Conference in Biomedical Engineering and Medical Physics

Guildford, Surrey, UK, 9th-11th July 2013.

[13] A. Abdeldayem,  M. Youseffi, M. Genedyand M.C.T. Denyer, 2013,

The synthetic cannabinoid WIN55, 212-2 encourages chondrocytes dedifferentiation

7th UK and RI Postgraduate Conference in Biomedical Engineering and Medical Physics Guildford, Surrey, UK, 9th-11th July 2013.


Biomechanical adaptations and compensatory mechanisms used for locomotion in individuals with lower-limb amputation 

Prosthetic feet are typically fixed to the prosthetic shin pylon via a rigid attachment or a rubber-snubber (flexible attachment). A recent advance in hydraulic technology has led to the development and use of robust/reliable hydraulic prosthetic ankles. Whilst such devices are proving to be popular with amputees, little is known about how such ankles alter foot function, and subsequently the biomechanics of gait.

Dr Buckley, working in collaboration with Chas A Blatchford & Sons Ltd (UK’s leading prosthetics manufacturer) and clinical staff at the Rehabilitation Medicine Centres in Manchester and Sheffield, is currently investigating how the functioning of a carbon-fibre foot is altered when attached to the prosthetic shin pylon via a hydraulic rather than fixed ankle.

Question being addressed include: 

  • How does the loading and moment-of-force pattern change when using a hydraulic ankle?
  • Does the location of the modal deflection point (representative ankle joint centre) change when using a hydraulic ankle?
  • Do gait dynamics (adaptability) improved using a hydraulic ankle?
  • What hydraulic resistance is required to optimise gait biomechanics when negotiating slopes and stairs?

Scientific Journal Articles

  1. De Asha AR, Munjal R, Kulkarni J, and Buckley JG. (2014) Impact on the biomechanics of overground gait of using an 'Echelon' hydraulic ankle-foot device in unilateral trans-tibial and trans-femoral amputees. Clin Biomech; 29: 728-34.
  2. De Asha AR and Buckley JG. (2014) The effects of walking speed on minimum toe clearance and on the temporal relationship between mini mum clearance and peak swing-foot velocity in unilateral trans-tibial amputees. Prosth Orthot Int; EPub, doi: 10.1177/0309364613515493.
  3. Johnson L, De Asha AR, Munjal R, Kulkarni J, and Buckley JG. (2014) Toe clearance in unilateral transtibial amputee gait: effects of passive hydraulic ankle. J Rehabil Res Devel; 51(3): 429-438.
  4. De Asha AR, Munjal R, Kulkarni J, and Buckley JG. (2013) Walking speed related joint kinetic alterations in trans-tibial amputees: impact of hydraulic ‘ankle’ damping. J Neuroeng Rehabil; 10(1):107
  5. Buckley JG, De Asha AR, Johnson L, and Beggs C. (2013) Understanding adaptive gait in lower-limb amputees: insights from multivariate analyses. J Neuroeng Rehabil; 10(1):98.
  6. De Asha AR, Johnson L, Munjal R, Kulkarni J, and Buckley JG. (2013) Attenuation of centre-of-pressure trajectory fluctuations under the prosthetic foot when using an articulating hydraulic ankle attachment compared to fixed attachment. Clin Biomech; 28: 213-24.

Conference Presentations

  1. De Asha A, Johnson L, Kulkarni J, Munjal R and Buckley JG (2013) Minimum toe clearance during unilateral trans-tibial amputee gait; effects of using a hydraulically controlled ankle-foot device. Proceedings of Annual Scientific Meeting of International Society for Prosthetics & Orthotics, Blackpool 4-5th Oct.
  2. Evangelopoulou E, Foster R, Twiste M, and Buckley JG (2013) Importance of lead limb ankle motion in achieving foot clearance during obstacle crossing. Proceedings of Annual Scientific Meeting of International Society for Prosthetics & Orthotics, Blackpool 4-5th Oct.
  3. De Asha A and Buckley JG (2013) A simple to implement and robust method of identifying ‘minimum toe clearance’ events during unilateral trans-tibial gait. Capability After Limb Loss Conference of IPEM, Birmingham 26th Sept.
  4. De Asha AR, Johnson L, Munjal R, Kulkarni J, and Buckley JG (2012) Prosthetic-limb ankle kinetics and energy storage/return when using a hydraulic ankle device in unilateral trans-tibial amputees. Proceedings of 1st Joint World Conference of ISPGR and Gait & Mental Function, Trondheim, 24-28th June; p510-11.
  5. De Asha AR, Johnson L, Bose R, Bavikatte G, McKendrick A, Kulkarni J, and Buckley JG (2011) Effects of a hydraulic ankle on gait function and symmetry in unilateral lower limb amputees. ISPO Annual Scientific meeting, London Oct 7-8.
  6. Brown, SJ, De Asha AR, Johnson L, Kulkarni J, Munjal R, and Buckley JG (2011). Roll-over characteristics & ankle joint kinetics using low-profile dynamic response foot with fixed versus hydraulic ankle in trans-tibial amputees. ISPO Annual Scientific meeting, London Oct 7-8.
  7. Rhea CK, De Asha AR, Johnson L, and Buckley JG. (2011) Gait dynamics in trans-tibial amputees when using different prosthetic ankles. Progress in Motor Control VIII, Cincinnati, OH, July 21st-23rd.

Invited Talks

  1. De Asha A. "Modelling issues in lower-limb amputee research; interpreting joint kinetics." To faculty and research students at Queens University, Kingston, Ontario, April, 2014.
  2. De Asha A. "Gait function in lower-limb amputees: The University of Bradford’s Medical Engineering Research Group." To C-Motion User Group, Manchester Met University, Manchester, March, 2015.