Objectives
- Identification and development of a number of suitable bonding agents/fracture fixation materials and methods for joining hard tissue
- Optimised bonding procedures with potential for application in clinical bone fracture fixations
- Initial biocompatibility, mechanical stability, safety and efficacy data to support ethical approvals for clinical trials and submission to regulatory bodies
Project Outline
Half of an orthopaedic surgeon’s time is spent managing fractures. A number of treatments are available, eg external casts and internal fixation with wire, screws, plates and nails. Stabilising fractures is important for the wellbeing of the patient. Fixation of facial fractures and osteotomy of the jaw bone for correction of underlying deformities are one of the most common daily procedures in all maxillofacial units in the UK. These cases require bone fixation using plates and screws. Further operations may be needed for removal of plates, screws and nails. The proposed study aims to explore the feasibility of developing new bonding agents and fixation materials/ techniques for joining a variety of different short and long bones. In spite of considerable research in developing tissue bonding agents, there are no clinically acceptable and commercially available bone bonding materials and rapid fixation methods for everyday clinical applications.
The proposed work will investigate the feasibility of modifying or developing new bone bonding/sealing agents (biomaterials and bioactive agents) and associated materials (eg adhesion promoters), as well as novel bonding methods (eg surface preparation of bone, dispensing and curing of bonding/sealing agent, etc) for fixation and repair of fractured short and long bones. Medical grade adhesives such as cyanoacrylates for soft tissue bonding, incorporating reinforcing functionalities for bone applications will be evaluated as will the modification of commercially available bone cements with the incorporation of additional bonding agents to provide adhesive characteristics. A range of biodegradable polymers will also be used as a base resin for producing adhesives by incorporation of additives such as tacifiers, cross-linking agents and photo initiators. One of the challenges will be to maintain alignment of bone fragments using clinically acceptable bonding agents to replace screws, wires and nails. Several potential bonding agents will be developed and tested for their ability to join bones together and to initiate and accelerate bone growth and repair.
Two prominent researchers; Professor Pankaj Vadgama of QMUL and Professor Simon Donell (Orthopaedic Surgeon, Norwich University Hospital & University of East Anglia, NNUH/UEA) will be the joint academic and clinical partners for this project. They will support biomaterial developments, pre-clinical trials and biocompatibility testing. Professor Mehdi Tavakoli from TWI will lead this project and provide established knowledge and expertise in designing the relevant polymer formulation, developing novel dispensing, and curing methods of novel bonding agents, surface modification/ adhesion promotion of the bones and associated joining procedures.
Relevant Industry Sectors
Technical and Economic Benefits
This is an area of major unmet clinical need and if successful, could lead to development of a new generation of bonding agents/materials and associated devices which are expected to be of significant interest to many healthcare companies, clinicians and healthcare providers.
The orthopedic small bone and joint device market is estimated to be about 1.8 billion with an 8.9% growth. Small bone and joint problems account for 51% of office visits to orthopedic surgeons and 24% of surgical procedures. For example in 2008, the combined US market for small joint, small bone and extremity devices was valued at $673.8 million (www.scribd.com/doc/57155894/U-S-Market-for-Small-Bone-Joint-Orthopedic-Devices-2009). Small bone and joint applications has been one of the fastest growing areas in orthopedics. This sector of the market has outpaced the more established areas. There are also considerable interests in bone fracture fixation in maxillofacial applications and cosmetic surgery. Fixation of small bones (ie, distal radial fractures) is complicated by the difficulty in using screws and pins, and complication rates due to intra-articular misalignment and non-unions is as high as 62% (Weber 1986). An ideal bonding agent for bone repair should promote rather than retard osteoblastic activity (Drobnic 2006), and should resorb in the timeframe of naturally healing bone. The long-term goal of the proposed work is to create a resorbable bonding agent or fixation device and clinically acceptable bonding procedures which can be used effectively to join bone fragments during fracture fixations.
The clinical application of bone bonding agents and rapid bonding procedures would completely change the environment of the NHS and global treatments of bone fractures. Most fractures would be treated during a short-stay in hospital (less than 24 hour) using new image intensification to guide the placement and curing of the bonding agent and day theatre facilities freeing up in-patient beds. Hospital in-patient stays for fractures would dramatically be reduced. As well as direct health care benefits, societal benefits would also be significant. Returned to self-care, with reduction of need for social and community healthcare services, significant earlier return-to-work times, and faster return to social and leisure activities would be other expected potential advantages of the new procedures.
It is hoped this project will lead to generation of novel biomaterials and joining procedures leading to new patents and new IPs which could then be exploited by TWI in collaboration with selective industrial and clinical partners.