Question

Hip implants have experienced significant design and material changes since their introduction. These changes have led to more successful biomaterials in orthopaedic implants.

Discuss the improvements in orthopaedic implant materials and discuss the mechanical performances why the current materials are more successful than predecessors

Answer 1

Bones and joints of body are prone to degenerative changes which may be a result of growing age or injury or other pathologies.
This has led to various surgical procedures being carried out on bobes and joints. The joint replacement or bone grafting have become a very common procedure in modern times. Implants made out of biomaterial are being used extensively.
With advances in medicine and surgery, the biomaterial used for implants has also evolved from using an inert biomaterial for implants to use of biodegradable materials. The implants which are being used now a days consists of materials tha elicit specific responses at molecular levels.
1. First generation biomaterial: these bbiomaterials were inert and had minimal toxic reaction with the host.
They consists of metallic material such as stainless steel, cobalt and chromium alloy and titanium. These materials do not corrode, are inert and provides maximum strength and are used in plates, screws and nails.

The non metallic biomaterials or ceramic biomaterial includes alumina, zirconia and several porous ceramics. They are resistant to corrosion, have high strength and biocompatible. They are used for femoral head and acetabulum.
2. Second generation: Polymers such as silicone rubber, PE, acrylic resins, polyurethanes, polypropylene (PP) and polymethylmethacrylate are also used as implants. They are used to anchor bone to the prosthesis. They are biodegradable materials. These are used in sutures, plates, rods, screws and pins. They are widely use to fix femoral head and neck, acetabular repairs.
3. Third generation: Third generation implants consist of biomaterial made of natural and synthetic polymers that elicit tissue response that helps attachment and proliferation at the site. These materials should be minimally toxic, biodegradable and promote bone regeneration. They are used in cartilage and ligament reconstruction surgeries.