In: Anatomy and Physiology
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
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.