ABSTRACT
Many different recent research works that involve nanobiosensor detectors and are based on carbon nanotubes technology are introduced. This technology allows rapid screening of bone quality, could identify individuals that may be at increased risk of injury for certain occupations, and could detect cancer and neurodegenerative skeletal disorders. A group of researchers developed the Indentation-type Atomic Force Microscopy for early detection and for micro-and nanomechanical analysis of aging articular cartilage and osteoarthritis. Their ultimate goal was to develop an arthroscopic atomic force microscopy, which can be directly introduced into a knee or hip joint for early diagnosis and detection of articular joint diseases.28-30 The Magnetic resonance spectroscopy is also a new technology tool that could evaluate bone development, intervertebral disc degeneration, and even different spinal cord diseases. The functional magnetic resonance (f-MRI) and positron emission tomography (PET) are also useful tools for detecting tumours, and those tumours that generally have a high metabolic activity. 5.3 Nano Biologically Active materials and
Patients with early or advanced OA are usually afflicted with severe functional impairment and continuously seek different types of medications. The main purpose for treatment of OA is the relief of the patient from the unpleasant and disabling symptoms. As far as the conservative treatment of early OA is concerned, different types of drugs such as analgesics and anti-inflammatory, and symptoms and structure modifying drugs such as glucosamine C. sulfate,31chondroitin sulphate, hyaluronic acid and diacerein are mainly used. Physiotherapy, rest, exercises, and maintaining an acceptable body weight may improve joint mobility and also contribute to the partial relief of symptoms.32 It is well known that long-term use of anti-inflammatory drugs is not advised as it may cause serious gastro-intestinal, renal, blood or other complications. It could be of tremendous help to use nanotechnology in target-drug delivery. It
could be of great help if anti-inflammatory nanocapsules are used as they provide prolonged treatment to all forms of arthritis. Moreover, it would be beneficial if those nano biologically active materials could be sent directly to the diseased site. It is believed that the targeted drug delivery therapies to specific tissues in a body could be more effective than a drug that is delivered to all body tissues. There is already work on targeted drug delivery therapies for the treatment of cancer. Nanotechnology was able to discover new types of polymers which were shown to physically detect and destroy antibiotic-resistant bacteria and infectious diseases like Methicillin-resistant Staphylococcus aureus, known as MRSA. Therefore, the primary goals for research of nano-biotechnologies in drug targeting and delivery should include a more specific, safe, less toxic and biocompatible drug.33, 34 5.4 Nanotechnology and Nanobiomaterials in
the Treatment of Advanced OA In advanced OA of the joints (Fig. 5.1), surgery is the treatment of choice. Surgical debridement or corrective osteotomies of the pathologic joint are occasionally performed. The most common treatment in patients with severe damage of the articular joints is the total joint replacement, or joint arthroplasty. There are many different types of joint replacements. In hip arthroplasties, the orthopaedic prosthetic implant could be metal-on-polyethylene, metal-on-metal, ceramic-on-ceramic, ceramic-on-polyethylene, etc. The polyethylene component may be either cross-linked or highly cross-linked. Acrylic bone cement is also used to fix the prosthetic implants to the bone of the patient. In this case, two interfaces are created at the site of implant insertion; the bone-cement interface and the cement-implant interface. Most orthopaedic surgeons prefer the use of cementless press fit orthopaedic prosthetic implants. The press fit prosthetic implants are, therefore, in direct contact with the bone and only one bone-implant interface exists. Most of the orthopaedic prosthetic implants used are made of cobalt-chromium or titanium. Most of the epidemiological studies show that total joint arthroplasties are continuously increasing in number and more than 50% of all joint arthroplasties will be expected to be performed in
patients less than 65 years of age. At the current rate of increase in the number of joint replacements, researchers believe that younger patients will account for 52% of all total hip arthroplasties, and 55-62% of all primary and revision total knee arthroplasties, by 2030.35
Figure 5.1 Intraoperative picture of an advanced osteoarthritic knee with the damaged articular surfaces. Joint replacements, are, therefore not always successful; there is a failure rate that may reach 1-2% (Fig. 5.2). The prosthetic implant could fail, loosen, or get infected. Patients with failed joint arthroplasty should be re-operated and this type of operation is called revision arthroplasty. In some patients, more than one revision surgery in their lifetime could be necessary. Metal ions and debris that are released from the different types of prosthetic implants constitute an issue of concern to orthopaedic surgeons, as it is the source of toxicity to different body organs. An ideal orthopaedic prosthetic implant is one that lasts long, does not loosen, and does not produce debris or metal wear. Implants that are less toxic to the body organs and resistant to different types of microorganisms are needed. An ideal implant is the type of prosthesis that adheres and bonds well to bone with minimal or even no fibroblast formation between the interfaces. To achieve all the above, researchers should first understand the relation between the implant and the bone, and second, study the natural cell behaviour
of the bone. In other words, we need prosthetic implants that are more biocompatible.
