G. Maccauro

Fracture of a Y-TZP ceramic femoral head: ANALYSIS OF A FAULT

We studied factors contributing to the initiation of fracture and failure of a zirconia ceramic femoral head. The materials retrieved during a revision total hip replacement were submitted to either visual, stereomicroscopic and scanning electron microscopy (SEM) or SEM and energy-dispersive X-ray analysis. X-ray diffraction was performed in order to investigate the extent of tetragonal to monoclinic phase transition. Histological examination was performed on the periprosthetic tissues. The results showed that failure was due to the propagation during clinical use of defects which may have been introduced into the material during the processing of the ceramic, rather than those intrinsic to zirconia. The literature relating to previous failures of zirconia components is reviewed.

Nutrition and cancer prevention

Cancer cells invade surrounding tissues and metastasize to distant sites. Diet high in fat is a strong link to, and perhaps causes, a high incidence of tumours. Trans-fatty acid might impair the function and it could be involved in the development of cancer. Cholesterol is also strongly suspected to be involved in the development of tumours, therefore it is important for everyone to eat well, especially for people with cancer to prevent the body tissues from breaking down and helping to rebuild the normal tissue that may have been affected by the treatments. Factors secreted by adipocytes and macrophages such as TNF-alpha and other inflammatory proteins are involved in inflammation in cancer. In addition, MCSF which up-regulates adipocyte tissue is also important for the stimulation of fat cell proliferation and is expressed by human adipocytes. Many cytokines, such as IL-1, IL-6, IL-8, IL-32, IL-33 and MCP-1, are biomarkers for cancer and chronic diseases along with transcription factors NFkB and AP-1; these last two factors are important bioactive substances on the molecular mechanism of the control of genes which in turn affect cellular metabolism. In this paper we revisit the interrelationship between cancer and metabolism.

Physiopathology of spine metastasis.

The metastasis is the spread of cancer from one part of the body to another. Two-thirds of patients with cancer will develop bone metastasis. Breast, prostate and lung cancer are responsible for more than 80% of cases of metastatic bone disease. The spine is the most common site of bone metastasis. A spinal metastasis may cause pain, instability and neurological injuries. The diffusion through Batson venous system is the principal process of spinal metastasis, but the dissemination is possible also through arterial and lymphatic system or by contiguity. Once cancer cells have invaded the bone, they produce growth factors that stimulate osteoblastic or osteolytic activity resulting in bone remodeling with release of other growth factors that lead to a vicious cycle of bone destruction and growth of local tumour.

Stimulation of Bone Formation and Fracture Healing with Pulsed Electromagnetic Fields: Biologic Responses and Clinical Implications

Pulsed electromagnetic fields (PEMF) have been used for several years to supplement bone healing. However, the mode of action of this non-invasive method is still debated and quantification of its effect on fracture healing is widely varied. At cellular and molecular level, PEMF has been advocated to promote the synthesis of extracellular matrix proteins and exert a direct effect on the production of proteins that regulate gene transcription. Electromagnetic fields may also affect several membrane receptors and stimulate osteoblasts to secrete several growth factors such as bone morphogenic proteins 2 and 4 and TGF-beta. They could also accelerate intramedullary angiogenesis and improve the load to failure and stiffness of the bone. Although healing rates have been reported in up to 87% of delayed unions and non-unions,.the efficacy of the method is significantly varied while patient or fracture related variables could not be clearly associated with a successful outcome.

Platelet rich plasma and tendinopathy: state of the art.

Platelet-rich plasma (PRP) is increasingly used in the management of tendon injury in sports, supposedly accelerating the process of healing, tissue regeneration, and return to play. However, the scientific clinical evidence to support its use is scanty, and more level I studies need to be performed to justify its widespread use.

IL-37 (IL-1F7) the newest anti-inflammatory cytokine which suppresses immune responses and inflammation.

Cytokines such as interleukins, chemokines and interferons are immunomodulating and inflammatory agents, characterized by considerable redundancy, in that many cytokines appear to share similar functions. Virtually all nucleated cells, but especially epithelial cells and macrophages, are potent producers of cytokines. The objective of this study is to review the detailed mechanism of action and the biological profiles of IL-37, the newest anti-inflammatory cytokine. This review focuses on IL-37, a key cytokine in regulating inflammatory responses, mainly by inhibiting the expression, production and function of proinflammatory cytokines: IL-1 family pro-inflammatory effects are markedly suppressed by IL-37.

Surgical treatment of pathologic fractures of humerus

This study evaluates different operative treatment options for patients with metastatic fractures of the humerus focusing on surgical procedures, complications, function, and survival rate. From January 2003 to January 2008, 87 pathological fractures of the humerus in 85 cancer patients were surgically treated in our institutions. Histotypes were breast (n=21), lung (n=14), prostate (n=5), bladder (n=4), kidney (n=13), thyroid (n=7), larynx (n=1), lymphoma (n=5), myeloma (n=8), colon-rectum (n=1), melanoma (n=1), testicle (n=1), hepatocellular carcinoma (n=1) and unknown tumours (n=3). Lesions of the proximal epiphysis were treated with resection and endoprosthetic replacement (n=30). The remaining 57 fractures were stabilized with antegrade unreamed intra-medullary locked nailing without (9 cases) or with resection and use of cement (48 cases). The function of the upper limb was assessed using the Musculo-Skeletal Tumor Society (MSTS) rating scale and survival rate was retrospectively analysed. The mean survival time of patients after surgery was 8.3 months. Complications of endoprosthetic replacement recorded included disease relapse (n=3), soft tissue infection (n=2) and palsy of musculocutaneous nerve (n=1) whereas, for intra-medullary locked nailing there were three cases of soft tissue infection and one case of radial nerve palsy. The mean MSTS score at follow-up was 73% for endoprosthesis and 79.2% for locked intra-medullary nailing. Endoprosthetic replacement of the proximal humerus provides a good function of the upper limb, a low risk of local relapse with a low complication rate at follow-up. Unreamed nailing provides immediate stability and pain relief, minimum morbidity and early return of function.

Percutaneous acetabuloplasty for metastatic acetabular lesions

BackgroundOsteolytic metastases around the acetabulum are frequent in tumour patients, and may cause intense and drug-resistant pain of the hip. These lesions also cause structural weakening of the pelvis, limping, and poor quality of life. Percutaneous acetabuloplasty is a mini-invasive procedure for the management of metastatic lesions due to carcinoma of the acetabulum performed in patients who cannot tolerate major surgery, or in patients towards whom radiotherapy had already proved ineffective.MethodsWe report a retrospective study in 25 such patients (30 acetabuli) who were evaluated before and after percutaneous acetabuloplasty, with regard to pain, mobility of the hip joint, use of analgesics, by means of evaluation forms: Visual Analog Scale, Harris Hip Score, Western Ontario and McMaster Universities Index of Osteoarthritis (WOMAC), Eastern Cooperative Oncology Group (ECOG). The results obtained were analysed using the χ2 Test and Fishers exact test. Significance was sent at P < 0.05.ResultsMarked clinical improvement was observed in all patients during the first six post-operative months, with gradual a worsening thereafter from deterioration of their general condition.Complete pain relief was achieved in 15 of our 25 (59%) of patients, and pain reduction was achieved in the remaining 10 (41%) patients. The mean duration of pain relief was 7.3 months. Pain recurred in three patients (12%) between 2 weeks to 3 months. No major complications occurred. There was transient local pain in most cases, and 2 cases of venous injection of cement without clinical consequences.ConclusionPercutaneous acetabuloplasty is effective in improving the quality of life of patients with osteolytic bone tumours, even though the improvement is observed during the first 6 months only. It can be an effective aid to chemo- and radiotherapy in the management of acetabular metastases.

Atherosclerosis: a classic inflammatory disease.

Atherosclerosis is an inflammatory disease due to a diet high in saturated fat, hypercholesterolemia, obesity, hypoglycemia, etc. mainly mediated by the infiltration of macrophage and T cells into the vascular wall. Once the endothelial is damaged monocytes penetrate the tissue and are transformed in scavenger cells. Upon stimulation of Th1 cells, a group of cytokines is released and contributes to the inflammatory response of atherosclerotic tissue. When macrophages proliferate they amplify inflammatory response through the secretion of growth factors and cytokines such as TNF and IL-1. In addition, chemokines such as RANTES and other C-C chemokines are generated, and matrix metalloprotinease 9 (MMP-9) are produced by activated monocytes. However, the immune system in atherosclerosis still remains unclear. Here, in this study we revisited the inter-relationship between atherosclerosis and inflammation.

Development of a new zirconia-toughened alumina: promising mechanical properties and absence of in vitro carcinogenicity.

High purity alumina as well as zirconia ceramics have been widely used as orthopaedic implant biomaterials and dental devices displaying optimal, but sometimes exclusive, mechanical properties. In order to combine the advantages of alumina and zirconia ceramic materials different types of composites have been developed in which either zirconia is dispersed in an alumina matrix or vice versa. Orthopaedic and dental implant biomaterials are expected to be in contact with living tissues for a long period of time and their long term toxicity must be carefully evaluated. In this study we report the development of a high performance chromia-doped Zirconia Toughened Alumina (ZTA) material which displays promising mechanical properties in terms of hardness, strength and fracture toughness that make it suitable for prosthesis even for small joints. The long-term biocompatibility of this material was also evaluated, mainly in terms of DNA damage, mutagenicity and cancerogenetic potential in mammalian cells. The results obtained suggest that this new ZTA material does not display any long-term carcinogenic effect and it is suitable for biomedical applications from a cancerogenetic point of view. In conclusion, we report the development of a new chromia-doped ZTA material with interesting properties both from a mechanical and a biocompatibility point of view which warrant further studies on its suitability as a candidate biomaterial for orthopaedic implants and dental devices.