Orthopaedic Bone Cements

With an increasing number of bone cements available, it is vital that the correct material is selected for specific clinical procedures. A review of the most recent research in this field, this book covers such topics as hip replacements, verteboplasty and wear particles and osteolysis. It reviews materials and types of cement such as acrylic, polymethylmethacrylate and calcium phosphate cements and address the mechanical properties of bone cements such as fracture toughness and dynamic creep. The book closes with an examination of methods to enhance the properties of bone cements such as antibiotic loaded bone cements and bioactive cements.

Bone cements are widely used in orthopaedic applications to anchor implants to existing bone, reconstruct bone and deliver bioactive agents to the body. With an increasing number of bone cements available, it is vital that the correct material is selected for specific clinical procedures. Orthopaedic bone cements reviews the most recent research in this field. Part one discusses the current uses of orthopaedic bone cements with chapters on such topics as hip replacements, verteboplasty and wear particles and osteolysis. Part two reviews materials and types of cement such as acrylic, polymethylmethacrylate and calcium phosphate cements. Chapters in Part three address the mechanical properties of bone cements such as fracture toughness and dynamic creep. The final section examines methods to enhance the properties of bone cements with coverage of themes such as antibiotic loaded bone cements and bioactive cements. With its eminent editor and multidisciplinary team of international contributors, Orthopaedic bone cements is an invaluable reference for materials scientists, medical researchers and all those involved in the development of bone cements for orthopaedic applications and joint replacement. Provides a review of recent research focussing on improving the mechanical and biological performance of bone cements Discusses the current applications of bone cements particularly in hip replacement, verteboplasty and wear particles Reviews types of materials and acrylic, polymethlymethacrylate and calcium phosphate as types of cements

G. H. I. M. WALENKAMP, D. W. MURRAY Since the first use of bone cement, there has been much discussion about this important tool in arthroplasty. Many authors consider the cemented prosthesis as the gold standard when evaluating the outcome of primary prostheses. In a large number of total hip arthroplasties, as registered in the Scandi navian Hip Registers, important differences in revision risks have been docu mented between hospitals. These differences are partly due to the use of di verse cement techniques. In the analysis of data, the influence of these tech niques, as well as the different cement types, is clear. A recent disaster with a newly developed cement also illustrated that the quality of the cement must be assured, and that the introduction of a new material must be carefully prepared and followed-up. The new Palamed cement has been developed by the makers of the well known Palacos and Refobacin Palacos, which appeared to be the best ce ments in the Swedish register. An improvement was noted in slightly better handling characteristics, but the end product is the same as Palacos. As men tioned, this cement will be carefully followed-up in the near future. However, its introduction is a good reason to gather the expertise of some of the lead ing figures in the field in this book. II History of Bone Cements CHAPTER 2. 1 Industrial Development of Bone Cement Twenty-Five Years of Experience w. EGE, K. D.

The use of antibiotic-loaded bone cement is an established method in the management of periprosthetic hip and knee joint infection. Despite inconsistencies among published studies, mechanical failure and infection are leading causes of failure in early revisions (15.7% and 8.2% for hip; 21% and 7.9% for knee). This study evaluates the effect of antibiotics on mechanical properties, antibacterial properties, and release characteristic when incorporated into the bone cement. These data are needed as a benchmark for the next generation of new antibiotic loaded bone cements and also can be used to develop new formulations. Chapter 3 (Manuscript #1) investigated the mechanical properties of a commercially available bone cement with the addition of vancomycin, to determine the release characteristics and efficacy at eliminating the orthopedic implant pathogens. Palacos®ʼ R was loaded with incrementally larger clinically relevant weight percentages of vancomycin. The addition of vancomycin reduced the bone cement's mechanical properties. Also, vancomycin eluted from Palacos®ʼ R with a steady rise in eluted volume up to 8 days, after which non-therapeutic elution concentrations were observed up to a 60-day end point. The eluted concentration from samples with greater than 0.25 g vancomycin per Palacos®ʼ R packet was sufficient to eliminate a 103 colony forming unit per mL (CFU/mL) initial inoculum of S. aureus, including methicillin-resistant S. aureus (MRSA). Chapter 4 (Manuscript #2) investigated SimplexTM P, a commercially available bone cement with vancomycin. Vancomycin at five different loading masses (0.125, 0.25, 0.5, 1.0 and 2.0 g) was added to 40 grams of SimplexTM P. Addition of vancomycin affected the mechanical properties and antimicrobial activity with significant differences from controls. Flexural and compression mechanical properties were compromised with added vancomycin. The flexural strength of samples with added vancomycin of 0.5 g and greater were not greater than ISO 5833 minimum requirements. 2.0 g of vancomycin added to bone cement was able to eliminate completely the four bacterial strains tested. 2.0 g of vancomycin also showed the highest mass elution from the cement over a 60-day period. Given the reduced flexural strength in samples with 0.5 g and greater of added vancomycin and the inability of vancomycin in amounts less than 2.0 g to eliminate bacteria, this study did not find an ideal amount of vancomycin added to SimplexTM P that meets both strength and antibacterial requirements. Chapter 5 (Manuscript #3) evaluated telavancin elution, stability, and antimicrobial activity when incorporated into the commercial bone cements Palacos℗ʼ R and SimplexTM P. Telavancin at five loading volumes (0.3 vol%, 0.6 vol%, 1.2 vol%, 2.4 vol%, and 4.8 vol%). was added to the two cements. The release characteristics of telavancin were recorded for 60 days to estimate the elution profiles. The efficacy of eluted telavancin for eliminating four common implant pathogens was determined. Mechanical testing was also performed. Telavancin affected the elution, antimicrobial activity, and mechanical properties in a dose-dependent manner. Telavancin added to Palacos®ʼ R at 4.8 vol% was able to eliminate MSSA, MRSA, and S. epidermidis, while the same concentration in SimplexTM P failed to kill all tested strains. Telavancin also exhibited better elution in the former case over a 60-day period. Both cements showed reduced flexural and compression properties with added telavancin. Telavancin loaded to Palacos®ʼ R achieved better efficacy than in SimplexTM P. Under microscopic examination the two cements showed different numbers and size of pores, potentially affecting strength. Telavancin loaded in Palacos℗ʼ R is a promising prophylactic option. However, the feasibility of using telavancin as an alternative to traditional antibiotics in acrylic bone cement requires further consideration due to the unsustained telavancin release and reduced strength. Chapter 6 (Manuscript #4) was a computational investigation of the effect of porosity and its distribution on bone cement fracture toughness. The effect of pores was analyzed using the extended finite element method (X-FEM) crack propagation simulation method with different sizes of pores and locations. Predicted force-displacement behavior and fracture toughness were compared to experimental results. Crack growth and propagation are affected by porosity parameters, for example, pore size an independent parameter and dependent parameters such as pore-pore and pore-crack interactions. These dependent porosity parameters are primarily affected by pore size and pore location. The experimental and simulation results of the current study contribute to a better understanding of the effect of porosity on bone cement fracture toughness.

Cemented Total Hip Arthroplasty (THA) remains one of the most successful procedures in Orthopaedic surgery. It has become very clear that it is the surgical expertise, in particular the quality of the cementing technique, which will affect long-term outcome and success. It is the intention of this book to provide an up-to-date comprehensive assessment of the entire field of cemented THA. Special emphasis has been given to practice-relevant aspects: well-illustrated and detailed operative steps as a practical guideline, a basic science chapter and long-term outcome data are provided. Minimally invasive surgery, modern perioperative management and patient fast tracking are covered. A number of highly respected experts have contributed to this in-depth compilation of the "state of the art" in 2005. This book is written and intended for both, trainees and established arthroplasty surgeons who are dedicated to perform a well-cemented THA.

Written by respected experts in the field, Biomaterials in Orthopedics discusses bioabsorbable biomaterials for bone repair, nondegradable materials in orthopaedics and delivery systems. Topics in this text include biocompatibility and the biomaterial/tissue interface; self-reinforced bioabsorbable devices and guided regeneration; bone substitutes,

This handbook describes several current trends in the development of bioceramics and biocomposites for clinical use in the repair, remodelling, and regeneration of bone tissue. Comprehensive coverage of these materials allows fundamental aspects of the science and engineering to be seen in close relation to the clinical performance of dental and orthopaedic implants. Bioceramics and biocomposites appear to be the most dynamic area of materials development for both tissue engineering and implantable medical devices. Almost all medical specialties will continue to benefit from these developments, but especially dentistry and orthopaedics. In this Handbook, leading researchers describe the use of bionanomaterials to create new functionalities when interfaced with biological molecules or structures. Also described are technologies for bioceramics and biocomposites processing in order to fabricate medical devices for clinical use. Another important section of the book is dedicated to tissue regeneration with development of new matrices. A targeted or personalized treatment device reduces drug consumption and treatment expenses, resulting in benefits to the patient and cost reductions for public health systems. This authoritative reference on the state-of-the-art in the development and use of bioceramics and biocomposites can also serve as the basis of instructional course lectures for audiences ranging from advanced undergraduate students to post-graduates in materials science and engineering and biomedical engineering.