Periprosthetic joint infection (PJI) is one of the most dreaded complications after arthroplasty surgery; thus numerous approaches have been undertaken to equip metal surfaces with antibacterial properties. Due to its antimicrobial effects, silver is a promising coating for metallic surfaces, and several types of silver-coated arthroplasty implants are in clinical use today. However, silver can also exert toxic effects on eukaryotic cells both in the immediate vicinity of the coated implants and systemically. In most clinically-used implants, silver coatings are applied on bulk components that are not in direct contact with bone, such as in partial or total long bone arthroplasties used in tumour or complex revision surgery. These implants differ considerably in the coating method, total silver content, and silver release rates. Safety issues, such as the occurrence of argyria, have been a cause for concern, and the efficacy of silver coatings in terms of preventing PJI is also controversial. The application of silver coatings is uncommon on parts of implants intended for cementless fixation in host bone, but this option might be highly desirable since the modification of implant surfaces in order to improve osteoconductivity can also increase bacterial adhesion. Therefore, an optimal silver content that inhibits bacterial colonization while maintaining osteoconductivity is crucial if silver were to be applied as a coating on parts intended for bone contact. This review summarizes the different methods used to apply silver coatings to arthroplasty components, with a focus on the amount and duration of silver release from the different coatings; the available experience with silver-coated implants that are in clinical use today; and future strategies to balance the effects of silver on bacteria and eukaryotic cells, and to develop silver-coated titanium components suitable for bone ingrowth. Cite this article:
Methicillin-resistant Staphylococcus aureus (MRSA) has become a ubiquitous bacterium in both the hospital and community setting. There are two major subclassifications of MRSA, community-acquired and healthcare-acquired, each with differing pathogenicity and management. MRSA is increasingly responsible for infections in otherwise healthy, active adults. Local outbreaks affect both professional and amateur athletes and there is increasing public awareness of the issue. Health-acquired MRSA has major cost and outcome implications for patients and hospitals. The increasing prevalence and severity of MRSA means that the orthopaedic community should have a basic knowledge of the bacterium, its presentation and options for treatment. This paper examines the evolution of MRSA, analyses the spectrum of diseases produced by this bacterium and presents current prevention and treatment strategies for orthopaedic infections from MRSA.
The dismal outcome of tuberculosis of the spine in the pre-antibiotic era has improved significantly because of the use of potent antitubercular drugs, modern diagnostic aids and advances in surgical management. MRI allows the diagnosis of a tuberculous lesion, with a sensitivity of 100% and specificity of 88%, well before deformity develops. Neurological deficit and deformity are the worst complications of spinal tuberculosis. Patients treated conservatively show an increase in deformity of about 15°. In children, a kyphosis continues to increase with growth even after the lesion has healed. Tuberculosis of the spine is a medical disease which is not primarily treated surgically, but operation is required to prevent and treat the complications. Panvertebral lesions, therapeutically refractory disease, severe kyphosis, a developing neurological deficit, lack of improvement or deterioration are indications for surgery. Patients who present with a kyphosis of 60° or more, or one which is likely to progress, require anterior decompression, posterior shortening, posterior instrumented stabilisation and anterior and posterior bone grafting in the active stage of the disease. Late-onset paraplegia is best prevented rather than treated. The awareness and suspicion of an atypical presentation of spinal tuberculosis should be high in order to obtain a good outcome. Therapeutically refractory cases of tuberculosis of the spine are increasing in association with the presence of HIV and multidrug-resistant tuberculosis.
Polymethylmethacrylate remains one of the most enduring materials in orthopaedic surgery. It has a central role in the success of total joint replacement and is also used in newer techniques such as percutaneous vertebroplasty and kyphoplasty. This article describes the current uses and limitations of polymethylmethacrylate in orthopaedic surgery. It focuses on its mechanical and chemical properties and links these to its clinical performance. The behaviour of antibiotic-loaded bone cement are discussed, together with areas of research that are now shedding light upon the behaviour of this unique biomaterial.
The management of injury to the distal tibiofibular syndesmosis remains controversial in the treatment of ankle fractures. Operative fixation usually involves the insertion of a metallic diastasis screw. There are a variety of options for the position and characterisation of the screw, the type of cortical fixation, and whether the screw should be removed prior to weight-bearing. This paper reviews the relevant anatomy, the clinical and radiological diagnosis and the mechanism of trauma and alternative methods of treatment for injuries to the syndesmosis.
The mammalian growth plate is a complex structure which is essential for the elongation of long bones. However, an understanding of how the growth plate functions at the cellular level is lacking. This review, summarises the factors involved in growth-plate regulation, its failure and the consequence of injury. We also describe some of the cellular mechanisms which underpin the increase in volume of the growth-plate chondrocyte which is the major determinant of the rate and extent of bone lengthening. We show how living in situ chondrocytes can be imaged using 2-photon laser scanning microscopy to provide a quantitative analysis of their volume. This approach should give better understanding of the cellular control of bone growth in both healthy and failed growth plates.
This review discusses the pathogenesis and surgical treatment of tears of the rotator cuff.
Thromboprophylaxis remains a controversial subject. A vast amount of epidemiological and trial data about venous thromboembolism has been published over the past 40 years. These data have been distilled and synthesised into guidelines designed to help the practitioner translate this extensive research into ‘evidence-based’ advice. Guidelines should, in theory, benefit patient care by ensuring that every patient routinely receives the best prophylaxis; without guidelines, it is argued, patients may fail to receive treatment or be exposed to protocols which are ineffective, dangerous or expensive. Guidelines, however, have not been welcomed or applied universally. In the United States, orthopaedic surgeons have published their concerns about the thromboprophylaxis guidelines prepared by the American College of Chest Physicians. In Britain, controversy persists with many surgeons unconvinced of the risk/benefit, cost/benefit or practicality of thromboprophylaxis. The extended remit of the recent National Institute of Clinical Excellence thromboprophylaxis guidelines has been challenged. The reasons for this disquiet are addressed in this paper and particular emphasis is placed on how clinically-acceptable guidelines could be developed and applied.
Despite advances in the prevention and treatment of osteoporotic fractures, their prevalence continues to increase. Their operative treatment remains a challenge for the surgeon, often with unpredictable outcomes. This review highlights the current aspects of management of these fractures and focuses on advances in implant design and surgical technique.
The literature on fracture repair has been reviewed. The traditional concepts of delayed and nonunion have been examined in terms of the phased and balanced anabolic and catabolic responses in bone repair. The role of medical manipulation of these inter-related responses in the fracture healing have been considered.
