We undertook a review of the literature relating to the two basic stem designs in use in cemented hip replacement, namely loaded tapers or force-closed femoral stems, and the composite beam or shape-closed designs. The associated stem fixation theory as understood from in vitro studies and finite element modelling were examined with reference to the survivorship results for each of the concepts of fixation. It is clear that both design principles are capable of producing successful long-term results, providing that their specific requirements of stem metallurgy, shape and surface finish, preparation of the bone and handling of the cement are observed

Adolescent idiopathic scoliosis (AIS), defined by an age at presentation of 11 to 18 years, has a prevalence of 0.47% and accounts for approximately 90% of all cases of idiopathic scoliosis. Despite decades of research, the exact aetiology of AIS remains unknown. It is becoming evident that it is the result of a complex interplay of genetic, internal, and environmental factors. It has been hypothesized that genetic variants act as the initial trigger that allow epigenetic factors to propagate AIS, which could also explain the wide phenotypic variation in the presentation of the disorder. A better understanding of the underlying aetiological mechanisms could help to establish the diagnosis earlier and allow a more accurate prediction of deformity progression. This, in turn, would prompt imaging and therapeutic intervention at the appropriate time, thereby achieving the best clinical outcome for this group of patients.

Cite this article: Bone Joint J 2022;104-B(8):915–921.

Aims

The aim of this study was to prepare a scoping review to investigate the use of biologic therapies in the treatment of musculoskeletal injuries in professional and Olympic athletes.

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: Bone Joint J 2021;103-B(3):423–429.

The survivorship of contemporary resurfacing arthroplasty of the hip using metal-on-metal bearings is better than that of first generation designs, but short-term failures still occur. The most common reasons for failure are fracture of the femoral neck, loosening of the component, osteonecrosis of the femoral head, reaction to metal debris and malpositioning of the component. In 2008 the Australian National Joint Registry reported an inverse relationship between the size of the head component and the risk of revision in resurfacing hip arthroplasty. Hips with a femoral component size of ≤ 44 mm have a fivefold increased risk of revision than those with femoral components of ≥ 55 mm irrespective of gender. We have reviewed the literature to explore this observation and to identify possible reasons including the design of the implant, loading of the femoral neck, the orientation of the component, the production of wear debris and the effects of metal ions, penetration of cement and vascularity of the femoral head. Our conclusion is that although multifactorial, the most important contributors to failure in resurfacing arthroplasty of the hip are likely to be the design and geometry of the component and the orientation of the acetabular component

A modular femoral head–neck junction has practical advantages in total hip replacement. Taper fretting and corrosion have so far been an infrequent cause of revision. The role of design and manufacturing variables continues to be debated. Over the past decade several changes in technology and clinical practice might result in an increase in clinically significant taper fretting and corrosion. Those factors include an increased usage of large diameter (36 mm) heads, reduced femoral neck and taper dimensions, greater variability in taper assembly with smaller incision surgery, and higher taper stresses due to increased patient weight and/or physical activity. Additional studies are needed to determine the role of taper assembly compared with design, manufacturing and other implant variables. . Cite this article: Bone Joint J 2013;95-B, Supple A:3–6

Although the importance of sound statistical principles in the design and analysis of data has gained prominence in recent years, biostatistics, the application of statistics to the analysis of biological and medical data, is still a subject which is poorly understood and often mishandled. This review introduces, in the context of orthopaedic research, the terminology and the principles involved in simple data analysis, and outlines areas of medical statistics that have gained prominence in recent years. It also lists and provides an insight into some of the more common errors that occur in published orthopaedic journals and which are frequently encountered at the review stage in papers submitted to the Journal of Bone and Joint Surgery

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 management of bone loss in revision replacement of the knee remains a challenge despite an array of options available to the surgeon. Bone loss may occur as a result of the original disease, the design of the prosthesis, the mechanism of failure or technical error at initial surgery. The aim of revision surgery is to relieve pain and improve function while addressing the mechanism of failure in order to reconstruct a stable platform with transfer of load to the host bone. Methods of reconstruction include the use of cement, modular metal augmentation of prostheses, custom-made, tumour-type or hinged implants and bone grafting. The published results of the surgical techniques are summarised and a guide for the management of bone defects in revision surgery of the knee is presented

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

Hip implant retrieval analysis is the most important source of insight into the performance of new materials and designs of hip arthroplasties. Even the most rigorous in vitro testing will not accurately simulate the behavior of implant materials and new designs of prosthetic arthroplasties. Retrieval analysis has revealed such factors as the effects of gamma-in-air sterilisation of polyethylene, fatigue failure mechanisms of polymethylmethacrylate bone cement, fretting corrosion of Morse taper junctions, third body wear effects of both hard-on-hard and hard-on-soft bearing couples, and the effects of impingement of components on the full spectrum of bearing surfaces, none of which was predicted by pre-implantation in vitro testing of these materials and combinations. The temporal sequence of the retrieval process is approximately six years from first implantation through retrieval analysis, laboratory investigation, and publication of results, and thus, in addition to rigorous clinical evaluation, represents the true development and insight cycle for new designs and materials.

Biochemical markers of bone-turnover have long been used to complement the radiological assessment of patients with metabolic bone disease. Their implementation in daily clinical practice has been helpful in the understanding of the pathogenesis of osteoporosis, the selection of the optimal dose and the understanding of the progression of the onset and resolution of treatment. Since they are derived from both cortical and trabecular bone, they reflect the metabolic activity of the entire skeleton rather than that of individual cells or the process of mineralisation.

Quantitative changes in skeletal-turnover can be assessed easily and non-invasively by the measurement of bone-turnover markers. They are commonly subdivided into three categories; 1) bone-resorption markers, 2) osteoclast regulatory proteins and 3) bone-formation markers. Because of the rapidly accumulating new knowledge of bone matrix biochemistry, attempts have been made to use them in the interpretation and characterisation of various stages of the healing of fractures. Early knowledge of the individual progress of a fracture could help to avoid delayed or nonunion by enabling modification of the host’s biological response.

The levels of bone-turnover markers vary throughout the course of fracture repair with their rates of change being dependent on the size of the fracture and the time that it will take to heal. However, their short-term biological variability, the relatively low bone specificity exerted, given that the production and destruction of collagen is not limited to bone, as well as the influence of the host’s metabolism on their concentration, produce considerable intra- and inter-individual variability in their interpretation. Despite this, the possible role of bone-turnover markers in the assessment of progression to union, the risks of delayed or nonunion and the impact of innovations to accelerate fracture healing must not be ignored.

Neurological conditions affecting the hip pose a considerable challenge in replacement surgery since poor and imbalanced muscle tone predisposes to dislocation and loosening. Consequently, total hip replacement (THR) is rarely performed in such patients. In a systematic review of the literature concerning THR in neurological conditions, we found only 13 studies which described the outcome. We have reviewed the evidence and discussed the technical challenges of this procedure in patients with cerebral palsy, Parkinson’s disease, poliomyelitis and following a cerebrovascular accident, spinal injury or development of a Charcot joint. Contrary to traditional perceptions, THR can give a good outcome in these often severly disabled patients.

Fractures of the proximal interphalangeal joint include a wide spectrum of injuries, from stable avulsion fractures to complex fracture-dislocations. Stability of the joint is paramount in determining the appropriate treatment, which should aim to facilitate early mobilisation and restoration of function.

Failure of bone repair is a challenging problem in the management of fractures. There is a limited supply of autologous bone grafts for treating nonunions, with associated morbidity after harvesting. There is need for a better source of cells for repair. Mesenchymal stem cells (MSCs) hold promise for healing of bone because of their capacity to differentiate into osteoblasts and their availability from a wide variety of sources. Our review aims to evaluate the available clinical evidence and recent progress in strategies which attempt to use autologous and heterologous MSCs in clinical practice, including genetically-modified MSCs and those grown on scaffolds. We have compared various procedures for isolating and expanding a sufficient number of MSCs for use in a clinical setting.

There are now a number of clinical studies which have shown that implantation of MSCs is an effective, safe and durable method for aiding the repair and regeneration of bone.

The advent of computer-assisted knee replacement surgery has focused interest on the alignment of the components. However, there is confusion at times between the alignment of the limb as a whole and that of the components. The interaction between them is discussed in this article. Alignment is expressed relative to some reference axis or plane and measurements will vary depending on what is selected as the reference. The validity of different reference axes is discussed. Varying prosthetic alignment has direct implications for surrounding soft-tissue tension. In this context the interaction between alignment and soft-tissue balance is explored and the current knowledge of the relationship between alignment and outcome is summarised.

Most proximal humeral fractures are stable injuries of the ageing population, and can be successfully treated non-operatively. The management of the smaller number of more complex displaced fractures is more controversial and new fixation techniques have greatly increased the range of fractures that may benefit from surgery.

This article explores current concepts in the classification and clinical aspects of these injuries, reviewing the indications, innovations and outcomes for the most common methods of treatment.

This review discusses the causes, outcome and prevention of whiplash injury, which costs the economy of the United Kingdom approximately £3.64 billion per annum. Most cases occur as the result of rear-end vehicle collisions at speeds of less than 14 mph. Patients present with neck pain and stiffness, occipital headache, thoracolumbar back pain and upper-limb pain and paraesthesia. Over 66% make a full recovery and 2% are permanently disabled. The outcome can be predicted in 70% after three months.

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.