Objectives. Taper junctions between modular hip arthroplasty femoral heads and stems fail by wear or corrosion which can be caused by relative motion at their interface. Increasing the assembly force can reduce relative motion and corrosion but may also damage surrounding tissues. The purpose of this study was to determine the effects of increasing the impaction energy and the stiffness of the impactor tool on the stability of the taper junction and on the forces transmitted through the patient’s surrounding tissues. Methods. A commercially available impaction tool was modified to assemble components in the laboratory using impactor tips with varying stiffness at different applied energy levels. Springs were mounted below the modular components to represent the patient. The pull-off force of the head from the stem was measured to assess stability, and the displacement of the springs was measured to assess the force transmitted to the patient’s tissues. Results. The pull-off force of the head increased as the stiffness of the impactor tip increased but without increasing the force transmitted through the springs (patient). Increasing the impaction energy increased the pull-off force but also increased the force transmitted through the springs. Conclusions. To limit wear and corrosion, manufacturers should maximize the stiffness of the impactor tool but without damaging the surface of the head. This strategy will maximize the stability of the head on the stem for a given applied energy, without influencing the force transmitted through the patient’s tissues. Current impactor designs already appear to approach this limit. Increasing the applied energy (which is dependent on the mass of the hammer and square of the contact speed) increases the stability of the modular connection but proportionally increases the force transmitted through the patient’s tissues, as well as to the surface of the head, and should be restricted to safe levels. Cite this article: A. Krull, M. M. Morlock, N. E. Bishop. Maximizing the fixation strength of modular components by impaction without tissue damage. Bone Joint Res 2018;7:196–204. DOI: 10.1302/2046-3758.72.BJR-2017-0078.R2

Objectives

Metal-on-metal (MoM) hip resurfacing was introduced into clinical practice because it was perceived to be a better alternative to conventional total hip replacement for young and active patients. However, an increasing number of reports of complications have arisen focusing on design and orientation of the components, the generation of metallic wear particles and serum levels of metallic ions. The procedure introduced a combination of two elements: large-dimension components and hard abrasive particles of metal wear. The objective of our study was to investigate the theory that microseparation of the articular surfaces draws in a high volume of bursal fluid and its contents into the articulation, and at relocation under load would generate high pressures of fluid ejection, resulting in an abrasive water jet.

Aims. Inadvertent soft tissue damage caused by the oscillating saw during total knee arthroplasty (TKA) occurs when the sawblade passes beyond the bony boundaries into the soft tissue. The primary objective of this study is to assess the risk of inadvertent soft tissue damage during jig-based TKA by evaluating the excursion of the oscillating saw past the bony boundaries. The second objective is the investigation of the relation between this excursion and the surgeon’s experience level. Methods. A conventional jig-based TKA procedure with medial parapatellar approach was performed on 12 cadaveric knees by three experienced surgeons and three residents. During the proximal tibial resection, the motion of the oscillating saw with respect to the tibia was recorded. The distance of the outer point of this cutting portion to the edge of the bone was defined as the excursion of the oscillating saw. The excursion of the sawblade was evaluated in six zones containing the following structures: medial collateral ligament (MCL), posteromedial corner (PMC), iliotibial band (ITB), lateral collateral ligament (LCL), popliteus tendon (PopT), and neurovascular bundle (NVB). Results. The mean 75. th. percentile value of the excursion of all cases was mean 2.8 mm (SD 2.9) for the MCL zone, mean 4.8 mm (SD 5.9) for the PMC zone, mean 3.4 mm (SD 2.0) for the ITB zone, mean 6.3 mm (SD 4.8) for the LCL zone, mean 4.9 mm (SD 5.7) for the PopT zone, and mean 6.1 mm (SD 3.9) for the NVB zone. Experienced surgeons had a significantly lower excursion than residents. Conclusion. This study showed that the oscillating saw significantly passes the edge of the bone during the tibial resection in TKA, even in experienced hands. While reported neurovascular complications in TKA are rare, direct injury to the capsule and stabilizing structures around the knee is a consequence of the use of a hand-held oscillating saw when making the tibial cut. Cite this article: Bone Joint J 2020;102-B(10):1324–1330

Aims

The aim of this study was to determine the fracture haematoma (fxH) proteome after multiple trauma using label-free proteomics, comparing two different fracture treatment strategies.

Aims

Metal particles detached from metal-on-metal hip prostheses (MoM-THA) have been shown to cause inflammation and destruction of tissues. To further explore this, we investigated the histopathology (aseptic lymphocyte-dominated vasculitis-associated lesions (ALVAL) score) and metal concentrations of the periprosthetic tissues obtained from patients who underwent revision knee arthroplasty. We also aimed to investigate whether accumulated metal debris was associated with ALVAL-type reactions in the synovium.

Aims

The efficacy of saline irrigation for treatment of implant-associated infections is limited in the presence of porous metallic implants. This study evaluated the therapeutic efficacy of antibiotic doped bioceramic (vancomycin/tobramycin-doped polyvinyl alcohol composite (PVA-VAN/TOB-P)) after saline wash in a mouse infection model implanted with titanium cylinders.

Aims. Fretting and corrosion at the modular head/neck junction, known as trunnionosis, in total hip arthroplasty (THA) is a cause of adverse reaction to metal debris (ARMD). We describe the outcome of revision of metal-on-polyethylene (MoP) THA for ARMD due to trunnionosis with emphasis on the risk of major complications. Patients and Methods. A total of 36 patients with a MoP THA who underwent revision for ARMD due to trunnionosis were identified. Three were excluded as their revision had been to another metal head. The remaining 33 were revised to a ceramic head with a titanium sleeve. We describe the presentation, revision findings, and risk of complications in these patients. Results. The patients presented with pain, swelling, stiffness, or instability and an inflammatory mass was confirmed radiologically. Macroscopic material deposition on the trunnion was seen in all patients, associated with ARMD. Following revision, six (18.2%) dislocated, requiring further revision in four. Three (9.1%) developed a deep infection and six (18.2%) had significant persistent pain without an obvious cause. One developed a femoral artery thrombosis after excision of an iliofemoral pseudotumor, requiring a thrombectomy. Conclusion. The risk of serious complications following revision MoP THA for ARMD associated with trunnionosis is high. In the presence of extensive tissue damage, a constrained liner or dual mobility construct is recommended in these patients. Cite this article: Bone Joint J 2018;100-B:720–4

Aims

This study aims to assess the relationship between history of pseudotumour formation secondary to metal-on-metal (MoM) implants and periprosthetic joint infection (PJI) rate, as well as establish ESR and CRP thresholds that are suggestive of infection in these patients. We hypothesized that patients with a pseudotumour were at increased risk of infection.

Aims

Although low-intensity pulsed ultrasound (LIPUS) combined with disinfectants has been shown to effectively eliminate portions of biofilm in vitro, its efficacy in vivo remains uncertain. Our objective was to assess the antibiofilm potential and safety of LIPUS combined with 0.35% povidone-iodine (PI) in a rat debridement, antibiotics, and implant retention (DAIR) model of periprosthetic joint infection (PJI).

Aims

CRP is an acute-phase protein that is used as a biomarker to follow severity and progression in infectious and inflammatory diseases. Its pathophysiological mechanisms of action are still poorly defined. CRP in its pentameric form exhibits weak anti-inflammatory activity. The monomeric isoform (mCRP) exerts potent proinflammatory properties in chondrocytes, endothelial cells, and leucocytes. No data exist regarding mCRP effects in human intervertebral disc (IVD) cells. This work aimed to verify the pathophysiological relevance of mCRP in the aetiology and/or progression of IVD degeneration.

Aims

Rheumatoid arthritis (RA) is a common chronic immune disease. Berberine, as its main active ingredient, was also contained in a variety of medicinal plants such as Berberaceae, Buttercup, and Rutaceae, which are widely used in digestive system diseases in traditional Chinese medicine with anti-inflammatory and antibacterial effects. The aims of this article were to explore the therapeutic effect and mechanism of berberine on rheumatoid arthritis.

Aims

To explore the efficacy of extracorporeal shockwave therapy (ESWT) in the treatment of osteochondral defect (OCD), and its effects on the levels of transforming growth factor (TGF)-β, bone morphogenetic protein (BMP)-2, -3, -4, -5, and -7 in terms of cartilage and bone regeneration.

Aims

To test the hypothesis that reseeded anterior cruciate ligament (ACL)-derived cells have a better ability to survive and integrate into tendon extracellular matrix (ECM) and accelerate the ligamentization process, compared to adipose-derived mesenchymal stem cells (ADMSCs).

Aims

This study aimed to explore the biological and clinical importance of dysregulated key genes in osteoarthritis (OA) patients at the cartilage level to find potential biomarkers and targets for diagnosing and treating OA.

Aims

To fully quantify the effect of posterior tibial slope (PTS) angles on joint kinematics and contact mechanics of intact and anterior cruciate ligament-deficient (ACLD) knees during the gait cycle.

Aims

Insufficient treatment response in rheumatoid arthritis (RA) patients requires novel treatment strategies to halt disease progression. The potential benefit of combination of cytokine-inhibitors in RA is still unclear and needs further investigation. To explore the impact of combined deficiency of two major cytokines, namely interleukin (IL)-1 and IL-6, in this study double deficient mice for IL-1αβ and IL-6 were investigated in different tumour necrosis factor (TNF)-driven inflammatory bone disorders, namely peripheral arthritis and sacroiliitis, as well as systemic bone loss.

Osteoarthritis (OA) is a degenerative disease resulting from progressive joint destruction caused by many factors. Its pathogenesis is complex and has not been elucidated to date. Advanced glycation end products (AGEs) are a series of irreversible and stable macromolecular complexes formed by reducing sugar with protein, lipid, and nucleic acid through a non-enzymatic glycosylation reaction (Maillard reaction). They are an important indicator of the degree of ageing. Currently, it is considered that AGEs accumulation in vivo is a molecular basis of age-induced OA, and AGEs production and accumulation in vivo is one of the important reasons for the induction and acceleration of the pathological changes of OA. In recent years, it has been found that AGEs are involved in a variety of pathological processes of OA, including extracellular matrix degradation, chondrocyte apoptosis, and autophagy. Clearly, AGEs play an important role in regulating the expression of OA-related genes and maintaining the chondrocyte phenotype and the stability of the intra-articular environment. This article reviews the latest research results of AGEs in a variety of pathological processes of OA, to provide a new direction for the study of OA pathogenesis and a new target for prevention and treatment.

Cite this article: Bone Joint Res 2022;11(5):292–300.

The use of ultrasound-guided wire localisation of lesions is not well described in the orthopaedic literature. We describe a case of an impalpable schwannoma of the femoral nerve and another of sacroiliitis with an associated pelvic abscess. In both, surgical localisation was difficult. Peri-operative ultrasound-guided wire localisation was used to guide surgery and minimise tissue damage, thereby optimising the results and recovery of the patient

Aims

Prompt and sufficient broad-spectrum empirical antibiotic treatment is key to preventing infection following open tibial fractures. Succeeding co-administration, we dynamically assessed the time for which vancomycin and meropenem concentrations were above relevant epidemiological cut-off (ECOFF) minimal inhibitory concentrations (T > MIC) in tibial compartments for the bacteria most frequently encountered in open fractures. Low and high MIC targets were applied: 1 and 4 µg/ml for vancomycin, and 0.125 and 2 µg/ml for meropenem.

Aims

Complex fractures of the femur and tibia with associated severe soft tissue injury are often devastating for the individual. The aim of this study was to describe the two-year patient-reported outcomes of patients in a civilian population who sustained a complex fracture of the femur or tibia with a Mangled Extremity Severity Score (MESS) of ≥ 7, whereby the score ranges from 2 (lowest severity) to 11 (highest severity).

Although mechanical stabilisation has been a hallmark of orthopaedic surgical management, orthobiologics are now playing an increasing role. Platelet-rich plasma (PRP) is a volume of plasma fraction of autologous blood having platelet concentrations above baseline. The platelet α granules are rich in growth factors that play an essential role in tissue healing, such as transforming growth factor-β, vascular endothelial growth factor, and platelet-derived growth factor. PRP is used in various surgical fields to enhance bone and soft-tissue healing by placing supraphysiological concentrations of autologous platelets at the site of tissue damage. The easily obtainable PRP and its possible beneficial outcome hold promise for new regenerative treatment approaches. The aim of this literature review was to describe the bioactivities of PRP, to elucidate the different techniques for PRP preparation, to review animal and human studies, to evaluate the evidence regarding the use of PRP in trauma and orthopaedic surgery, to clarify risks, and to provide guidance for future research

Aims

Surgical treatment of young femoral neck fractures often requires an open approach to achieve an anatomical reduction. The application of a calcar plate has recently been described to aid in femoral neck fracture reduction and to augment fixation. However, application of a plate may potentially compromise the regional vascularity of the femoral head and neck. The purpose of this study was to investigate the effect of calcar femoral neck plating on the vascularity of the femoral head and neck.

1. A patient wholly insensitive to painful stimuli as judged by psychical, physical, reflex and autonomic responses, showed multiple arthropathies. 2. Biopsy specimens of skin and periosteum from the region of the hip joint showed free nerve terminals similar in morphology to endings considered to subserve pain in normal subjects. The abnormality related to defective pain sensation therefore appears not to be due to a defect in the peripheral nerve endings for pain, but to be located more centrally in the nervous system. 3. In this patient, and in some patients with syringomyelia, arthropathy is associated with selective impairment of pain sensibility of the involved joints. It appears that tissue damage from the wear and tear of normal activity of a joint, if this damage is unheralded because of impairment of pain sense, can lead to arthropathy. 4. It is noted that further experimental evidence is still required to elucidate the role of various modalities of innervation in the maintenance of normal structure and function of joints

Aims

Arthroplasty has become increasingly popular to treat end-stage ankle arthritis. Iatrogenic posterior neurovascular and tendinous injury have been described from saw cuts. However, it is hypothesized that posterior ankle structures could be damaged by inserting tibial guide pins too deeply and be a potential cause of residual hindfoot pain.

Aims

No randomized comparative study has compared the extensile lateral approach (ELA) and sinus tarsi approach (STA) for Sanders type 2 calcaneal fractures. This randomized comparative study was conducted to confirm whether the STA was prone to fewer wound complications than the ELA.

We investigated the effects of low-intensity pulsed ultrasound on distraction osteogenesis in a rabbit model. Callotasis of the right tibia was performed in 70 male Japanese white rabbits using mini-external fixators. In the first part of the study in 64 animals using normal distraction (waiting period seven days; distraction rate 0.5 mm/12 hours; distraction period ten days), we evaluated the distraction site by radiography, measurement of the bone mineral density (BMD), mechanical testing, and histology. In the second part in six rabbits using fast distraction (waiting period 0 days; distraction rate 1.5 mm/12 hours; distraction period seven days) the site was evaluated radiologically. Half of the animals (35) had received ultrasound to their right leg (30mW/cm. 2. ) for 20 minutes daily after ceasing distraction (ultrasound group), while rigid fixation only was maintained in the other half (control group). With normal distraction, the hard callus area, as shown by radiography, the BMD, and the findings on mechanical testing, were significantly greater in those receiving ultrasound than in the control group. Histological analysis showed no tissue damage attributable to exposure to ultrasound. With fast distraction, immature bone regeneration was observed radiologically in the control group, while bone maturation was achieved in the ultrasound group. We conclude that ultrasound can accelerate bone maturation in distraction osteogenesis in rabbits, even in states of poor callotasis

Elevated levels of circulating cobalt ions have been linked with a wide range of systemic complications including neurological, endocrine, and cardiovascular symptoms. Case reports of patients with elevated blood cobalt ions have described significant cardiovascular complications including cardiomyopathy. However, correlation between the actual level of circulating cobalt and extent of cardiovascular injury has not previously been performed. This review examines evidence from the literature for a link between elevated blood cobalt levels secondary to metal-on-metal (MoM) hip arthroplasties and cardiomyopathy. Correlation between low, moderate, and high blood cobalt with cardiovascular complications has been considered. Elevated blood cobalt at levels over 250 µg/l have been shown to be a risk factor for developing systemic complications and published case reports document cardiomyopathy, cardiac transplantation, and death in patients with severely elevated blood cobalt ions. However, it is not clear that there is a hard cut-off value and cardiac dysfunction may occur at lower levels. Clinical and laboratory research has found conflicting evidence of cobalt-induced cardiomyopathy in patients with MoM hips. Further work needs to be done to clarify the link between severely elevated blood cobalt ions and cardiomyopathy.

Cite this article: Bone Joint Res 2021;10(6):340–347.

Aims

The purpose of this study was to examine the efficacy and safety of carbazochrome sodium sulfonate (CSS) combined with tranexamic acid (TXA) on blood loss and inflammatory responses after primary total hip arthroplasty (THA), and to investigate the influence of different administration methods of CSS on perioperative blood loss during THA.

Evidence suggests that the alleviation of pain is enhancedby a strong patient-clinician relationship and attending to a patient’s social and mental health. There is a limited role for medication, opioids in particular.

Orthopaedic surgeons can use comprehensive biopsychosocial strategies to help people recover and can work with colleagues who have the appropriate expertise in order to maximize pain alleviation with optimal opioid stewardship.

Preparing patients for elective surgery and caring for them after unplanned injury or surgery can benefit from planned and practiced strategies based in communication science.

Cite this article: Bone Joint J 2020;102-B(9):1122–1127.

A major pathway of closed soft-tissue injury is failure of microvascular perfusion combined with a persistently enhanced inflammatory response. We therefore tested the hypothesis that hypertonic hydroxyethyl starch (HS/HES) effectively restores microcirculation and reduces leukocyte adherence after closed soft-tissue injury. We induced closed soft-tissue injury in the hindlimbs of 14 male isoflurane-anaesthetised rats. Seven traumatised animals received 7.5% sodium chloride-6% HS/HES and seven isovolaemic 0.9% saline (NS). Six non-injured animals did not receive any additional fluid and acted as a control group. The microcirculation of the extensor digitorum longus muscle (EDL) was quantitatively analysed two hours after trauma using intravital microscopy and laser Doppler flowmetry, i.e. erythrocyte flux. Oedema was assessed by the wet-to-dry-weight ratio of the EDL. In NS-treated animals closed soft-tissue injury resulted in massive reduction of functional capillary density (FCD) and a marked increase in microvascular permeability and leukocyte-endothelial cell interaction as compared with the control group. By contrast, HS/HES was effective in restoring the FCD to 94% of values found in the control group. In addition, leukocyte rolling decreased almost to control levels and leukocyte adherence was found to be reduced by ~50%. Erythrocyte flux in NS-treated animals decreased to 90 ± 8% (mean . sem. ), whereas values in the HS/HES group significantly increased to 137 ± 3% compared with the baseline flux. Oedema in the HS/HES group (1.06 ± 0.02) was significantly decreased compared with the NS-group (1.12 ± 0.01). HS/HES effectively restores nutritive perfusion, decreases leukocyte adherence, improves endothelial integrity and attenuates oedema, thereby restricting tissue damage evolving secondary to closed soft-tissue injury. It appears to be an effective intervention, supporting nutritional blood flow by reducing trauma-induced microvascular dysfunction

Aims

The purpose of this study was to compare the clinical, radiological, and patient-reported outcome measures (PROMs) in the first 100 consecutive patients undergoing total hip arthroplasty (THA) via a direct superior approach (DSA) with a matched group of patients undergoing THA by the same surgeon, using a posterolateral approach (PLA).

Aims

Osteonecrosis (ON) can cause considerable morbidity in young people who undergo treatment for acute lymphoblastic leukaemia (ALL). The aims of this study were to determine the operations undertaken for ON in this population in the UK, along with the timing of these operations and any sequential procedures that are used in different joints. We also explored the outcomes of those patients treated by core decompression (CD), and compared this with conservative management, in both the pre- or post-collapse stages of ON.

Aims

The aim of this study was to examine whether tourniquet use can improve perioperative blood loss, early function recovery, and pain after primary total knee arthroplasty (TKA) in the setting of multiple-dose intravenous tranexamic acid.

Aims

To assess the impact of the declaration of the state of emergency due to the COVID-19 pandemic on the number of visits to a traumatology emergency department (ED), and on their severity.

Aims

Dual plating of distal femoral fractures with medial and lateral implants has been performed to improve construct mechanics and alignment, in cases where isolated lateral plating would be insufficient. This may potentially compromise vascularity, paradoxically impairing healing. This study investigates effects of single versus dual plating on distal femoral vascularity.

Aims

To evaluate the outcomes of terrible triad injuries (TTIs) in mid-term follow-up and determine whether surgical treatment of the radial head influences clinical and radiological outcomes.

Aims

Computer-based applications are increasingly being used by orthopaedic surgeons in their clinical practice. With the integration of technology in surgery, augmented reality (AR) may become an important tool for surgeons in the future. By superimposing a digital image on a user’s view of the physical world, this technology shows great promise in orthopaedics. The aim of this review is to investigate the current and potential uses of AR in orthopaedics.

Objectives

The use of the haptically bounded saw blades in robotic-assisted total knee arthroplasty (RTKA) can potentially help to limit surrounding soft-tissue injuries. However, there are limited data characterizing these injuries for cruciate-retaining (CR) TKA with the use of this technique. The objective of this cadaver study was to compare the extent of soft-tissue damage sustained through a robotic-assisted, haptically guided TKA (RATKA) versus a manual TKA (MTKA) approach.

Continuous technical improvement in spinal surgical procedures, with the aim of enhancing patient outcomes, can be assisted by the deployment of advanced technologies including navigation, intraoperative CT imaging, and surgical robots. The latest generation of robotic surgical systems allows the simultaneous application of a range of digital features that provide the surgeon with an improved view of the surgical field, often through a narrow portal.

There is emerging evidence that procedure-related complications and intraoperative blood loss can be reduced if the new technologies are used by appropriately trained surgeons. Acceptance of the role of surgical robots has increased in recent years among a number of surgical specialities including general surgery, neurosurgery, and orthopaedic surgeons performing major joint arthroplasty. However, ethical challenges have emerged with the rollout of these innovations, such as ensuring surgeon competence in the use of surgical robotics and avoiding financial conflicts of interest. Therefore, it is essential that trainees aspiring to become spinal surgeons as well as established spinal specialists should develop the necessary skills to use robotic technology safely and effectively and understand the ethical framework within which the technology is introduced.

Traditional and more recently developed platforms exist to aid skill acquisition and surgical training which are described.

The aim of this narrative review is to describe the role of surgical robotics in spinal surgery, describe measures of proficiency, and present the range of training platforms that institutions can use to ensure they employ confident spine surgeons adequately prepared for the era of robotic spinal surgery.

Cite this article: Bone Joint J 2020;102-B(5):568–572.

Aims

The current global pandemic due to COVID-19 is generating significant burden on the health service in the UK. On 23 March 2020, the UK government issued requirements for a national lockdown. The aim of this multicentre study is to gain a greater understanding of the impact lockdown has had on the rates, mechanisms and types of injuries together with their management across a regional trauma service.

Aims

Robotic-assisted total knee arthroplasty (RA-TKA) has been introduced to provide accurate bone cuts and help achieve the target knee alignment, along with symmetric gap balancing. The purpose of this study was to determine if any early clinical benefits could be realized following TKA using robotic-assisted technology.

Aims

The purpose of this study was to evaluate the in vitro effects of apocynin, an inhibitor of nicotinamide adenine dinucleotide phosphate oxidase (NOX) and a downregulator of intracellular reactive oxygen species (ROS), on high glucose-induced oxidative stress on tenocytes.

Aims

The aim of this study was to investigate whether clinical and radiological outcomes after intramedullary nailing of displaced fractures of the fifth metacarpal neck using a single thick Kirschner wire (K-wire) are noninferior to those of technically more demanding fixation with two thinner dual wires.

Objectives

The aim of this study was to investigate the effect of hyperglycaemia on oxidative stress markers and inflammatory and matrix gene expression within tendons of normal and diabetic rats and to give insights into the processes involved in tendinopathy.

Objectives

Previous studies have evidenced cement-in-cement techniques as reliable in revision arthroplasty. Commonly, the original cement mantle is reshaped, aiding accurate placement of the new stem. Ultrasonic devices selectively remove cement, preserve host bone, and have lower cortical perforation rates than other techniques. As far as the authors are aware, the impact of ultrasonic devices on final cement-in-cement bonds has not been investigated. This study assessed the impact of cement removal using the Orthosonics System for Cemented Arthroplasty Revision (OSCAR; Orthosonics) on final cement-in-cement bonds.

Aims

To assess the diagnostic value of C-reactive protein (CRP), leucocyte count (LC), and erythrocyte sedimentation rate (ESR) in late fracture-related infection (FRI).

Objectives

Recently, high failure rates of metal-on-metal (MOM) hip implants have raised concerns of cobalt toxicity. Adverse reactions occur to cobalt nanoparticles (CoNPs) and cobalt ions (Co²⁺) during wear of MOM hip implants, but the toxic mechanism is not clear.

Aims

The aim of this study was to assess the influence of obesity on the clinical outcomes and survivorship ten years postoperatively in patients who underwent a fixed-bearing unicompartmental knee arthroplasty (UKA).

Objectives

Prosthetic joint infection (PJI) is a devastating complication following total joint arthroplasty. Non-contact induction heating of metal implants is a new and emerging treatment for PJI. However, there may be concerns for potential tissue necrosis. It is thought that segmental induction heating can be used to control the thermal dose and to limit collateral thermal injury to the bone and surrounding tissues. The purpose of this study was to determine the thermal dose, for commonly used metal implants in orthopaedic surgery, at various distances from the heating centre (HC).

Aims

The aim of this study was to evaluate the outcomes of a salvage procedure using a 95° angled blade plate for failed osteosynthesis of atypical subtrochanteric femoral fractures associated with the long-term use of bisphosphonates. These were compared with those for failed osteosynthesis of subtrochanteric fractures not associated with bisphosphonate treatment.

Aims

This study investigated the influence of body mass index (BMI) on patients’ function and quality of life ten years after total knee arthroplasty (TKA).

Aims

Identifying predictors of compartment syndrome in the foot after a fracture of the calcaneus may lead to earlier diagnosis and treatment. The aim of our study was to identify any such predictors.

Aims

To present a surgically relevant update of trunnionosis.

Objectives

The diagnosis of periprosthetic joint infection (PJI) is difficult and requires a battery of tests and clinical findings. The purpose of this review is to summarize all current evidence for common and new serum biomarkers utilized in the diagnosis of PJI.

Objectives

This study aimed to investigate the functional effects of microRNA (miR)-214-5p on osteoblastic cells, which might provide a potential role of miR-214-5p in bone fracture healing.

Objectives

The aim of this study was to compare the biomechanical stability and clinical outcome of external fixator combined with limited internal fixation (EFLIF) and open reduction and internal fixation (ORIF) in treating Sanders type 2 calcaneal fractures.

The mucopolysaccharidoses (MPS) are a group of inherited lysosomal storage disorders with clinical manifestations relevant to the orthopaedic surgeon. Our aim was to review the recent advances in their management and the implications for surgical practice.

The current literature about MPSs is summarised, emphasising orthopaedic complications and their management.

Recent advances in the diagnosis and management of MPSs include the recognition of slowly progressive, late presenting subtypes, developments in life-prolonging systemic treatment and potentially new indications for surgical treatment. The outcomes of surgery in these patients are not yet validated and some procedures have a high rate of complications which differ from those in patients who do not have a MPS.

The diagnosis of a MPS should be considered in adolescents or young adults with a previously unrecognised dysplasia of the hip. Surgeons treating patients with a MPS should report their experience and studies should include the assessment of function and quality of life to guide treatment.

Cite this article: Bone Joint J 2017;99-B:1132–9

Objectives

Distraction osteogenesis (DO) mobilises bone regenerative potential and avoids the complications of other treatments such as bone graft. The major disadvantage of DO is the length of time required for bone consolidation. Mesenchymal stem cells (MSCs) have been used to promote bone formation with some good results.

The United States and Canada are in the midst of an epidemic of the use, misuse and overdose of opioids, and deaths related to overdose. This is the direct result of overstatement of the benefits and understatement of the risks of using opioids by advocates and pharmaceutical companies. Massive amounts of prescription opioids entered the community and were often diverted and misused. Most other parts of the world achieve comparable pain relief using fewer opioids.

The misconceptions about opioids that created this epidemic are finding their way around the world. There is particular evidence of the increased prescription of strong opioids in Europe.

Opioids are addictive and dangerous. Evidence is mounting that the best pain relief is obtained through resilience. Opioids are often prescribed when treatments to increase resilience would be more effective.

Cite this article: Bone Joint J 2017;99-B:856–64.

Aims

To determine ten-year failure rates following 36 mm metal-on-metal (MoM) Pinnacle total hip arthroplasty (THA), and identify predictors of failure.

Aims

The aim of the study was to develop a quantitative scoring system to predict whether a large-to-massive rotator cuff tear was arthroscopically reparable prior to surgery.

Objectives

Rotator cuff tears are among the most frequent upper extremity injuries. Current treatment strategies do not address the poor quality of the muscle and tendon following chronic rotator cuff tears. Hypoxia-inducible factor-1 alpha (HIF-1α) is a transcription factor that activates many genes that are important in skeletal muscle regeneration. HIF-1α is inhibited under normal physiological conditions by the HIF prolyl 4-hydroxylases (PHDs). In this study, we used a pharmacological PHD inhibitor, GSK1120360A, to enhance the activity of HIF-1α following the repair of a chronic cuff tear, and measured muscle fibre contractility, fibrosis, gene expression, and enthesis mechanics.

Aims

The aim of this study was to report the outcome following primary fixation or a staged protocol for type C fractures of the tibial plafond.

Objectives

This study aimed to characterise and qualitatively grade the severity of the corrosion particles released into the hip joint following taper corrosion.

Aims

This study investigated the influence of body mass index (BMI) on the post-operative fall in the level of haemoglobin (Hb), length of hospital stay (LOS), 30-day re-admission rate, functional outcome and quality of life, two years after total knee arthroplasty (TKA).

Aims

We examined risk of developing acute renal failure and the associated mortality among patients aged > 65 years undergoing surgery for a fracture of the hip.

Objectives

Hips with metal-on-metal total hip arthroplasty (MoM THA) have a high rate of adverse local tissue reactions (ALTR), often associated with hypersensitivity reactions. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) measures tissue perfusion with the parameter Ktrans (volume transfer constant of contrast agent). Our purpose was 1) to evaluate the feasibility of DCE-MRI in patients with THA and 2) to compare DCE-MRI in patients with MoM bearings with metal-on-polyethylene (MoP) bearings, hypothesising that the perfusion index Ktrans in hips with MoM THA is higher than in hips with MoP THA.

We compared the incidence of pseudotumours after large head metal-on-metal (MoM) total hip arthroplasty (THA) with that after conventional metal-on-polyethylene (MoP) THA and assessed the predisposing factors to pseudotumour formation.

From a previous randomised controlled trial which compared large head (38 mm to 60 mm) cementless MoM THA with conventional head (28 mm) cementless MoP THA, 93 patients (96 THAs: 41 MoM (21 males, 20 females, mean age of 64 years, standard deviation (sd) 4) and 55 MoP (25 males, 30 females, mean age of 65 years, sd 5) were recruited after a mean follow-up of 50 months (36 to 64).

The incidence of pseudotumours, measured using a standardised CT protocol was 22 (53.7%) after MoM THA and 12 (21.8%) after MoP THA. Women with a MoM THA were more likely to develop a pseudotumour than those with a MoP THA (15 vs 7, odds ratio (OR) = 13.4, p < 0.001). There was a similar incidence of pseudotumours in men with MoM THAs and those with MoP THAs (7 vs 5, OR = 2.1, p = 0.30). Elevated cobalt levels (≥ 5 microgram/L) were only associated with pseudotumours in women with a MoM THA. There was no difference in mean Oxford and Harris hip scores between patients with a pseudotumour and those without.

Contrary to popular belief, pseudotumours occur frequently around MoP THAs. Women with a MoM THA and an elevated cobalt level are at greatest risk. In this study, pseudotumours had no effect on the functional outcome after either large head MoM or conventional MoP THA.

Cite this article: Bone Joint J 2015;97-B:1481–7.

The June 2015 Wrist & Hand Roundup360 looks at: Collagenase and Dupuytren’s disease – a genuine alternative to surgery?; iPad PROMise?; Should we learn how to do endoscopic carpal tunnel release?; Two-week radiographs a relic of the past?; Bible? Aspirate or excise?; Patient expectations and trapeziometacarpal osteoarthritis; Splintage in the treatment of sagittal band incompetence and extensor tendon subluxation

This conversation represents an attempt by several arthroplasty surgeons to critique several abstracts presented over the last year as well as to use them as a jumping off point for trying to figure out where they fit in into our current understanding of multiple issues in modern hip and knee arthroplasty.

Aims

The aims of this study were to compare the diagnostic test characteristics of ultrasound alone, metal artefact reduction sequence MRI (MARS-MRI) alone, and ultrasound combined with MARS-MRI for identifying intra-operative pseudotumours in metal-on-metal hip resurfacing (MoMHR) patients undergoing revision surgery.

Periprosthetic joint infection (PJI) is one of the most feared and challenging complications following total knee arthroplasty. We provide a detailed description of our current understanding regarding the management of PJI of the knee, including diagnostic aids, pre-operative planning, surgical treatment, and outcome.

Cite this article: Bone Joint J 2015;97-B(10 Suppl A):20–9.

Only limited data are available regarding the infiltration of local anaesthetic for total hip arthroplasty (THA), and no studies were performed for THA using the anterior approach.

In this prospective, randomised placebo-controlled study we investigated the effect of both standard and reverse infiltration of local anaesthetic in combination with the anterior approach for THA. The primary endpoint was the mean numeric rating score for pain four hours post-operatively. In addition, we recorded the length of hospital stay, the operating time, the destination of the patient at discharge, the use of pain medication, the occurrence of side effects and pain scores at various times post-operatively.

Between November 2012 and January 2014, 75 patients were included in the study. They were randomised into three groups: standard infiltration of local anaesthetic, reversed infiltration of local anaesthetic, and placebo. There was no difference in mean numeric rating score for pain four hours post-operatively (p = 0.87). There were significantly more side effects at one and eight hours post-operatively in the placebo group (p = 0.02; p = 0.03), but this did not influence the mobilisation of the patients. There were no differences in all other outcomes between the groups.

We found no clinically relevant effect when the infiltration of local anaesthetic with ropivacaine and epinephrine was used in a multimodal pain protocol for THA using the anterior approach.

Cite this article: Bone Joint J 2015; 97-B:734–40.

The October 2014 Oncology Roundup³⁶⁰ looks at: how best to reconstruct humeral tumours; not everything is better via the arthroscope; obesity and sarcoma; frozen autograft; en-bloc resection and metastatic disease; positive margins in soft-tissue injuries; lipomatous tumours explored; and what happens with recurrence of osteosarcoma.

Modern principles for the treatment of open fractures include stabilisation of the bone and management of the soft tissues. Wound debridement and irrigation is thought to be the mainstay in reducing the incidence of infection. Although numerous studies on animals and humans have focused on the type of irrigation performed, little is known of the factors which influence irrigation. This paper evaluates the evidence, particularly with regard to additives and the mode of delivery of irrigation fluid.

Normal saline should be used and although many antiseptics and antibiotics have been employed, no consensus has been reached as to the ideal additive. Despite the advocates of high-pressure methods highlighting the improved dilutional ability of such techniques, the results are inconclusive and these irrigation systems are not without complications.

New systems for debridement are currently being investigated, and an ideal method has yet to be determined.

Nanotechnology is the study, production and controlled manipulation of materials with a grain size < 100 nm. At this level, the laws of classical mechanics fall away and those of quantum mechanics take over, resulting in unique behaviour of matter in terms of melting point, conductivity and reactivity. Additionally, and likely more significant, as grain size decreases, the ratio of surface area to volume drastically increases, allowing for greater interaction between implants and the surrounding cellular environment. This favourable increase in surface area plays an important role in mesenchymal cell differentiation and ultimately bone–implant interactions.

Basic science and translational research have revealed important potential applications for nanotechnology in orthopaedic surgery, particularly with regard to improving the interaction between implants and host bone. Nanophase materials more closely match the architecture of native trabecular bone, thereby greatly improving the osseo-integration of orthopaedic implants. Nanophase-coated prostheses can also reduce bacterial adhesion more than conventionally surfaced prostheses. Nanophase selenium has shown great promise when used for tumour reconstructions, as has nanophase silver in the management of traumatic wounds. Nanophase silver may significantly improve healing of peripheral nerve injuries, and nanophase gold has powerful anti-inflammatory effects on tendon inflammation.

Considerable advances must be made in our understanding of the potential health risks of production, implantation and wear patterns of nanophase devices before they are approved for clinical use. Their potential, however, is considerable, and is likely to benefit us all in the future.

Cite this article: Bone Joint J 2014; 96-B: 569–73.

This article presents an overview of mycetoma and offers guidelines for orthopaedic surgeons who may be involved in the care of patients with this condition.

Cite this article: Bone Joint J 2014;96-B:420–5.

Surface hip replacement (SHR) is generally used in younger, active patients as an alternative conventional total hip replacement in part because of the ability to preserve femoral bone. This major benefit of surface replacement will only hold true if revision procedures of SHRs are found to provide good clinical results.

A retrospective review of SHR revisions between 2007 and 2012 was presented, and the type of revision and aetiologies were recorded. There were 55 SHR revisions, of which 27 were in women. At a mean follow-up of 2.3 years (0.72 to 6.4), the mean post-operative Harris hip score (HHS) was 94.8 (66 to 100). Overall 23 were revised for mechanical reasons, nine for impingement, 13 for metallosis, nine for unexplained pain and one for sepsis. Of the type of revision surgery performed, 14 were femoral-only revisions; four were acetabular-only revisions, and 37 were complete revisions.

We did not find that clinical scores were significantly different between gender or different types of revisions. However, the mean post-operative HHS was significantly lower in patients revised for unexplained pain compared with patients revised for mechanical reasons (86.9 (66 to 100) versus 99 (96 to 100); p = 0.029). There were two re-revisions for infection in the entire cohort.

Based on the overall clinical results, we believe that revision of SHR can have good or excellent results and warrants a continued use of the procedure in selected patients. Close monitoring of these patients facilitates early intervention, as we believe that tissue damage may be related to the duration of an ongoing problem. There should be a low threshold to revise a surface replacement if there is component malposition, rising metal ion levels, or evidence of soft-tissue abnormalities.

Cite this article: Bone Joint J 2013;95-B, Supple A:88–91.

We have assessed the different adhesive properties of some of the most common bacteria associated with periprosthetic joint infection on various types of ultra high molecular Weight Polyethylene (UHMWPE). Quantitative in vitro analysis of the adhesion of biofilm producing strains of Staphylococcus aureus and Escherichia coli to physically and chemically characterised standard UHMWPE (PE), vitamin E blended UHMWPE (VE-PE) and oxidised UHMWPE (OX-PE) was performed using a sonication protocol. A significant decreased bacterial adhesion was registered for both strains on VE-PE, in comparison with that observed on PE, within 48 hours of observation (S. aureus p = 0.024 and E. coli p = 0.008). Since Vitamin E reduces bacterial adhesive ability, VE-stabilised UHMWPE could be valuable in joint replacement by presenting excellent mechanical properties, while reducing bacterial adhesiveness.

Cite this article: Bone Joint J 2014;96-B:497–501.

We undertook a retrospective cohort study to determine clinical outcomes following the revision of metal-on-metal (MoM) hip replacements for adverse reaction to metal debris (ARMD), and to identify predictors of time to revision and outcomes following revision. Between 1998 and 2012 a total of 64 MoM hips (mean age at revision of 57.8 years; 46 (72%) female; 46 (72%) hip resurfacings and 18 (28%) total hip replacements) were revised for ARMD at one specialist centre. At a mean follow-up of 4.5 years (1.0 to 14.6) from revision for ARMD there were 13 hips (20.3%) with post-operative complications and eight (12.5%) requiring re-revision.

The Kaplan–Meier five-year survival rate for ARMD revision was 87.9% (95% confidence interval 78.9 to 98.0; 19 hips at risk). Excluding re-revisions, the median absolute Oxford hip score (OHS) following ARMD revision using the percentage method (0% best outcome and 100% worst outcome) was 18.8% (interquartile range (IQR) 7.8% to 48.3%), which is equivalent to 39/48 (IQR 24.8/48 to 44.3/48) when using the modified OHS. Histopathological response did not affect time to revision for ARMD (p = 0.334) or the subsequent risk of re-revision (p = 0.879). Similarly, the presence or absence of a contralateral MoM hip bearing did not affect time to revision for ARMD (p = 0.066) or the subsequent risk of re-revision (p = 0.178).

Patients revised to MoM bearings had higher rates of re-revision (five of 16 MoM hips re-revised; p = 0.046), but those not requiring re-revision had good functional results (median absolute OHS 14.6% or 41.0/48). Short-term morbidity following revision for ARMD was comparable with previous reports. Caution should be exercised when choosing bearing surfaces for ARMD revisions.

Cite this article: Bone Joint J 2014;96-B:1600–9.

Compartment pressures have not previously been studied in healthy children. We compared the pressures in the four lower leg compartments of healthy children with those of healthy adults.

We included patients aged between two months and six years, and measured the pressures in 80 compartments of 20 healthy children using simple needle manometry. Measurements were repeated in a control group of 20 healthy adults.

The mean compartment pressure in the lower leg in children was significantly higher than in adults (p < 0.001). On average, pressures in the four compartments varied between 13.3 mmHg and 16.6 mmHg in the children and between 5.2 mmHg and 9.7 mmHg in the adults. The latter is in accordance with those recorded in the literature. The mean arterial pressure did not relate to age or to pressure in the compartment.

The findings of this study that the normal compartment pressure of the lower leg in healthy children is significantly higher than that in adults may be of considerable significance in clinical decision-making in children of this age.

In this paper, we will consider the current role of simultaneous-bilateral TKA. Based on available evidence, it is our opinion that bilateral one stage TKR is a safe and efficacious treatment for patients with severe bilateral arthritic knee disease but should be reserved for selected patients without significant medical comorbidities.

This study evaluates the long-term survival of spinal implants after surgical site infection (SSI) and the risk factors associated with treatment failure.

A Kaplan-Meier survival analysis was carried out on 43 patients who had undergone a posterior spinal fusion with instrumentation between January 2006 and December 2008, and who consecutively developed an acute deep surgical site infection. All were appropriately treated by surgical debridement with a tailored antibiotic program based on culture results for a minimum of eight weeks.

A ‘terminal event’ or failure of treatment was defined as implant removal or death related to the SSI. The mean follow-up was 26 months (1.03 to 50.9). A total of ten patients (23.3%) had a terminal event. The rate of survival after the first debridement was 90.7% (95% confidence interval (CI) 82.95 to 98.24) at six months, 85.4% (95% CI 74.64 to 96.18) at one year, and 73.2% (95% CI 58.70 to 87.78) at two, three and four years. Four of nine patients required re-instrumentation after implant removal, and two of the four had a recurrent infection at the surgical site. There was one recurrence after implant removal without re-instrumentation.

Multivariate analysis revealed a significant risk of treatment failure in patients who developed sepsis (hazard ratio (HR) 12.5 (95% confidence interval (CI) 2.6 to 59.9); p < 0.001) or who had > three fused segments (HR 4.5 (95% CI 1.25 to 24.05); p = 0.03). Implant survival is seriously compromised even after properly treated surgical site infection, but progressively decreases over the first 24 months.

Cite this article: Bone Joint J 2013;95-B:1121–6.

We suggest that different mechanisms underlie joint pain at rest and on movement in osteoarthritis and that separate assessment of these two features with a visual analogue scale (VAS) offers better information about the likely effect of a total knee replacement (TKR) on pain. The risk of persistent pain after TKR may relate to the degree of central sensitisation before surgery, which might be assessed by determining the pain threshold to an electrical stimulus created by a special tool, the Pain Matcher. Assessments were performed in 69 patients scheduled for TKR. At 18 months after operation, separate assessment of pain at rest and with movement was again carried out using a VAS in order to enable comparison of pre- and post-operative measurements. A less favourable outcome in terms of pain relief was observed for patients with a high pre-operative VAS score for pain at rest and a low pain threshold, both features which may reflect a central sensitisation mechanism.

In this paper, we will consider the current role of metal-on-metal bearings by looking at three subtypes of MoM hip arthroplasty separately: Hip resurfacing, large head (> 36 mm) MoM THA and MoM THA with traditional femoral head sizes.

Bone marrow mesenchymal stromal cells were aspirated from immature male green fluorescent protein transgenic rats and cultured in a monolayer. Four weeks after the creation of the osteochondral defect, the rats were divided into three groups of 18: the control group, treated with an intra-articular injection of phosphate-buffered saline only; the drilling group, treated with an intra-articular injection of phosphate-buffered saline with a bone marrow-stimulating procedure; and the bone marrow mesenchymal stromal cells group, treated with an intra-articular injection of bone marrow mesenchymal stromal cells plus a bone marrow-stimulating procedure. The rats were then killed at 4, 8 and 12 weeks after treatment and examined.

The histological scores were significantly better in the bone marrow mesenchymal stromal cells group than in the control and drilling groups at all time points (p < 0.05). The fluorescence of the green fluorescent protein-positive cells could be observed in specimens four weeks after treatment.

We undertook a retrospective case-control study to assess the clinical variables associated with infections in open fractures. A total of 1492 open fractures were retrieved; these were Gustilo and Anderson grade I in 663 (44.4%), grade II in 370 (24.8%), grade III in 310 (20.8%) and unclassifiable in 149 (10.0%). The median duration of prophylaxis was three days (interquartile range (IQR) 1 to 3), and the median number of surgical interventions was two (1 to 9). We identified 54 infections (3.6%) occurring at a median of ten days (IQR 5 to 20) after trauma. Pathogens intrinsically resistant to the empirical antibiotic regimen used (enterococci, Enterobacter spp, Pseudomonas spp) were documented in 35 of 49 cases (71%). In multivariable regression analyses, grade III fractures and vascular injury or compartment syndrome were significantly associated with infection. Overall, compared with one day of antibiotic treatment, two to three days (odds ratio (OR) 0.6 (95% confidence interval (CI) 0.2 to 2.0)), four to five days (OR 1.2 (95% CI 0.3 to 4.9)), or > five days (OR 1.4 (95% CI 0.4 to 4.4)) did not show any significant differences in the infection risk. These results were similar when multivariable analysis was performed for grade III fractures only (OR 0.3 (95% CI 0.1 to 3.4); OR 0.6 (95% CI 0.2 to 2.1); and OR 1.7 (95% CI 0.5 to 6.2), respectively).

Infection in open fractures is related to the extent of tissue damage but not to the duration of prophylactic antibiotic therapy. Even for grade III fractures, a one-day course of prophylactic antibiotics might be as effective as prolonged prophylaxis.

Cite this article: Bone Joint J 2013;95-B:831–7.

The subject of central nervous system damage includes a wide variety of problems, from the slow selective ‘picking off’ of characteristic sub-populations of neurons typical of neurodegenerative diseases, to the wholesale destruction of areas of brain and spinal cord seen in traumatic injury and stroke. Experimental repair strategies are diverse and the type of pathology dictates which approach will be appropriate. Damage may be to grey matter (loss of neurons), white matter (cutting of axons, leaving neurons otherwise intact, at least initially) or both. This review will consider four possible forms of treatment for repair of the human central nervous system.

The purpose of this study was to determine whether patients with a burst fracture of the thoracolumbar spine treated by short segment pedicle screw fixation fared better clinically and radiologically if the affected segment was fused at the same time. A total of 50 patients were enrolled in a prospective study and assigned to one of two groups. After the exclusion of three patients, there were 23 patients in the fusion group and 24 in the non-fusion group. Follow-up was at a mean of 23.9 months (18 to 30). Functional outcome was evaluated using the Greenough Low Back Outcome Score. Neurological function was graded using the American Spinal Injury Association Impairment Scale. Radiological outcome was assessed on the basis of the angle of kyphosis.

Peri-operative blood transfusion requirements and duration of surgery were significantly higher in the fusion group (p = 0.029 and p < 0.001, respectively). There were no clinical or radiological differences in outcome between the groups (all outcomes p > 0.05). The results of this study suggest that adjunctive fusion is unnecessary when managing patients with a burst fracture of the thoracolumbar spine with short segment pedicle screw fixation.

Objectives

In order to elucidate the influence of sympathetic nerves on lumbar radiculopathy, we investigated whether sympathectomy attenuated pain behaviour and altered the electrical properties of the dorsal root ganglion (DRG) neurons in a rat model of lumbar root constriction.

Plasma levels of cobalt and chromium ions and Metal Artefact Reduction Sequence (MARS)-MRI scans were performed on patients with 209 consecutive, unilateral, symptomatic metal-on-metal (MoM) hip arthroplasties. There was wide variation in plasma cobalt and chromium levels, and MARS-MRI scans were positive for adverse reaction to metal debris (ARMD) in 84 hips (40%). There was a significant difference in the median plasma cobalt and chromium levels between those with positive and negative MARS-MRI scans (p < 0.001). Compared with MARS-MRI as the potential reference standard for the diagnosis of ARMD, the sensitivity of metal ion analysis for cobalt or chromium with a cut-off of > 7 µg/l was 57%. The specificity was 65%, positive predictive value was 52% and the negative predictive value was 69% in symptomatic patients. A lowered threshold of > 3.5 µg/l for cobalt and chromium ion levels improved the sensitivity and negative predictive value to 86% and 74% but at the expense of specificity (27%) and positive predictive value (44%).

Metal ion analysis is not recommended as a sole indirect screening test in the surveillance of symptomatic patients with a MoM arthroplasty. The investigating clinicians should have a low threshold for obtaining cross-sectional imaging in these patients, even in the presence of low plasma metal ion levels.