Aims

Metagenomic next-generation sequencing (mNGS) is useful in the diagnosis of infectious disease. However, while it is highly sensitive at identifying bacteria, it does not provide information on the sensitivity of the organisms to antibiotics. The purpose of this study was to determine whether the results of mNGS can be used to guide optimization of culture methods to improve the sensitivity of culture from intraoperative samples.

Aims

A limited number of investigations with conflicting results have described perivascular lymphocytic infiltration (PVLI) in the setting of total knee arthroplasty (TKA). The purpose of this study was to determine if PVLI found in TKAs at the time of aseptic revision surgery was associated with worse clinical outcomes and survivorship.

Aims

The Mathys Affinis Short is the most frequently used stemless total shoulder prosthesis in the UK. The purpose of this prospective cohort study is to report the survivorship, clinical, and radiological outcomes of the first independent series of the Affinis Short prosthesis.

Aseptic loosening is a major cause of failure of total hip arthroplasty. The adverse tissue response to prosthetic wear particles, with activation of cytokine and prostanoid production, contributes to bone loss around the implants. We have investigated the possibility that inducible nitric oxide synthase (iNOS) and cyclo-oxygenase-2 (COX-2) are expressed in macrophages in the pseudomembrane at the bone-implant interface, thereby contributing to the periprosthetic bone resorption. We also assessed whether peroxynitrite, a nitric oxide (NO)-derived oxidant associated with cellular injury, is generated in the membrane. Enzymatic activity of iNOS was measured using the arginine-citrulline assay technique and prostaglandin E. 2. (PGE. 2. ), as an indicator of COX-2 activity, was measured using an enzyme immunoassay. Cellular immunoreactivity for iNOS, nitrotyrosine (a marker of peroxynitrite-induced cellular injury) and COX-2 was assessed by quantitative peroxidase immunocytochemistry while immunofluorescence methods were used for subsequent co-localisation studies with CD68. +. macrophages. The presence of calcium-independent iNOS activity and PGE. 2. production was confirmed in the homogenized interface membrane. Immunocytochemistry showed that periprosthetic CD68. +. wear-debris-laden macrophages were the most prominent cell type immunoreactive for iNOS, nitrotyrosine and COX-2. Other periprosthetic inflammatory and resident cell types were also found to immunolocalise nitrotyrosine thereby suggesting peroxynitrite-induced protein nitrosylation and cellular damage not only in NO-producing CD68. +. macrophages, but also in their neighbouring cells. These data indicate that both iNOS and COX-2 are expressed by CD68. +. macrophages in the interface membrane and peroxynitrite-induced cellular damage is evident in such tissue. If high-output NO and peroxynitrite generation were to cause macrophage cell death, this would result in the release of phagocytosed wear debris into the extracellular matrix. A detrimental cycle of events would then be established with further phagocytosis by newly-recruited inflammatory cells and subsequent NO, peroxynitrite and prostanoid synthesis. Since both NO and have been implicated in the induction and PGE. 2. maintenance of chronic inflammation with resulting loss of bone, and peroxynitrite in the pathogenesis of disease states, they may be central to the pathogenesis of aseptic loosening

Aims

It has been shown that the preoperative modification of risk factors associated with obesity may reduce complications after total knee arthroplasty (TKA). However, the optimal method of doing so remains unclear. The aim of this study was to investigate whether a preoperative Risk Stratification Tool (RST) devised in our institution could reduce unexpected intensive care unit (ICU) transfers and 90-day emergency department (ED) visits, readmissions, and reoperations after TKA in obese patients.

Antibiotic resistance represents a threat to human health. It has been suggested that by 2050, antibiotic-resistant infections could cause ten million deaths each year. In orthopaedics, many patients undergoing surgery suffer from complications resulting from implant-associated infection. In these circumstances secondary surgery is usually required and chronic and/or relapsing disease may ensue. The development of effective treatments for antibiotic-resistant infections is needed. Recent evidence shows that bacteriophage (phages; viruses that infect bacteria) therapy may represent a viable and successful solution. In this review, a brief description of bone and joint infection and the nature of bacteriophages is presented, as well as a summary of our current knowledge on the use of bacteriophages in the treatment of bacterial infections. We present contemporary published in vitro and in vivo data as well as data from clinical trials, as they relate to bone and joint infections. We discuss the potential use of bacteriophage therapy in orthopaedic infections. This area of research is beginning to reveal successful results, but mostly in nonorthopaedic fields. We believe that bacteriophage therapy has potential therapeutic value for implant-associated infections in orthopaedics.

Cite this article: Bone Joint J 2021;103-B(2):234–244.

Limb alignment in total knee arthroplasty (TKA) influences periarticular soft-tissue tension, biomechanics through knee flexion, and implant survival. Despite this, there is no uniform consensus on the optimal alignment technique for TKA. Neutral mechanical alignment facilitates knee flexion and symmetrical component wear but forces the limb into an unnatural position that alters native knee kinematics through the arc of knee flexion. Kinematic alignment aims to restore native limb alignment, but the safe ranges with this technique remain uncertain and the effects of this alignment technique on component survivorship remain unknown. Anatomical alignment aims to restore predisease limb alignment and knee geometry, but existing studies using this technique are based on cadaveric specimens or clinical trials with limited follow-up times. Functional alignment aims to restore the native plane and obliquity of the joint by manipulating implant positioning while limiting soft tissue releases, but the results of high-quality studies with long-term outcomes are still awaited. The drawbacks of existing studies on alignment include the use of surgical techniques with limited accuracy and reproducibility of achieving the planned alignment, poor correlation of intraoperative data to long-term functional outcomes and implant survivorship, and a paucity of studies on the safe ranges of limb alignment. Further studies on alignment in TKA should use surgical adjuncts (e.g. robotic technology) to help execute the planned alignment with improved accuracy, include intraoperative assessments of knee biomechanics and periarticular soft-tissue tension, and correlate alignment to long-term functional outcomes and survivorship.

Aims

To establish our early clinical results of a new total knee arthroplasty (TKA) tibial component introduced in 2013 and compare it to other designs in use at our hospital during the same period.

Aims

Alternative alignment concepts, including kinematic and restricted kinematic, have been introduced to help improve clinical outcomes following total knee arthroplasty (TKA). The purpose of this study was to evaluate the clinical results, along with patient satisfaction, following TKA using the concept of restricted kinematic alignment.

Direct anterior approaches to the hip have gained popularity as a minimally invasive method when performing primary total hip replacement (THR). A retrospective review of a single institution joint registry was performed in order to compare patient outcomes after THR using the Anterior Supine Intermuscular (ASI) approach versus a more conventional direct lateral approach. An electronic database identified 1511 patients treated with 1690 primary THRs between January 2006 and December 2010. Our results represent a summary of findings from our previously published work. We found that patients that underwent an ASI approach had faster functional recovery and higher Harris hip scores in the early post-operative period when compared with patients who had a direct lateral approach The overall complication rate in our ASI group was relatively low (1.7%) compared with other series using the same approach. The most frequent complication was early periprosthetic femoral fractures (0.9%). The dislocation rate in our series was 0.4% and the prosthetic joint infection rate was 0.1%. We suggest that the ASI approach is acceptable and safe when performing THR and encourages early functional recovery of our patients. Cite this article: Bone Joint J 2014;96- B(11 Suppl A):32–5

Between 1999 and 2005, 10 264 patients who had undergone total hip replacement (THR) for subcapital fracture of the hip were compared with 76 520 in whom THR had been performed for other reasons. All the cases were identified through the Swedish Hip Arthroplasty Register. The THRs performed as primary treatment for fracture were also compared with those done after failure of internal fixation. After seven years the rate of revision was higher in THR after fracture (4.4% vs 2.9%). Dislocation and periprosthetic fracture were the most common causes of revision. The risk was higher in men than in women. The type of femoral component and the surgical approach influenced the risk. After correction for gender, type of component and the surgical approach the revision rates were similar in the primary and secondary fracture THR groups. Total hip replacement is therefore a safe method for both the primary and secondary management of fracture of the hip

Aims

This systematic review asked which patterns of complications are associated with the three reverse total shoulder arthroplasty (RTSA) prosthetic designs, as classified by Routman et al, in patients undergoing RTSA for the management of cuff tear arthropathy, massive cuff tear, osteoarthritis, and rheumatoid arthritis. The three implant design philosophies investigated were medial glenoid/medial humerus (MGMH), medial glenoid/lateral humerus (MGLH), and lateral glenoid/medial humerus (LGMH).

Aims

The purpose of this study was to report bone adaptive changes after anatomical total shoulder arthroplasty (TSA) using a standard-length hydroxyapatite (HA)-coated humeral component, and to report on a computer-based analysis of radiographs to determine changes in peri-implant bone density objectively.

We carried out metal artefact-reduction MRI, three-dimensional CT measurement of the position of the component and inductively-coupled plasma mass spectrometry analysis of cobalt and chromium levels in whole blood on 26 patients with unexplained pain following metal-on-metal resurfacing arthroplasty. MRI showed periprosthetic lesions around 16 hips, with 14 collections of fluid and two soft-tissue masses. The lesions were seen in both men and women and in symptomatic and asymptomatic hips. Using three-dimensional CT, the median inclination of the acetabular component was found to be 55° and its positioning was outside the Lewinnek safe zone in 13 of 16 cases. Using inductively-coupled plasma mass spectrometry, the levels of blood metal ions tended to be higher in painful compared with well-functioning metal-on-metal hips. These three clinically useful investigations can help to determine the cause of failure of the implant, predict the need for future revision and aid the choice of revision prostheses

We hypothesised that the use of tantalum (Ta) acetabular components in revision total hip arthroplasty (THA) was protective against subsequent failure due to infection. We identified 966 patients (421 men, 545 women and 990 hips) who had undergone revision THA between 2000 and 2013. The mean follow up was 40.2 months (3 months to 13.1 years). The mean age of the men and women was 62.3 years (31 to 90) and 65.1 years (25 to 92), respectively. . Titanium (Ti) acetabular components were used in 536 hips while Ta components were used in 454 hips. In total, 73 (7.3%) hips experienced subsequent acetabular failure. The incidence of failure was lower in the Ta group at 4.4% (20/454) compared with 9.9% (53/536) in the Ti group (p < 0.001, odds ratio 2.38; 95% CI 1.37 to 4.27). Among the 144 hips (64 Ta, 80 Ti) for which revision had been performed because of infection, failure due to a subsequent infection was lower in the Ta group at 3.1% (2/64) compared with 17.5% (14/80) for the Ti group (p = 0.006). . Thus, the use of Ta acetabular components during revision THA was associated with a lower incidence of failure from all causes and Ta components were associated with a lower incidence of subsequent infection when used in patients with periprosthetic joint infection. . Cite this article: Bone Joint J 2015;97-B:45–9

The cortical strains on the femoral neck and proximal femur were measured before and after implantation of a resurfacing femoral component in 13 femurs from human cadavers. These were loaded into a hip simulator for single-leg stance and stair-climbing. After resurfacing, the mean tensile strain increased by 15% (95% confidence interval (CI) 6 to 24, p = 0.003) on the lateral femoral neck and the mean compressive strain increased by 11% (95% CI 5 to 17, p = 0.002) on the medial femoral neck during stimulation of single-leg stance. On the proximal femur the deformation pattern remained similar to that of the unoperated femurs. The small increase of strains in the neck area alone would probably not be sufficient to cause fracture of the neck However, with patient-related and surgical factors these strain changes may contribute to the risk of early periprosthetic fracture

Aims

The impact of tobacco use on readmission and medical and surgical complications has been documented in hip and knee arthroplasty. However, there remains little information about the effect of smoking on the outcome after total shoulder arthroplasty (TSA). We hypothesized that active smokers are at an increased risk of poor medical and surgial outcomes after TSA.

Aims

The principle strategies of fracture-related infection (FRI) treatment are debridement, antimicrobial therapy, and implant retention (DAIR) or debridement, antimicrobial therapy, and implant removal/exchange. Increasing the period between fracture fixation and FRI revision surgery is believed to be associated with higher failure rates after DAIR. However, a clear time-related cut-off has never been scientifically defined. This systematic review analyzed the influence of the interval between fracture fixation and FRI revision surgery on success rates after DAIR.