16 to 34% of the population suffer from shoulder pain, the most common cause being rotator cuff tears. NICE guidance recommends using ultrasound scan (USS) or MRI to assess these patients, but does not specify which is preferable. This study assesses the accuracy of USS and MRI in rotator cuff tears in a DGH, to establish the most appropriate imaging modality. Patients who had at least two of shoulder ultrasound, MRI or arthroscopy within a seven month period (n=55) were included in this retrospective study. Sensitivity, Specificity, Positive Predictive Value (PPV) and Negative Predictive Value (NPV) were calculated using arthroscopy as the true result, and kappa coefficients calculated for each pairing. 59 comparisons were made in total. Sensitivity for MRI in full supraspinatus tears was 0.83, and for USS 0.75. Specificity for MRI in these tears was 0.75, and for USS 0.83. Values were much lower in other tears, which occurred less frequently. USS and MRI completely agreed with each other 61.3% of the time. Both modalities were only completely accurate 50% of the time. Kappa coefficient between arthroscopy and MRI for supraspinatus tears was 0.658, and for USS was 0.615. There was no statistical difference between MRI and USS sensitivity or specificity (p=1), suggesting that one modality cannot be recommended over the other for full supraspinatus tears. They also do not tend to corroborate one another, suggesting that there is no benefit from doing both scans. Further research is needed to see how both modalities can be improved to increase their accuracy

FAI has been implicated in the progression of osteoarthritis (OA) and early detection may allow for treatment, which can slow or halt progression. FAI is a difficult condition to image and there is little objective evidence about imaging accuracy. We aim to measure the accuracy of five imaging modalities. Three blinded observers retrospectively reviewed five different modalities from two age and sex matched groups: A patient group referred to the outpatient clinic with a clinical diagnosis of FAI and a control group who had had CT scans of the pelvis for suspected trauma, where the Pelvic scan had been reported as showing no injuries. The imaging modalities were: Standard x-ray; Antero-Posterior, Lateral; Condition-specific x-ray projections; Dunn view, lateral internal rotation; Standard Computer Tomography (CT) multiplanar reconstruction (MPR); axial, sagittal and coronal; Condition-specific CT MPR; angled axial, angled coronal; 3D modelling; and surface rendered dynamic. We found marked variations in the sensitivity, specificity, Positive Predictive Value (PPV) and Negative Predictiive Value (NPV) for each of the following imaging modalities: Standard X-ray; Sensitivity 51.9; Specificity; 57.1; PPV; 40; NPV; 68.3 Special X-rays; Sensitivity; 66.7; Specificity; 57.1; PPV; 46.1; NPV; 75.7. Standard CT MPR; Sensitivity; 40.7; Specificity; 75.5; PPV; 47.8; NPV; 69.8 Special CT MPR; Sensitivity; 48.1; Specificity; 57.1; PPV; 46.4; NPV; 70.8 Dynamic 3D CT models; Sensitivity; 55.6; Specificity; 69.3; PPV; 42.8; and NPV; 71.8. The Dynamic 3D CT models (where the observer can manipulate the model in real time three dimension to control the perspective) proved to be the most accurate, closely followed by the special X-Ray views, which were also the most sensitive. The Standard CT MPRs were the most specific but had a low sensitivity. This is the first study to measure sensitivity, specificity and PPV and NPV for these imaging modalities in FAI. We recommend the use of condition-specific X-Ray views as well as 3D CT Models for optimal imaging accuracy in this condition. Standard X-Ray views and CTs proved less useful

ARMD (Adverse Reaction to Metal Debris) is an increasingly recognised complication of metal on metal hip replacements. The MHRA (Medical and Healthcare Related Devices Agency) have advised a blood cobalt or chromium level above 7 mg/L is a threshold for further investigation, stating that “low levels are reassuring and strongly predict not having an adverse outcome”. Cross-sectional imaging should be performed when levels are above 7 mg/L. We have performed a study investigating the specificity and sensitivity of chromium and cobalt metal ion levels as a screening measure for ARMD.

79 ASR hip replacements were performed at our hospital and 75 (95%) of these underwent a Metal Artefact Reduction Sequence (MARS) MRI scan. All patients (64 hips) who had not undergone revision were invited to take part in this study. 57 patients with 62 hip replacements completed hip and activity scores, had blood cobalt and chromium ion level measurements and 3D-CT to measure acetabular component position.

Acetabular component inclination (>50 degrees), small head size (< 51mm) and female gender were significantly correlated with raised chromium (Cr) and cobalt (Co) ion levels. An ARMD was detected using MRI in 18 (29%) of the hips in this study. The incidence of ARMD was significantly higher when chromium concentration was above 7 mg/l (p = 0.02). Chromium ion levels >7 mg/L had a sensitivity of 56% and specificity of 83% for ARMD, and cobalt ion levels >7 mg/L 56% and 76% respectively. 40 patients had cobalt levels <7 mg/L and 33 had chromium levels <7 mg/L, but 8 of these had an ARMD on MRI. All 8 patients had minimal symptoms (Oxford Hip Score ≥ 44 out of 48).

The Medicines and Healthcare Products Regulatory Agency (MHRA) has recommended that cobalt and chromium levels be measured in patients with a metal-on-metal hip replacement and cross-sectional imaging performed when these levels are above 7 μg/L. This study has shown that by using this threshold, in patients with this implant combination, the sensitivity and specificity for the detection of ARMD is low and patients with soft tissue disease may be missed. Furthermore the presence of MRI detected ARMD, in the absence of significant clinical symptoms and with metal ion levels <7 μg/L is of concern.

MoM implants at risk of failure are associated with raised cobalt and chromium levels. However metal ion analysis alone is not reliable as a screening tool for ARMD, which is often clinically “silent”. We recommend the routine use of MARS MRI as the safest method of ARMD diagnosis in patients with MoM implants.

Aims

The risk to patients and healthcare workers of resuming elective orthopaedic surgery following the peak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been difficult to quantify. This has prompted governing bodies to adopt a cautious approach that may be impractical and financially unsustainable. The lack of evidence has made it impossible for surgeons to give patients an informed perspective of the consequences of elective surgery in the presence of SARS-CoV-2. This study aims to determine, for the UK population, the probability of a patient being admitted with an undetected SARS-CoV-2 infection and their resulting risk of death; taking into consideration the current disease prevalence, reverse transcription-polymerase chain reaction (RT-PCR) testing, and preassessment pathway.

Aim. The clinical relevance of microbial DNA detected via next-generation sequencing (NGS) remains unknown. This multicenter study was conceived to: 1) identify species on NGS that may predict periprosthetic joint infection (PJI), then 2) build a predictive model for PJI in a developmental cohort, and 3) validate predictive utility of the model in a separate multi-institutional cohort. Method. Fifteen institutions prospectively collected samples from 194 revision TKA and 184 revision THA between 2017–2019. Synovial fluid, tissue and swabs were obtained intraoperatively and sent to MicrogenDx (Lubbock, TX) for NGS analysis. Reimplantations were excluded. Patients were classified per the 2018 ICM definition of PJI. DNA analysis of community similarities (ANCOM) was used to identify 17 bacterial species of 294 (W-value>50) for differentiating infected vs. noninfected cases. Logistic regression with LASSO selection and random-forest algorithms were then used to build a model for predicting PJI. ICM classification was the response variable (gold-standard) and species identified through ANCOM were predictors. Patients were randomly allocated 1:1 into training and validation sets. Using the training set, a model for PJI diagnosis was generated. The entire model-building procedure and validation was iterated 1000 times. Results. The model's assignment accuracy was 75.9%. There was high accuracy in true-negative and false-negative classification using this model, which has previously been a criticism of NGS. Specificity was 97.1%, PPV 75.0% and NPV 76.2%. On comparison of abundance between ICM-positive and ICM-negative patients, Staphylococcus aureus was the strongest contributor (F=0.99) to model predictive power. In contrast, Cutibacterium acnes was less predictive (F=0.309) and abundant across infected and noninfected revisions. Discussion. This is the first study to utilize predictive algorithms on a large multicenter dataset to transform analytic NGS data into a clinically relevant diagnostic model. Our collaborative findings suggest NGS may be an independent adjunct for PJI diagnosis, while also facilitating pathogen identification. Future work applying machine-learning will improve accuracy and utility of NGS

Aim. Synovial fluid investigation is the best alternative to diagnose prosthetic joint infection (PJI) before adequate microbiological/histology sampling during revision surgery. Although accurate preoperative diagnosis is certainly recommended, puncturing every patient before revision arthroplasty raises concerns about safety and feasibility issues especially in difficult to access joint (e.g., hip), that often require OR time and fluoroscopy/ultrasound guidance. Currently there is no clear guidelines regarding optimal indications to perform preoperative joint aspiration to diagnose PJI before revision surgery. The main goal of this study is to determine the accuracy of our institutional criteria using the new European Bone and Joint Infection Society (EBJIS) PJI definition. Method. We retrospectively evaluated every single- or first-stage for presumed aseptic or known infected revision total hip/knee arthroplasty procedures between 2013–2020. Preoperative clinical and laboratory features were systematically scrutinized. Cases with insufficient information for accurate final PJI diagnosis (i.e., no perioperative synovial fluid examination or no multiple cultures including sonication of removed implant) were excluded. Preoperative joint aspiration is recommended in our institution if any of the following criteria are met: 1) elevated CRP and/or ESR; 2) early failure (<2 years) or repeat failure; 3) high clinical suspicion/risk factors are present. Performance of such criteria were compared against final postoperative EBJIS definition PJI diagnosis. Results. A total of 364 revision THAs or TKAs were performed during the study period. After excluding 258 cases with insufficient information, a total of 106 patients were ultimately included. 38 (35,8 %) were classified as confirmed infections, 10 (9.4 %) as likely infected and 58 (54.7%) as infection unlikely. Of those, 37 confirmed infection cases, 9 likely infected cases and 32 infection unlikely cases did have indication for preoperative synovial fluid collection before revision surgery. Institutional criteria showed 95.8 % Sensitivity, 44.83 % Specificity, 92.9 % Negative Predictive Value (NPV) and 59 % Positive Predictive Value (PPV). Conclusions. Sensitivity and NPV of the aforementioned institutional criteria are very high even with the use of the more sensitive EBJIS PJI definition. As such they seem to be a valid alternative in selecting patients that should be punctured before revision arthroplasty. They identify the vast majority of infected patients while saving a significant number of patients from unnecessary procedures

Aim. Metagenomic nanopore sequencing is demonstrating potential as a tool for diagnosis of infections directly from clinical samples. We have previously shown nanopore sequencing can be used to determine the causative bacterial species in prosthetic joint infections (PJI). However, to make predictions regarding antimicrobial resistance, human DNA contamination must be reduced so a greater proportion of sequence data corresponds to the microbial portion of the DNA extract. Here, we utilise selective DNA extraction from sonication fluid samples to begin to make predictions regarding antimicrobial resistance in PJI. Method. We investigated host cell DNA depletion with 5% saponin selective human cell lysis followed by nuclease digestion. Subsequently, bacterial cells were mechanically lysed before DNA extraction. Sequencing libraries from samples treated with and without saponin were prepared with a Rapid PCR Barcoding Kit. 1. and sequenced in multiplexes of 2–8 samples/flowcell on a GridION. Sequencing reads were analysed using the CRuMPIT pipeline and thresholds to indicate presence of a specific bacterial genus/species were investigated. Antimicrobial resistance determinants were detected using previously published sequences specifically for Staphylococcus aureus, as an example organism frequently causing PJI. Results. 247 DNA extracts from 115 sonication fluids plus controls were subjected to metagenomic sequencing, comprising extracts from 67 culture-positive (10 of which were culture-positive at <50 CFU/ml) and 48 culture-negative samples. 5% saponin depleted human DNA contamination, reducing the number of human sequenced bases to a median 12% from 98% in comparison to 5μm filtration without saponin. In 11 samples 5% saponin depleted human bases by <12% in comparison to 5μm filtration, which may be indicative of incomplete depletion. Bacteria observed in sonication fluid culture were identified to species-level in 49/65 (75%) cases, and to genus-level in 51/65 (78%). Specificity of sequencing was 103/114 (90%). Sequencing made a completely successful prediction of antimicrobial susceptibility in 8/19 S. aureus culture-positive samples treated with 5% saponin, and a partial prediction in 5/19 for the 8 antibiotics investigated. Without 5% saponin treatment sequencing could only detect a limited number of AMR determinants in 3/19 samples. Sequencing correctly predicted 13/15 (87%) resistant and 74/74 (100%) susceptible phenotypes where sufficient sequence data were available. Conclusions. Nanopore metagenomic sequencing can provide species identification in PJI. Additionally, depletion of human DNA improves depth of coverage and allows detection of antimicrobial resistance determinants, demonstrating as a proof of principle that nanopore sequencing could potentially provide a complete diagnostic tool in PJI. 1. Oxford Nanopore Technologies

Various injury severity scores exist for trauma; it is known that they do not correlate accurately to military injuries. A promising anatomical scoring system for blast pelvic and perineal injury led to the development of an improved scoring system using machine-learning techniques. An unbiased genetic algorithm selected optimal anatomical and physiological parameters from 118 military cases. A Naïve Bayesian (NB) model was built using the proposed parameters to predict the probability of survival. Ten-fold cross validation was employed to evaluate its performance. Our model significantly out-performed Injury Severity Score (ISS), Trauma ISS, New ISS and the Revised Trauma Score in virtually all areas; Positive Predictive Value 0.8941, Specificity 0.9027, Accuracy 0.9056 and Area Under Curve 0.9059. A two-sample t-test showed that the predictive performance of the proposed scoring system was significantly better than the other systems (p<0.001). With limited resources and the simplest of Bayesian methodologies we have demonstrated that the Naïve Bayesian model performed significantly better in virtually all areas assessed by current scoring systems used for trauma. This is encouraging and highlights that more can be done to improve trauma systems not only for the military, but also in civilian trauma

Aim. The aim of the study was to assess the accuracy of the alpha defensin lateral flow test for diagnosis of periprosthetic joint infection (PJI) using an optimized diagnostic algorithm and three classification systems. In addition, we compared the performance with synovial fluid leukocyte count, the most sensitive preoperative test. Method. In this prospective multicenter study we included all consecutive patients with painful prosthetic hip and knee joints undergoing diagnostic joint aspiration. Alpha defensin lateral flow test was used according to manufacturer instructions. The following diagnostic criteria were used to confirm infection: Musculoskeletal Infection Society (MSIS), Infectious Diseases Society of America (IDSA) and Swiss orthopedics and Swiss Society of Infectious Diseases (SOSSID). In the latter, PJI was confirmed when at least one of following criteria applied: macroscopic purulence, sinus tract, positive cytology of joint aspirate (>2000 leukocytes/μl or >70% granulocytes), histological proof of acute inflammation in periprosthetic tissue, positive culture (from aspirate, tissue or sonication fluid). Infection was classified as chronic, if symptom duration was more than 3 weeks or if infection manifested after more than 1 month after surgery. The sensitivity and specificity of the alpha defensin lateral flow test and leukocyte count in synovial fluid were calculated and compared using McNemar Chi-square test. Results. Of 151 included patients evaluated for painful prosthetic joints (103 involved knees, 48 hips), the median patient age was 69 years (range, 41–94 years) and 75 patients were female. Systematically evaluating the included patients according to the different diagnostic criteria, MSIS and IDSA revealed both 33 patients with PJI (22%), whereas SOSSID disclosed 47 septic failures (31%), among them 36 chronic infections (77%). Sensitivity of the test was 79% when applying MSIS criteria, 70% with IDSA criteria and 57% with SOSSID criteria. Specificity ranged from 96% (IDSA) to 98% (MSIS) and 99% (SOSSID). Applying the most stringent definition criteria (SOSSID), leukocyte count showed significantly higher sensitivity than the alpha defensin lateral flow test (91% vs. 57%, p<0.001), especially in chronic infections (88% vs. 48%, p<0.001.) In acute infections, both tests detected all infection cases. Processing turnaround time was shorter in Alpha defensin lateral flow test than automated leukocyte count (10 min vs. 2–4 hours). Conclusions. Semi-quantitative alpha defensin test was rapid and highly specific for diagnosing PJI (> 95%). However, sensitivity was limited, especially when applying definition criteria including also low grade infections (SOSSID criteria). Therefore, the alpha defensin lateral flow test does not allow a reliable exclusion of PJI, especially not in chronic infections but may be used as confirmatory test

Tc 99m labelled leukocytes scintigraphy (LLS) could be useful for the diagnosis of bone and joint infections. The aim of our study was to evaluate its performances specifically in the diagnosis of prosthetic joint infection (PJI). We conducted a multicenter -7 year- retrospective study including 164 patients with suspected PJI who underwent surgical treatment. In each case, 5 intraoperative samples were taken. Diagnosis of infection was confirmed if two or more samples yielded the same microbial agent. LLS was considered as « positive » if an accumulation of leukocytes was observed in early stage and increased in late stage (24 hours). Among these patients, 123 had also a bone scintigraphy. A total of 168 PJ were analyzed: 150 by in vitro polymorphonuclear labelled leukocytes scintigraphy (PLLS) and 18 by anti-granulocytes antibodies labelled leukocytes scintigraphy (LeukoScan®). Location of PJ were: hip (n = 63), knee (n = 71), miscellaneous (n = 4). According to microbiological criteria 62 hip prosthesis and 48 knee prosthesis were considered as infected. Sensitivity (Se), Specificity (Sp), Positive Predictive Value (PPV) and Negative Predictive Value of PLLS were: 72%, 60%, 80% and 47%. Se of LLS was higher for knee PJI (87%) than for hip PJI (57%) [p = 0.002]. Although Sp was higher for hip PJI (75%) than for knee PJI (52%) [p = 0.002]. The lowest Se was found for coagulase negative staphylococci (70%) and the highest for streptococci (87.5%). However the difference of Se between bacteria was not significant. Regarding bone scintigraphy, Se, Sp, PPV and NPV were: 94%, 11%, 65% and 50%. In our study, performances of LLS were rather low and varied according to the location of infection. Differences of LLS Se between bacteria was not significant. Bone scintigraphy has a high Se but lacks Sp

The purpose of this study was to investigate the usefulness of PET-CT in the diagnosis and treatment of long bone infections following trauma. All patients referred to the limb reconstruction service for management of non-unions were treated by the same protocol. PET-CT with FDG was performed in all patients to assess if the non-union site was infected and if so, the extent of the infection. Those requiring operative management were treated in a 2-stage manner. Initially with debridement based on PET-CT; sampling for microbiology and histology; and then Teicoplanin and Ciprofloxacin. If samples were positive then the patients were treated for a total of 6 weeks with antibiotics based on microbiology advice before undergoing definitive fixation. The sensitivity, specificity, PPV, and NPV were then calculated for PET-CTs ability to predict presence of infection using extended cultures and histology as the gold standard. 38 consecutive patients underwent surgery, 24 male and 14 female. 24 were deemed infected on extended culture or histology. PET-CT was anecdotally found to be extremely useful at determining the extent of infection to plan debridement. PPV 0.83. NPV 0.89. Sensitivity 0.96. Specificity 0.61. As well as providing unique ability to demarcate areas of bony infection in the presence of metalwork, the ability to detect or exclude infection was exceptional. This is a test, however, which is operator dependent and requires a skilled Nuclear Radiology Consultant to accurately interpret images. In our relatively small pilot study the accuracy improved noticeably over one year. PET-CT has potential to be a powerful tool in the diagnosis and treatment of long bone infection following trauma and certainly warrants further investigation

Magnetic resonance imaging (MRI) scans are widely used in the assessment of knees, often prior to arthroscopic procedures. The reporting of chondral damage on MRI scans can be variable. The correlation between MRI reports of chondral damage and that found at arthroscopy is often inconsistent. The aim of this study was to identify how well MRI reports correlated with the extent of chondral damage found at arthroscopy. A retrospective case-note review of a single-surgeon series of 175 arthroscopic procedures was performed. 83 patients were included in the study. The remainder were excluded if an MRI scan had not been performed, or had been performed more than 3 months prior to surgery. The condition of the articular cartilage demonstrated by MRI was compared to that found at arthroscopy. Data was analysed for presence and extent of chondral damage. Comparison between MRI and arthroscopy findings showed high Specificity (90%) and Negative Predictive Values (89%) for chondral damage, but low Sensitivity (46%). Cohen's kappa values < 0.2 revealed very poor correlation for the extent of damage. This study demonstrates that MRI is good at describing whether articular damage is present but does not reliably describe the extent of the damage

Culture examination is still considered the gold standard for diagnosis of bone and joint infections, including prosthetic ones, even if in up to 20–30% of cases, particularly prosthetic joint infections, it fails to yield microbial growth. To overcome this limitation, determination of markers of inflammation and or infection directly in joint fluid has been proposed. Aim of this study was to evaluate the applicability of measurement of lecukocyte esterase (LE), C-reactive protein (CRP) and glucose in synovial fluid for diagnosis of bone and joint infections. Synovial fluids from 80 patients were aseptically collected and sent to laboratory for microbiological cultures. After centrifugation at 3000 rpm for 10 minutes, pellet was used for cultures, while the surnatant was used for determination of LE, CRP and glucose. LE and glucose were evaluated by means of enzymatic colorimetric strips developed for urinanalysis. One drop of synovial fluid was placed on the LE and on the glucose pads and the results were read after about 120 seconds. A LE test graded + or ++, and a glucose test equal to trace or negative were considered suggestive for infection. CRP was measured by an automated turbidimetric method. On the basis of clinical findings, microbiological, haematological and histological analyses patients were retrospectively divided into 2 groups. Group 1 comprised 19 infected patients (12 males, 7 females age: 70.6 ± 10.3 yrs, range: 47 – 88 yrs) while Group 2 included 61 aseptic patients (32 males and 29 females, age: 61.5 ± 16.3 yrs, range: 15 – 84). Sensitivity of the three tests was 89.5%. 84% and 73,7% for LE, CRP and glucose, respectively. Specificity was 98.4%, 88.5% and 70% for LE, CRP and glucose, respectively. Positive and negative predictive values were 94.4% and 96.8% for LE, 69.6% and 94.6% for CRP and 77.8% and 89.6% for glucose test. When LE was combined with CRP, sensitivity increased to 94.7%, while no differences were observed for LE combined with glucose. Leukocyte esterase has proven to be a rapid, simple and inexpensive test to rule in or out bone and joint infections. Combination of its measurement with that of CRP increased sensitivity. In conclusion, the combination of leukocyte esterase and CRP may represent a simple and useful tool for diagnosis of bone and joint infections

Background. Gram stain microscopy is a routinely requested investigation in the evaluation of septic arthritis in both paediatric and adult patients. Recent evidence suggests that gram stain microscopy has poor diagnostic accuracy in adults with a sensitivity of only 45%, however the diagnostic accuracy remains unknown in children. We sought to establish the diagnostic utility of gram stain microscopy in the diagnosis of septic arthritis in children. Methods. We conducted a retrospective review of all patients of 16 years and under that underwent aspiration and washout of suspected septic joints in theatre from March 2005 to February 2011. Theatre data were cross referenced with microbiology results and analysed by simple descriptive methods in Excel. Results. We identified 23 paediatric patients undergoing washout or aspiration of a suspected septic joint during the time period studied. 17 (74%) of the patients were female and the average age was 2 years (Range 1 month–16 years). The most commonly affected joints were Knees (12/23, 52%) and Hips (7/23, 30%), with the remainder of infections occurring sporadically. There were 9 cases of culture confirmed septic arthritis (39% of all washouts), and these occurred in 5 knees (56%), 3 Hips (33%) and 1 ankle (11%). Organisms were Staphylococcus Aureus (2/8), Coagulase Negative Staphylococcus (2/9), Streptococcus pneumoniae (2/9), Group B Streptococcus (2/9) and Group A Streptococcus (1/9). Gram stain microscopy identified organisms in 3 aspirates both of which were confirmed on extended culture (Sensitivity 33%, Specificity 100%). Conclusion. Gram stain microscopy identified only 33% of culture positive cases of septic arthritis within this study. Our results suggest that gram stain microscopy lacks the diagnostic accuracy to be used in the exclusion of septic arthritis in the paediatric population

Background. In suspected scaphoid fracture the initial scaphoid series plain radiographs are 84-94% sensitive for scaphoid fractures. Patients are immobilised awaiting diagnosis. Unnecessary lengthy immobilisation leads to lost productivity and may leave the wrist stiff. Early accurate diagnosis would improve patient management. Although Magnetic Resonance Imaging (MRI) has come to be regarded as the gold standard in identifying occult scaphoid injury, recent evidence suggests Computer Tomography (CT) to be more accurate in identifying scaphoid cortical fracture. Additionally CT and USS are frequently a more available resource than MRI. We hypothesised that 16 slice CT is superior to high spatial resolution Ultrasonography (USS) in the diagnosis of radiograph negative suspected cortical scaphoid fracture and that a 5 point clinical examination will help to identify patients most likely to have sustained a fracture within this group. Methods. 100 patients with two negative scaphoid series and at least two out of five established clinical signs of scaphoid injury (anatomical snuffbox tenderness (AST), scaphoid tubercle tenderness (STT), effusion, pain on circumduction and pain on axial loading) were prospectively investigated with CT and USS. MRI was arranged for patient with persistent symptoms but negative CT/USS. Results. CT demonstrated 8 scaphoid fractures. 17 other fractures (1st metacarpal, trapezium, trapezoid, distal radius, hook of hammate and triquetral) were also found. USS diagnosed 2/8 scaphoid fractures, raised suspicion in 5/8 and completely missed 1/8. Combining AST, STT with pain on circumduction improved accuracy (sensitivity 87.5% and Specificity 36%). No further fractures were identified on MRI. Conclusions. - CT remains superior to USS for the exclusion of cortical scaphoid fracture. There remains a role for USS if resources are limited. - Combining signs of ASB and tubercle tenderness with pain on circumduction assists in the identification of a ‘fracture likely’ subgroup

Introduction. The wrist arthroscopy has been performed since 1979. With the advances in technology and surgical expertise, wrist arthroscopy has become third commonest procedure after knee and shoulder joint. Wrist arthroscopy has become a gold standard for diagnosing TFCC pathologies and other intercarpal disorders. Our aim was to compare the clinical, MRI and arthroscopic findings while treating various wrist pathologies. Materials/Method. In retrospective trial, 30 patients (19 male and 11 female) with clinical evidence of wrist lesions were evaluated with MRI followed by wrist arthroscopy. The mean age of the patients at the time of outpatient appointment was 44 years with an average waiting time of 6.6 months. Inclusion criteria: all patients undergoing wrist surgery. Exclusion criteria: septic arthritis, acute distal radius fractures. Kappa analysis was used to compare the three methods of wrist pathology assessment. The total 30 patients were assessed for clinical findings, MRI report and corresponding arthroscopic findings. Results. According to the clinical findings, 22 patients (68% of all patients) were diagnosed with suspected TFCC injury. In 21 patients, the MRI showed TFCC tear (partial to complete) and this was confirmed by arthroscopy in 22 patients. There was a correlation of clinical, MRI and arthroscopy in detecting TFCC lesions in 95% cases. Sensitivity 93%, specificity 90%, positive predictive value 89% and negative predictive value 94%. The Scapho-lunate ligament tear was suspected in 8 (28% of all patients). In 6 patients, MRI showed scapho-lunate tear and this was confirmed by wrist arthroscopy in 10 patients. Correlation with wrist arthroscopy was 80%, sensitivity 94%, specificity 92%, positive predictive value 90% and negative predictive value 93%. 15 patients (50% of all patients) showed signs of moderate to severe cartilage wear and 12 patients had confirmation with MRI. Correlation with wrist arthroscopy was 75%, Sensitivity 90%, Specificity 91%, positive predictive value 89% with negative predictive value 92%. However clinical examination and MRI had poor correlation with wrist arthroscopy in diagnosing synovitis. Discussion. The MRI and wrist arthroscopy has fair correlation, though MRI sensitivity approaches that of arthroscopy, it cannot replace it at the moment. However, it is a potent additional tool for wrist diagnosis if intra-articular contrast is used. It can facilitate diagnosis and indications for surgery of the wrist. It may make arthroscopic and more invasive interventions for diagnostic purposes avoidable in future. Our results showed clinical examination is crucial for diagnosing wrist pathologies, MRI can be used as an adjunct but the wrist arthroscopy still remains the gold standard tool for diagnosis and therapeutic interventions

Introduction:. Wear particles cause aseptic loosening by stimulating macrophages to produce inflammatory cytokines. Recent studies indicate that Toll-like receptor 2 (TLR2) and TLR4 mediate macrophage responses to the wear particles [1–3]. TLR2 and TLR4 uniquely activate MyD88-dependent signaling via an additional adapter protein known as TIRAP/Mal [4]. Del Vescovo et al reported that three single nucleotide polymorphisms (SNPs) within the TIRAP/Mal gene associate with aseptic loosening in THA patients [5]. The goal of the current study was therefore to determine whether TIRAP/Mal mediates responses to orthopaedic wear particles. Methods:. Immortalized wild type (WT) and TIRAP/Mal knockout (KO) murine macrophages (Mfs) were incubated in the presence or absence of titanium (Ti) particles (1 × 10. 8. particles/cm. 2. [2]. Three types of particles were used as described previously [1,2]: Ti particles with adherent bacterial debris (38.3 Endotoxin Units/10. 9. particles), endotoxin-free Ti particles (<0.1 EU/10. 9. particles), and Ti particles with adherent lipopolysacharide (LPS, 32.8 EU/10. 9. particles). TNFa, IL-1b, and IL-6 mRNAs were measured by real-time PCR and the secreted cytokines were measured by ELISA. Particle-induced osteolysis in calvaria of TIRAP/Mal KO and WT mice was measured 7 days after particle implantation [1,2]. In vitro results are presented as mean ± SEM of 3–4 replicate experiments analyzed by two-way ANOVA with Bonferroni post-hoc corrections. In vivo results are presented as means of individual parietal bones ± SEM (n = 22) and analyzed by one-way ANOVA on ranks with Student Neuman-Keuls post-hoc corrections. * denotes p < 0.5, ** denotes p < 0.01, *** denotes p < 0. Results:. Ti particles with adherent bacterial debris induced substantial osteolysis and expression of TNFa, IL-1b, and IL-6 at both the mRNA and protein levels and all of those responses were significantly inhibited by TIRAP/Mal KO (Fig 1 & Fig 2). Endotoxin-free Ti particles had a small effect on osteolysis and cytokine mRNA expression that was not dependent on TIRAP/Mal (Fig 1 & data not shown). Adherence of highly purified LPS to the endotoxin-free particles reconstituted the stimulation of osteolysis and cytokine expression as well as the dependence on TIRAP/MAL (Fig 1 & data not shown). Specificity of the effects of TIRAP/Mal KO was demonstrated since responses induced by recombinant murine IL-1b were unaffected (data not shown). Discussion:. Our results are the first demonstration that TIRAP/Mal mediates effects of orthopaedic wear particles. TIRAP/Mal KO inhibited expression of TNFa by ∼50% and almost completely inhibited particle-induced osteolysis, as well as expression of IL-1b and IL-6. Our results, coupled with the genetic association of SNPs in human TIRAP/Mal with aseptic loosening [5], lead to two conclusions. First, activation of TIRAP/Mal likely contributes to aseptic loosening in patients. Second, pathogen-associated molecular patterns (PAMPs) also likely contribute to aseptic loosening since the results with endotoxin-free Ti particles demonstrate that adherent PAMPs are required for activation of TIRAP/Mal

Aims

This study aimed to assess the performance of an automated multiplex polymerase chain reaction (mPCR) technique for rapid diagnosis of native joint septic arthritis

Aims

Smoking is associated with post-operative complications but smokers often under-report the amount they smoke. Our objective was to determine whether a urine dipstick test could be used as a substitute for quantitative cotinine assays to determine smoking status in patients.

Post-discharge surveillance of surgical site infection is necessary if accurate rates of infection following surgery are to be available. We undertook a prospective study of 376 knee and hip replacements in 366 patients in order to estimate the rate of orthopaedic surgical site infection in the community. The inpatient infection was 3.1% and the post-discharge infection rate was 2.1%. We concluded that the use of telephone interviews of patients to identify the group at highest risk of having a surgical site infection (those who think they have an infection) with rapid follow-up by a professional trained to diagnose infection according to agreed criteria is an effective method of identifying infection after discharge from hospital.