Follow-up radiographs are usually used as the reference standard for the diagnosis of suspected scaphoid fractures. However, these are prone to errors in interpretation. We performed a meta-analysis of 30 clinical studies on the diagnosis of suspected scaphoid fractures, in which agreement data between any of follow-up radiographs, bone scintigraphy, magnetic resonance (MR) imaging, or CT could be obtained, and combined this with latent class analysis to infer the accuracy of these tests on the diagnosis of suspected scaphoid fractures in the absence of an established standard. The estimated sensitivity and specificity were respectively 91.1% and 99.8% for follow-up radiographs, 97.8% and 93.5% for bone scintigraphy, 97.7% and 99.8% for MRI, and 85.2% and 99.5% for CT. The results were generally robust in multiple sensitivity analyses. There was large between-study heterogeneity for the sensitivity of follow-up radiographs and CT, and imprecision about their sensitivity estimates. If we acknowledge the lack of a reference standard for diagnosing suspected scaphoid fractures, MRI is the most accurate test; follow-up radiographs and CT may be less sensitive, and bone scintigraphy less specific

1. Forty-five cases of acute osteomyelitis have been reviewed with the object of determining the causes of relapse. The importance of an early diagnosis and prompt treatment is stressed, and the question of when to stop antibiotic drugs is discussed. 2. The provisional diagnosis was anterior poliomyelitis in seventeen out of forty-five patients; acute osteomyelitis was diagnosed in twelve only. The criteria for making an early diagnosis are discussed, including the value and limitation of blood culture. 3. The place of operation is discussed and certain conclusions are set out

MRI was performed at three centres in Bombay on 24 patients clinically suspected of tuberculosis of the spine but with normal radiographs. There were 11 males and 13 females and their average age was 24 years (11 to 60). 99mTc bone scans were done in 16 patients before MRI. Eleven patients had the diagnosis confirmed by biopsy and the remainder all responded rapidly to specific antituberculous chemotherapy. On T1-weighted images there was a decrease in signal intensity of the involved bone and soft tissues; on T2-weighted images there was increased signal intensity. Depending on the stage of the disease, three different patterns of infection were revealed: osteitis, osteitis with an abscess, and osteitis with or without an abscess plus discitis. The anatomical pattern of involvement, particularly of the soft tissues and the discs, is specific for tuberculous disease. The ability of MRI to detect tuberculosis of the spine earlier than other techniques could reduce bone destruction and deformity and diminish the need for surgical intervention. Despite the specificity of the patterns revealed by MRI, biopsy is recommended during the stage of osteitis to confirm the diagnosis

Infection is a leading indication for revision arthroplasty. Established criteria used to diagnose prosthetic joint infection (PJI) include a range of laboratory tests. Leucocyte esterase (LE) is widely used on a colorimetric reagent strip for the diagnosis of urinary tract infections. This inexpensive test may be used for the diagnosis or exclusion of PJI. Aspirates from 30 total hip arthroplasties (THAs) and 79 knee arthroplasties (KA) were analysed for LE activity. Semi-quantitative reagent strip readings of 15, 70, 125 and 500 white blood cells (WBC) were validated against a manual synovial white cell count (WCC). A receiver operating characteristic (ROC) curve was constructed to determine the optimal cut-off point for the semi-quantitative results. Based on established criteria, six THAs and 15 KAs were classified as infected. The optimal cut-off point for the diagnosis of PJI was 97 WBC. The closest semi-quantitative reading for a positive result was 125 WBC, achieving a sensitivity of 81% and a specificity of 93%. The positive and negative predictive values of the LE test strip were 74% and 95% respectively. The LE reagent strip had a high specificity and negative predictive value. A negative result may exclude PJI and negate the need for further diagnostic tests. Cite this article: Bone Joint J 2015;97-B:1232–6

Atlanto-axial rotatory fixation is one of a spectrum of rotatory abnormalities of the atlanto-axial joint. Rotatory fixation without anterior displacement of the atlas (Type I) has been reported in only a few cases in which there has been a prolonged interval between injury and diagnosis. The majority of these cases eventually required cervical fusion for persistent deformity or instability. Two cases are presented in which this diagnosis was made early with the aid of rotated odontoid radiographs, tomography and computerised axial tomography. Treatment by a short period of halter traction achieved reduction and early return of function. The authors conclude that early recognition and treatment of this rare condition may prevent the subsequent deformity and instability for which cervical fusion has been required

Aims. The aim of this study was to determine the prevalence and characteristics of C-reactive protein (CRP)-negative prosthetic joint infection (PJI) and evaluate the influence of the type of infecting organism on the CRP level. Patients and Methods. A retrospective analysis of all PJIs affecting the hip or knee that were diagnosed in our institution between March 2013 and December 2016 was performed. A total of 215 patients were included. Their mean age was 71 years (. sd. 11) and there were 118 women (55%). The median serum CRP levels were calculated for various species of organism and for patients with acute postoperative, acute haematogenous, and chronic infections. These were compared using the Kruskal–Wallis test, adjusting for multiple comparisons with Dunn’s test. The correlation between the number of positive cultures and serum CRP levels was estimated using Spearman correlation coefficient. Results. Preoperative CRP levels were normal (< 10 mg/l) in 77 patients (35.8%) with positive cultures. Low-virulent organisms were isolated in 66 PJIs (85.7%) with normal CRP levels. When grouping organisms by species, patients with an infection caused by Propionibacterium spp., coagulase-negative staphylococci (CNS), and Enterococcus faecalis had significantly lower median serum CRP levels (5.4 mg/l, 12.2 mg/l, and 23.7 mg/l, respectively), compared with those with infections caused by Staphylococcus aureus and Streptococcus spp. (194 mg/l and 89.3 mg/l, respectively; p < 0.001). Those with a chronic PJI had statistically lower median serum CRP levels (10.6 mg/l) than those with acute postoperative and acute haematogenous infections (83.7 mg/l and 149.4 mg/l, respectively; p < 0.001). There was a significant correlation between the number of positive cultures and serum CRP levels (Spearman correlation coefficient, 0.456; p < 0.001). Conclusion. The CRP level alone is not accurate as a screening tool for PJI and may yield high false-negative rates, especially if the causative organism has low virulence. Aspiration of the joint should be used for the diagnosis of PJI in patients with a chronic painful arthroplasty, irrespective of CRP level. Cite this article: Bone Joint J 2018;100-B:1482–86

Aims. The aim of this study was to establish the diagnostic accuracy of culture of joint aspirate with and without saline injection-reaspiration. Patients and Methods. This is a retrospective analysis of 580 hip and knee aspirations in patients who were deemed to have a moderate to high risk of infection, and who subsequently proceeded to revision arthroplasty over a period of 12 years. It was carried out at a large quaternary referral centre where preoperative aspiration is routine. Results. Fluid was aspirated primarily in 313 (54%) cases and after saline injection-reaspiration of a ‘dry tap’ in 267 (46%) cases. Overall sensitivity and specificity of the diagnostic aspirate were 84% (78% to 89%) and 85% (81% to 88%), respectively. Sensitivity and specificity of saline injection-reaspiration after ‘dry tap’ were 87% (79% to 92%) and 79% (72% to 84%) compared with 81% (71% to 88%) and 90% (85% to 93%) for direct aspiration. Conclusion. Preoperative joint aspiration and culture is a sensitive and specific test for the confirmation of diagnosis in patients at a moderate to high risk of prosthetic joint infection. Culture of saline injection-reaspiration also provides accurate diagnostic information in the event of a ‘dry tap’. Both methods allow susceptibility testing of relevant organisms and are therefore able to guide perioperative antibiotic therapy. Cite this article: Bone Joint J 2018;100-B:749–54

Aims

The aim of this study was to evaluate the performance of metagenomic next-generation sequencing (mNGS) in detecting pathogens from synovial fluid of prosthetic joint infection (PJI) patients.

Cut-off values with highest sensitivity and specificity for the synovial fluid white cell and differential count will facilitate the accurate diagnosis of infection in total knee (TKR) and total hip replacement (THR). All patients undergoing revision TKR or THR for suspected prosthetic joint infection between 2009 and 2011 at two hospitals were identified. A total of 75 patients were included with a mean age of 70.3 years (38 to 89). Synovial fluid was aspirated pre-operatively and peri-prosthetic tissue samples were taken intra-operatively for histological and microbiological examination. Receiver operating characteristic (ROC) plots were constructed for white cell and differential counts in aspirated fluid. The optimal cut-off for TKR and THR was 1590 white cells/µl and 65% neutrophilia. The white cell count cut-off value identified for THR was notably lower than previously quoted in the literature. A cut-off value for white cell count in synovial aspirate in suspected prosthetic joint infection of between 1100 and 1700 white cells/µl is likely to be applicable to both THR and TKR. Cite this article: Bone Joint J 2013;95-B:554–7

A retrospective study of 32 patients with primary tumours of the cauda equina is presented. Most of the patients were initially diagnosed as having prolapsed intervertebral discs and treated accordingly. The correct diagnosis was eventually made, usually after a long delay, and confirmed by myelography. Treatment consisted of laminectomy and excision of the tumour. Only one tumour was frankly malignant; all the remaining patients were relieved of their pain and the majority recovered completely. The exceptions were those patients with long-standing neurological deficits; this highlights the importance of early diagnosis and correct treatment before irreparable damage occurs

A series of 100 patients with pain in the leg was studied and the accuracy of electrical studies in the diagnosis of nerve root lesions was investigated before operation. The electrical studies which were performed on all the patients, included recordings of fibrillation potentials, H-reflex and ankle reflex latencies. This diagnosis technique was found to be more accurate than radiculography or clinical examination and did not give false evidence. Seventy patients were classed as having a lesion of the nerve root. Fifty of these patients were treated surgically. The operation revealed compression of the nerve root by osteophytes arising from degenerative and incompletely dislocated posterior facet joints in 43 patients

Aims

Malreduction of the syndesmosis has been reported in up to 52% of patients after fixation of ankle fractures. Multiple radiological parameters are used to define malreduction; there has been limited investigation of the accuracy of these measurements in differentiating malreduction from inherent anatomical asymmetry. The purpose of this study was to identify the prevalence of positive malreduction standards within the syndesmosis of native, uninjured ankles.

1. Direct injection of contrast material into bone indicates its extreme vascularity, particularly near an epiphysis, and emphasises the extraordinary capacity of the minute periosteal vessels. The nutrient artery of a long bone appears to play little part in its nourishment and may be regarded as a vestigeal structure. 2. The vascular pattern of bone tumours may be investigated by injection of the appropriate artery, and sometimes, if a haemangioma is suspected, by direct injection into the lesion. 3. The examination is easily and quickly carried out by direct arterial puncture under local anaesthesia and injection of 35 per cent diodone. A tourniquet applied distally at the appropriate level is often helpful. 4. A study of the vascular pattern of suspected bone tumours has provided useful information in a positive and negative way, assisting both the diagnosis and the planning of treatment. The pathological diagnosis of some tumours, notably osteosarcomas and haemangiomas, may be made with such assurance that possible dissemination of the tumour by biopsy may be avoided

Aims

Biopsy of the periprosthetic tissue is an important diagnostic tool for prosthetic joint infection (PJI) as it enables the detection of the responsible microorganism with its sensitivity to antibiotics. We aimed to investigate how often the bacteria identified in the tissue analysis differed between samples obtained from preoperative biopsy and intraoperative revision surgery in cases of late PJI; and whether there was a therapeutic consequence.

1. The pathology of avascular necrosis of bone and its relationship to the radiographic changes are considered briefly. 2. The inadequacy of radiographic examination in the early diagnosis of avascular necrosis is stressed. 3. Methods of early assessment of the residual vascularity of a bone mass are discussed. 4. Details of the principles, methods, and results of using radioactive phosphorus in the diagnosis of avascularity of bone are described. 5. The dangers and technical difficulties of using radioactive substances are discussed. 6. The possibility is envisaged that surgeons may soon be able to determine at the time of emergency operation whether the femoral head is dead or alive

1. In the course of 2,668 operations for suspected cartilage lesions 119 errors of diagnosis were revealed. 2. These errors are analysed and certain conclusions are drawn

We evaluated triple-phase bone scintigraphy in the differential diagnosis of peri-prosthetic infection in 46 patients with a total hip replacement or bipolar hemiarthroplasty who were due for revision surgery. There were 18 men and 28 women, with a mean age at operation of 64.6 years (28 to 81). We defined peri-prosthetic infection as an increased uptake of radioisotope in all the phases of triple-phase bone scintigraphy and validated these results against the histological and/or microbiology results in every case. The positive and negative predictive values for the presence of infection were 83% and 93%, respectively. The diagnostic sensitivity was 88% and the specificity was 90%. This study indicates that triple-phase bone scintigraphy is a useful tool in the detection of peri-prosthetic infection and offers a cost-effective method of screening

Forty-two consecutive patients with suspected lumbar disc protrusions were studied prospectively to compare the diagnostic accuracy of low-field strength MRI with that of radiculography. Thirty patients subsequently underwent surgical exploration at 33 levels and the operative findings were compared to both methods of diagnostic imaging. All patients had MRI studies, whilst 29 patients also had radiculography. Both studies were evaluated without prior knowledge of the clinical signs, operative findings or the results of other imaging techniques. MRI predicted the correct diagnosis in 29 of the 33 levels explored, an accuracy of 88%. All discs proven to be abnormal demonstrated a reduced signal from the nucleus pulposus. There were two false positive results and two doubtful cases but no false negatives. Radiculography predicted the correct diagnosis in 24 of 32 levels explored, an accuracy of 75%. There were two false positive results, five doubtfuls and one false negative. The overall accuracy when both tests were considered rose to 94%. Of the remaining 12 patients all except one showed good correlation between the MRI and radiculographic findings. These results indicate that low field strength MRI is slightly better than radiculography in diagnosing lumbar disc protrusions

Thirty-three patients with reflex sympathetic dystrophy were studied prospectively to ascertain the pressure-pain threshold of affected and unaffected limbs. The affected side had a lower threshold which was found to be statistically significant. In all 18 patients with upper limb involvement, the pain threshold was reduced on the affected side, but this applied to only 11 of the 15 with leg involvement. This difference may be because patients with lower limb symptoms had been referred later in the course of the syndrome. We showed by repeated tests that after an average of 49 days there was a slow return to normality. The estimation of pressure-pain thresholds may help in the earlier diagnosis of reflex sympathetic dystrophy