Clinical prediction algorithms are used to differentiate transient synovitis from septic arthritis. These algorithms typically include the erythrocyte sedimentation rate (ESR), although in clinical practice measurement of the C-reactive protein (CRP) has largely replaced the ESR. We evaluated the use of CRP in a predictive algorithm. The records of 311 children with an effusion of the hip, which was confirmed on ultrasound, were reviewed (mean age 5.3 years (0.2 to 15.1)). Of these, 269 resolved without intervention and without long-term sequelae and were considered to have had transient synovitis. The remaining 42 underwent arthrotomy because of suspicion of septic arthritis. Infection was confirmed in 29 (18 had micro-organisms isolated and 11 had a high synovial fluid white cell count). In the remaining 13 no evidence of infection was found and they were also considered to have had transient synovitis. In total 29 hips were categorised as septic arthritis and 282 as transient synovitis. The temperature, weight-bearing status, peripheral white blood cell count and CRP was reviewed in each patient. A CRP > 20 mg/l was the strongest independent risk factor for septic arthritis (odds ratio 81.9, p < 0.001). A multivariable prediction model revealed that only two determinants (weight-bearing status and CRP > 20 mg/l) were independent in differentiating septic arthritis from transient synovitis. Individuals with neither predictor had a < 1% probability of septic arthritis, but those with both had a 74% probability of septic arthritis. A two-variable algorithm can therefore quantify the risk of septic arthritis, and is an excellent negative predictor.

Aims. Septic arthritis of the hip often leads to irreversible osteoarthritis (OA) and the requirement for total hip arthroplasty (THA). The aim of this study was to report the mid-term risk of any infection, periprosthetic joint infection (PJI), aseptic revision, and reoperation in patients with a past history of septic arthritis who underwent THA, compared with a control group of patients who underwent THA for OA. Methods. We retrospectively identified 256 THAs in 244 patients following septic arthritis of the native hip, which were undertaken between 1969 and 2016 at a single institution. Each case was matched 1:1, based on age, sex, BMI, and year of surgery, to a primary THA performed for OA. The mean age and BMI were 58 years (35 to 84) and 31 kg/m. 2. (18 to 48), respectively, and 100 (39%) were female. The mean follow-up was 11 years (2 to 39). Results. The ten-year survival free of any infection was 91% and 99% in the septic arthritis and OA groups, respectively (hazard ratio (HR) = 13; p < 0.001). The survival free of PJI at ten years was 93% and 99% in the septic arthritis and OA groups, respectively (HR = 10; p = 0.002). There was a significantly higher rate of any infection at ten years when THA was undertaken within five years of the diagnosis of septic arthritis compared with those in whom THA was undertaken > five years after this diagnosis was made (14% vs 5%, respectively; HR = 3.1; p = 0.009), but there was no significant difference in ten-year survival free of aseptic revision (HR = 1.14; p = 0.485). The mean Harris Hip Scores at two and five years postoperatively were significantly lower in the septic arthritis group compared with the OA group (p = 0.001 for both). Conclusion. There was a ten-fold increased risk of PJI in patients with a history of septic arthritis who underwent THA compared with those who underwent THA for OA with a ten-year cumulative incidence of 7%. The risk of any infection had a strong downward trend as the time interval between the diagnosis of septic arthritis and THA increased, highlighted by a 3.1-fold higher risk when THAs were performed within five years of the diagnosis being made. Cite this article: Bone Joint J 2022;104-B(2):227–234

Aims. The aim of this study was to determine the extent to which patient demographics, clinical presentation, and blood parameters vary in Kingella kingae septic arthritis when compared with those of other organisms, and whether this difference needs to be considered when assessing children in whom a diagnosis of septic arthritis is suspected. Methods. A prospective case series was undertaken at a single UK paediatric institution between October 2012 and November 2018 of all patients referred with suspected septic arthritis. We recorded the clinical, biochemical, and microbiological findings in all patients. Results. A total of 160 patients underwent arthrotomy for a presumed septic arthritis. Of these, no organism was identified in 61 and only 25 of these were both culture- and polymerase chain reaction (PCR)-negative. A total of 36 patients did not undergo PCR analysis. Of the remaining 99 culture- and PCR-positive patients, K. kingae was the most commonly isolated organism (42%, n = 42). The knee (n = 21), shoulder (n = 9), and hip (n = 5) were the three most commonly affected joints. A total of 28 cases (66%) of K. kingae infection were detected only on PCR. The mean age of K. kingae-positive cases (16.1 months) was significantly lower than that of those whose septic arthitis was due to other organisms (49.4 months; p < 0.001). The mean CRP was significantly lower in the K. kingae group than in the other organism group (p < 0.001). The mean ESR/CRP ratio was significantly higher in K. kingae (2.84) than in other infections (1.55; p < 0.008). The mean ESR and ESR/CRP were not significantly different from those in the 'no organism identified' group. Conclusion. K. kingae was the most commonly isolated organism from paediatric culture- and/or PCR-positive confirmed septic arthritis, with only one third of cases detected on routine cultures. It is important to develop and maintain a clinical suspicion for K. kingae infection in young patients presenting atypically. Routine PCR testing is recommended in these patients. Cite this article: Bone Joint J 2021;103-B(3):584–588

Aims. This study aimed to answer two questions: what are the best diagnostic methods for diagnosing bacterial arthritis of a native joint?; and what are the most commonly used definitions for bacterial arthritis of a native joint?. Methods. We performed a search of PubMed, Embase, and Cochrane libraries for relevant studies published between January 1980 and April 2020. Of 3,209 identified studies, we included 27 after full screening. Sensitivity, specificity, area under the curve, and Youden index of diagnostic tests were extracted from included studies. We grouped test characteristics per diagnostic modality. We extracted the definitions used to establish a definitive diagnosis of bacterial arthritis of a native joint per study. Results. Overall, 28 unique diagnostic tests for diagnosing bacterial arthritis of a native joint were identified. The following five tests were deemed most useful: serum ESR (sensitivity: 34% to 100%, specificity: 23% to 93%), serum CRP (sensitivity: 58% to 100%, specificity: 0% to 96%), serum procalcitonin (sensitivity: 0% to 100%, specificity: 68% to 100%), the proportion of synovial polymorphonuclear cells (sensitivity: 42% to 100%, specificity: 54% to 94%), and the gram stain of synovial fluid (sensitivity: 27% to 81%, specificity: 99% to 100%). Conclusion. Diagnostic methods with relatively high sensitivities, such as serum CRP, ESR, and synovial polymorphonuclear cells, are useful for screening. Diagnostic methods with a relatively high specificity, such as serum procalcitonin and synovial fluid gram stain, are useful for establishing a diagnosis of bacterial arthritis. This review helps to interpret the value of various diagnostic tests for diagnosing bacterial arthritis of a native joint in clinical practice. Cite this article: Bone Joint J 2021;103-B(12):1745–1753

Little information is available about several important aspects of the treatment of melioidosis osteomyelitis and septic arthritis. We undertook a retrospective review of 50 patients with these conditions in an attempt to determine the effect of location of the disease, type of surgical intervention and duration of antibiotic treatment on outcome, particularly complications and relapse. We found that there was a 27.5% risk of osteomyelitis of the adjacent bone in patients with septic arthritis in the lower limb. Patients with septic arthritis and osteomyelitis of an adjacent bone were in hospital significantly longer (p = 0.001), needed more operations (p = 0.031) and had a significantly higher rate of complications and re-presentation (p = 0.048). More than half the patients (61%), most particularly those with multifocal bone and joint involvement, and those with septic arthritis and osteomyelitis of an adjacent bone who were treated operatively, needed more visits to theatre. Cite this article: Bone Joint J 2015;97-B:277–82

Aims. The treatment of septic arthritis of the shoulder is challenging. The infection frequently recurs and the clinical outcome can be very poor. We aimed to review the outcomes following the use of continuous negative pressure after open debridement with a large diameter drain in patients with septic arthritis of the shoulder. Patients and Methods. A total of 68 consecutive patients with septic arthritis of the shoulder underwent arthrotomy, irrigation and debridement. A small diameter suction drain was placed in the glenohumeral joint and a large diameter drain was placed in the subacromial space with continuous negative pressure of 15 cm H. 2. O. All patients received a standardised protocol of antibiotics for a mean of 5.1 weeks (two to 11.1). Results. Negative pressure was maintained for a mean of 24 days (14 to 32). A total of 67 patients (98.5%) were cured without further treatment being required. At a mean follow-up of 14 months (three to 72), the mean forward flexion was 123° (80° to 140°) and the mean external rotation was 28°(10° to 40°) in those with a rotator cuff tear, and 125° (85° to 145°) and 35° (15° to 45°) in those without a rotator cuff tear. Conclusion. Continuous negative pressure, following open arthrotomy, irrigation and debridement, was effective in treating septic arthritis of the shoulder. The rate of recurrence was significantly lower than with conventional treatment involving arthroscopic or open debridement reported in the literature. Functional outcomes, even in patients with rotator cuff tears, were excellent. Take home message: Continuous negative pressure is effective in treating septic arthritis of the shoulder. Cite this article: Bone Joint J 2016;98-B:660–5

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. Patients and Methods. Consecutive patients with suspected septic arthritis undergoing aseptic diagnostic joint aspiration were included. The aspirate was used for analysis by mPCR and conventional microbiological analysis. A joint was classed as septic according to modified Newman criteria. Based on receiver operating characteristic (ROC) analysis, the area under the ROC curve (AUC) values of the mPCR and the synovial fluid culture were compared using the z-test. A total of 72 out of 76 consecutive patients (33 women, 39 men; mean age 64 years (22 to 92)) with suspected septic arthritis were included in this study. Results. Of 72 patients, 42 (58%) were deemed to have septic joints. The sensitivity of mPCR and synovial fluid culture was 38% and 29%, respectively. No significant differences were found between the AUCs of both techniques (p = 0.138). A strong concordance of 89% (Cohen’s kappa: 0.65) was shown. The mPCR failed to detect Staphylococcus aureus (n = 1) and Streptococcus pneumoniae (n = 1; no primer included in the mPCR), whereas the synovial fluid culture missed six microorganisms (positive mPCR: S. aureus (n = 2), Cutibacterium acnes (n = 3), coagulase-negative staphylococci (n = 2)). Conclusion. The automated mPCR showed at least a similar performance to the synovial fluid culture (the current benchmark) in diagnosing septic arthritis, having the great advantage of a shorter turnaround time (within five hours). Cite this article: Bone Joint J 2019;101-B:288–296

The crucial differentiation between septic arthritis and transient synovitis of the hip in children can be difficult. In 1999, Kocher et al introduced four clinical predictors which were highly predictive (99.6%) of septic arthritis. These included fever (temperature ≥ 38.5°C), inability to bear weight, white blood-cell count > 12.0 × 10. 9. cells/L and ESR ≥ 40 mm/hr; CRP ≥ 20 mg/L was later added as a fifth predictor. We retrospectively evaluated these predictors to differentiate septic arthritis from transient synovitis of the hip in children over a four-year period in a primary referral general hospital. When all five were positive, the predicted probability of septic arthritis in this study was only 59.9%, with fever being the best predictor. When applied to low-prevalence diseases, even highly specific tests yield a high number of false positives and the predictive value is thereby diminished. Clinical predictors should be applied with caution when assessing a child with an irritable hip, and a high index of suspicion, and close observation of patients at risk should be maintained

We performed a systematic review of the optimal management of septic arthritis in children as recommended in the current English literature using MEDLINE, EMBASE, CINAHL, the Cochrane Library and reference lists of retrieved articles without date restrictions up to 31 January 2009. From 2236 citations, 227 relevant full-text articles were screened in detail; 154 papers fulfilled the inclusion criteria, from which conclusions were drawn on the management of infected joints in children. Our review showed that no single investigation, including joint aspiration, is sufficiently reliable to diagnose conclusively joint infection. The roles of aspiration, arthrotomy and arthroscopy in treatment are not clear cut, and the ideal duration of antibiotic therapy is not yet fully defined. These issues are discussed. Further large-scale, multi-centre studies are needed to delineate the optimal management of paediatric septic arthritis

We prospectively studied 86 children to assess the value and accuracy of isotope bone scanning in the diagnosis of suspected acute haematogenous osteomyelitis and septic arthritis. The patients were scanned because of difficulty in localising the exact site of the pathology. Characteristic scan appearances were found. In osteomyelitis there was increased or decreased uptake extending beyond the confines of the joint capsule; in septic arthritis there was increased or decreased uptake on either side of the joint line, but largely limited to and uniform within the joint capsule. The bone-scan images were correlated with the final diagnosis in 34 sites of septic arthritis and in 62 sites of osteomyelitis. The overall accuracy of the bone scans was 81%. The predictive value for a positive scan to be correct was 100% for a cold scan and 82% for a hot scan. The main reason for a false-positive scan was contiguous soft-tissue infection. The predictive value for a negative scan to be correct was 63%. One reason for a false-negative scan was that the patient was in the transitional phase from cold to hot

We undertook a prospective study of 61 children in Malawi with septic arthritis of the shoulder. They were randomised into two groups, treated by aspiration (group 1, 31 patients) or arthrotomy (group 2, 30 patients). Both received antibiotics for six weeks. We studied the results of blood tests, microbiology, and the clinical and radiological outcome one year after diagnosis. Only one patient was sickle-cell positive and three were HIV-positive. Non-typhoidal Salmonella species accounted for 86% (19/22) of the positive joint cultures in group 1 and 73% (16/22) in group 2. Of the 33 radiographs available for review at follow-up at six months, 23 (70%) showed evidence of glenohumeral damage. There was no statistical difference in radiological outcome for the two groups. We devised and validated a scoring system, the Blantyre Septic Joint Score, for the assessment of joints based upon swelling, tenderness, function and range of movement. Despite the radiological changes only one of the 24 joints examined at one year had any deficit in these parameters. There was no statistical difference in the clinical outcome for the two treatment groups at any stage during the period of follow-up

In many countries Haemophilus influenzae type b (Hib) is the second most common cause of septic arthritis in children. In Finland large-scale immunisation against Hib using conjugate vaccines began in 1986, four years after a multicentre prospective study of orthopaedic infections in children had started. Since 1982, including six years before and ten after starting routine Hib vaccination, there has been a major change in the pattern of septic arthritis. From 1982 to 1988, 32 of 61 cases (53%) were caused by staphylococci, 22 (36%) by Hib and 7 (11%) by other bacteria. Since 1988, Hib infection has disappeared, and one-third of cases of childhood septic arthritis has been eliminated. This change has allowed us to reduce initial antimicrobial therapy for such children to cover only Gram-positive cocci. The more limited treatment is safer, reduces cost, and simplifies treatment

We examined 204 children (137 boys and 67 girls) aged 12 years and under with septic arthritis. Their mean age was 31.1 months (1 to 144; SD 41.6). The most common joints affected were the knees and shoulders. Joints in the upper limb were affected more often in younger children and in the lower limb in those who were older. The mean age for an infection was 12 months in the shoulder and 73 months in the hip. The most common organisms cultured were species of Salmonella

We reviewed the records of 1,156 patients treated for acute staphylococcal osteitis or septic arthritis over a 12-year period; 38 had been critically ill with evidence of multiple-organ involvement and 30 (79%) had features of the toxic shock syndrome. The mortality rate of these 38 patients was 13% and the long-term orthopaedic complication rate was 39%. The diagnosis and management of patients with osteitis or septic arthritis, disseminated staphylococcal disease, and the toxic shock syndrome is discussed

We have reviewed 61 children treated for septic arthritis from 1972 to 1981. The diagnosis in all cases was confirmed by bacteriology or by radiographic changes. Routine arthrotomy was not performed, but most patients had a joint aspiration. The management and outcome are described. We suggest that arthrotomy should be selective rather than mandatory. Septic arthritis of the hip in infants requires arthrotomy, but in the older child an infected hip can be treated by aspiration if the duration of symptoms is less than four days; arthrotomy may be needed if there has been more delay. Infected joints other than the hip can be satisfactorily managed by aspiration

Septic arthritis has been regarded as rare in haemophiliacs, but its incidence may have increased since HIV infection has become widespread in these patients. We describe six cases treated at one haemophilia unit over a two-year period and discuss their investigation, diagnosis and treatment. Four of the patients were seropositive to anti-HIV

We reviewed 16 patients with salmonella osteitis or septic arthritis. All patients were immunologically normal and none had a history of typhoid fever. We discuss the importance of obtaining a bacteriological diagnosis and provide guidelines on the duration of antibiotic treatment

1. Septic arthritis of the hip in adults is not common and the diagnosis can be difficult. The value of diagnostic aspiration is emphasised. 2. Predisposing causes in fifty patients are analysed and the possible relationship to pelvic infection is discussed. 3. Loss of joint space is occasionally seen within one week of the onset of the infection. 4. A method of treatment is suggested and the value of decompression by arthrotomy is discussed

We performed 52 total hip replacements in 52 patients using a cementless acetabular component combined with a circumferential osteotomy of the medial acetabular wall for the late sequelae of childhood septic arthritis of the hip. The mean age of the patients at operation was 44.5 years (22 to 66) and the mean follow-up was 7.8 years (5 to 11.8). The mean improvement in the Harris Hip Score was 29.6 points (19 to 51) at final follow-up. The mean cover of the acetabular component was 98.5% (87.8% to 100%). The medial acetabular wall was preserved with a mean thickness of 8.3 mm (1.7 to 17.4) and the mean length of abductor lever arm increased from 43.4 mm (19.1 to 62) to 54.2 mm (36.5 to 68.6). One acetabular component was revised for loosening and osteolysis 4.5 years postoperatively, and one had radiolucent lines in all acetabular zones at final review. Kaplan-Meier survival was 94.2% (95% confidence interval 85.8% to 100%) at 7.3 years, with revision or radiological loosening as an end-point when two hips were at risk. A cementless acetabular component combined with circumferential medial acetabular wall osteotomy provides favourable results for acetabular reconstruction in patients who present with late sequelae of childhood septic hip arthritis

The operative treatment of septic arthritis of the shoulder in infants has been facilitated by the use of a 30° wrist arthroscope. We have treated three children under the age of three years using this technique. After initial aspiration of the joint, an arthroscope was inserted using the posterior approach. Washout was performed under direct vision and complete clearance of pus allowed assessment of the inflammation and the damage to articular cartilage. The procedure was minimally invasive and gave excellent cosmesis without compromising care. Full recovery was achieved with a single intervention