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. The aim of this study was to determine the consensus best practice approach for the investigation and management of children (aged 0 to 15 years) in the UK with musculoskeletal infection (including septic arthritis, osteomyelitis, pyomyositis, tenosynovitis, fasciitis, and discitis). This consensus can then be used to ensure consistent, safe care for children in UK hospitals and those elsewhere with similar healthcare systems. Methods. A Delphi approach was used to determine consensus in three core aspects of care: 1) assessment, investigation, and diagnosis; 2) treatment; and 3) service, pathways, and networks. A steering group of paediatric orthopaedic surgeons created statements which were then evaluated through a two-round Delphi survey sent to all members of the British Society for Children’s Orthopaedic Surgery (BSCOS). Statements were only included (‘consensus in’) in the final agreed consensus if at least 75% of respondents scored the statement as critical for inclusion. Statements were discarded (‘consensus out’) if at least 75% of respondents scored them as not important for inclusion. Reporting these results followed the Appraisal Guidelines for Research and Evaluation. Results. A total of 133 children’s orthopaedic surgeons completed the first survey, and 109 the second. Out of 43 proposed statements included in the initial Delphi, 32 reached ‘consensus in’, 0 ‘consensus out’, and 11 ‘no consensus’. These 11 statements were then reworded, amalgamated, or deleted before the second Delphi round of eight statements. All eight were accepted as ‘consensus in’, resulting in a total of 40 approved statements. Conclusion. In the many aspects of medicine where relevant evidence is not available for clinicians to base their practice, a Delphi consensus can provide a strong body of opinion that acts as a benchmark for good quality clinical care. We would recommend clinicians managing children with musculoskeletal infection follow the guidance in the consensus statements in this article, to ensure care in all medical settings is consistent and safe. Cite this article: Bone Joint J 2023;105-B(7):815–820

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 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

Purpose. To evaluate the efficacy of Kocher's criteria to differentiate between transient synovitis and septic arthritis in children. Methods and results. All children with a presentation of ‘atraumatic limp’ and a proven effusion on hip ultrasound between 2004 and 2009 were included. Patient demographics, details of the clinical presentation and laboratory investigations were documented to identify a response to each of the four variables (Weight bearing status, WCC >12,000 cells/m3, CRP >20mg/L and Temperature >38.5°C). SA was defined based upon culture and microscopy of the operative findings. 311 hips were included within the study. Of these 282 were considered to have transient synovitis. 29 patients met criteria to be classified as SA based upon laboratory assessment of the synovial fluid. The introduction of CRP eliminated the need for a four variable model as the prediction for two variables (CRP and weight bearing status) was of similar efficacy. Treating individuals who were non-weight-bearing and a CRP >20mg/L as SA correctly classified 94.8% individuals, with a sensitivity of 75.9%, specificity of 96.8%, positive predictive value of 71.0%, and negative predictive value of 97.5%. CRP was a significant independent predictor of septic arthritis. Conclusion. Mathematical models using common variables used in clinical practice are a useful way of considering ‘risk’ in SA. However, whilst such models correctly classify the majority of individuals they are by no means failsafe. Such models are more reliable in excluding SA, than including SA, and therefore a clinician's acumen remains important in identifying SA in those individuals with a single abnormal variable

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

We reviewed eight children (ten shoulders) who had suffered neonatal sepsis, after a mean follow-up of 14 years (11 to 15). The delay between the onset of symptoms and diagnosis was one day in five patients, two days in three and seven days in one. All ten shoulders were treated by aspiration, followed by arthrotomy in two. At follow-up, five of the ten shoulders had a full range of movement and the others had minimal restriction of external rotation. Shortening of 10 cm was present in one patient, while two with bilateral involvement had disproportionally short humeri. Early diagnosis and treatment favour the outcome in septic arthritis of the shoulder. With late diagnosis, deformation of the humeral head and shortening of the humerus cause marked cosmetic abnormality but negligible functional loss

The unwell child with an acutely irritable hip poses a diagnostic dilemma. Recent studies indicate that pericapsular myositis may be at least as common as joint infection in the septic child. MRI might therefore be a critical first step to avoid unnecessary hip drainage surgery in the septic child with hip symptoms. We reviewed our own experience with MR imaging in this setting. We searched our PACS system to retrieve MRI scans performed for children with suspected hip sepsis from August 2008 to August 2014 using the following terms: hip, septic arthritis, osteomyelitis, mysositis, abscess, femur, acetabulum. 56 cases fulfilled inclusion criteria that included acute presentation with hip symptoms and 2 or more Kocher criteria for septic arthritis. Recent unsuccessful hip washout was not a contra-indication. 56 patients presented with acute infection around the hip. 47 (84%) had MRI scans before any surgical intervention and 9 (16%) had scans promptly following unsatisfactory hip washout with failure to improve. 20 (36%) were found to have pericapsular myositis. In this group, the infection commonly involved the iliopsoas (4), gluteal (4), piriformis (5) or obturator (7) muscles. 15 (27%) children had proximal femoral or acetabular osteomyelitis and 8 (14%) were diagnosed with septic arthritis. The 13 (23%) remaining scans did not show infection around the hip. This study confirms a high rate of extracapsular foci in septic children presenting with hip irritability. Less than 20% had actual septic arthritis in this series. While drainage of a septic joint should never be delayed in the face of a large joint effusion with debris on US, there is a clear role for MRI scanning in the acute setting when the diagnosis is less certain

Purpose. To assess the initial rise in inflammatory markers in paediatric patients presenting with long bone osteomyelitis and whether this is comparable with that in septic arthritis, and diagnostic. Methods. All radiologically confirmed cases of long bone osteomyelitis without septic arthritis, joint effusion or abscess, in paediatric patients, presenting to one hospital over an eighteen-month period were included. These patients were compared with all culture positive septic arthritides presenting to the same hospital within the same period. Inflammatory markers taken on the day of admission were studied. Results. Thirty-seven patients with osteomyelitis and thirteen with culture positive septic arthritis were identified. The two groups were comparable with regards to age and gender. At presentation 65% of the osteomyelitis patients had an ESR, (erythrocyte sedimentation rate), less than 40mm/hour, 48% below 20mm/hour and 19% within the normal range. 23% of the septic arthritis patients had an ESR below 40mm/hour, and none had an ESR below 20mm/hour or in the normal range. The CRP, (C reactive protein), was in the normal range in 46% of the osteomyelitis patients and none of the septic arthritis patients. The average ESR and CRP in the osteomyelitis patients were 47mm/hour and 35mg/L respectively, while in the septic arthritis group these were 72mm/hour and 107mg/L, (P<0.028). Conclusion. The initial rise in inflammatory markers due to long bone osteomyelitis is significantly less than that in septic arthritis. A proportion of patients with osteomyelitis have normal inflammatory markers at presentation. A high index of suspicion is required, and inflammatory markers, while a useful adjunct to monitoring treatment, may offer false reassurance regarding the initial diagnosis

The aim of this study was determine if the detection of pathology in children with a limp can be optimised by screening with blood tests for raised inflammatory markers. The entry criteria for the study were children (0–15 years) presenting to our hospital Emergency Department from 2012–2015 with a non-traumatic limp or pseudoparalysis of a limb, and no sign of fracture or malignancy on plain radiographs. ESR and CRP blood tests were performed along with other standard investigations. Children with ESR or CRP over 10 underwent MRI scan of their area of pain or tendernesss, with those under 7 years old having general anaesthetic. MRI provided the diagnosis in cases of osteomyelitis, pyomyositis, fasciitis, cellulitis, discitis, as well as non-infective conditions such as malignancy and fracture not visible on plain radiographs. Where a joint effusion was present, the diagnosis of septic arthritis was made from organisms cultured following surgical drainage, or high white cell count in joint fluid if no organisms were cultured. The study was completed once data from 100 consecutive children was available. 64% of children had an infective cause for their symptoms (osteomyelitis, septic arthritis, pyomyositis, fasciitis, cellulitis or discitis). A further 11% had positive findings on MRI from non-infective causes (juvenile idiopathic arthritis, cancer, or occult fracture). The remaining 25% had either a normal scan, or transient synovitis. ESR was a more sensitive marker than CRP, since ESR was raised in 97% of those with abnormal scans, but CRP in only 70%. There were no complications from any of the GA MRI scans. Conclusion: This shows that MRI imaging of all children with a limp and either raised ESR or CRP is a sensitive method to minimise the chance of missing important pathology in this group, and is not wasteful of MRI resources

Panton-Valentine leukocidin secreted by Staphylococcus aureus is known to cause severe skin, soft tissue and lung infections. However, until recently it has not been described as causing life-threatening musculoskeletal infection. We present four patients suffering from osteomyelitis, septic arthritis, widespread intravascular thrombosis and overwhelming sepsis from proven Panton-Valentine leukocidin-secreting Staphylococcus aureus. Aggressive, early and repeated surgical intervention is required in the treatment of these patients. The Panton-Valentine leukocidin toxin not only destroys host neutrophils, immunocompromising the patient, but also increases the risk of intravascular coagulopathy. This combination leads to widespread involvement of bone with glutinous pus which is difficult to drain, and makes the delivery of antibiotics and eradication of infection very difficult without surgical intervention

Aims

We aimed to describe the epidemiological, biological, and bacteriological characteristics of osteoarticular infections (OAIs) caused by Kingella kingae.

Introduction. Septic arthritis of the hip in the newborn baby can result in severe long term sequelae in the form of dislocation of the hip, loss of movement and growth disturbance with leg length discrepancy. Reconstructive procedures for this difficult problem have not been satisfactory. Patient and methods. This series comprises eight patients with septic hip sequelae . All of them had old septic hip and leg length discrepancy ranging from 4 cm to 15 cm. all underwent hip stabilization by pelvic support osteotomy and simultaneous limb lengthening and angular deformities correction using the Ilizarov frame. The age at the operation range from 8 years to 19 years, with an average follow up 4 years. Results. The average of limb lengthening gained was 9cm. All hips remain stable and loss of the range of hip and knee motion was not significant. Other complications include pin tract infection one delayed consolidation of callus and one fracture of callus. Conclusion. The Ilizarov hip reconstruction is a good option for the treatment of the late sequelae of infantile hip infection in adolescents. It should be considered a promising choice for the management of late sequelae of infantile hip infection

Pyomyositis is rarely seen in temperate climates. Typically, it presents with the formation of an abscess requiring surgical drainage and it has been reported as a differential diagnosis for septic arthritis of the hip. We describe the occurrence of pyomyositis of the iliacus muscle in a ten-year-old girl which was diagnosed by MRI and blood culture. Formation of an abscess did not occur despite marked focal inflammation and swelling of the muscle. Conservative treatment with antibiotics alone led to complete clinical and radiological resolution of the infection. We could find no previous description of pyomyositis in a child in the British orthopaedic literature. Orthopaedic surgeons, particularly those with a paediatric interest, should be aware of this condition and its presentation, diagnosis and treatment

A delay in the diagnosis of paediatric acute and subacute haematogenous osteomyelitis can lead to potentially devastating morbidity. There are no definitive guidelines for diagnosis, and recommendations in the literature are generally based on expert opinions, case series and cohort studies.

All articles in the English literature on paediatric osteomyelitis were searched using MEDLINE, CINAHL, EMBASE, Google Scholar, the Cochrane Library and reference lists. A total of 1854 papers were identified, 132 of which were examined in detail. All aspects of osteomyelitis were investigated in order to formulate recommendations.

On admission 40% of children are afebrile. The tibia and femur are the most commonly affected long bones. Clinical examination, blood and radiological tests are only reliable for diagnosis in combination. Staphylococcus aureus is the most common organism detected, but isolation of Kingella kingae is increasing. Antibiotic treatment is usually sufficient to eradicate the infection, with a short course intravenously and early conversion to oral treatment. Surgery is indicated only in specific situations.

Most studies were retrospective and there is a need for large, multicentre, randomised, controlled trials to define protocols for diagnosis and treatment. Meanwhile, evidence-based algorithms are suggested for accurate and early diagnosis and effective treatment.

We describe the technique and results of medial submuscular plating of the femur in paediatric patients and discuss its indications and limitations. Specifically, the technique is used as part of a plate-after-lengthening strategy, where the period of external fixation is reduced and the plate introduced by avoiding direct contact with the lateral entry wounds of the external fixator pins. The technique emphasises that vastus medialis is interposed between the plate and the vascular structures.

A total of 16 patients (11 male and five female, mean age 9.6 years (5 to 17)), had medial submuscular plating of the femur. All underwent distraction osteogenesis of the femur with a mean lengthening of 4.99 cm (3.2 to 12) prior to plating. All patients achieved consolidation of the regenerate without deformity. The mean follow-up was 10.5 months (7 to 15) after plating for those with plates still in situ, and 16.3 months (1 to 39) for those who subsequently had their plates removed. None developed a deep infection. In two patients a proximal screw fractured without loss of alignment; one patient sustained a traumatic fracture six months after removal of the plate.

Placing the plate on the medial side is advantageous when the external fixator is present on the lateral side, and is biomechanically optimal in the presence of a femoral defect. We conclude that medial femoral submuscular plating is a useful technique for specific indications and can be performed safely with a prior understanding of the regional anatomy.

Cite this article: Bone Joint J 2014;96-B:137–42.

The traditional techniques involving an oblique tunnel or triangular wedge resection to approach a central or mixed-type physeal bar are hindered by poor visualisation of the bar. This may be overcome by a complete transverse osteotomy at the metaphysis near the growth plate or a direct vertical approach to the bar. Ilizarov external fixation using small wires allows firm fixation of the short physis-bearing fragment, and can also correct an associated angular deformity and permit limb lengthening.

We accurately approached and successfully excised ten central- or mixed-type bars; six in the distal femur, two in the proximal tibia and two in the distal tibia, without damaging the uninvolved physis, and corrected the associated angular deformity and leg-length discrepancy. Callus formation was slightly delayed because of periosteal elevation and stretching during resection of the bar. The resultant resection of the bar was satisfactory in seven patients and fair in three as assessed using a by a modified Williamson–Staheli classification.

Cite this article: Bone Joint J 2015;97-B:1726–31.

We reviewed three infants with destructive osteomyelitis involving the proximal tibial epiphysis at a follow-up of eight to 22 years. All cases showed early radiographic destructive changes in the medial or lateral aspects of the epiphysis and metaphysis. Despite the ominous early appearance of the epiphysis, all cases showed spontaneous re-ossification of the epiphysis with restoration of the tibial condyle and preservation of joint congruity. The patients, however, developed a valgus or varus deformity which was treated satisfactorily with one to three proximal tibial osteotomies. The potential for regeneration of the epiphysis following infantile osteomyelitis of the proximal tibia suggests these cases should be treated expectantly with regard to joint congruity.