Colin E. Bruce

Osteochondritis dissecans of the knee in children: A COMPARISON OF MRI AND ARTHROSCOPIC FINDINGS

The treatment of osteochondritis dissecans (OCD) in children and adolescents is determined by the stability of the lesion and the state of the overlying cartilage. MRI has been advocated as an accurate way of assessing and staging such lesions. Our aim was to determine if MRI scans accurately predicted the subsequent arthroscopic findings in adolescents with OCD of the knee. Some authors have suggested that a high signal line behind a fragment on the T2-weighted image indicates the presence of synovial fluid and is a sign of an unstable lesion. More recent reports have suggested that this high signal line is due to the presence of vascular granulation tissue and may represent a healing reaction. We were able to improve the accuracy of MRI for staging the OCD lesion from 45% to 85% by interpreting the high signal T2 line as a predictor of instability only when it was accompanied by a breach in the cartilage on the T1-weighted image. We conclude that MRI can be used to stage OCD lesions accurately and that a high signal line behind the OCD fragment does not always indicate instability. We recommend the use of an MRI classification system which correlates with the arthroscopic findings.

Use of elastic stable intramedullary nailing for treating unstable forearm fractures in children.

BACKGROUND The majority of the pediatric diaphyseal forearm fractures are treated with closed reduction and the application of an above elbow cast for a varying period, depending on the age of the child. Some forearm diaphyseal fractures require osteosynthesis mainly because of the presence of an unacceptable angular deformity, fracture instability, presence of an open injury or failure of conservative management in the form of redisplacement in the cast after manipulation. METHODS We present our experience with elastic stable intramedullary nailing (ESIN) for displaced and unstable pediatric diaphyseal fractures. A consecutive series of 21 patients treated with ESIN between 1997 and 2005 have been reviewed retrospectively. There were 14 boys and 7 girls with a median age of 11.8 years. All fixations were protected in an above elbow plaster cast. Patients were followed up for an average of 12.8 months (Range, 12-21.5 months). RESULTS Clinical and radiologic union was achieved within 13 weeks after the procedure in 19 children. One patient had delayed union of the ulna which finally united at 9 months after operation without any further intervention. Another patient had nonunion of ulna that required autologous bone marrow injection after 1 year before full consolidation occurred. Complications were all modest and transient and eventually all patients achieved a good functional clinical outcome. CONCLUSION We think that the technique has many merits over a more traditional plating technique including a minimally invasive technique, a less time consuming procedure and easier metal work removal. We think that cosmesis is perhaps the most important to our patients because the wounds are small and less conspicuous than the traditional Henry approach for plating which leaves a long unsightly volar forearm scar. We think that ESIN is an attractive treatment option for displaced and unstable diaphyseal forearm fractures in children.

Percutaneous Ethibloc injection in aneurysmal bone cysts.

Abstract Objective. To investigate whether the injection of Ethibloc into aneurysmal bone cysts can be an effective treatment modality. Design and patients.Ethibloc is an alcoholic solution of zein (corn protein) which has thrombogenic and fibrogenic properties. Ten patients with aneurysmal bone cysts were treated with CT-guided percutaneous injection of Ethibloc into the cyst cavity. Ethibloc injection was the primary treatment in five patients. Four patients had recurrence following previous curettage and bone grafting and one patient had not responded to injection into the lesion of autologous iliac crest bone marrow aspirate. Three patients needed a second injection. The median follow-up was 27 (6–60) months. Results and conclusion.Symptoms were relieved in all patients. At imaging, seven patients had resolution of the lesion and three had partial response at the most recent follow-up. Complications consisted of a local transitory inflammatory reaction in two patients and an aseptic abscess in one patient. This relatively simple, minimally invasive procedure makes an operation unnecessary by stopping the expansion of the cyst and inducing endosteal new bone formation. This technique may be used as the primary management of aneurysmal bone cysts excluding spinal lesions.

The use of CRP within a clinical prediction algorithm for the differentiation of septic arthritis and transient synovitis in children

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.

Treatment of severely displaced proximal humeral fractures in children with elastic stable intramedullary nailing.

We report on our 8-year experience of using elastic stable intramedullary nailing for severely displaced proximal humeral fractures in children. Fourteen patients (mean age 13.4 years) with seven epiphyseal and seven metaphyseal fractures underwent intramedullary nailing, using single nail fixation in 12 cases. Clinical and radiological healing was achieved at 2.4 and 3.2 months, respectively. Complications included temporary shoulder and elbow stiffness in one and four cases, respectively, one nail breakage at removal, two cases with minor humeral shortening, and two cases with minor varus deformity. At the final (14.6-month) follow up all patients had a symptom-free full range of motion. Elastic stable intramedullary nailing is a valid method of treating severely displaced proximal humeral fractures in children.

Tropical primary pyomyositis in children of the UK: an emerging medical challenge.

Pyomyositis is a commonly encountered condition in the tropics. It was not described in the UK until 1998. The reason for the increasing incidence is not understood. We sought to identify the experience gained of this condition within a UK paediatric tertiary referral unit. Retrospective review of cases of pyomyositis from our institution since 1998 was undertaken to identify demographics, presentation, diagnosis and management. Thirteen cases were identified. The obturator internus was most commonly affected (62%). Staphylococcus aureus was cultured in nine cases (69%). One diagnostic retroperitoneal exploration was performed and all cases were identified by computed tomography or magnetic resonance imaging. To our knowledge, this is the first UK series of pyomyositis, reflecting its increasing Western incidence. Early diagnosis and treatment with antibiotics is all that is needed in the majority of cases. A greater awareness of this emerging condition is necessary to prevent misdiagnosis and unnecessary surgical intervention by all surgeons.

Legg-Calvé-Perthes disease in the UK: geographic and temporal trends in incidence reflecting differences in degree of deprivation in childhood.

OBJECTIVE Little is known about Legg-Calvé-Perthes disease, a common childhood precursor to osteoarthritis of the hip. This study was undertaken to analyze the incidence of Legg-Calvé-Perthes disease in the UK, with respect to geographic and temporal trends over a 19-year period. METHODS The General Practice Research database was analyzed to identify incident cases between 1990 and 2008 in children ages 0-14 years. Incidence rates were calculated by year and by region (National Health Service Strategic Health Authority regions in England, and Scotland, Wales, and Northern Ireland), and the association with regional markers of deprivation examined. RESULTS Over the 19-year period there was a dramatic decline in Legg-Calvé-Perthes disease incidence, with annual rates among children 0-14 years old declining from 12.2 per 100,000 to 5.7 per 100,000 (P < 0.001). There was also marked geographic variation, with incidence rates in Scotland more than twice those in London (10.39 [95% confidence interval 8.05-13.2] versus 4.6 [95% confidence interval 3.4-6.1] per 100,000 0-14-year-olds). A more rapid decline in incidence was apparent in the Northern regions compared to Southern regions. The quintile with the highest degree of deprivation had the highest disease incidence (rate ratio 1.49 [95% confidence interval 1.10-2.04]) and, with the exception of London, regional incidence showed a strong linear relationship with regional deprivation score (P < 0.01). CONCLUSION The incidence of Legg-Calvé-Perthes disease in the UK has a strong North-South divide, with a greater disease incidence within the Northern regions of the UK. There was a marked decline in incidence over the study period, which was more marked in Northern areas. The declining incidence, along with the geographic variation, suggests that a major etiologic determinant in Legg-Calvé-Perthes disease is environmental and closely linked to childhood deprivation.

The association between clubfoot and developmental dysplasia of the hip

The association between idiopathic congenital talipes equinovarus (CTEV) and developmental dysplasia of the hip is uncertain. We present an observational cohort study spanning 6.5 years of selective ultrasound screening of hips in clubfoot. From 119 babies with CTEV there were nine cases of hip dysplasia, in seven individuals. This suggests that 1 in 17 babies with CTEV will have underlying hip dysplasia. This study supports selective ultrasound screening of hips in infants with CTEV.

Evaluating the child who presents with an acute limp

#### Summary points A child may limp after trivial trauma, as a sign of local or systemic disease, or for no apparent reason. When there is a clear history of injury evaluation is usually straightforward. The diagnostic challenge is to distinguish between disease processes that are benign and self limiting (such as transient synovitis), acute or life threatening (such as septic arthritis or acute leukaemia), or chronic and disabling (such as Perthes’ disease). In most cases the causes are benign and self limiting, and around two thirds of patients can be managed in the emergency department and do not require referral to hospital.1 2 #### Sources and selection criteria We searched Google Scholar and Medline (1965-2010) using the terms “limp”, “hip”, “Perthes”, “developmental dysplasia”, “transient synovitis”, “irritable hip”, and “slipped epiphysis”. We also searched bibliographies of retrieved articles for articles not indexed elsewhere and identified references from searches of our files. Only papers published in English were reviewed. No related Cochrane reviews were available. We selected articles if they were the best evidence available or best summary of the evidence. Some articles were included to place the review in historical context. Here, we review the epidemiology of acute limp and outline the pitfalls in diagnosis. We provide a framework for early assessment and management of the child who presents with a limp based on evidence from case series, laboratory studies, observational …

Abnormalities of Vascular Structure and Function in Children With Perthes Disease

BACKGROUND AND OBJECTIVES: Perthes disease is a childhood precipitant to osteoarthritis of the hip, for which the etiology and mechanism are unknown. There is mounting evidence to suggest a vascular insult is responsible for disease, and it is suggested that this may have long-term implications for the vascular health of affected individuals. This study sought to use ultrasound measures to investigate vascular structure and function in children affected by Perthes disease. METHODS: This case control study encompassed 149 cases and 146 controls, frequency matched for age and gender. Endothelial function was measured by using the technique of flow-mediated dilation of the brachial artery, and alterations in arterial flow were recorded in response to an ischemic stimulus. RESULTS: There was a significant structural alteration in the vasculature among individuals with Perthes disease (resting brachial artery diameter (cases 2.97 mm versus controls 3.11 mm; P = .01), which remained even after adjusting for height. In addition, there was a notable reduction in blood velocity (cases 33.84 cm/s versus controls 37.83 cm/s; P = .01) and blood flow (cases 149.82 mL/min versus controls 184.67 mL/min; P = .001), which was independent of baseline arterial size. There was no evidence to suggest that flow-mediated dilation of the brachial artery was impaired among affected individuals (P = .71). CONCLUSIONS: Children with Perthes disease exhibit small artery caliber and reduced function, which is independent of body composition. These data imply that that Perthes disease may reflect a wider vascular phenomenon that could have long-term implications for the vascular health of affected individuals.