A nationwide study of Perthes’ disease in Norway was undertaken over a five-year period from January 1996. There were 425 patients registered, which represents a mean annual incidence of 9.2 per 100 000 in subjects under 15 years of age, and an occurrence rate of 1:714 for the country as a whole. There were marked regional variations. The lowest incidence was found in the northern region (5.4 per 100 000 per year) and the highest in the central and western regions (10.8 and 11.3 per 100 000 per year, respectively). There was a trend towards a higher incidence in urban (9.5 per 100 000 per year) compared with rural areas (8.9 per 100 000 per year). The mean age at onset was 5.8 years (1.3 to 15.2) and the male:female ratio was 3.3:1. We compared 402 patients with a matched control group of non-affected children (n = 1 025 952) from the Norwegian Medical Birth Registry and analysed maternal data (age at delivery, parity, duration of pregnancy), birth length and weight, birth presentation, head circumference, ponderal index and the presence of congenital anomalies. Children with Perthes’ disease were significantly shorter at birth and had an increased frequency of congenital anomalies. Applying Sartwell’s log-normal model of incubation periods to the distribution of age at onset of Perthes’ disease showed a good fit to the log-normal curve. Our findings point toward a single cause, either genetic or environmental, acting prenatally in the aetiology of Perthes’ disease

Heritable thrombophilic disorders have been proposed as one of the causes for Legg-Calvé-Perthes disease. A total of 62 patients diagnosed with this disease between 1988 and 1997 and 50 controls were screened for thrombophilia. The incidence and relationship of thrombophilia to the severity of the disease were evaluated. One patient and none of the controls had protein S deficiency. One of the control group and one of the patients had protein C deficiency with the latter child also having a combined deficiency with a mutant factor V gene. The number of children with a mutant factor V gene, protein C deficiency, who were homozygous for the C 677T polymorphism of methylenetetra-hydrofolate reductase or were heterozygous for mutant G20210A prothrombin did not differ statistically in the study and the control groups. No patient had antithrombin deficiency or positive lupus anticoagulant. We found no correlation between thrombophilia and the extent of the disease. The most common risk factors for arteriovenous thromboembolism showed no statistical significance in our patients compared with the control group or with the general population. These data do not confirm an aetiological role for thrombophilia in Perthes’ disease

Aim. Paediatric fractures are common but those occurring in non-ambulant children are associated with higher rates of Non Accidental Injury (NAI). There is little published on the mechanisms of injury associated with accidental fracture in young children. This study explores the aetiology of long bone fractures in non-ambulant children. Methods. This retrospective multicentre study looked at children aged ≤18 months presenting to three hospitals over 3 years (2009 to 2011). Information was gathered on age, gender, fracture type, injury mechanism, final diagnosis, treatment and details of screening for NAI. Results. 147 children were identified who were ≤18 months old (mean 12 months). There were 32 femoral, 37 tibial, 43 forearm, 17 humeral, 16 clavicular and 3 fibular fractures. We identified 6 confirmed cases of NAI and 7 pathological fractures (osteopenia of prematurity or osteogenesis imperfecta). 5/64 children aged ≤12 months old had NAI compared with 1/83 in those aged >12 months. All 7 pathological fractures occurred in the ≤12 months group. NAI or pathological fracture was more likely in ≤12 months group compared to those >12 months (p=0.0002) Of the 12 children with no clear mechanism of injury, 5 had NAI and 3 had pathological fractures. In 39/147 children NAI was considered in the documentation and 29 had a paediatric review. Falls from beds and change mats were more common in ≤12 months group, as well as transverse femoral fractures; caused when those carrying the child slipped downstairs and applied a sudden bending force to the held leg. In those >12 months falls from chairs, down steps, in playgrounds or on trampolines were more common. 12/147 fractures were caused directly by other children (6 in each group). Conclusion. Our study identified causes of accidental long-bone fracture in non-ambulant children. In cases where there is no clear mechanism of injury, NAI must be carefully excluded

This study sought to determine the genetic contribution of Perthes' disease, using the world's largest twin-registry.

We extracted all twin pairs from the Danish Twin Registry (DTR) in which at least one individual had Perthes' Disease. The DTR captures every twin pair born alive in Denmark. Those with Perthes' disease were identified using health record linkage to the Danish Morbidity Record. Probandwise concordance was calculated to describe the likelihood that any given individual had LCPD if their co-twin was also diagnosed.

There were 81 twin pairs; 10 monozygotic (MZ), 51 dizygotic (DZ), and 20 unclassified (UZ). There was no association between birth weight and being the affected co-twin. Four pairs (two dizygotic and two unclassified) were concordant for LCPD, which is greater than would be expected assuming no familial aggregation. There were no concordant MZ twin pairs. The overall probandwise concordance was 0.09 (95% CI 0.01–0.18): 0.00 for the MZ, 0.08 (95% CI 0.00–0.18) for the DZ, and 0.18 (95% 0.00–0.40) for the UZ twin pairs.

This study found evidence of familial clustering in LCPD but did not demonstrate a genetic component. The absolute risk that a co-twin of an affected individual will develop LCPD is low, even in the case of MZ twin pairs.

Aims. We aimed to describe the epidemiological, biological, and bacteriological characteristics of osteoarticular infections (OAIs) caused by Kingella kingae. Methods. The medical charts of all children presenting with OAIs to our institution over a 13-year period (January 2007 to December 2019) were reviewed. Among these patients, we extracted those which presented an OAI caused by K. kingae and their epidemiological data, biological results, and bacteriological aetiologies were assessed. Results. K. kingae was the main reported microorganism in our paediatric population, being responsible for 48.7% of OAIs confirmed bacteriologically. K. kingae affects primarily children aged between six months and 48 months. The highest prevalence of OAI caused by K. kingae was between seven months and 24 months old. After the patients were 27 months old, its incidence decreased significantly. The incidence though of infection throughout the year showed no significant differences. Three-quarters of patients with an OAI caused by K. kingae were afebrile at hospital admission, 11% had elevated WBCs, and 61.2% had abnormal CRPs, whereas the ESR was increased in 75%, constituting the most significant predictor of an OAI. On MRI, we noted 53% of arthritis affecting mostly the knee and 31% of osteomyelitis located primarily in the foot. Conclusion. K. kingae should be recognized currently as the primary pathogen causing OAI in children younger than 48 months old. Diagnosis of an OAI caused by K. kingae is not always obvious, since this infection may occur with a mild-to-moderate clinical and biological inflammatory response. Extensive use of nucleic acid amplification assays improved the detection of fastidious pathogens and has increased the observed incidence of OAI, especially in children aged between six months and 48 months. We propose the incorporation of polymerase chain reaction assays into modern diagnostic algorithms for OAIs to better identify the bacteriological aetiology of OAIs. Cite this article: Bone Joint J 2021;103-B(3):578–583

Aims. To explore the of age of onset distribution for Perthes’ disease of the hip, with particular reference to gender, laterality and conformity to the lognormal distribution. Patients and Methods. A total of 1082 patients were identified from the Liverpool Perthes’ Disease Register between 1976 and 2010, of which 992 had the date of diagnosis recorded. In total, 682 patients came from the geographical area exclusively served by Alder Hey Hospital, of which 673 had a date of diagnosis. Age of onset curves were analysed, with respect to the predefined subgroups. Results. The age of onset demonstrated a positive skew with a median of 5.8 years (interquartile range 4.6 to 7.5). Disease onset was a mean five months earlier in girls (p = 0.01) and one year earlier in those who went on to develop bilateral disease (p < 0.001). There was no difference in the age of onset between geographical districts with differing incidence rates. The entire dataset (n = 992) conformed to a lognormal distribution graphically and with the chi-squared test of normality (p = 0.10), but not using the Shapiro-Wilk test (p = 0.01). The distribution for the predefined geographical subgroup (n = 673) conformed well to a lognormal distribution (chi-squared p = 0.16, Shapiro-Wilk p = 0.08). Given the observed lognormal distribution it was assumed that Perthes’ disease followed on incubation period consistent with a point-source disease exposure. The incubation period was further examined using Hirayama’s method, which suggested that the disease exposure may act in the prenatal period. Conclusion. The age of onset in Perthes’ disease conforms to a lognormal distribution, which allows comparisons with infectious disease epidemiology. Earlier onset in girls and those who develop bilateral disease may offer clues to understanding the aetiological determinants of the disease. The analysis suggests that an antenatal aetiological determinant may be responsible for disease. Take home message: Perthes’ disease age of onset conforms to a lognormal model, which is most typical of infectious diseases. The shape of the distribution suggests that an aetiological trigger in the pre-natal period may be an important determinant of disease. Cite this article: Bone Joint J 2016;98-B:710–14

Perthes’ disease is an osteonecrosis of the juvenile hip, the aetiology of which is unknown. A number of comorbid associations have been suggested that may offer insights into aetiology, yet the strength and validity of these are unclear. This study explored such associations through a case control study using the United Kingdom General Practice Research database. Associations investigated were those previously suggested within the literature. A total of 619 cases of Perthes’ disease were included, as were 2544 controls. The risk of Perthes’ disease was significantly increased with the presence of congenital anomalies of the genitourinary and inguinal region, such as hypospadias (odds ratio (OR) 4.04 (95% confidence interval (CI) 1.41 to 11.58)), undescended testis (OR 1.83 (95% CI 1.12 to 3.00)) and inguinal herniae (OR 1.79 (95% CI 1.02 to 3.16)). Attention deficit hyperactivity disorder was not associated with Perthes’ disease (OR 1.01 (95% CI 0.48 to 2.12)), although a generalised behavioural disorder was (OR 1.55 (95% CI 1.10 to 2.17)). Asthma significantly increased the risk of Perthes’ disease (OR 1.44 (95% CI 1.17 to 1.76)), which remained after adjusting for oral/parenteral steroid use. Perthes’ disease has a significant association with congenital genitourinary and inguinal anomalies, suggesting that intra-uterine factors may be critical to causation. Other comorbid associations may offer insight to support or refute theories of pathogenesis

It has been reported that there is an association between Perthes’ disease and poverty. We examined the demographic data of a group of 240 children (263 hips) who presented with Perthes’ disease in Greater Glasgow, where the mean deprivation scores are substantially greater than in the rest of Scotland, to see if this association applied and whether other clues to the aetiology of Perthes’ disease could be found. There were 197 boys and 43 girls; 39 (16.25%) had a family history of Perthes’ disease. Bone age in this series was heavily skewed towards the lower percentiles. The mean number of siblings was 1.9, with 31 (12.9%) being an only child. Maternal age at the birth of the first child showed no preponderance of older mothers. Maternal smoking during and after pregnancy was noted in 132 (55%), which compared with the 52% reported in the population of Greater Glasgow in general. Of the children in our series, 60 (25%) were in social class IV and V. However, this applies to more than half of the population of Greater Glasgow. There was no significant evidence of a preponderance of Perthes’ disease in the most deprived groups. The aetiology of Perthes’ disease is likely to be multifactorial and may include a genetic or deprivation influence resulting in delayed bone age

Aims

To examine the long-term outcome of arthrodesis of the hip undertaken in a paediatric population in treating painful arthritis of the hip. In our patient population, most of whom live rurally in hilly terrain and have limited healthcare access and resources, hip arthrodesis has been an important surgical option for the monoarticular painful hip in a child.

Aims

The aim of this study was to produce clinical consensus recommendations about the non-surgical treatment of children with Perthes’ disease. The recommendations are intended to support clinical practice in a condition for which there is no robust evidence to guide optimal care.

Children with congenital vertical talus (CVT) have been treated with extensive soft-tissue releases, with a high rate of complications. Recently, reverse Ponseti-type casting followed by percutaneous reduction and fixation has been described, with excellent results in separate cohorts of children with CVT, of either idiopathic or teratological aetiology. There are currently no studies that compare the outcome in these two types. We present a prospective cohort of 13 children (21 feet) with CVT of both idiopathic and teratological aetiology, in which this technique has been used. Clinical, radiological and parent-reported outcomes were obtained at a mean follow-up of 36 months (8 to 57). Six children (nine feet) had associated neuromuscular conditions or syndromes; the condition was idiopathic in seven children (12 feet). Initial correction was achieved in all children, with significant improvement in all radiological parameters. Recurrence was seen in ten feet. Modification of the technique to include limited capsulotomy at the initial operation may reduce the risk of recurrence. The reverse Ponseti-type technique is effective in the initial correction of CVT of both idiopathic and teratological aetiology. Recurrence is a problem in both these groups, with higher rates than first reported in the original paper. However, these rates are less than those reported after open surgical release. Cite this article: Bone Joint J 2014;96-B:274–8

Aims

Perthes’ disease is an idiopathic avascular necrosis of the developing femoral head, often causing deformity that impairs physical function. Current treatments aim to optimize the joint reaction force across the hip by enhancing congruency between the acetabulum and femoral head. Despite a century of research, there is no consensus regarding the optimal treatment. The aim of this study was to describe the experiences of children, their families, and clinicians when considering the treatment of Perthes’ disease.

Aims

Children with spinal dysraphism can develop various musculoskeletal deformities, necessitating a range of orthopaedic interventions, causing significant morbidity, and making considerable demands on resources. This systematic review aimed to identify what outcome measures have been reported in the literature for children with spinal dysraphism who undergo orthopaedic interventions involving the lower limbs.

The aim was to examine the descriptive epidemiology of Slipped Capital Femoral Epiphysis, with respect to geography and time. We extracted all children with a diagnosis of Slipped Capital Femoral Epiphysis from the Clinical Practice Research Database between 1990 and 2014 (24 years). CPRD is the world's largest database of primary care, which encompasses 8% of the UK population. CPRD was linked to Hospital Episode Statistics, and a validation algorithm applied to maximise sensitivity and specificity of the cases finding methodology. Poisson confidence intervals were calculated, and poison regression used. 596 cases of SCFE were identified. The internal validation algorithm supported a SCFE diagnosis in 88% cases. The age and sex distribution of cases mirrored that in the literature, offering external validity to the cases identified. There was no significant change in the incidence of SCFE over the 24-year study period, with the overall incidence being 4.8 cases per 100,00 0–16 year olds. There was no significant geographic variation in SCFE within the UK. There was a positive association with rising socioeconomic deprivation (p<0.01). There was no seasonal variation in presentation. This study found no evidence to support the common belief that SCFE incidence is increasing, and for the first time demonstrated an association with socioeconomic deprivation. The results are important for considering the feasibility of intervention studies, and offer insights into the disease aetiology

The aetiology of congenital club foot is unclear. Although studies on populations, families and twins suggest a genetic component, the mode of inheritance does not comply with distinctive patterns. The Odense-based Danish Twin Registry contains data on all 73 000 twin pairs born in Denmark over the last 130 years. In 2002 all 46 418 twins born between 1931 and 1982 received a 17-page questionnaire, one question of which was ‘Were you born with club foot?’ A total of 94 twins answered ‘Yes’, giving an overall self-reported prevalence of congenital club foot of 0.0027 (95% confidence interval (CI) 0.0022 to 0.0034). We identified 55 complete twin pairs, representing 12 monozygotic, 22 dizygotic same sex (DZ. ss. ), 18 dizygotic other sex (DZ. os. ) and three unclassified. Two monozygotic and 2 DZ. ss. pairs were concordant. The pairwise concordance was 0.17 (95% CI 0.02 to 0.48) for monozygotic, 0.09 (95% CI 0.01 to 0.32) for DZ. ss. and 0.05 (95% CI 0.006 to 0.18) for all dizygotic (DZ. tot. ) twins. We have found evidence of a genetic component in congenital club foot, although non-genetic factors must play a predominant role

Obesity is thought to be an aetiological factor for slipped capital femoral epiphysis (SCFE). We analysed changes in the incidence of SCFE in Scotland over the last two decades. During this period rates of childhood obesity have risen substantially and evidence for a relationship between these changes and the incidence of SCFE was sought. We found that the incidence of SCFE increased from 3.78 per 100 000 children in 1981 to 9.66 per 100 000 in 2000 (R. 2. = 0.715): a two and a half times increase over two decades. It was seen at a younger age, with a fall in the mean age at diagnosis from 13.4 to 12.6 years for boys (p = 0.007) and 12.2 to 11.6 for girls (p = 0.047). More children under eight years old were seen with SCFE in Scotland in the decade to 2000 than in the previous decade (p = 0.002, R. 2. = 0.346). A close correlation was observed between rising childhood obesity over the last 20 years in Scotland and an increasing incidence of SCFE

Aims

The aim of this study was to evaluate the epidemiology and treatment of Perthes’ disease of the hip.

Aims

Slipped upper femoral epiphysis (SUFE) has well documented biochemical and mechanical risk factors. Femoral and acetabular morphologies seem to be equally important. Acetabular retroversion has a low prevalence in asymptomatic adults. Hips with dysplasia, osteoarthritis, and Perthes’ disease, however, have higher rates, ranging from 18% to 48%. The aim of our study was to assess the prevalence of acetabular retroversion in patients presenting with SUFE using both validated radiological signs and tomographical measurements.

Introduction. 2010 marked a century since Perthes' disease was first described, but the aetiology and mechanism remain unknown. Worldwide, the incidence of Perthes' disease varies widely, yet this may be through differences in study design, population denominators or case ascertainment. It is suggested that differential exposure to adverse socioeconomic circumstances may be a key precipitant, although this remains the subject of debate. This work draws on several epidemiological studies that have sought to develop the understanding of Perthes' disease by examining a case register from Merseyside, discharge data from Scotland and the world's largest community disease register. A systematic review was performed to ensure a robustness and homogeneity between published studies in order to allow meaningful comparisons. Methods. Studies were based on data from the Merseyside Perthes' Disease Register (1976–2008), the UK General Practice Research Database (GPRD, 1990–2008) and hospital discharge data for Scotland (2000–2009). Temporal trends and geographic patterns were analysed and the relationship to deprivation investigated. A systematic review of the published literature was used to explore international variations in incidence up to December 2010 focusing upon the influence of race and latitude. Analyses were conducted using Poisson regression. Results. Systematic Review: 21 studies were included which described 27 populations in 16 countries, observing 124 million person years. The annual incidence ranged from 0.2 – 19.1 per 100,000 0–14 year-olds. Race was a key determinant with East Asians least affected and Whites most affected (East Asian IRR 1.0 (Ref), South Asian IRR 2.9 (2.4, 3.5), White IRR 8.8 (8.2, 9.6)). Latitude was a strong predictor of disease, even after adjusting for race. Each 10 degree increase in latitude resulted in the incidence rate increasing by a factor of 1.44 (1.30, 1.58). GPRD Study. There was a dramatic decline in Perthes' disease incidence within the UK, with annual incidence rates falling from 12.2 to 5.7 cases/100,000 0–14 year-olds over the 19 year study period (p<0.001). There was marked geographic variation in incidence with incidence rates in Scotland more than twice those in London (10–39 (95%CI 8.05 – 13.2) vs 4.6 (95% CI 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 most deprived quintile had the highest disease incidence (rate ratio 1.49 (95% CI 1.10 – 2.04)) and, with the exception of London, regional incidence showed a strong linear relationship to regional deprivation score (p<0.01). Merseyside. There was a dramatic decline in Perthes' disease incidence within Liverpool with rates falling from 14.2 to 7.7 cases/100,000 0–14 year-olds over the 34-year study period (p<0.001). Incidence rates similarly halved within the nearby region of Knowsley (p=0.01) but remained largely static in the more affluent regions of Sefton where the incidence has remained around 7.2 cases/100,000 0–14 year-olds (p=0.73). The association with socioeconomic deprivation is striking with over three times the incidence in the most deprived quintile of multiple deprivation compared to the most affluent quintile of IMD (11.5 vs 3.8 cases/100.000 0–14 year-olds (p<0.001). The incidence, by ward region, was strongly correlated to the ward index of deprivation (p<0.001) (IRR 1.014 (1.007 – 1.021)). Scotland. Hospital discharge rates due to Perthes' disease fell annually by 5.6% (95% CI 2.4% – 8.8% p<0.001) between 2000–2010. Given that there has been no significant change in treatment practice during this period and the results of the above studies, this is likely to represent a real change in disease incidence. There was a strong association between socioeconomic deprivation and disease with rates amongst the most deprived quintile more than twice those of the most affluent (RR 2.1 (1.5 – 2.9)). Similar incidence gradients for deprivation were seen in both urban and rural environments. Conclusions. These studies provide strong evidence to suggest a declining incidence of Perthes' disease within the UK and a strong relationship to socioeconomic deprivation. Although Perthes' disease incidence is falling it remains an important cause of child morbidity and exemplifies socioeconomic inequalities in health. The striking UK North–South divide is similar to that seen in adult diseases such as cardiovascular disease and osteoporosis. Latitude has an independent association with disease which may be through the action of sunlight and Vitamin D. A deprivation-related exposure (probably acting prenatally) appears critical but the aetiological determinants remain elusive

Objective. The relationship between the index (2D) to ring finger (4D) is one of the most commonly studied anthropometric measures, which is believed to offer insight into early growth and the foetal environment. This study aimed to determine the relationship between the 2D:4D ratio and the risk of Perthes' disease in children. Methods. The 2D:4D ratio was measured in 144 cases of Perthes' disease, and 144 controls. Cases and controls were frequency matched for age and sex. Measurements were recorded using a digital venier calliper on the palmar surface of the hand. Logistic regression was undertaken adjusting for age, with stratification for sex. Results. There was a significant negative association between Perthe's disease and digit ration in the right hand in affected females OR −0.78 (95% CI 0.65 – 0.93). There was no such association in males 0.97 (0.90 – 1.05). Conclusions. There is a significant association between degree of ‘masculinisation’ and Perthes' disease. This adds evidence to suggest that a significant aetiological component in disease acts prenatally, and may begin to explain the preponderance of disease amongst males