Monitoring of a hip surveillance programme protects infants from radiation and surgical intervention.

AIMS: To monitor the performance of services for developmental dysplasia of the hip (DDH) in Northern Ireland and identify potential improvements to enhance quality of service and plan for the future. METHODS: This was a prospective observational study, involving all infants treated for DDH between 2011 and 2017. Children underwent clinical assessment and radiological investigation as per the regional surveillance policy. The regional radiology data was interrogated to quantify the use of ultrasound and ionizing radiation for this population. RESULTS: Evidence-based changes were made to the Northern Ireland screening programme, including an increase in ultrasound scanning capacity and expansion of nurse-led screening clinics. The number of infant hip ultrasound scans increased from 4,788 in 2011, to approximately 7,000 in 2013 and subsequent years. The number of hip radiographs on infants of less than one year of age fell from 7,381 to 2,208 per year. There was a modest increase in the treatment rate from 10.9 to 14.3 per 1,000 live births but there was a significant reduction in the number of closed hip reductions. The incidence of infants diagnosed with DDH after one year of age was 0.30 per 1,000 live births over the entire period. CONCLUSION: Improving compliance with the regional infant hip screening protocols led to reduction in operative procedures and reduced the number of pelvic radiographs of infants. We conclude that performance monitoring of screening programmes for DDH is essential to provide a quality service. Cite this article: Bone Joint J 2020;102-B(4):495-500.

The Declining Incidence of Legg-Calve-Perthes' Disease in Northern Ireland: An Epidemiological Study.

BACKGROUND: Legg-Calve-Perthes' disease (LCPD) is an idiopathic disease of the femoral head affecting the pediatric population. The causative factors remains poorly understood and it is associated with significant hip pathology in adult life. Research has demonstrated wide geographical variation in the incidence rates of LCPD with a relatively high incidence occurring in Northern Ireland (NI) shown in a previous study of incidence from the same unit. The number of new diagnoses of LCPD seems to be declining over time. This study aimed to track changes in the incidence of LCPD within the 0- to 14-year-old population over a 15-year period in NI. METHODS: An established database was utilized to collate information of any individual between the ages of 0 to 14 years with a diagnosis of LCPD. The data were compared with electronic radiologic records to confirm the diagnosis. Postal code data were used to the determine location of residence and used as a proxy measure of deprivation. RESULTS: The results of this epidemiological study have demonstrated a 61% decrease in the incidence of LCPD over a 15-year period within the pediatric population of NI. Comparison between 2 cohorts reveals no distinguishable change in distribution of age or sex. The relationship between geographical proxy measures of deprivation in NI and LCPD remains evident. CONCLUSIONS: The number of new cases of LCPD is decreasing over time. The epidemiological data are unchanged between 2 cohorts over a 15-year period, and this therefore supports a change within the patients' environment relating to this decline. This change could relate to a number of factors including smoking rates, breastfeeding, lead use, and vaccination implementation. LEVEL OF EVIDENCE: Level IV-retrospective cohort study.

Passive range of motion in a population-based sample of children with spastic cerebral palsy who walk.

While passive range of motion (PROM) is commonly used to inform decisions on therapeutic management, knowledge of PROM of children with spastic cerebral palsy (CP) is limited. A population-based sample of 178 children with spastic CP (110 male; unilateral, n = 94; bilateral, n = 84; age range 4-17 years) and 68 typically developing children (24 male; age range 4-17 years) were recruited to the study. All children were able to walk a minimum of 10 m over a straight flat course, with or without assistive devices. Gross Motor Function Classification System (GMFCS) levels of participants with CP were: Level I = 55, Level II = 88, Level III = 21, and Level IV = 14. Ankle dorsiflexion, knee extension, popliteal angle, hip abduction, hip internal rotation, and hip external rotation were measured using a goniometer. The results indicate that the children with CP had significantly reduced PROM compared to the children with typical development. Children with CP demonstrated reduced length in the hamstrings, hip adductor, iliopsoas and gastrocnemius-soleus musculature, and contracture at the knee joint. Among children with CP, there were significant reductions in range with increasing functional limitation (higher GMFCS level) and variations based on unilateral or bilateral involvement. This was particularly the case for the hamstrings and hip adductor musculature, where PROM varied considerably across GMFCS Levels I to IV.

The time of the insult/triggering event in Legg-Calvé-Perthes' disease determined by incubation period modeling and the age distribution of children with Perthes'.

The time when the insult/triggering event occurs in Legg-Calvé-Perthes' (LCPD) is unknown. the purpose of this study was to determine, using the mathematical tool of incubation period modeling, the time of such event and the incubation period for LCPD. We reviewed 2,911 children with LCPD from 10 different centers around the world. They were divided into two groups: those from India (505 children, mean age 8.1 ± 2.3 years) and those from other than India (2,406 children, mean age 5.8 ± 2.2 years). A simple distribution with an excellent fit to the data was ln(y) = a + bx + cxln(x), where y is the proportion of children with LCPD at age of diagnosis x (r(2) = 0.994 for non-Indian and 0.959 for Indian children). The age of the triggering event was 1.32 years for non-Indian and 2.77 years for Indian children; the median incubation period was 4.30 years non-Indian and 5.33 years for Indian patients. Knowing the incubation period and age of triggering event narrows the number of potential etiologies in LCPD. this study does not support a prenatal triggering event as postulated in the past. similar incubation periods with different ages at diagnosis supports a common insult which occurs at different ages in different populations dependent upon local factors such as geographic location and ethnicity.

Age-related changes in energy efficiency of gait, activity, and participation in children with cerebral palsy.

AIM: The aim of this study was to use a prospective longitudinal study to describe age-related trends in energy efficiency during gait, activity, and participation in ambulatory children with cerebral palsy (CP). METHOD: Gross Motor Function Measure (GMFM), Paediatric Evaluation of Disability Inventory (PEDI), and Lifestyle Assessment Questionnaire-Cerebral Palsy (LAQ-CP) scores, and energy efficiency (oxygen cost) during gait were assessed in representative sample of 184 children (112 male; 72 female; mean age 10y 9mo; range 4-16y) with CP. Ninety-four children had unilateral spastic CP, 84 bilateral spastic CP, and six had other forms of CP. Fifty-seven were classified as Gross Motor Function Classification System (GMFCS) level I, 91 as level II, 22 as level III, and 14 as level IV). Assessments were carried out on two occasions (visit 1 and visit 2) separated by an interval of 2 years and 7 months. A total of 157 participants returned for reassessment. RESULTS: Significant improvements in mean raw scores for GMFM, PEDI, and LAQ-CP were recorded; however, mean raw oxygen cost deteriorated over time. Age-related trends revealed gait to be most inefficient at the age of 12 years, but GMFM scores continued to improve until the age of 13 years, and two PEDI subscales to age 14 years, before deteriorating (p<0.05). Baseline score was consistently the single greatest predictor of visit 2 score. Substantial agreement in GMFCS ratings over time was achieved (κ(lw) =0.74-0.76). INTERPRETATION: These findings have implications in terms of optimal provision and delivery of services for young people with CP to maximize physical capabilities and maintain functional skills into adulthood.

Energy efficiency in gait, activity, participation, and health status in children with cerebral palsy.

The aim of the study was to establish if a relationship exists between the energy efficiency of gait, and measures of activity limitation, participation restriction, and health status in a representative sample of children with cerebral palsy (CP). Secondary aims were to investigate potential differences between clinical subtypes and gross motor classification, and to explore other relationships between the measures under investigation. A longitudinal study of a representative sample of 184 children with ambulant CP was conducted (112 males, 72 females; 94 had unilateral spastic C P, 84 had bilateral spastic C P, and six had non-spastic forms; age range 4-17 y; Gross Motor Function Classification System Level I, n=57; Level II, n=91; Level III, n=22; and Level IV, n=14); energy efficiency (oxygen cost) during gait, activity limitation, participation restriction, and health status were recorded. Energy efficiency during gait was shown to correlate significantly with activity limitations; no relationship between energy efficiency during gait was found with either participation restriction or health status. With the exception of psychosocial health, all other measures showed significant differences by clinical subtype and gross motor classification. The energy efficiency of walking is not reflective of participation restriction or health status. Thus, therapies leading to improved energy efficiency may not necessarily lead to improved participation or general health.

Recruitment bias in a population-based study of children with cerebral palsy.

OBJECTIVE: The purpose of this analysis was to assess recruitment bias in a population-based study of locomotor ability in children with cerebral palsy. METHOD: A population-based case register was used as a sampling frame and was considered a highly ascertained record of children with the condition. A twin track approach to recruitment for the Locomotor Study was adopted through: (1) a specialist orthopedic service and (2) a community pediatric network on behalf of the case register. The subjects included children with cerebral palsy aged 4 to 16 years in 2003, able to walk > or = 10 m, and a resident in Northern Ireland, as well as their parents. RESULTS: The Orthopaedic Service identified clinically distinct children with cerebral palsy in terms of type, severity, age, and geographic residence. More families responded to an invitation, and more were ultimately recruited into the study via the Orthopaedic Service compared with a case register using community pediatric contacts. Overall, 37.8% of the eligible cerebral palsy population participated in the Locomotor Study, but there was no evidence of any systematic biases in demographic or key clinical characteristics when compared with nonparticipants. One follow-up reminder led to an increase in recruitment of 10%. CONCLUSIONS: Care must be taken in the recruitment of children with cerebral palsy through clinic-based populations, although these routes may prove more successful in follow-up. Provided they are comprehensive, case registers have a valuable contribution to make to clinical research by providing a sampling frame including information on baseline characteristics of an affected population.

Endocrine profile and physical stature of children with Perthes disease.

Children with Perthes disease have been thought to be of smaller stature than their peers. No reproducible evidence exists to demonstrate an endocrinopathy as the cause. This study reviewed 139 children with Perthes disease. Height and weight were recorded and compared with standardized growth charts. A blood sample was analyzed for thyroid stimulating hormone (TSH), thyroxin (T4), and insulin-like growth factor 1 (IGF1). Two urine samples were collected at 8 am and 8 pm within 24 hours. From these a cortisol/creatinine ratio was calculated. The results were compared with those from 40 healthy matched controls. No significant differences were found between the study or control children for levels of TSH, T4, IGF1, or cortisol. Review of the height and weight results revealed that the study children were of normal body habitus compared with the general pediatric population and do not undergo a period of growth acceleration following the active stages of the disease.