Aims. The aims of this study were to develop an automatic system capable of calculating four radiological measurements used in the diagnosis and monitoring of cerebral palsy (CP)-related hip disease, and to demonstrate that these measurements are sufficiently accurate to be used in clinical practice. Methods. We developed a machine-learning system to automatically measure Reimer’s migration percentage (RMP), acetabular index (ACI), head shaft angle (HSA), and neck shaft angle (NSA). The system automatically locates points around the femoral head and acetabulum on pelvic radiographs, and uses these to calculate measurements. The system was evaluated on 1,650 pelvic radiographs of children with CP (682 females and 968 males, mean age 8.3 years (SD 4.5)). Each radiograph was manually measured by five clinical experts. Agreement between the manual clinical measurements and the automatic system was assessed by mean absolute deviation (MAD) from the mean manual measurement, type 1 and type 2 intraclass correlation coefficients (ICCs), and a linear mixed-effects model (LMM) for assessing bias. Results. The MAD scores were 5.7% (SD 8.5%) for RMP, 4.3° (SD 5.4°) for ACI, 5.0° (SD 5.2°) for NSA, and 5.7° (SD 6.1°) for HSA. Overall ICCs quantifying the agreement between the mean manual measurement and the automatic results were 0.91 for RMP, 0.66 for ACI, 0.85 for NSA, and 0.73 for HSA. The LMM showed no statistically significant bias. Conclusion. The results showed excellent agreement between the manual and automatic measurements for RMP, good agreement for NSA, and moderate agreement for HSA and ACI. The performance of the system is sufficient for application in clinical practice to support the assessment of hip migration based on RMP. The system has the potential to save clinicians time and to improve patient care by enabling more comprehensive, consistent, and reliable monitoring of hip migration in children with CP. Cite this article: Bone Joint J 2025;107-B(1):124–132

Aims. The migration percentage (MP) is one criterion used for surgery in dislocated or displaced hips in children with cerebral palsy (CP). The MP at which a displaced hip can no longer return to normal is unclear. The aim of this paper was to identify the point of no return of the MP through a large population-based study. Methods. All children registered on the Cerebral Palsy Integrated Pathway Scotland surveillance programme undergo regular pelvic radiographs. Any child who had a MP measuring over 35% since the programme’s inception in 2013, in at least one hip and at one timepoint, was identified. The national radiography database was then interrogated to identify all pelvic radiographs for each of these children from birth through to the date of analysis. A minimum of a further two available radiographs following the initial measurement of MP ≥ 35% was required for inclusion. Results. A total of 239 children (346 hips) were identified as suitable for analysis at a mean of 6.5 years (2.0 to 14.8) follow-up. In all, 1,485 radiographs taken both prior to and after a hip had a MP ≥ 35% were examined and the MP measured to identify any progression of displacement. Interrogation of the data identified that hips with a MP up to 46% returned to a MP below 40% without intervention, and all hips with a MP equal to or greater than 46% displaced further and the MP did not return to the normal range. Statistical analysis showed the result to be 98% specific with this degree of certainty that hips reaching a MP ≥ 46% would not spontaneously regress. Conclusion. These findings are clinically relevant in showing that it may be reasonable to continue to monitor hips with a MP not exceeding 46%. This threshold will also guide referral for further management of a displacing hip. Cite this article: Bone Joint J 2021;103-B(2):411–414

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

We present the 2 year results for the first 54 patients after Selective Dorsal Rhizotomy (SDR) delivered in Bristol, concentrating on change in Reimers' migration index. Eligible patients are selected at the SDR multidisciplinary meeting. Physiotherapy assessment is performed pre-operatively and at 6, 12 and 24 months post-surgery. Data collected includes GMFCS, Gross Motor Function Measure (GMFM) 88 and Modified Ashworth score for spasticity for major lower limb muscle groups, amongst other data. Pelvic radiographs are taken pre-operatively and at 2 years post-operatively. Reimers' migration index was measured using the hospital picture archiving and communication system (PACS). The mean age was 7.2 (3.9–17.5) at the time of surgery. Pre- and post-operative pelvic radiographs were available for 30 patients (60 hips). 57% (n=34) hips showed an increase in migration percentage (mean 5.4%, range 0.1–17.5%) and 43% (n=26) hips showed a decrease (mean 4.0%, range 0–15.5%). Overall no significant difference was found in Reimers' migration index at 2 year follow up (mean increase 1.3% (95% CI −0.3–3.0), p=0.12). There was an improvement in GMFCS category (by 1 grade) for 9 patients and a worsening for 1 patient at 2 year follow up. The Modified Ashworth score for spasticity improved in all patients. There was a mean improvement of 1.7 in the hip adductors and 2.4 in the ankle plantar flexors. There was a statistically significant improvement in the GMFM 88 D and E domains of 14.7 (95% CI 11.3–18.1), p<0.0001 and 11.4 (95% CI 7.4–15.7), p<0.0001 respectively. We found no evidence that SDR leads to worsening hip subluxation at 2 year follow up. All patients had improvement in lower limb spasticity. Overall there was a statistically significant improvement in function, as shown by GMFM 88 domains for standing, walking, running and jumping

To evaluate the safety and efficacy of treating patients with Graf IIa developmental hip dysplasia. The management of the developmentally immature Graf Type IIa dysplastic hip is controversial. Some authors advocate early treatment with an abduction harness whilst others adopt watchful waiting. At our institution selective sonographic assessment for developmental dysplasia of the hip (DDH) was established in 1997 with prospective data collection. All infants diagnosed with Graf Type IIa hip(s) were treated with either a Pavlik harness or double nappies, with clinical and sonographic follow up until normalisation. Pelvic radiographs were routinely performed at 8 and 18 months follow up for assessment of residual dysplasia and/or complications of treatment. We evaluated the safety and efficacy of all treated patients between 2005 and 2013. Complete clinical and radiological follow up (mean 2.1 years, 0.7–6.5) was available for 103 of 118 infants. 69 were treated with a Pavlik harness and 49 with double nappies. The chosen treatment was successful in 110 hips with no documented complications, well developed ossific nuclei on follow up radiographs, and no further treatments undertaken. In the double nappy group 4 infants deteriorated sonographically so were changed to a Pavlik harness with subsequent normalisation and successful treatment. 3 patients required VDRO at age 18 months (17–20) and 1 patient required closed reduction and spica cast treatment at age 11 months. No further complications arose in this group. The 15 patients lost to follow up had successful initial treatment but failed to attend for radiographic review. Both Pavlik harness and double nappies are safe treatment modalities for Type IIa hip dysplasia. However, sonographic deterioration was observed in both groups with surgical intervention required in the minority, supporting the ongoing treatment of these immature hips

The purpose of this study was to determine the oblique plane deformity in slipped upper femoral epiphysis. A retrospective radiographic review was undertaken in patients admitted with a slipped upper femoral epiphysis between March 2008 and October 2010. Patients in whom a CT scan had been performed in addition to plain radiographs were assessed further. Angular deformity in the coronal and sagittal planes were measured by the angle formed between the femoral neck and a line perpendicular to the physis on the AP pelvic radiograph and the axial CT scan respectively. The magnitude and direction of the resultant deformity was defined in the oblique plane. Additional demographic data (gender, age, side, procedure and complications) was collected. Seven girls, average age of 12 (range 10 – 13) and 6 boys, average age of 13 (range 10 – 15) were identified. The slip was bilateral in 2, left sided in 6 and right sided in 5 cases. Two patients were pinned in situ, 8 had surgical dislocation performed to facilitate reduction prior to pinning and 3 patients had secondary procedures performed following in situ pinning. The average angulation in the oblique posteroinferior plane (25 degrees) was less than in the coronal (30 degrees) and the sagittal planes (62 degrees). The average magnitude was 67mm (range 31 – 88). CT is useful adjunct particularly when a frog legged lateral view is not possible because of pain or the fear of further displacement. Determination of the deformity in the oblique plane may aid in positioning of the screw during in situ pinning and may be helpful in identifying patients in whom pinning maybe difficult

We have evaluated the reliability of the measurement of radiological indicators in developmental dysplasia of the hip. Three observers each independently assessed 60 pelvic radiographs from infants aged from 3 to 36 months. Errors from the true value of a single measurement made by a single observer (E1), of the average of two measurements by a single observer (E2), and of the average of two single measurements by two different observers (E3) were established for the acetabular index of Hilgenreiner, for the assessment of superior and lateral femoral displacement and for indicators of pelvic alignment. The errors for the assessment of the acetabular index were E1 ± 5°, E2 ± 5°, and E3 ± 3.5°. There was a significant correlation between the presence of an acetabular notch on the radiograph and an increased error in measurement (p = 0.01). Yamamuro’s measurement of lateral femoral displacement was more reliable than the Hilgenreiner distance. The errors of indicators of pelvic alignment showed a correlation with the age of the infant; the quotient of pelvic rotation was more reliable after seven months of age (p < 0.0001). The errors of the measurement of the symphysis os-ischium angle tended to increase with age and those of the measurement of the index of pelvic tilt decreased with skeletal maturation (p = 0.002)

Purpose. To determine whether radiographically demonstrated femoral neck irregularities (pistolgrip-deformity, focal prominences or lytic defects) are associated with positive clinical impingement tests. Methods. The 1989 Bergen birth cohort (n=4004) was invited to a population-based follow-up including clinical examination and two pelvic radiographs. 2081 (52%) were enrolled. Associations between clinical and radiographic findings were examined using chi-squared or Fischer's exact test. Results. Radiographs from 1193, 18-19 year olds, (42% males) have been analysed. For males, irregularities were seen in 128/501 (15.5%) right and 149/501 (19.7%) left hips, of which 13 (10.2%) and 12 (8.1%) had a positive impingement-test respectively (p-values 0.06 and 0.04). The pistolgrip-deformity was seen in 15.8% of right and 19.4% of left hips, of which 6.3% and 7.2% had a positive impingement-test, respectively (p-values 0.6 and 0.3); the focal prominence in 9.2% right and 10% left hips, of which 15.2% and 4% had a positive impingement-test (p-values 0.008 and 0.74) and the lytic defect in 7% right and 8.8% left hips, of which 14.3% and 9.1% had a positive impingement-test (p-values 0.053 and 0.19). For females, irregularities were seen in 34/692 (4.9%) right hips and 46/692 (6.6%) left hips, of which 0 and 2 (4.3%) had a positive impingement-test (p-values 1 and 0.65). Each irregularity was seen in 2-3% of both right and left hips, with no positive impingement tests on the right side and one positive test for each left side, yielding p-values from 0.45 to 1. Conclusion. Femoral neck irregularities are common and symmetrical findings in young males, and are associated with a positive impingement-test. A focal right-sided prominence is associated with a positive test. These radiological findings seem to be less common, but symmetrical, in young females, but without any association with a positive impingement-test

Reimers’ hip migration percentage is commonly used to document the extent of subluxation of the hip in children with spasticity. In this study, two measurers, with six months paediatric orthopaedic experience, measured the migration percentage on 44 pelvic radiographs of children with cerebral palsy, aged between two and eight years. Unknown to the measurers, each radiograph was duplicated, giving 22 non-identical radiographs (44 hips) which were measured twice at time 0 and twice six weeks later. The intra-measurer, intra-sessional absolute differences between the first and second measurements ranged from 0% to 23%, with median values of 2.5% to 3.6%. The intra-sessional median absolute differences were not statistically different between the two measurers and measuring sessions (p = 0.42, Kruskal-Wallis test). The inter-sessional absolute differences for measurements made by the same measurers ranged from 0% to 18% with a median absolute difference of 1.7% to 3.2%. Overall, only 5% of the intra-measurer measurement differences, within and between sessions, were above 13%. Repeated measurements by one measurer over time must, therefore, vary by more than 13% in order to be 95% confident of a true change. The inter-measurer error was higher with median absolute differences between the two measurers’ measurements of the same hip of 3.25% to 5% (0% to 26%) and a 95. th. upper confidence interval of 21% to 23%. Averaging the four separate measurements over the two sessions reduced the inter-measurer error to a median absolute difference of 2.8%, but did not improve the 95. th. upper confidence interval, which measured 22.4%. Such inter-measurer errors may be clinically unacceptable

Aims

The primary aims of this study were to determine the time to sonographic correction of decentred hips during treatment with Pavlik harness for developmental dysplasia of the hip (DDH) and investigate potential risk factors for a delayed response to treatment.

Aims

Abduction bracing is commonly used to treat developmental dysplasia of the hip (DDH) following closed reduction and spica casting, with little evidence to support or refute this practice. The purpose of this study was to determine the efficacy of abduction bracing after closed reduction in improving acetabular index (AI) and reducing secondary surgery for residual hip dysplasia.

Aims

Hip disease is common in children with cerebral palsy (CP) and can decrease quality of life and function. Surveillance programmes exist to improve outcomes by treating hip disease at an early stage using radiological surveillance. However, studies and surveillance programmes report different radiological outcomes, making it difficult to compare. We aimed to identify the most important radiological measurements and develop a core measurement set (CMS) for clinical practice, research, and surveillance programmes.

Aims

Reimers migration percentage (MP) is a key measure to inform decision-making around the management of hip displacement in cerebral palsy (CP). The aim of this study is to assess validity and inter- and intra-rater reliability of a novel method of measuring MP using a smart phone app (HipScreen (HS) app).

Aims

Radiological residual acetabular dysplasia (RAD) has been reported in up to 30% of children who had successful brace treatment of infant developmental dysplasia of the hip (DDH). Predicting those who will resolve and those who may need corrective surgery is important to optimize follow-up protocols. In this study we have aimed to identify the prevalence and predictors of RAD at two years and five years post-bracing.

Aims

The Uppföljningsprogram för cerebral pares (CPUP) Hip Score distinguishes between children with cerebral palsy (CP) at different levels of risk for displacement of the hip. The score was constructed using data from Swedish children with CP, but has not been confirmed in any other population. The aim of this study was to determine the calibration and discriminatory accuracy of this score in children with CP in Scotland.

Aims

Early detection of developmental dysplasia of the hip (DDH) is associated with improved outcomes of conservative treatment. Therefore, we aimed to evaluate a novel screening programme that included both the primary risk factors of breech presentation and family history, and the secondary risk factors of oligohydramnios and foot deformities.

Aims

The aim of this study was to assess the prognostic value of the modified three-group Stulberg classification, which is based on the sphericity of the femoral head, in patients with Perthes’ disease.

Aims

Perthes’ disease (PD) often results in femoral head deformity and leg length discrepancy (LLD). Our objective was to analyze femoral morphology in PD patients at skeletal maturity to assess where the LLD originates, and evaluate the effect of contralateral epiphysiodesis for length equalization on proximal and subtrochanteric femoral lengths.

Aims

The diagnosis of developmental dysplasia of the hip (DDH) is challenging owing to extensive variation in paediatric pelvic anatomy. Artificial intelligence (AI) may represent an effective diagnostic tool for DDH. Here, we aimed to develop an anteroposterior pelvic radiograph deep learning system for diagnosing DDH in children and analyze the feasibility of its application.

Aims

The goal of closed reduction (CR) in the treatment of developmental dysplasia of the hip (DDH) is to achieve and maintain concentricity of the femoral head in the acetabulum. However, concentric reduction is not immediately attainable in all hips and it remains controversial to what degree a non-concentric reduction is acceptable. This prospective study is aimed at investigating the dynamic evolution of the hip joint space after CR in DDH using MRI.