Aims. The aim of this study was to compare outcomes after growth-friendly treatment for early-onset scoliosis (EOS) between patients with skeletal dysplasias versus those with other syndromes. Methods. We retrospectively identified 20 patients with skeletal dysplasias and 292 with other syndromes (control group) who had completed surgical growth-friendly EOS treatment between 1 January 2000 and 31 December 2018. We compared radiological parameters, complications, and health-related quality of life (HRQoL) at mean follow-up of 8.6 years (SD 3.3) in the dysplasia group and 6.6 years (SD 2.6) in the control group. Results. Mean major curve correction per patient did not differ significantly between the dysplasia group (43%) and the control group (28%; p = 0.087). Mean annual spinal height increase was less in the dysplasia group (9.3 mm (SD 5.1) than in the control group (16 mm (SD 9.2); p < 0.001). Mean annual spinal growth adjusted to patient preoperative standing height during the distraction period was 11% in the dysplasia group and 14% in the control group (p = 0.070). The complication rate was 1.6 times higher (95% confidence interval (CI) 1.3 to 2.0) in the dysplasia group. The following complications were more frequent in the dysplasia group: neurological injury (rate ratio (RR) 5.1 (95% CI 2.3 to 11)), deep surgical site infection (RR 2.2 (95% CI 1.2 to 4.1)), implant-related complications (RR 2.0 (95% CI 1.5 to 2.7)), and unplanned revision (RR 1.8 (95% CI 1.3 to 2.5)). Final fusion did not provide additional spinal height compared with watchful waiting (p = 0.054). There were no significant differences in HRQoL scores between the groups. Conclusion. After growth-friendly EOS treatment, patients with skeletal dysplasias experienced a higher incidence of complications compared to those with other syndromes. Surgical growth-friendly treatment for skeletal dysplasia-associated EOS should be reserved for patients with severe, progressive deformities that are refractory to nonoperative treatment. Cite this article: Bone Joint J 2024;106-B(6):596–602

Aims. The aim of this study was to compare the surgical and quality-of-life outcomes of children with skeletal dysplasia to those in children with idiopathic early-onset scoliosis (EOS) undergoing growth-friendly management. Patients and Methods. A retrospective review of two prospective multicentre EOS databases identified 33 children with skeletal dysplasia and EOS (major curve ≥ 30°) who were treated with growth-friendly instrumentation at younger than ten years of age, had a minimum two years of postoperative follow-up, and had undergone three or more lengthening procedures. From the same registries, 33 matched controls with idiopathic EOS were identified. A total of 20 children in both groups were treated with growing rods and 13 children were treated with vertical expandable prosthetic titanium rib (VEPTR) instrumentation. Results. Mean preoperative major curves were 76° (34° to 115°) in the skeletal dysplasia group and 75° (51° to 113°) in the idiopathic group (p = 0.55), which were corrected at final follow-up to 49° (13° to 113°) and 46° (12° to 112°; p = 0.68), respectively. T1-S1 height increased by a mean of 36 mm (0 to 105) in the skeletal dysplasia group and 38 mm (7 to 104) in the idiopathic group at the index surgery (p = 0.40), and by 21 mm (1 to 68) and 46 mm (7 to 157), respectively, during the distraction period (p = 0.0085). The skeletal dysplasia group had significantly worse scores in the physical function, daily living, financial impact, and parent satisfaction preoperatively, as well as on financial impact and child satisfaction at final follow-up, than the idiopathic group (all p < 0.05). The domains of the 24-Item Early-Onset Scoliosis Questionnaire (EOSQ24) remained at the same level from preoperative to final follow-up in the skeletal dysplasia group (all p > 0.10). Conclusion. Children with skeletal dysplasia gained significantly less spinal growth during growth-friendly management of their EOS and their health-related quality of life was significantly lower both preoperatively and at final follow-up than in children with idiopathic EOS. Cite this article: Bone Joint J 2019;101-B:1563–1569

Patients with skeletal dysplasia are prone to developing advanced osteoarthritis of the knee requiring total knee replacement (TKR) at a younger age than the general population. TKR in this unique group of patients is a technically demanding procedure owing to the deformity, flexion contracture, generalised hypotonia and ligamentous laxity. We retrospectively reviewed the outcome of 11 TKRs performed in eight patients with skeletal dysplasia at our institution using the Stanmore Modular Individualised Lower Extremity System (SMILES) custom-made rotating-hinge TKR. There were three men and five women with mean age of 57 years (41 to 79). Patients were followed clinically and radiologically for a mean of seven years (3 to 11.5). The mean Knee Society clinical and function scores improved from 24 (14 to 36) and 20 (5 to 40) pre-operatively, respectively, to 68 (28 to 80) and 50 (22 to 74), respectively, at final follow-up. Four complications were recorded, including a patellar fracture following a fall, a tibial peri-prosthetic fracture, persistent anterior knee pain, and aseptic loosening of a femoral component requiring revision. Our results demonstrate that custom primary rotating-hinge TKR in patients with skeletal dysplasia is effective at relieving pain, with a satisfactory range of movement and improved function. It compensates for bony deformity and ligament deficiency and reduces the likelihood of corrective osteotomy. Patellofemoral joint complications are frequent and functional outcome is worse than with primary TKR in the general population

Abstract. Introduction. Total knee replacement (TKR) in patients with skeletal dysplasia is technically challenging surgery due to deformity, joint contracture, and associated co-morbidities. The aim of this study is to follow up patients with skeletal dysplasia following a TKR. Methodology. We retrospectively reviewed 22 patients with skeletal dysplasia who underwent 31 TKRs at our institution between 2006 and 2022. Clinical notes, operative records and radiographic data were reviewed. Results. Achondroplasia was the most common skeletal dysplasia (8), followed by Chondrodysplasia punctata (7) and Spondyloepiphyseal dysplasia (5). There were fourteen men and eight women with mean age of 51 years (28 to 73). The average height of patients was 1.4 metres (1.16–1.75) and the mean weight was 64.8 Kg (34.3–100). The mean follow up duration was 68.32 months (1–161). Three patients died during follow up. Custom implants were required in twelve patients (38.71%). Custom jigs were utilised in six patients and two patients underwent robotic assisted surgery. Hinged TKR was used in seventeen patients (54.84%), posterior stabilised TKR in nine patients (29.03%), and cruciate retaining TKR in five patients (16.13%). One patient underwent a patella resurfacing for persistent anterior knee pain and another had an intra-operative medial tibial plateau fracture which was managed with fixation. No revisions occurred during the follow up period. Conclusion. Despite the technical challenges and complexity of TKR within this unique patient group, we demonstrate good implant survivorship during the study period. Cross sectional imaging is recommended preoperatively for precise planning and templating

Introduction: Total knee arthroplasty (TKA) in patients with skeletal dysplasia is challenging due to the anatomic variances and deformities. The purpose of this review is to understand the technical issues involved in treating these patients. Methods: Clinical notes, operative reports, and radiographs were retrospectively reviewed of 12 knees in 8 patients: 3 achondroplasia patients (one with bilateral 10° varus deformities, one with a 30° varus deformity in one knee and 25° varus deformity in the other knee, one with a 14° varus deformity); 3 multiple hereditary exostosis patients (one with bilateral 45° valgus deformities, one with a 45° valgus deformity in one knee and 15° valgus deformity in the other, one with a 11° valgus deformity); and 2 osteogenesis imperfecta patients (one with a 25° varus deformity, one with a 17° valgus deformity). Results: Surgical exposure required preoperative placement of soft-tissue expanders to avoid wound complications (1 knee), quadriceps snip (2 knees), and hardware removal (1 knee). Intraoperative balancing of the knee was more complex requiring a lateral epicondylar osteotomy (3 knees), medial release (6 knees), lateral retinacular release (6 knees), and proximal realignment to improve patellar tracking (1 knee). 5 knees required a constrained insert, 2 required tibial augments, one required use of cement and screw technique, and one required modification of an all-polyethylene tibia to accommodate the deformed tibial anatomy. 2 knees required custom tibial components. Complications included 2 peroneal nerve palsies which resolved 3 months postoperatively. Range of motion preoperatively averaged 103° (range 45 to 130°) and 100° postoperatively (range 85 to 120°). All patients were pain-free at their last followup (average follow-up 3.9 years). Conclusion: Special considerations must be made regarding surgical exposure, ligament balancing, implant selection, and anticipation of complications due to the unusual deformities when performing TKA in skeletal dysplasia patients

Patients with skeletal dysplasia are prone to developing advanced degenerative knee disease requiring total knee replacement (TKR) at a younger age than the general population. TKR in this unique group of patients is a technically demanding procedure due to the bone deformity, flexion contracture, generalised hypotonia and ligamentous laxity. We set out to retrospectively review the outcome of 11 TKR's performed in eight patients with skeletal dysplasia at our institution using the SMILES custom-made rotating-hinge total knee system. There were 3 males and 5 females with mean age 57 years (range, 41–79 years), mean height 138 cm (range, 122–155 cm) and mean weight 56 kg (range, 40–102 kg). Preoperative diagnoses included achondroplasia, spondyloepiphyseal dysplasia, pseudoachondroplasia, multiple epiphyseal dysplasia, morquio syndrome, diastrophic dysplasia and Larson's Syndrome. Patients were followed clinically and radiographically for a mean of 7 years (range, 3–11.5 years). Knee pain and function improved in all 11 joints. Mean Knee Society clinical and function scores improved from 24 (range, 14–36) and 20 points (range, 5–40) preoperatively to 68 (range, 28–80) and 50 points (range, 22–74) respectively at final follow-up. Four complications were recorded (36%), including a patellar fracture following a fall, a tibial periprosthetic fracture, persistent anterior knee pain and a femoral component revision for aseptic loosening. Our results suggest that custom rotating-hinge TKR in patients with skeletal dysplasia is effective at relieving pain, optimising movement and improving function. It compensates for bony deformity and ligament deficiency and reduces the need for corrective osteotomy. Patellofemoral joint complications are frequent and functional outcome is worse than primary TKR in the general population. Submission endorsed by Mr Peter Calder, Consultant Orthopaedic Surgeon and Society member

An attempt has been made to estimate the number of living people with skeletal dysplasias (osteochondrodysplasias) in Scotland, England and Wales, ascertained through five orthopaedic centres in different parts of Britain. Index patients and their affected relatives were sought and reassessed. Over the 30-year period between 1950 and 1979 inclusive a minimum prevalence was calculated (excluding stillbirths, perinatal deaths, and patients with chromosome anomalies, metabolic bone disease and short stature per se). The results indicate that there were in the community upwards of 10 000 individuals, at various ages over this period, with these largely genetic disorders. A more accurate estimate is of some 6000 of them requiring substantial orthopaedic care, and who were physically handicapped throughout life, about half of them severely so

1. A case is reported of a Jamaican boy of fifteen months with typical and florid manifestations of dysplasia epiphysialis hemimelica associated with a number of atypical features not previously recorded.

2. The progress of the disorder over a limited period of two years is described and the development of the atypical features is discussed.

Introduction. To evaluate the results of correction of knee deformities based on deformity analysis in Achondroplasia, the commonest skeletal dysplasia as some have concomitant ligamentous deformities. Materials and Methods. Retrospective study from a prospective database (2007–2020) of achondroplasts who underwent growth modulation. Analysis of medical records with objective measurement of mechanical axis radiographs was done (Traumacad). Satisfactory alignment was defined as neutral to slightly varus (0–15 mm MAD) so that the MCL/LCL laxity is not revealed. Results. 23 patients, 41 limbs, 34 bilateral, 6 unilateral underwent multiple growth modulation procedures. 2 had valgus knees. 15 patients underwent proximal fibular epiphysiodesis in addition for LCL laxity with one isolated fibular epiphysiodesis. Mechanical axis deviation (MAD) improved or normalised in 16 patients (70%). 4 patients were still undergoing correction. 4 patients needed further surgery out of which 2 patients were over 13 years when growth modulation was attempted and 2 needed correction of ankle varus. JLCA improved/ normalised in 12 patients (75%) with evidence of indirect LCL tightening and no improvement was seen in 4. The rate of correction was MAD 0.61mm/month, LDFA 0.29°/month and MPTA 0.13°/month; expectedly lower in achondroplasia due to lower growth velocity. Conclusions. This study highlights the pathology, application of growth modulation as per deformity analysis unlike previous studies. Proximal fibular epiphysiodesis improves LCL laxity in a majority of these children and is a simple procedure compared to our published series with indirect LCL tightening with frames

The use of total hip arthroplasty in adolescents for end-stage degenerative hip disease is controversial with few reported outcomes in the literature. The purpose of the study was to report the outcomes of total hip arthroplasty in a cohort of adolescents managed by a multidisciplinary team of paediatric and adult orthopaedic surgeons from a single centre. A multidisciplinary clinic consisting of paediatric and adult hip surgeons was established in 2013 to identify, treat and prospectively follow adolescents who would potentially beneift from a total hip arthoplasty. To date 29 consecutive adolescent patients (20 female, 9 male, 32 hips) with end stage degenerative hip disease have undergone cementless primary total hip arthroplasty. Mean age at decision to treat was 15.7 years (age 11.4–18.5). Ten different underlying paediatric specific pathologies were documented including DDH, cerebral palsy, JIA, skeletal dysplasias, SCFE and idiopathic chondrolysis. Three patients had bilateral staged procedures. Clinical baseline and outcomes were measured using Oxford Hip Score (OHS), WOMAC score and ASKp scores. Radiographic follow-up was conducted at 6 weeks, 6 months and yearly thereafter. Post-operative complications were recorded. Twenty-five hips were eligible for minimum 2-year follow-up scoring at a mean 2.7 years (2.0–3.6 years). No intraoperative complications occurred. One case of recalcitrant postoperative psoas tendonitis occured. OHS improved from 25 (7–43) to 41 (23–48). WOMAC improved from 48 (12–8) to 12 (1–44), and ASKp improved from 78% (33–98%) to 93% (73–100%). Radiographic review revealed acceptable alignment of all components with no signs of loosening or wear. No revision of components was required. One patient died at 6 months post op from an unrelated condition. The early term results of total hip arthroplasty in adolescents from our multidisciplinary program are encouraging. Improvements in quality of life to normal values were seen as were hip scores consistent with satisfactory joint function. Depite the range of complex and varied causes of arthritis seen in this population the establishment of combined paediatric and adult orthopaedic surgical teams appears to be a successful model to manage end-stage degenerative hip disease in adolescents

This study aimed to define the rates of lower limb angular correction using temporary hemiepiphysiodesis in differing skeletal pathologies. A retrospective review of 61 children (36M:25F) with angular deformities about the knee who underwent 8-plate hemiepiphysiodesis (mean age 10.8y) was undertaken. The children were divided into 9 groups based on their underlying pathology (lower limb hypoplasia, Blount's disease, skeletal dysplasia, rickets, metabolic disease, acquired growth disturbance, vascular malformation, steroid use and complex genetic disorders). Radiographic measurements of each limb segment was undertaken using the TraumaCad® digital templating software based on standing long-leg radiographs - mechanical lateral distal femoral angle (mLDFA) and mechanical medial proximal tibial angle (mMPTA). The rate of correction of each parameter was calculated as a function of the time lapse between the operation date and first radiographic evidence of full correction of the mechanical axis (zone 1). A total of 144 limb segments (80 distal femoral, 64 proximal tibial physes) were analysed. 62.5% of children had mechanical axes outside the knee joint at the time of operation; 63.2% achieved full correction. The rate of angular correction at the distal femur (mLDFA) was quickest in those with acquired growth disturbance (1.15°/month), complex genetic disorders (1.12°/month) and rickets (0.93°/month). It was slowest in those with vascular malformation (0.40°/month), lower extremity hypoplasia (0.44°/month) and metabolic disease (0.49°/month). At the proximal tibia, mMPTA correction was quickest in those with acquired growth disturbance (0.77°/month) and skeletal dysplasia (0.57°/month); whilst being slowest in those with metabolic disease (0.22°/month) and Blount's disease (0.29°/month). The rate of angular correction about the knee varies with the underlying pathology with correction rates varying up to 3-fold. This study demonstrated the differential rate of correction of angular deformities in children with different skeletal pathologies, which would help guide the timing of hemiepiphysiodesis

Aim. To determine the rate of recurrence of coronal plane deformity in children treated with ‘guided growth’ using 8-plates, from the time of implant removal to skeletal maturity. Methods. Over a consecutive 5 year period between April 2008 and April 2013 we analysed our results of guided growth treatment using 8-plates to correct coronal plane lower limb deformity. Patients with neuromuscular disorders such as cerebral palsy were excluded. Deformity planning was performed using standardised techniques. Our standard practice is to remove the 8-plate and screws once deformity is corrected both clinically and radiologically. Patients were followed up until either skeletal maturity or recurrence, which necessitated reapplication of the 8-plate. We are aware of no study in which children treated with guided growth using 8-plates are followed up to skeletal maturity. Results. 267 patients were treated with 8-plates in our unit over this 5 year period. Of the patients in whom deformity was corrected and had subsequent plates removed, we identified 41 patients who have either reached skeletal maturity or had recurrence of deformity. Six patients required reapplication of the 8-plates implant. These were young and had skeletal dysplasia. Deformity parameters were analysed both clinically and radiologically in patients who have reached skeletal maturity and showed no recurrence, which necessitated further intervention. Conclusion. A higher proportion of younger patients, especially a sub-group with skeletal dysplasia had recurrence of deformity necessitating reapplication of the 8-plate device. In this group we recommend removal of only the metaphyseal screw once deformity is corrected. This would allow ease of reapplication if recurrence were to reoccur. Level of evidence: III

Aim. To study the results of using recombinant human bone morphogenic protein-2 (rhBMP-2) to achieve bone union in children with complex orthopaedic problems including skeletal dysplasia, congenital limb deficiencies and complex trauma. Materials & Methods. Between November 2006 to April 2010, rhBMP-2 was used to achieve bone healing in a total of 19 children. The indications were delayed union or non-union in 16 long bones where previous surgeries had failed and 4 posterior spinal fusions. All children had underlying complex orthopaedic problems predisposing them to delayed bone healing. The average age at the time of surgery was 13 years and 8 months (Range: From 4 years to 19 years and 4 months). There were 7 boys and 12 girls. Results. Average follow-up period was 9.6 months (Range: From 3 months to 2 years and 2 months). Out of the 16 long bone non-unions treated with rhBMP-2, 13 united without further interventions but 3 required further intervention. The average time for clinical union was 10 weeks (Range: from 6 weeks to 18 weeks). The average time for radiological union was 15 weeks (Range: from 7 weeks to 27 weeks). Two children who underwent instrumented posterior spinal fusion and two children who underwent uninstrumented spinal fusion achieved radiologically evident spinal fusion at an average of 16 weeks. No local or systemic complications attributable to BMP were noted in any of the children. Conclusions. rhBMP-2 can be used successfully to achieve bone healing in long bone nonunion and delayed union and posterior spinal fusion in children with complex orthopaedic problems including skeletal dysplasia, congenital limb deficiencies and complex trauma. Its use in children has shown no unwanted effects in the short term. Significance. rhBMP-2 has been approved by Food and Drug Administration (FDA) as a bone graft substitute in adults. Its use in adults has been widely reported but there are only a few case reports of its use in children. This study shows that rhBMP-2 can be safely

Background. Disruption of the normal relationship between the proximal tibia and fibula is seen in a number of different conditions such as skeletal dysplasias and post-infective deformity, as well as the consequence of lengthening procedures. Radiographic indices for the tibio-fibular relationship at the ankle have been described, but no similar measures have been reported for the proximal articulation. Aim. The purpose of this study was to investigate the normal radiographic relationship between the proximal tibia and fibula in children to determine the normal range and variation. Methods. Our radiology database was used to identify a sample of 500 normal anteroposterior radiographs of paediatric knees. All radiographs were reviewed by a single observer. The distance from the corner of the lateral tibial plateau to both the proximal tibial (PT) and fibular physes (PF) were measured, and a ratio of the two calculated (PF/PT). The process was repeated with a sample of 100 radiographs by the same observer, and a second independent observer in order to calculate intra-and inter-observer reliability. Results. The age range of patients in this study was 4–16 years, with mean age 12.7. The mean PF/PT ratio was 1.7 (standard deviation 0.2, range 1.3–2.0). Intra-observer reliability was 100% and inter-observer reliability was 97.8%. Conclusion. The results of this study demonstrate that in the normal paediatric knee, there is a consistent relationship between the position of the proximal tibial and fibular physes, with a small range of variation. The PF/PT ratio is a simple and reliable way of assessing the relationship between the proximal tibia and fibula in children, using a standard anteroposterior radiograph. This ratio could be very useful in the diagnosis and planning of surgical management of a number of different causes of tibial and fibular deformities in children

3D imaging is commonly employed in the surgical planning and management of bony deformity. The advent of desktop 3D printing now allows rapid in-house production of specific anatomical models to facilitate surgical planning. The aim of this pilot study was to evaluate the feasibility of creating 3D printed models in a university hospital setting. For requested cases of interest, CT DICOM images on the local NHS Picture Archive System were anonymised and transferred. Images were then segmented into 3D models of the bones, cleaned to remove artefacts, and orientated for printing with preservation of the regions of interest. The models were printed in polylactic acid (PLA), a biodegradable thermoplastic, on the CubeX Duo 3D printer. PLA models were produced for 4 clinical cases; a complex forearm deformity as a result of malunited childhood fracture, a pelvic discontinuity with severe acetabular deficiency following explantation of an infected total hip replacement, a chronically dislocated radial head causing complex elbow deformity as a result of a severe skeletal dysplasia, and a preoperative model of a deficient proximal tibia as a result of a severe tibia fracture. The models materially influenced clinical decision making, surgical intervention planning and required equipment. In the case of forearm an articulating model was constructed allowing the site of impingement between radius and ulnar to be identified, an osteotomy was practiced on multiple models allowing elimination of the block to supination. This has not previously been described in literature. The acetabulum model allowed pre-contouring of a posterior column plate which was then sterilised and eliminated a time consuming intraoperative step. While once specialist and expensive, in house 3D printing is now economically viable and a helpful tool in the management of complex patients

Aim. Nail patella syndrome (NPS) is a skeletal dysplasia with patellofemoral dysfunction as a key symptom. We present the first in-depth radiological evaluation of the knee in a large series of NPS patients and describe the typical malformations. Patients and Methods. Conventional radiological examination of 95 skeletally mature patients with NPS was performed. Patellar morphology was classified according to the Wiberg classification as modified by Baumgartl and Ficat criteria, and trochlear shape was classified according to the Dejour classification. Results. Patellar aplasia was present in 4/90 (4%), and patellar hypoplasia in 77/90 (86%) of patients. The prevailing patellar shapes were type III, type IV and Hunter’s cap. No patellar shape genotype-phenotype association could be found. The malformations of the distal femur comprised shortening of the lateral femoral condyle in 46 out of 84 patients (55%), with a prominent anterior surface of the lateral femoral condyle in 47 out of 84 patients (56%) and a flat anterior surface of the medial femoral condyle in 78 out of 85 patients (92%). The trochlea was type A1 according to the Dejour classification in 79 out of 85 patients (93%). . Conclusion. An easily recognisable characteristic quartet of malformations consisting of patellar aplasiaor hypoplasia and the malformations of the distal femur was found in 22 out of 81 patients (27%), with the majority displaying at least three malformations. Take home message: The distinct malformations of the knee in nail patella syndrome are easily recognisable on conventional radiographs and lead to the correct interpretation of the aberrant morphology which is essential in the treatment of these patellofemoral disorders. Cite this article: Bone Joint J 2016;98-B:483–9

Aims

As an alternative to external fixators, intramedullary lengthening nails (ILNs) can be employed for distraction osteogenesis. While previous studies have demonstrated that typical complications of external devices, such as soft-tissue tethering, and pin site infection can be avoided with ILNs, there is a lack of studies that exclusively investigated tibial distraction osteogenesis with motorized ILNs inserted via an antegrade approach.

Introduction. Although DDH is one of the most common skeletal dysplasias (incidence 1.5 cases per 1000 births), it remains slow and costly to recruit large-scale patient cohorts for powerful genetic association studies. In this work we have successfully used the NJR as a platform to generate a DDH biobank of 907 individuals, upon which we have conducted the first ever genome-wide association study (GWAS) for DDH. Methods. 5411 patients recorded as having a hip replacement for ‘hip dysplasia’ between March 2003 and December 2013 were approached to participate in the study. Following filtering by questionnaire for non-DDH cases and non-European Caucasians, 907 patients returned a completed saliva sample. A randomly selected sample of individuals participating on the UK Household Longitudinal Study that had been previously genotyped using the same platform were used as controls at a case:control ratio of 1:4. A further data set consisting of 332 cases, 1375 controls and 26 variants was used to replicate the top signals. Results. Of 256833 variants that passed QC, 11 variants reached genome-wide significance. All these variants came from the same signal, with rs143384 as the index SNP (allele A, allele frequency 0.60, OR [95% CI] 1.58[1.40–1.77], P=1.1×10. −14. ). Twenty-six independent variants were prioritized to follow up through de novo replication. Variant rs143384 was found to be significantly associated with DDH after meta-analysing discovery and replication datasets (allele A, allele frequency 0.60, OR [95% CI] 1.50[1.36–1.66], P=2.81×10. −16. ). Discussion. Using eHR case-ascertainment and distance recruitment strategies we conducted the first GWAS for DDH and confirmed association of the GDF5 variant rs143384 with DDH (P=2.81×10. −16. ). We establish the first genome-wide significant locus for DDH, discovered through linking EHRs with genomics as a proof of principle in enabling powerful genetic association studies of relatively rare but complex diseases

Aims

The aim of this retrospective cohort study was to assess and investigate the safety and efficacy of using a distal tibial osteotomy compared to proximal osteotomy for limb lengthening in children.

The long-term results following the correction of coxa vara by Pauwels' Y-shaped intertrochanteric osteotomy have been evaluated in 14 children. Ten of the children had unilateral hip disease and were otherwise normal while four had bilateral hip disease due to generalised skeletal dysplasias. In each case, the growth plate was vertical, the femoral head was displaced inferiorly and there were abnormalities in the metaphysis of the femoral neck. The results indicate that this osteotomy provides lasting correction of the deformity, regardless of the cause, as long as the inclination of the growth plate is corrected to 40 degrees or less and adequate support is provided for the metaphyseal defect and the displaced femoral head