Aims. The aim of this study was to compare outcomes of guided growth and varus osteotomy in treating Kalamchi type II avascular necrosis (AVN) after open reduction and Pemberton acetabuloplasty for developmental dysplasia of the hip (DDH). Methods. This retrospective study reviewed patients undergoing guided growth or varus osteotomy for Kalamchi type II AVN between September 2009 and January 2019. All children who had undergone open reduction and Pemberton acetabuloplasty for DDH with a minimum two-year follow-up were enrolled in the study. Demographic and radiological data, which included the head-shaft angle (HSA), neck-shaft angle (NSA), articulotrochanteric distance (ATD), Sharp angle (SA), and lateral centre-edge angle (LCEA) at baseline, two years, and at the extended follow-up, were compared. Revision rates were evaluated. Clinical outcomes using the Harris Hip Score were assessed two years postoperatively. Results. A total of 24 patients underwent guided growth and 19 underwent varus osteotomy, over a mean period of 3.3 years (95% confidence interval (CI) 2.8 to 3.8) and 5.2 years (95% CI 4.5 to 6.0), respectively. There were no differences in demographic and preoperative radiological data, except for a younger age at time of acetabuloplasty and larger ATD for the osteotomy group. The HSA did not differ at two years and the extended follow-up because of postoperative rebound in the osteotomy group. The NSA of the osteotomy group remained smaller postoperatively. There were no significant differences in the follow-up ATD, SA, and LCEA, except for a smaller two-year ATD of the osteotomy group. Seven patients (29.2%) in the guided growth group underwent revision surgery and none in the osteotomy group. The Harris Hip Score was similar between groups. Conclusion. Guided growth and varus osteotomy had comparable results in improving caput valgum deformity, given the rebound of lateral tilting of the physis after osteotomy correction. There were no differences in clinical outcomes at two years postoperatively. Cite this article: Bone Joint J 2022;104-B(7):902–908

Aims. The most important complication of treatment of developmental dysplasia of the hip (DDH) is avascular necrosis (AVN) of the femoral head, which can result in proximal femoral growth disturbances leading to pain, dysfunction, and eventually to early onset osteoarthritis. In this study, we aimed to identify morphological variants in hip joint development that are predictive of a poor outcome. Methods. We retrospectively reviewed all patients who developed AVN after DDH treatment, either by closed and/or open reduction, at a single institution between 1984 and 2007 with a minimal follow-up of eight years. Standard pelvis radiographs obtained at ages one, two, three, five, and eight years, and at latest follow-up were retrieved. The Bucholz-Ogden classification was used to determine the type of AVN on all radiographs. Poor outcome was defined by Severin classification grade 3 or above on the latest follow-up radiographs and/or the need for secondary surgery. With statistical shape modelling, we identified the different shape variants of the hip at each age. Logistic regression analysis was used to associate the different modes or shape variants with poor outcome. Results. In all, 135 patients with AVN were identified, with a minimum of eight years of follow-up. Mean age at time of surgery was 7.0 months (SD 0.45), and mean follow-up was 13.3 years (SD 3.7). Overall, 46% had AVN type 1 while 54% type 2 or higher. More than half of the patients (52.6%) had a poor outcome. We found 11 shape variants that were significantly associated with a poor outcome. These shape variants were predominantly linked to AVN type 2 or higher. Conclusion. Specific morphological characteristics on pelvis radiographs of AVN hips were predictive for poor outcome, at a very young age. There was an overall stronger association to Bucholz-Ogden types 2-3-4 with the exception of two modes at age two and five years, linked to AVN type 1. Cite this article: Bone Joint J 2021;103-B(5):999–1004

Aims. The aim of this study was to clarify the factors that predict the development of avascular necrosis (AVN) of the femoral head in children with a fracture of the femoral neck. Patients and Methods. We retrospectively reviewed 239 children with a mean age of 10.0 years (. sd. 3.9) who underwent surgical treatment for a femoral neck fracture. Risk factors were recorded, including age, sex, laterality, mechanism of injury, initial displacement, the type of fracture, the time to reduction, and the method and quality of reduction. AVN of the femoral head was assessed on radiographs. Logistic regression analysis was used to evaluate the independent risk factors for AVN. Chi-squared tests and Student’s t-tests were used for subgroup analyses to determine the risk factors for AVN. Results. We found that age (p = 0.006) and initial displacement (p = 0.001) were significant independent risk factors. Receiver operating characteristic (ROC) curve analysis indicated that 12 years of age was the cut-off for increasing the rate of AVN. Severe initial displacement (p = 0.021) and poor quality of reduction (p = 0.022) significantly increased the rate of AVN in patients aged 12 years or greater, while in those aged less than 12 years, the rate of AVN significantly increased only with initial displacement (p = 0.048). A poor reduction significantly increased the rate of AVN in patients treated by closed reduction (p = 0.026); screw and plate fixation was preferable to cannulated screw or Kirschner wire (K-wire) fixation for decreasing the rate of AVN in patients treated by open reduction (p = 0.034). Conclusion. The rate of AVN increases with age, especially in patients aged 12 years or greater, and with the severity of displacement. In patients treated by closed reduction, anatomical reduction helps to decrease the rate of AVN, while in those treated by open reduction, screw and plate fixation was preferable to fixation using cannulated screws or K-wires. Cite this article: Bone Joint J 2019;101-B:1160–1167

Aims

The aim of this study was to evaluate the correlation between Salter’s criteria and Kalamchi’s classification of avascular necrosis in patients treated for developmental dysphasia of the hip (DDH).

Aims. The aim of this study was to inform the epidemiology and treatment of slipped capital femoral epiphysis (SCFE). Methods. This was an anonymized comprehensive cohort study, with a nested consented cohort, following the the Idea, Development, Exploration, Assessment, Long-term study (IDEAL) framework. A total of 143 of 144 hospitals treating SCFE in Great Britain participated over an 18-month period. Patients were cross-checked against national administrative data and potential missing patients were identified. Clinician-reported outcomes were collected until two years. Patient-reported outcome measures (PROMs) were collected for a subset of participants. Results. A total of 486 children (513 hips) were newly affected, with a median of two patients (interquartile range 0 to 4) per hospital. The annual incidence was 3.34 (95% confidence interval (CI) 3.01 to 3.67) per 100,000 six- to 18-year-olds. Time to diagnosis in stable disease was increased in severe deformity. There was considerable variation in surgical strategy among those unable to walk at diagnosis (66 urgent surgery vs 43 surgery after interval delay), those with severe radiological deformity (34 fixation with deformity correction vs 36 without correction) and those with unaffected opposite hips (120 prophylactic fixation vs 286 no fixation). Independent risk factors for avascular necrosis (AVN) were the inability of the child to walk at presentation to hospital (adjusted odds ratio (aOR) 4.4 (95% CI 1.7 to 11.4)) and surgical technique of open reduction and internal fixation (aOR 7.5 (95% CI 2.4 to 23.2)). Overall, 33 unaffected untreated opposite hips (11.5%) were treated for SCFE by two-year follow-up. Age was the only independent risk factor for contralateral SCFE, with age under 12.5 years the optimal cut-off to define ‘at risk’. Of hips treated with prophylactic fixation, none had SCFE, though complications included femoral fracture, AVN, and revision surgery. PROMs demonstrated the marked impact on quality of life on the child because of SCFE. Conclusion. The experience of individual hospitals is limited and mechanisms to consolidate learning may enhance care. Diagnostic delays were common and radiological severity worsened with increasing time to diagnosis. There was unexplained variation in treatment, some of which exposes children to significant risks that should be evaluated through randomized controlled trials. Cite this article: Bone Joint J 2022;104-B(4):519–528

Avascular necrosis is a serious complication of slipped capital femoral epiphysis and is difficult to treat. The reported incidence varies from 3% to 47% of patients. The aims of treatment are to maintain the range of movement of the hip and to prevent collapse of the femoral head. At present there are no clear guidelines for the management of this condition and treatment can be difficult and unrewarding. We have used examination under anaesthesia and dynamic arthrography to investigate avascular necrosis and to determine the appropriate method of treatment. We present 20 consecutive cases of avascular necrosis in patients presenting with slipped capital femoral epiphysis and describe the results of treatment with a mean follow-up of over eight years (71 to 121 months). In patients who were suitable for joint preservation (14), we report a ten-year survivorship of the hip joint of 75% and a mean Harris hip score of 82 (44 to 98)

We investigated the incidence and risk factors for the development of avascular necrosis (AVN) of the femoral head in the course of treatment of children with cerebral palsy (CP) and dislocation of the hip. All underwent open reduction, proximal femoral and Dega pelvic osteotomy. The inclusion criteria were: a predominantly spastic form of CP, dislocation of the hip (migration percentage, MP > 80%), Gross Motor Function Classification System, (GMFCS) grade IV to V, a primary surgical procedure and follow-up of > one year. There were 81 consecutive children (40 girls and 41 boys) in the study. Their mean age was nine years (3.5 to 13.8) and mean follow-up was 5.5 years (1.6 to 15.1). Radiological evaluation included measurement of the MP, the acetabular index (AI), the epiphyseal shaft angle (ESA) and the pelvic femoral angle (PFA). The presence and grade of AVN were assessed radiologically according to the Kruczynski classification. Signs of AVN (grades I to V) were seen in 79 hips (68.7%). A total of 23 hips (18%) were classified between grades III and V. Although open reduction of the hip combined with femoral and Dega osteotomy is an effective form of treatment for children with CP and dislocation of the hip, there were signs of avascular necrosis in about two-thirds of the children. There was a strong correlation between post-operative pain and the severity of the grade of AVN. Cite this article: Bone Joint J 2015;97-B:270–6

In order to determine the incidence of avascular necrosis after osteotomy of the talar neck, we re-evaluated 11 patients (16 feet) with idiopathic club foot who had undergone this procedure at a mean age of eight years (5 to 13) to correct a residual adduction deformity. All had been initially treated conservatively and operatively. The mean follow-up was 39 years (36 to 41). Surgery consisted of a closing-wedge osteotomy of the talar neck combined, in 14 feet, with lengthening of the first cuneiform and a Steindler procedure. At follow-up eight feet were free from pain, three had occasional mild pain and five were regularly painful after routine activities. Two patients were unlimited in their activity, six occasionally limited after strenuous and three regularly limited after strenuous activity. Using the Ponseti score, the feet were rated as good in four, fair in three and poor in nine. In seven feet avascular necrosis with collapse and flattening of the talar dome had occurred. In all of these feet the children were younger than ten years of age at the time of surgery. In three feet, avascular necrosis of the talar head was also observed. We conclude that osteotomy of the talar neck in children under the age of ten years can cause avascular necrosis and should be abandoned

Aims. Open reduction is required following failed conservative treatment of developmental dysplasia of the hip (DDH). The Ludloff medial approach is commonly used, but poor results have been reported, with rates of the development of avascular necrosis (AVN) varying between 8% and 54%. This retrospective cohort study evaluates the long-term radiographic and clinical outcome of dislocated hips treated using this approach. Patients and Methods. Children with a dislocated hip, younger than one year of age at the time of surgery, who were treated using a medial approach were eligible for the study. Radiographs were evaluated for the degree of dislocation and the presence of an ossific nucleus preoperatively, and for the degree of AVN and residual dysplasia at one and five years and at a mean of 12.7 years (4.6 to 20.8) postoperatively. Radiographic outcome was assessed using the Severin classification, after five years of age. Further surgical procedures were recorded. Functional outcome was assessed using the Pediatric Outcomes Data Collection Instrument (PODCI) or the Hip Disability and Osteoarthritis Outcome Score (HOOS), depending on the patient’s age. Results. A total of 52 children (58 hips) were included. At the latest follow-up, 11 hips (19%) showed signs of AVN. Further surgery was undertaken in 13 hips (22%). A total of 13 hips had a poor radiological outcome with Severin type III or higher. Of these, the age at the time of surgery was significantly higher (p < 0.05) than in those with a good Severin type (I or II). The patient-reported outcomes were significantly worse (p < 0.05) in children with a poor Severin classification. Conclusion. This retrospective long-term follow-up study shows that one in five children with DDH who undergo open reduction using a medial surgical approach has poor clinical and/or radiological outcome. The poor outcome is not related to the presence of AVN (19%), but due to residual dysplasia. Cite this article: Bone Joint J 2018;100-B:822–7

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.

Aims

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

Between January 1987 and December 1988 there were 7575 births in the Swansea maternity unit. Of these 823 (10.9%) were considered to be at ‘high risk’ for developmental dysplasia of the hip (DDH). Static ultrasound examination was performed in each case and the results classified on the basis of the method of Graf. A total of 117 type III–IV hips in 83 infants was splinted using the Aberdeen splint. Radiographs of these hips were taken at six and 12 months. Hilgenreiner’s measurements of the acetabular angle were made in all cases and the development of the femoral capital epiphysis was assessed by measuring the epiphyseal area. The effect of splintage on the acetabular angle and the epiphyseal area between the normal and abnormal splinted hips was compared. Radiographs of 16 normal infants (32 normal unsplinted hips) were used as a control group. This cohort has now been followed up for a minimum of nine years. There have been no complications as a result of splintage. The failure rate was 1.7% or 0.25 per 1000 live births. No statistical difference was found when comparing the effect of splintage on the acetabular angle and epiphyseal area between normal and abnormal splinted hips and normal unsplinted hips. Our study has shown that while the Aberdeen splint had a definite but small failure rate, it was safe in that it did not produce avascular necrosis. The current conventional view that a low rate of splintage is always best is therefore brought into question if the Aberdeen splint is chosen for the management of neonatal DDH

We present our early experience of arthroscopic reduction of the dislocated hip in very young infants with developmental dysplasia of the hip (DDH). Eight dislocated hips, which had failed attempts at closed reduction, were treated by arthroscopy of the hip in five children with a mean age of 5.8 months (4 to 7). A two-portal technique was used, with a medial sub-adductor portal for a 2.7 mm cannulated system with a 70° arthroscope and an anterolateral portal for the instruments. Following evaluation of the key intra-articular structures, the hypertrophic ligamentum teres and acetabular pulvinar were resected, and a limited release of the capsule was performed prior to reduction of the hip. All hips were reduced by a single arthroscopic procedure, the reduction being confirmed on MRI scan. None of the hips had an inverted labrum. The greatest obstacle to reduction was a constriction of the capsule. At a mean follow-up of 13.2 months (9 to 24), all eight hips remained stable. Three developed avascular necrosis. The mean acetabular index decreased from 35.5° (30° to 40°) pre-operatively to 23.3° (17° to 28°). This study demonstrates that arthroscopic reduction is feasible using two standardised portals. Longer follow-up studies are necessary to evaluate the functional results

Fractures of the femoral neck in children are rare, high-energy injuries with high complication rates. Their treatment has become more interventional but evidence of the efficacy of such measures is limited. We performed a systematic review of studies examining different types of treatment and their outcomes, including avascular necrosis (AVN), nonunion, coxa vara, premature physeal closure (PPC), and Ratliff’s clinical criteria. A total of 30 studies were included, comprising 935 patients. Operative treatment and open reduction were associated with higher rates of AVN. Delbet types I and II fractures were most likely to undergo open reduction and internal fixation. Coxa vara was reduced in the operative group, whereas nonunion and PPC were not related to surgical intervention. Nonunion and coxa vara were unaffected by the method of reduction. Capsular decompression had no effect on AVN. Although surgery allows a more anatomical union, it is uncertain whether operative treatment or the type of reduction affects the rate of AVN, nonunion or PPC, because more severe fractures were operated upon more frequently. A delay in treatment beyond 24 hours was associated with a higher incidence of AVN.

Cite this article: Bone Joint J 2013;95-B:135-41.

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. Methods. A qualitative study gathered information from children and their families affected by Perthes’ disease, along with treating clinicians. Interviews followed a coding framework, with the interview schedule informed by behavioural theory and patient and public involvement. Transcripts were analyzed using the framework method. Results. A total of 24 interviews took place, with 12 child/family dyads and 12 clinicians from UK NHS centres. Interviews identified widespread variation of routine care. Children/their families recounted positive experiences when included in the decision-making process for treatment. There is a strong desire from clinicians and children/families for consistent guidance from everyone involved in care, which should be based on clinical consensus. Conclusion. This is the first study to describe how children/families and clinicians experienced receiving or providing treatment in Perthes’ disease. The results indicate the need for robust evidence to support treatment decisions. Children and families valued feeling involved in the clinical decision-making process. Clinicians acknowledged the central importance of providing patient-centred care, particularly in the absence of robust evidence to guide the optimal treatment decisions. This study will inform a future Delphi project to develop clinical consensus guidelines for the treatment of Perthes’ disease. Cite this article: Bone Jt Open 2023;4(10):735–741

Aims. Brace treatment is the cornerstone of managing developmental dysplasia of the hip (DDH), yet there is a lack of evidence-based treatment protocols, which results in wide variations in practice. To resolve this, we have developed a comprehensive nonoperative treatment protocol conforming to published consensus principles, with well-defined a priori criteria for inclusion and successful treatment. Methods. This was a single-centre, prospective, longitudinal cohort study of a consecutive series of infants with ultrasound-confirmed DDH who underwent a comprehensive nonoperative brace management protocol in a unified multidisciplinary clinic between January 2012 and December 2016 with five-year follow-up radiographs. The radiological outcomes were acetabular index-lateral edge (AI-L), acetabular index-sourcil (AI-S), centre-edge angle (CEA), acetabular depth ratio (ADR), International Hip Dysplasia Institute (IHDI) grade, and evidence of avascular necrosis (AVN). At five years, each hip was classified as normal (< 1 SD), borderline dysplastic (1 to 2 SDs), or dysplastic (> 2 SDs) based on validated radiological norm-referenced values. Results. Of 993 infants assessed clinically and sonographically, 21% (212 infants, 354 abnormal hips) had DDH and were included. Of these, 95% (202 infants, 335 hips) successfully completed bracing, and 5% (ten infants, 19 hips) failed bracing due to irreducible hip(s). The success rate of bracing for unilateral dislocations was 88% (45/51 infants) and for bilateral dislocations 83% (20/24 infants). The femoral nerve palsy rate was 1% (2/212 infants). At five-year follow-up (mean 63 months (SD 5.9; 49 to 83)) the prevalence of residual dysplasia after successful brace treatment was 1.6% (5/312 hips). All hips were IHDI grade I and none had AVN. Four children (4/186; 2%) subsequently underwent surgery for residual dysplasia. Conclusion. Our comprehensive protocol for nonoperative treatment of infant DDH has shown high rates of success and extremely low rates of residual dysplasia at a mean age of five years. Cite this article: Bone Joint J 2023;105-B(8):935–942

Aims. To determine the likelihood of achieving a successful closed reduction (CR) of a dislocated hip in developmental dysplasia of the hip (DDH) after failed Pavlik harness treatment We report the rate of avascular necrosis (AVN) and the need for further surgical procedures. Methods. Data was obtained from the Northern Ireland DDH database. All children who underwent an attempted closed reduction between 2011 and 2016 were identified. Children with a dislocated hip that failed Pavlik harness treatment were included in the study. Successful closed reduction was defined as a hip that reduced in theatre and remained reduced. Most recent imaging was assessed for the presence of AVN using the Kalamchi and MacEwen classification. Results. There were 644 dislocated hips in 543 patients initially treated in Pavlik harness. In all, 67 hips failed Pavlik harness treatment and proceeded to arthrogram (CR) under general anaesthetic at an average age of 180 days. The number of hips that were deemed reduced in theatre was 46 of the 67 (69%). A total of 11 hips re-dislocated and underwent open reduction, giving a true successful CR rate of 52%. For the total cohort of 67 hips that went to theatre for arthrogram and attempted CR, five (7%) developed clinically significant AVN at an average follow-up of four years and one month, while none of the 35 hips whose reduction was truly successful developed clinically significant AVN. Conclusion. The likelihood of a successful closed reduction of a dislocated hip in the Northern Ireland population, which has failed Pavlik harness treatment, is 52% with a clinically significant AVN rate of 7%. As such, we continue to advocate closed reduction under general anaesthetic for the hip that has failed Pavlik harness. Cite this article: Bone Jt Open 2021;2(8):594–598

Aims. Osteonecrosis (ON) can cause considerable morbidity in young people who undergo treatment for acute lymphoblastic leukaemia (ALL). The aims of this study were to determine the operations undertaken for ON in this population in the UK, along with the timing of these operations and any sequential procedures that are used in different joints. We also explored the outcomes of those patients treated by core decompression (CD), and compared this with conservative management, in both the pre- or post-collapse stages of ON. Methods. UK treatment centres were contacted to obtain details regarding surgical interventions and long-term outcomes for patients who were treated for ALL and who developed ON in UKALL 2003 (the national leukaemia study which recruited patients aged 1 to 24 years at diagnosis of ALL between 2003 and 2011). Imaging of patients with ON affecting the femoral head was requested and was used to score all lesions, with subsequent imaging used to determine the final grade. Kaplan-Meier failure time plots were used to compare the use of CD with non surgical management. Results. Detailed information was received for 85 patients who had developed ON during the course of their ALL treatment. A total of 206 joints were affected by ON. Of all joints affected by ON, 21% required arthroplasty, and 43% of all hips affected went on to be replaced. CD was performed in 30% of hips affected by ON. The majority of the hips were grade 4 or 5 at initial diagnosis of ON. There was no significant difference in time to joint collapse between those joints in which CD was performed, compared with no joint-preserving surgical intervention. Conclusion. There is a high incidence of surgery in young people who have received treatment for ALL and who have developed ON. Our results suggest that CD of the femoral head in this group of patients does not delay or improve the rates of femoral head survival. Cite this article: Bone Joint J 2021;103-B(3):589–596

Aims

Fixation techniques used in the treatment of slipped capital femoral epiphysis (SCFE) that allow continued growth of the femoral neck, rather than inducing epiphyseal fusion in situ, have the advantage of allowing remodelling of the deformity. The aims of this study were threefold: to assess whether the Free-Gliding (FG) SCFE screw prevents further slip; to establish whether, in practice, it enables lengthening and gliding; and to determine whether the age of the patient influences the extent of glide.

Aims. Preserving growth following limb-salvage surgery of the upper limb in children remains a challenge. Vascularized autografts may provide rapid biological incorporation with the potential for growth and longevity. In this study, we aimed to describe the outcomes following proximal humeral reconstruction with a vascularized fibular epiphyseal transfer in children with a primary sarcoma of bone. We also aimed to quantify the hypertrophy of the graft and the annual growth, and to determine the functional outcomes of the neoglenofibular joint. Patients and Methods. We retrospectively analyzed 11 patients who underwent this procedure for a primary bone tumour of the proximal humerus between 2004 and 2015. Six had Ewing’s sarcoma and five had osteosarcoma. Their mean age at the time of surgery was five years (two to eight). The mean follow-up was 5.2 years (1 to 12.2). Results. The overall survival at five and ten years was 91% (confidence interval (CI) 95% 75% to 100%). At the time of the final review, ten patients were alive. One with local recurrence and metastasis died one-year post-operatively. Complications included seven fractures, four transient nerve palsies, and two patients developed avascular necrosis of the graft. All the fractures presented within the first postoperative year and united with conservative management. One patient had two further operations for a slipped fibular epiphysis of the autograft, and a hemi-epiphysiodesis for lateral tibial physeal arrest. Hypertrophy and axial growth were evident in nine patients who did not have avascular necrosis of the graft. The mean hypertrophy index was 65% (55% to 82%), and the mean growth was 4.6 mm per annum (2.4 to 7.6) in these nine grafts. At final follow-up, the mean modified functional Musculoskeletal Tumour Society score was 77% (63% to 83%) and the mean Toronto Extremity Salvage Score (TESS) was 84% (65% to 94%). Conclusion. Vascularized fibular epiphyseal transfer preserves function and growth in young children following excision of the proximal humerus for a malignant bone tumour. Function compares favourably to other limb-salvage procedures in children. Longer term analysis is required to determine if this technique proves to be durable into adulthood. Cite this article: Bone Joint J 2018;100-B:535–41

Between July 1994 and June 2004, 60 patients with 76 slipped upper femoral epiphyses were managed within the adult trauma service of three hospitals. Treatment was by a single cannulated screw. Of these cases, 53 were unilateral, in 17 of which uncomplicated prophylactic fixation of the contralateral hip was performed. Of the other 36 cases, nine presented with a subsequent slip despite ongoing out-patient care. The subsequent slip was unpredictable in timing and unrelated to the age at the initial slip. It was more often unstable and in one case avascular necrosis developed. The overall rate of avascular necrosis, although in accordance with the literature, was 60% in acute unstable slips with a slip angle greater than 40°. In our experience, prophylactic fixation was safer than continued observation of the contralateral hip

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We aimed to assess the cumulative risk of total hip arthroplasty (THA) from in situ fixation for slipped capital femoral epiphysis (SCFE) after a follow-up of almost 50 years.

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Developmental dysplasia of the hip (DDH) can be managed effectively with non-surgical interventions when diagnosed early. However, the likelihood of surgical intervention increases with a late presentation. Therefore, an effective screening programme is essential to prevent late diagnosis and reduce surgical morbidity in the population.

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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.

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We investigated the prevalence of late developmental dysplasia of the hip (DDH), abduction bracing treatment, and surgical procedures performed following the implementation of universal ultrasound screening versus selective ultrasound screening programmes.

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Accurate skeletal age and final adult height prediction methods in paediatric orthopaedics are crucial for determining optimal timing of growth-guiding interventions and minimizing complications in treatments of various conditions. This study aimed to evaluate the accuracy of final adult height predictions using the central peak height (CPH) method with long leg X-rays and four different multiplier tables.

We prospectively studied the benefits and risks of prolonged treatment with the Pavlik harness in infants with idiopathic developmental dysplasia of the hip. Bracing was continued as long as abduction improved. It was started at a mean age of four months (1 to 6.9). Outcome measures were the number of successful reductions, the time to reduction, the acetabular index and evidence of avascular necrosis at follow-up at one year. In 50 infants with 62 subluxated and dislocated hips (42 Graf type III and 20 type IV), 37 were reduced successfully with a mean time to reduction of 13.4 weeks (. sd. 6.8). Bracing was successful in 31 type-III (73.8%) and in only six type-IV hips (20%, p = 0.002). Avascular necrosis was seen in ten hips. Prolonged treatment with the Pavlik harness for developmental dysplasia of the hip over the age of one month can be beneficial in type-III hips, but it is unclear as to whether this is the optimal treatment, since it may postpone the need for closed or open reduction to a more unfavourable age. The use of the Pavlik harness in type-IV hips in this age group is questionable, but if used, prolonged bracing is not advised

Difficulties posed in managing developmental dysplasia of the hip diagnosed late include a high-placed femoral head, contracted soft tissues and a dysplastic acetabulum. A combination of open reduction with femoral shortening of untreated congenital dislocations is a well-established practice. Femoral shortening prevents excessive pressure on the located femoral head which can cause avascular necrosis. Instability due to a coexisting dysplastic shallow acetabulum is common, and so a pelvic osteotomy is performed to achieve a stable and concentric hip reduction. We retrospectively reviewed 15 patients (18 hips) presenting with developmental dysplasia of the hip aged four years and above who were treated by a one-stage combined procedure performed by the senior author. The mean age at operation was five years and nine months (4 years to 11 years). The mean follow-up was six years ten months (2 years and 8 months to 8 years and 8 months). All patients were followed up clinically and radiologically in accordance with McKay’s criteria and the modified Severin classification. According to the McKay criteria, 12 hips were rated excellent and six were good. All but one had a full range of movement. Eight had a limb-length discrepancy of about 1 cm. All were Trendelenburg negative. The modified Severin classification demonstrated four hips of grade IA, six of grade IB, and eight of grade II. One patient had avascular necrosis and one an early subluxation requiring revision. One-stage correction of congenital dislocation of the hip in an older child is a safe and effective treatment with good results in the short to medium term

Between June 2001 and November 2008 a modified Dunn osteotomy with a surgical hip dislocation was performed in 30 hips in 28 patients with slipped capital femoral epiphysis. Complications and clinical and radiological outcomes after a mean follow-up of 3.8 years (1.0 to 8.5) were documented. Subjective outcome was assessed using the Harris hip score and the Western Ontario and McMaster Universities osteoarthritis index questionnaire. Anatomical or near-anatomical reduction was achieved in all cases. The epiphysis in one hip showed no perfusion intra-operatively and developed avascular necrosis. There was an excellent outcome in 28 hips. Failure of the implants with a need for revision surgery occurred in four hips. Anatomical reduction can be achieved by this technique, with a low risk of avascular necrosis. Cautious follow-up is necessary in order to avoid implant failure

We analysed the incidence of avascular necrosis in 101 hips of 90 infants with congenital dislocation treated with the Pavlik harness and followed up for more than one year. Using ultrasonography in the flexed-abducted position the hips were classified as type A when the femoral head was displaced posteriorly, but within the socket and making contact with the posterior inner wall of the acetabulum; type B when it was in contact with the posterior margin of the acetabulum, with its centre at this level or anterior to it; and type C when it was displaced out of the socket, with its centre posterior to the posterior rim of the acetabulum. Eighty-seven hips were reduced by the harness (86%), and seven of these developed avascular necrosis (8%). All 69 hips with type-A dislocation were reduced, and only one (1.4%) showed slight avascular necrosis. Eighteen (78.3%) of 23 hips with type-B dislocation were reduced, and six developed avascular necrosis (33.3%). In one hip, the femoral head was severely damaged. None of the nine hips with type-C dislocation was reduced in the harness. We conclude that the Pavlik harness is indicated for type-A, but not for type-B or type-C dislocations

We have investigated whether early anatomical open reduction and internal fixation (ORIF) reduces the incidence of complications of fracture of the femoral neck in children, including avascular necrosis, compared with closed reduction and internal fixation (CRIF). We retrospectively reviewed 27 such fractures (15 type-II and 12 type-III displaced fractures) in children younger than 16 years of age seen in our hospital between February 1989 and March 2007. We divided the patients into three groups according to the quality of the reduction (anatomical, acceptable, and unacceptable) and the clinical results into two groups (satisfactory and unsatisfactory). Of the 15 fractures treated by ORIF, 14 (93.3%) had anatomical reduction and reduction was acceptable in one. Of the 12 treated by CRIF, three (25.0%) had anatomical reduction, eight had acceptable reduction (66.7%), and one (8.3%) unacceptable reduction. Of the 15 fractures treated by ORIF, 14 (93.3%) had a good result and one a fair result. Of the 12 treated by CRIF, seven (58.3%) had a good result, two (16.7%) a fair result and three (25.0%) a poor result. There were seven complications in five patients. ORIF gives better reduction with fewer complications, including avascular necrosis, than does CRIF in fractures of the femoral neck in children

Aims. Our aim was to assess the effectiveness of a protocol involving a standardised closed reduction for the treatment of children with developmental dysplasia of the hip (DDH) in maintaining reduction and to report the mid-term results. Methods. A total of 133 hips in 120 children aged less than two years who underwent closed reduction, with a minimum follow-up of five years or until subsequent surgery, were included in the study. The protocol defines the criteria for an acceptable reduction and the indications for a concomitant soft-tissue release. All children were immobilised in a short- leg cast for three months. Arthrograms were undertaken at the time of closed reduction and six weeks later. Follow-up radiographs were taken at six months and one, two and five years later and at the latest follow-up. The Tönnis grade, acetabular index, Severin grade and signs of osteonecrosis were recorded. Results. A total of 67 hips (51%) were Tönnis grade 3/4 hips. By 12 months, 20 reductions (15%) had not been maintained, and these required open reduction. In all, 55% of these were Severin 1; the others were Severin 2, due to minor acetabular dysplasia. Of the 113 successful closed reductions, 98 hips (87%) were Severin 1. Surgery for residual DDH was offered for ten hips. Osteonecrosis was seen in 32 hips (29%) but was transient in 28. In total, two children (1.5%) had severe osteonecrosis. Bilateral dislocations were significantly more likely to fail and most Tönnis 4 hips failed. Conclusion. Closed reduction, with concomitant adductor and psoas release when required and the use of a short leg plaster of Paris cast for three months, can produce good mid-term results in children with DDH aged less than two years. This protocol is not recommended for Tönnis 4 hips. Cite this article: Bone Joint J 2016;98-B:1548–53

The medial approach for the treatment of children with developmental dysplasia of the hip (DDH) in whom closed reduction has failed requires minimal access with negligible blood loss. In the United Kingdom, there is a preference for these children to be treated using an anterolateral approach after the appearance of the ossific nucleus. In this study we compared these two protocols, primarily for the risk of osteonecrosis. Data were gathered prospectively for protocols involving the medial approach (26 hips in 22 children) and the anterolateral approach (22 hips in 21 children) in children aged <  24 months at the time of surgery. Osteonecrosis of the femoral head was assessed with validated scores. The acetabular index (AI) and centre–edge angle (CEA) were also measured. . The mean age of the children at the time of surgery was 11 months (3 to 24) for the medial approach group and 18 months (12 to 24) for the anterolateral group, and the combined mean follow-up was 70 months (26 to 228). Osteonecrosis of the femoral head was evident or asphericity predicted in three of 26 hips (12%) in the medial approach group and four of 22 (18%) in the anterolateral group (p = 0.52). The mean improvement in AI was 8.8° (4° to 12°) and 7.9° (6° to 10°), respectively, at two years post-operatively (p = 0.18). There was no significant difference in CEA values of affected hips between the two groups. Children treated using an early medial approach did not have a higher risk of developing osteonecrosis at early to mid-term follow-up than those treated using a delayed anterolateral approach. The rates of acetabular remodelling were similar for both protocols. Cite this article: Bone Joint J 2014;96-B:406–13

We undertook a retrospective comparative study of all patients with an unstable slipped capital femoral epiphysis presenting to a single centre between 1998 and 2011. There were 45 patients (46 hips; mean age 12.6 years; 9 to 14); 16 hips underwent intracapsular cuneiform osteotomy and 30 underwent pinning in situ, with varying degrees of serendipitous reduction. No patient in the osteotomy group was lost to follow-up, which was undertaken at a mean of 28 months (11 to 48); four patients in the pinning in situ group were lost to follow-up, which occurred at a mean of 30 months (10 to 50). Avascular necrosis (AVN) occurred in four hips (25%) following osteotomy and in 11 (42%) following pinning in situ. AVN was not seen in five hips for which osteotomy was undertaken > 13 days after presentation. AVN occurred in four of ten (40%) hips undergoing emergency pinning in situ, compared with four of 15 (47%) undergoing non-emergency pinning. The rate of AVN was 67% (four of six) in those undergoing pinning on the second or third day after presentation. Pinning in situ following complete reduction led to AVN in four out of five cases (80%). In comparison, pinning in situ following incomplete reduction led to AVN in 7 of 21 cases (33%). The rate of development of AVN was significantly higher following pinning in situ with complete reduction than following intracapsular osteotomy (p = 0.048). Complete reduction was more frequent in those treated by emergency pinning and was strongly associated with AVN (p = 0.005). Non-emergency intracapsular osteotomy may have a protective effect on the epiphyseal vasculature and should be undertaken with a delay of at least two weeks. The place of emergency pinning in situ in these patients needs to be re-evaluated, possibly in favour of an emergency open procedure or delayed intracapsular osteotomy. Non-emergency pinning in situ should be undertaken after a delay of at least five days, with the greatest risk at two and three days after presentation. Intracapsular osteotomy should be undertaken after a delay of at least 14 days. In our experience, closed epiphyseal reduction is harmful. Cite this article: Bone Joint J 2015;97-B:412–19

We present our experience of the modified Dunn procedure in combination with a Ganz surgical dislocation of the hip to treat patients with severe slipped capital femoral epiphysis (SCFE). The aim was to prospectively investigate whether this technique is safe and reproducible. We assessed the degree of reduction, functional outcome, rate of complications, radiological changes and range of movement in the hip. There were 28 patients with a mean follow-up of 38.6 months (24 to 84). The lateral slip angle was corrected by a mean of 50.9° (95% confidence interval 44.3 to 57.5). The mean modified Harris hip score at the final follow-up was 89.1 (. sd. 9.0) and the mean Non-Arthritic Hip score was 91.3 (. sd. 9.0). Two patients had proven pre-existing avascular necrosis and two developed the condition post-operatively. There were no cases of nonunion, implant failure, infection, deep-vein thrombosis or heterotopic ossification. The range of movement at final follow-up was nearly normal. This study adds to the evidence that the technique of surgical dislocation and anatomical reduction is safe and reliable in patients with SCFE. Cite this article: Bone Joint J 2013;95-B:424–9

We describe our experience in the reduction of dislocation of the hip secondary to developmental dysplasia using ultrasound-guided gradual reduction using flexion and abduction continuous traction (FACT-R). During a period of 13 years we treated 208 Suzuki type B or C complete dislocations of the hip in 202 children with a mean age of four months (0 to 11). The mean follow-up was 9.1 years (five to 16). The rate of reduction was 99.0%. There were no recurrent dislocations, and the rate of avascular necrosis of the femoral head was 1.0%. The rate of secondary surgery for residual acetabular dysplasia was 19.2%, and this was significantly higher in those children in whom the initial treatment was delayed or if other previous treatments had failed (p = 0.00045). The duration of FACT-R was significantly longer in severe dislocations (p = 0.001) or if previous treatments had failed (p = 0.018). . This new method of treatment is effective and safe in these difficult cases and offers outcomes comparable to or better than those of standard methods. Cite this article: Bone Joint J 2015;97-B:405–11

Slipped upper femoral epiphysis (SUFE) is the most common hip disorder to affect adolescents. Controversy exists over the optimal treatment of severe slips, with a continuing debate between in situ fixation versus corrective surgery. We present our experience in a series of 57 patients presenting with severe unilateral SUFE (defined > 50°) managed with a subcapital cuneiform osteotomy. Between 2001 and 2011, 57 patients (35 male, 22 female) with a mean age of 13.1 years (9.6 to 20.3, SD 2.3) were referred to our tertiary referral institution with a severe slip. The affected limb was rested in slings and springs before corrective surgery which was performed via an anterior Smith-Petersen approach. Radiographic analysis confirmed an improvement in mean head–shaft slip angle from 53.8. o. (standard deviation (. sd) 3.2). pre-operatively to 9.1. o. (. sd. 3.1) post-operatively, with minimal associated femoral neck shortening. In total 50 (88%) patients were complication free at a mean follow-up of seven years (2.8 to 13.9 years, . sd. 3). Their mean Oxford hip score was 44 (37 to 48) and median visual analogue pain score was 0 out of 10 (interquartile range 0 to 4). A total of six patients (10.5%) developed avascular necrosis requiring further surgery and one (1.8%) patient developed chondrolysis but declined further intervention. . This is a technically demanding operation with variable outcomes reported in the literature. We have demonstrated good results in our tertiary centre. Cite this article: Bone Joint J 2015;97-B:1718–25

In this study we evaluated the results of midtarsal release and open reduction for the treatment of children with convex congenital foot (CCF) (vertical talus) and compared them with the published results of peritalar release. Between 1977 and 2009, a total of 22 children (31 feet) underwent this procedure. In 15 children (48%) the CCF was isolated and in the remainder it was not (seven with arthrogryposis, two with spinal dysraphism, one with a polymalformative syndrome and six with an undefined neurological disorder). Pre-operatively, the mean tibiotalar angle was 150.2° (106° to 175°) and the mean calcaneal pitch angle was -19.3° (-72° to 4°). The procedure included talonavicular and calcaneocuboid joint capsulotomies, lengthening of tendons of tibialis anterior and the extensors of the toes, allowing reduction of the midtarsal joints. Lengthening of the Achilles tendon was necessary in 23 feet (74%). The mean follow-up was 11 years (2 to 21). The results, as assessed by the Adelaar score, were good in 24 feet (77.4%), fair in six (19.3%) and poor in one foot (3.3%), with no difference between those with isolated CCF and those without. The mean American Orthopaedic Foot and Ankle Society midfoot score was 89.9 (54 to 100) and 77.8 (36 to 93) for those with isolated CCF and those without, respectively. At the final follow-up, the mean tibiotalar (120°; 90 to 152) and calcaneal pitch angles (4°; -13 to 22) had improved significantly (p < 0.0001). Dislocation of the talonavicular and calcaneocuboid joints was completely reduced in 22 (70.9%) and 29 (93.6%) of feet, respectively. Three children (five feet) underwent further surgery at a mean of 8.5 years post-operatively, three with pes planovalgus and two in whom the deformity had been undercorrected. No child developed avascular necrosis of the talus. Midtarsal joint release and open reduction is a satisfactory procedure, which may provide better results than peritalar release. Complications include the development of pes planovalgus and persistent dorsal subluxation of the talonavicular joint. Cite this article: Bone Joint J 2014;96-B:837–44

We treated 15 hips (15 patients) with developmental dysplasia by a single-stage combination of open reduction through a medial approach and innominate osteotomy. The mean age of the patients at the time of operation was 20 months (13 to 30). The mean follow-up period was 9.6 years (4 to 14). At the final follow-up, 14 hips were assessed clinically as excellent and one hip as good. Radiologically, ten hips were rated as class I, four as class II and one as class III according to the criteria of Severin. No avascular necrosis was seen. No patient required subsequent surgery. Our results indicate that satisfactory results can be obtained with the single-stage combination of open reduction by the medial approach and innominate osteotomy for developmental dysplasia of the hip in a selected group of children older than 12 months. To our knowledge, no similar combined technique has been previously reported

We present the results of treatment of developmental dysplasia of the hip in infancy with the Pavlik harness using a United Kingdom screening programme with ultrasound-guided supervision. Initially, 128 consecutive hips in 77 patients were reviewed over a 40-month period; 123 of these were finally included in the study. The mean age of the patients at the start of treatment was five weeks (1 to 12). All hips were examined clinically and monitored with ultrasound scanning. Failure of treatment was defined as an inability to maintain reduction with the harness. All hips diagnosed with dysplasia or subluxation but not dislocation were managed successfully in the harness. There were 43 dislocated hips, of which 39 were reducible, but six failed treatment in the harness. There were four dislocated but irreducible hips which all failed treatment in the harness. One hip appeared to be successfully treated in the harness but showed persistent radiological dysplasia at 12 and 24 months. Grade 1 avascular necrosis was identified radiologically in three patients at 12 months

The efficacy of traction before an attempted closed reduction for patients with developmental dislocation of the hip remains controversial. We treated 55 children (62 dislocations of the hip) by preliminary, prolonged traction for a mean of eight weeks. All were followed up for at least two years in order to observe the development of any avascular changes within the femoral head. Of the 55 children, 27 (31 dislocations) were followed up until they were over six years of age. Fifty-seven of the 62 hips (92%) showed a successful closed reduction. Only one had radiological evidence of avascular necrosis of the femoral head. Of the 31 hips which were followed up to over six years of age, 15 (48%) showed residual subluxation. Our method of prolonged preliminary traction leads to a high rate of successful closed reduction, a low incidence of avascular necrosis and a reduced need for secondary operations

We reviewed 33 patients (35 hips) after open reduction of congenital dislocation of the hip using Ludloff’s medial approach. The mean age at the time of operation was 14 months (5 to 29) and at the time of final follow-up 20.1 years (15 to 24) giving a mean duration of follow-up of 19.4 years (14 to 23). We evaluated the radiological results by the Severin classification and the extent of avascular necrosis using the criteria of Kalamchi. At the latest review 16 hips (45.7%) were in Severin groups I or II (acceptable results) and 19 (54.3%) in Severin groups III, IV or V (unacceptable results). There was evidence of avascular necrosis in 15 hips (42.9%). The radiological results began to become worse at about the age of ten years when type-II avascular changes presented. We conclude that Ludloff’s medial approach for open reduction is unsatisfactory for the treatment of congenital dislocation since about half of our patients required additional operations

We reviewed 98 children (133 hips) with developmental dysplasia of the hip who underwent arthrography immediately after closed reduction by overhead traction. We followed the patients to skeletal maturity to investigate whether soft-tissue interposition influences acetabular development and avascular necrosis over the long term. The shape of the limbus and the thickness of the soft-tissue interposition at the acetabular floor, as shown on arthrograms at the time of reduction, were not directly related to the final radiological results or to the incidence of avascular necrosis. Even if marked soft-tissue interposition was found on the initial arthrogram, spontaneous disappearance was noted in 71% up to the age of five years. The final radiological results showed no difference between those in which the interposition disappeared and those with none at the time of closed reduction. However, the requirement for secondary surgery at the age of five years was significantly higher in those with more than 3.5 mm of soft-tissue interposition. In the no-disappearance group (group C) further operation was necessary in 100% and the results were significantly worse at maturity according to Severin’s classification. We suggest that the indications for open reduction should not be based solely on the arthrographic findings at the time of closed reduction

The outcome of one-stage bilateral open reduction through a medial approach for the treatment of developmental dysplasia of the hip in children under 18 months was studied in 23 children, 18 girls and five boys. Their mean age at operation was 10.1 months (6 to 17) and the mean follow-up was 5.4 years (3 to 8). Acceptable clinical and radiological results were achieved in 44 (95.7%) and 43 (93.5%) of 46 hips, respectively. Excellent results were significantly evident in patients younger than 12 months, those who did not require acetabuloplasty, those whose ossific nucleus had appeared, and in those who did not develop avascular necrosis. One-stage bilateral medial open reduction avoids the need for separate procedures on the hips and has the advantages of accelerated management and shorter immobilisation and rehabilitation than staged operations

Fractures of the hip in children have been associated with a very high rate of serious complications including avascular necrosis (up to 47%) and coxa vara (up to 32%). Over a period of 20 years, we have treated displaced fractures by early anatomical reduction, internal fixation and immobilisation in a spica cast to try to reduce these complications. We have reviewed 18 patients who had a displaced non-pathological fracture of the hip when under 16 years of age. Their mean age at the time of the injury was eight years (2 to 13). They returned for examination and radiography at a mean follow-up of eight years (2 to 17). Each patient had been treated by early (″24 hours) closed or open reduction with internal fixation and 16 had immobilisation in a spica cast. By Delbet’s classification, there was one type-I, eight type-II, eight type-III, and one type-IV fractures. There were no complications in 15 patients. Avascular necrosis occurred in one patient (type-III), nonunion in one (type-II, one of the two patients who did not have a cast) and premature physeal closure in one (type-I). There were no cases of infection or complications as a result of the cast. Our treatment of displaced hip fractures in children by early reduction, internal fixation, and immobilisation in a spica cast gave reduced rates of complications compared with that of large published series in the literature

We reviewed prospectively, after skeletal maturity, a series of 24 patients (25 hips) with severe acute-on-chronic slipped capital femoral epiphysis which had been treated by subcapital cuneiform osteotomy. Patients were followed up for a mean of 8 years, 3 months (2 years, 5 months to 16 years, 4 months). Bedrest with ‘slings and springs’ had been used for a mean of 22 days (19 to 35) in 22 patients, and bedrest alone in two, before definitive surgery. The Iowa hip score, the Harris hip score and Boyer’s radiological classification for degenerative disease were used. The mean Iowa hip score at follow-up was 93.7 (69 to 100) and the mean Harris hip score 95.6 (78 to 100). Degenerative joint changes were graded as 0 in 19 hips, grade 1 in four and grade 2 in two. The rate of avascular necrosis was 12% (3 of 25) and the rate of chondrolysis was 16% (4 of 25). We conclude that after a period of bed rest with slings and springs for three weeks to gain stability, subcapital cuneiform osteotomy for severe acute-on-chronic slipped capital femoral epiphysis is a satisfactory method of treatment with an acceptable rate of complication

Aims

The objective of this study was to evaluate the clinical and radiological outcomes of patients younger than six months of age with developmental dysplasia of the hip (DDH) managed by either a Pavlik harness or Tübingen hip flexion splint.

Aims

Hip displacement, common in patients with cerebral palsy (CP), causes pain and hinders adequate care. Hip reconstructive surgery (HRS) is performed to treat hip displacement; however, only a few studies have quantitatively assessed femoral head sphericity after HRS. The aim of this study was to quantitatively assess improvement in hip sphericity after HRS in patients with CP.

We reviewed the medical records of 115 patients with 130 hips with developmental dysplasia with complete dislocation in the absence of a neuromuscular disorder, spontaneous reduction with a Pavlik harness, and a minimum of 14 years’ follow-up. The mean age at the time of harness application was 4.8 months (1 to 12) and the mean time spent in the harness was 6.1 months (3 to 12). A total of 108 hips (83.1%) were treated with the harness alone and supplementary surgery for residual acetabular dysplasia, as defined by an acetabular index > 30°, was performed in 22 hips (16.9%). An overall satisfactory outcome (Severin grade I or II) was achieved in 119 hips (91.5%) at a mean follow-up of 16 years (14 to 32) with a follow-up rate of 75%. Avascular necrosis of the femoral head was noted in 16 hips (12.3%), seven of which (44%) underwent supplementary surgery and nine (56%) of which were classified as satisfactory. The acetabular index was the most reliable predictor of residual acetabular dysplasia

This paper describes the technique and results of an acetabuloplasty in which the false acetabulum is turned down to augment the dysplastic true acetabulum at its most defective part. This operation was performed in 17 hips (16 children), with congenital dislocation and false acetabula. The mean age at operation was 5.1 years (4 to 8). The patients were followed clinically and radiologically for a mean of 6.3 years (5 to 10). A total of 16 hips had excellent results and there was one fair result due to avascular necrosis. The centre-edge angles and the obliquity of the acetabular roof improved in all cases, from a mean of −15.9° (−19° to 3°) and 42.6° (33° to 46°) to a mean of 29.5° (20° to 34°) and 11.9° (9° to 19°), respectively. The technique is not complex and is stable without internal fixation. It provides a near-normal acetabulum that requires minimal remodelling, and allows early mobilisation