Aims. Abduction bracing is commonly used to treat developmental dysplasia of the hip (DDH) following closed reduction and spica casting, with little evidence to support or refute this practice. The purpose of this study was to determine the efficacy of abduction bracing after closed reduction in improving acetabular index (AI) and reducing secondary surgery for residual hip dysplasia. Methods. We performed a retrospective review of patients treated with closed reduction for DDH at a single tertiary referral centre. Demographic data were obtained including severity of dislocation based on the International Hip Dysplasia Institute (IHDI) classification, age at reduction, and casting duration. Patients were prescribed no abduction bracing, part-time, or full-time wear post-reduction and casting. AI measurements were obtained immediately upon cast removal and from two- and four-year follow-up radiographs. Results. A total of 243 hips underwent closed reduction and 82% (199/243) were treated with abduction bracing. There was no difference between those treated with or without bracing with regard to sex, age at reduction, severity of dislocation, spica duration, or immediate post-casting AI (all p > 0.05). There was no difference in hips treated with or without abduction brace with regard to AI at two years post-reduction (32.4° (SD 5.3°) vs 30.9° (SD 4.6°), respectively; p = 0.099) or at four years post-reduction (26.4° (SD 5.2°) vs 25.4° (SD 5.1°), respectively; p = 0.231). Multivariate analysis revealed only IHDI grade predicted AI at two years post-reduction (p = 0.004). There was no difference in overall rate of secondary surgery for residual dysplasia between hips treated with or without bracing (32% vs 39%, respectively; p = 0.372). However, there was an increased risk of early secondary surgery (< two years post-reduction) in the non-braced group (11.4% vs 2.5%; p = 0.019). Conclusion. Abduction bracing following closed reduction for DDH treatment is not associated with decreased residual dysplasia at two or four years post-reduction but may reduce rates of early secondary surgery. A prospective study is indicated to provide more definitive recommendations. Cite this article: Bone Joint J 2023;105-B(12):1327–1332

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. The goal of closed reduction (CR) in the treatment of developmental dysplasia of the hip (DDH) is to achieve and maintain concentricity of the femoral head in the acetabulum. However, concentric reduction is not immediately attainable in all hips and it remains controversial to what degree a non-concentric reduction is acceptable. This prospective study is aimed at investigating the dynamic evolution of the hip joint space after CR in DDH using MRI. Methods. A consecutive series of patients with DDH who underwent CR since March 2014 were studied. Once the safety and stability were deemed adequate intraoperatively, reduction was accepted regardless of concentricity. Concentricity was defined when the superior joint space (SJS) and medial joint space (MJS) were both less than 2 mm, based on MRI. A total of 30 children, six boys and 24 girls, involving 35 hips, were recruited for the study. The mean age at CR was 13.7 months (3.5 to 27.6) and the mean follow-up was 49.5 months (approximately four years) (37 to 60). The joint space was evaluated along with the interval between the inverted and everted limbus. Results. Only three hips (8.6%) were fully concentric immediately after CR. During follow-up, 24 hips (68.6%) and 27 hips (77.1%) became concentric at six months and one year, respectively. Immediate SJS after CR decreased from 3.51 mm to 0.79 mm at six months follow-up (p = 0.001). SJS in the inverted group decreased from 3.75 mm to 0.97 mm at six months follow-up. SJS or MJS in the everted group were less than those in the inverted group at each time of follow-up (p = 0.008, p = 0.002). Conclusion. A stable, safe but non-concentric reduction achieved before the age of two years appears to improve over time with nearly 80% of hips becoming fully concentric by one year. Cite this article: Bone Joint J 2020;102-B(5):618–626

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 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 treated 22 children with a supracondylar fracture of the humerus and an ipsilateral fracture of the forearm by closed reduction and percutaneous fixation. There were four Gartland type-II and 18 Gartland type-III supracondylar fractures of the humerus. There were fractures of both bones of the forearm in 16 and of the radius in six. Both the supracondylar and the distal forearm fractures were treated by closed reduction and percutaneous fixation. The mean follow-up time was 38.6 months. At the latest follow-up there were 21 excellent or good results and one fair result. There were no cases of delayed union, nonunion or malunion. Five nerve injuries were diagnosed on admission and all recovered spontaneously within eight weeks. No patient developed a compartment syndrome

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

Aims. We aimed to evaluate the health-related quality of life (HRQoL) in children with supracondylar humeral fractures (SCHFs), who were treated following the recommendations of the Paediatric Comprehensive AO Classification, and to assess if HRQoL was associated with AO fracture classification, or fixation with a lateral external fixator compared with closed reduction and percutaneous pinning (CRPP). Methods. We were able to follow-up on 775 patients (395 girls, 380 boys) who sustained a SCHF from 2004 to 2017. Patients completed questionnaires including the Quick Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH; primary outcome), and the Pediatric Quality of Life Inventory (PedsQL). Results. An AO type I SCHF was most frequent (327 children; type II: 143; type III: 150; type IV: 155 children). All children with type I fractures were treated nonoperatively. Two children with a type II fracture, 136 with a type III fracture, and 141 children with a type IV fracture underwent CRPP. In the remaining 27 children with type III or IV fractures, a lateral external fixator was necessary for closed reduction. There were no open reductions. After a mean follow-up of 6.3 years (SD 3.7), patients with a type I fracture had a mean QuickDASH of 2.0 (SD 5.2), at a scale of 0 to 100, with lower values representing better HRQoL (type II: 2.8 (SD 10.7); type III: 3.3 (SD 8.0); type IV: 1.8 (SD 4.6)). The mean function score of the PedsQL ranged from 97.4 (SD 8.0) for type I to 96.1 (SD 9.1) for type III fractures, at a scale of 0 to 100, with higher values representing better HRQoL. Conclusion. In this cohort of 775 patients in whom nonoperative treatment was chosen for AO type I and II fractures and CRPP or a lateral external fixator was used in AO type III and IV fractures, there was equally excellent mid- and long-term HRQoL when assessed by the QuickDASH and PedsQL. These results indicate that the treatment protocol followed in this study is unambiguous, avoids open reductions, and is associated with excellent treatment outcomes. Cite this article: Bone Joint J 2020;102-B(6):755–765

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. Open reduction in developmental dysplasia of the hip (DDH) is regularly performed despite screening programmes, due to failure of treatment or late presentation. A protocol for open reduction of DDH has been refined through collaboration between surgical, anaesthetic, and nursing teams to allow same day discharge. The objective of this study was to determine the safety and feasibility of performing open reduction of DDH as a day case. Methods. A prospectively collected departmental database was visited. All consecutive surgical cases of DDH between June 2015 and March 2020 were collected. Closed reductions, bilateral cases, cases requiring corrective osteotomy, and children with comorbidities were excluded. Data collected included demographics, safety outcome measures (blood loss, complications, readmission, reduction confirmation), and feasibility for discharge according to the Face Legs Activity Cry Consolidability (FLACC) pain scale. A satisfaction questionnaire was filled by the carers. Descriptive statistics were used for analysis. Results. Out of 168 consecutive DDH cases, 16 patients fit the inclusion criteria (age range 10 to 26 months, 13 female). Intraoperative blood loss ranged from "minimal" to 120 ml, and there were no complications or readmissions. The FLACC score was 0 for all patients. The carers satisfaction questionnaire expressed high satisfaction from the experience with adequate information and support provided. Conclusion. Open reduction in DDH, without corrective osteotomy, is safe and feasible to be managed as a day case procedure. It requires a clear treatment pathway, analgesia, sufficient counselling, and communication with carers. It is even more important during the COVID-19 pandemic when reduced length of hospital stay is likely to be safer for both patient and their parents. Cite this article: Bone Joint Open 2021;2(4):271–277

Aims. The significance of the ‘clicky hip’ in neonatal and infant examination remains controversial with recent conflicting papers reigniting the debate. We aimed to quantify rates of developmental dysplasia of the hip (DDH) in babies referred with ‘clicky hips’ to our dedicated DDH clinic. Patients and Methods. A three-year prospective cohort study was undertaken between 2014 and 2016 assessing the diagnosis and treatment outcomes of all children referred specifically with ‘clicky hips’ as the primary reason for referral to our dedicated DDH clinic. Depending on their age, they were all imaged with either ultrasound scan or radiographs. Results. There were 69 ‘clicky hip’ referrals over the three-year period. This represented 26.9% of the total 257 referrals received in that time. The mean age at presentation was 13.6 weeks (1 to 84). A total of 19 children (28%) referred as ‘clicky hips’ were noted to have hip abnormalities on ultrasound scan, including 15 with Graf Type II hips (7 bilateral), one Graf Type III hip, and three Graf Type IV hips. Of these, ten children were treated with a Pavlik harness, with two requiring subsequent closed reduction in theatre; one child was treated primarily with a closed reduction and adductor tenotomy. In total, 11 (15.9%) of the 69 ‘clicky hip’ referrals required intervention with either harness or surgery. Conclusion. Our study provides further evidence that the ‘clicky hip’ referral can represent an underlying diagnosis of DDH and should, in our opinion, always lead to further clinical and radiological assessment. In the absence of universal ultrasound screening, we would encourage individual units to carefully assess their own outcomes and protocols for ‘clicky hip’ referrals and tailor ongoing service provision to local populations and local referral practices. Cite this article: Bone Joint J 2018;100-B:1249–52

Aims. Current American Academy of Orthopaedic Surgeons (AAOS) guidelines for treating femoral fractures in children aged two to six years recommend early spica casting although some individuals have recommended intramedullary stabilization in this age group. The purpose of this study was to compare the treatment and family burden of care of spica casting and flexible intramedullary nailing in this age group. Methods. Patients aged two to six years old with acute, non-pathological femur fractures were prospectively enrolled at one of three tertiary children’s hospitals. Either early closed reduction with spica cast application or flexible intramedullary nailing was accomplished under general anaesthesia. The treatment method was selected after discussion of the options by the surgeon with the family. Data were prospectively collected on patient demographics, fracture characteristics, complications, pain medication, and union. The Impact on Family Scale was obtained at the six-week follow-up visit. In all, 75 patients were included in the study: 39 in the spica group and 36 in the nailing group. The mean age of the spica group was 2.71 (2.0 to 6.9) years and the mean age of the nailing group was 3.16 (2.0 to 6.9) years. Results. All fractures healed without evidence of malunion or more than 2.0 cm of shortening. The mean Impact on Family score was 70.2 for the spica group and 63.2 (55 to 99) for the nailing group, a statistically significant difference (p = 0.024) in a univariate analysis suggesting less impairment of the family in the intramedullary nailing group. There was no significant difference between pain medication requirements in the first 24 hours postoperatively. Two patients in the spica group and one patient in the intramedullary nailing group required additional treatment under anaesthesia. Conclusion. Both early spica casting and intramedullary nailing were effective methods for treating femoral fractures in children two to six years of age. Intramedullary stabilization provides an option in this age group that may be advantageous in some social situations that depend on the child’s mobility. Fracture treatment should be individualized based on factors that extend beyond anatomical and biological factors. Cite this article: Bone Joint J 2020;102-B(8):1056–1061

Aims. The purpose of this study was to analyze the incidence of the different ultrasound phenotypes of developmental dysplasia of the hip (DDH), and to determine their subsequent course. Patients and Methods. A consecutive series of 28 092 neonates was screened and classified according to the Graf method as part of a nationwide surveillance programme, and then followed prospectively. Abnormal hips were followed until they became normal (Graf type I). Type IIb hips and higher grades were treated by abduction in a Tübinger orthosis until normal. Dislocated hips underwent closed or open reduction. Results. Overall, 90.2% of hips were normal at birth. Type IIa hips (8.9%) became normal at a median of six weeks (interquartile range (IQR) 6 to 9). Type IIc and IId hips (0.67%) became normal after ten weeks (IQR 7 to 13). There were 19 type lll and eight type lV hips at baseline. There were 24 closed reductions and one open reduction. No late presentations of DDH were detected within the first five years of life. Conclusion. The incidence of DDH was eight per 1000 live births. The treatment rate was 1% (n = 273). The rate of first operations on the newborn hip was 0.86, and rate of open surgery was 0.04. The cumulative rate of open surgery was 0.07. The authors take the view that early identification and treatment in abduction of all dysplastic hips in early childhood reduces the rate of open reduction and secondary DDH-related surgery later in life. Cite this article: Bone Joint J 2018;100-B:1399–1404

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

A retrospective study was performed in 100 children aged between two and 16 years, with a dorsally angulated stable fracture of the distal radius or forearm, who were treated with manipulation in the emergency department (ED) using intranasal diamorphine and 50% oxygen and nitrous oxide. Pre- and post-manipulation radiographs, the final radiographs and the clinical notes were reviewed. A successful reduction was achieved in 90 fractures (90%) and only three children (3%) required remanipulation and Kirschner wire fixation or internal fixation. The use of Entonox and intranasal diamorphine is safe and effective for the closed reduction of a stable paediatric fracture of the distal radius and forearm in the ED. . By facilitating discharge on the same day, there is a substantial cost benefit to families and the NHS and we recommend this method. Take home message: Simple easily reducible fractures of the distal radius and forearm in children can be successfully and safely treated in the ED using this approach, thus avoiding theatre admission and costly hospital stay. . Cite this article: Bone Joint J 2016;97-B:131–6

Retrosternal displacement of the medial aspect of the clavicle after physeal fracture is rare. We treated six patients with this injury between 1995 and 1998, all as an emergency in order to avoid complications associated with compression of adjacent mediastinal structures. Attempted closed reduction was undertaken, but all required open reduction and internal fixation using a wire suture. There were no associated complications. Five were reviewed clinically and radiologically at a minimum of one year after operation. All had regained full use of the affected arm without pain and had resumed their preinjury level of activity including sports. Follow-up radiographs showed union in the anatomical position in all patients. We recommend attempted closed reduction in the operating room, followed, if necessary, by open reduction. Internal fixation after open reduction gives stable fixation with minimal morbidity

The treatment of fractures of the neck of the radius in children is difficult, particularly if the angulation of the fracture exceeds 60°. Since 1994 we have used closed reduction and stabilisation with an intramedullary Kirschner wire in patients with grade-IV fractures according to the classification of Judet et al. In a retrospective analysis of a two-year period (1994 to 1996), 324 children with fractures of the elbow were treated in our department. Of these, 29 (9%) had a fracture of the neck of the radius; six were grade-IV injuries (1.9%). Five of the latter had an excellent postoperative result with normal movement of the elbow and forearm. One patient with a poor result had a concomitant dislocation of the elbow. Our results suggest that closed reduction and intramedullary pinning of grade-IV fractures allows adequate stabilisation while healing occurs

Fractures of the forearm (radius or ulna or both) in children have traditionally been immobilised in plaster of Paris (POP) but synthetic cast materials are becoming more popular. There have been no randomised studies comparing the efficacy of these two materials. The aim of this study was to investigate which cast material is superior for the management of these fractures. We undertook a single-centre prospective randomised trial involving 199 patients with acute fractures of the forearm requiring general anaesthesia for reduction. Patients were randomised by sealed envelope into either a POP or synthetic group and then underwent routine closed reduction and immobilisation in a cast. The patients were reviewed at one and six weeks. A satisfaction questionnaire was completed following the removal of the cast. All clinical complications were recorded and the cast indices were calculated. There was an increase in complications in the POP group. These complications included soft areas of POP requiring revision and loss of reduction with some requiring re-manipulation. There was an increased mean padding index in the fractures that lost reduction. Synthetic casts were preferred by the patients. This study indicates that the clinical outcomes and patient satisfaction are superior using synthetic casts with no reduction in safety. Cite this article: Bone Joint J 2013;95-B:1285–9

We report the results of 116 consecutive displaced extension supracondylar fractures of the elbow in children treated during the first two years after the introduction of the following protocol; closed reduction under general anaesthesia with fluoroscopic control and lateral percutaneous pinning using two parallel pins or, when closed reduction failed, open reduction and internal fixation by cross-pinning. Eight patients were lost to follow-up during the first postoperative year. The mean follow-up for the remaining 108 was 27.9 months (12 to 47, median 26.5). At the final follow-up, using Flynn’s overall modified classification, the clinical result was considered to be excellent in 99 patients (91.6%), good in five (4.6%) and poor in four (3.7%). All the poor results were due to a poor cosmetic result, but had good or excellent function. Technical error in the initial management of these four cases was thought to be the cause of the poor results. The protocol described resulted in good or excellent results in 96% of our patients, providing a safe and efficient treatment for displaced supracondylar fractures of the humerus even in less experienced hands

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