Aims. The aim of this study was to evaluate the epidemiology and treatment of Perthes’ disease of the hip. Methods. This was an anonymized comprehensive cohort study of Perthes’ disease, with a nested consented cohort. A total of 143 of 144 hospitals treating children’s hip disease in the UK participated over an 18-month period. Cases were cross-checked using a secondary independent reporting network of trainee surgeons to minimize those missing. Clinician-reported outcomes were collected until two years. Patient-reported outcome measures (PROMs) were collected for a subset of participants. Results. Overall, 371 children (396 hips) were newly affected by Perthes’ disease arising from 63 hospitals, with a median of two patients (interquartile range 1.0 to 5.5) per hospital. The annual incidence was 2.48 patients (95% confidence interval (CI) 2.20 to 2.76) per 100,000 zero- to 14-year-olds. Of these, 117 hips (36.4%) were treated surgically. There was considerable variation in the treatment strategy, and an optimized decision tree identified joint stiffness and age above eight years as the key determinants for containment surgery. A total of 348 hips (88.5%) had outcomes to two years, of which 227 were in the late reossification stage for which a hip shape outcome (Stulberg grade) was assigned. The independent predictors of a poorer radiological outcome were female sex (odds ratio (OR) 2.27 (95% CI 1.19 to 4.35)), age above six years (OR 2.62 (95% CI (1.30 to 5.28)), and over 50% radiological collapse at inclusion (OR 2.19 (95% CI 0.99 to 4.83)). Surgery had no effect on radiological outcomes (OR 1.03 (95% CI 0.55 to 1.96)). PROMs indicated the marked effect of the disease on the child, which persisted at two years. Conclusion. Despite the frequency of containment surgery, we found no evidence of improved outcomes. There appears to be a sufficient case volume and community equipoise among surgeons to embark on a randomized clinical trial to definitively investigate the effectiveness of containment surgery. Cite this article: Bone Joint J 2022;104-B(4):510–518

Aims. Ganz’s studies made it possible to address joint deformities on both the femoral and acetabular side brought about by Perthes’ disease. Femoral head reduction osteotomy (FHRO) was developed to improve joint congruency, along with periacetabular osteotomy (PAO), which may enhance coverage and containment. The purpose of this study is to show the clinical and morphological outcomes of the technique and the use of an implemented planning approach. Methods. From September 2015 to December 2021, 13 FHROs were performed on 11 patients for Perthes’ disease in two centres. Of these, 11 hips had an associated PAO. A specific CT- and MRI-based protocol for virtual simulation of the corrections was developed. Outcomes were assessed with radiological parameters (sphericity index, extrusion index, integrity of the Shenton’s line, lateral centre-edge angle (LCEA), Tönnis angle), and clinical parameters (range of motion, visual analogue scale (VAS) for pain, Merle d'Aubigné-Postel score, modified Harris Hip Score (mHHS), and EuroQol five-dimension five-level health questionnaire (EQ-5D-5L)). Early and late complications were reported. Results. The mean follow-up was 39.7 months (standard deviation (SD) 26.4). The mean age at surgery was 11.4 years (SD 1.6). No major complications were recorded. One patient required a total hip arthroplasty. Mean femoral head sphericity increased from 46.8% (SD 9.34%) to 70.2% (SD 15.44; p < 0.001); mean LCEA from 19.2° (SD 9.03°) to 44° (SD 10.27°; p < 0.001); mean extrusion index from 37.8 (SD 8.70) to 7.5 (SD 9.28; p < 0.001); and mean Tönnis angle from 16.5° (SD 12.35°) to 4.8° (SD 4.05°; p = 0.100). The mean VAS improved from 3.55 (SD 3.05) to 1.22 (1.72; p = 0.06); mean Merle d’Aubigné-Postel score from 14.55 (SD 1.74) to 16 (SD 1.6; p = 0.01); and mean mHHS from 60.6 (SD 18.06) to 81 (SD 6.63; p = 0.021). The EQ-5D-5L also showed significant improvements. Conclusion. FHRO associated with periacetabular procedures is a safe technique that showed improved functional, clinical, and morphological outcomes in Perthes’ disease. The newly introduced simulation and planning algorithm may help to further refine the technique. Cite this article: Bone Joint J 2024;106-B(5 Supple B):40–46

Aims. Perthes’ disease is an uncommon hip disorder with limited data on the long-term outcomes in adulthood. We partnered with community-based foundations and utilized web-based survey methodology to develop the Adult Perthes Survey, which includes demographics, childhood and adult Perthes’ disease history, the University of California Los Angeles (UCLA) Activity Scale item, Short Form-36, the Hip disability and Osteoarthritis Outcome Score, and a body pain diagram. Here we investigate the following questions: 1) what is the feasibility of obtaining > 1,000 survey responses from adults who had Perthes’ disease using a web-based platform?; and 2) what are the baseline characteristics and demographic composition of our sample?. Methods. The survey link was available publicly for 15 months and advertised among support groups. Of 1,505 participants who attempted the Adult Perthes survey, 1,182 completed it with a median timeframe of 11 minutes (IQR 8.633 to 14.72). Participants who dropped out were similar to those who completed the survey on several fixed variables. Participants represented 45 countries including the USA (n = 570; 48%), UK (n = 295; 25%), Australia (n = 133; 11%), and Canada (n = 46; 4%). Of the 1,182 respondents, 58% were female and the mean age was 39 years (SD 12.6). Results. Ages at onset of Perthes’ disease were < six years (n = 512; 43%), six to seven years (n = 321; 27%), eight to 11 years (n = 261; 22%), and > 11 years (n = 76; 6%), similar to the known age distribution of Perthes’ disease. During childhood, 40% (n = 476) of respondents had at least one surgery. Bracing, weightbearing restriction, and absence of any treatment varied significantly between USA and non-USA respondents (p < 0.001, p = 0.002, and p < 0.001, respectively). As adults, 22% (n = 261) had at least one total hip arthroplasty, and 30% (n = 347) had any type of surgery; both more commonly reported among women (p = 0.002). Conclusion. While there are limitations due to self-sampling, our study shows the feasibility of obtaining a large set of patient-reported data from adults who had childhood Perthes’ from multiple countries. Cite this article: Bone Jt Open 2022;3(5):404–414

Aims. Avascular femoral head necrosis in the context of gymnastics is a rare but serious complication, appearing similar to Perthes’ disease but occurring later during adolescence. Based on 3D CT animations, we propose repetitive impact between the main supplying vessels on the posterolateral femoral neck and the posterior acetabular wall in hyperextension and external rotation as a possible cause of direct vascular damage, and subsequent femoral head necrosis in three adolescent female gymnasts we are reporting on. Methods. Outcome of hip-preserving head reduction osteotomy combined with periacetabular osteotomy was good in one and moderate in the other up to three years after surgery; based on the pronounced hip destruction, the third received initially a total hip arthroplasty. Results. The described pathology is quite devastating, and extensive joint preserving surgery (which has been shown successful in Perthes’ cases) was less successful in this patient cohort. Conclusion. Supraselective angiography may be helpful to improve pathomechanical understanding and surgical decision making. Cite this article: Bone Jt Open 2022;3(9):666–673

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. Methods. A two-round, modified Delphi study was conducted online. An advisory group of children’s orthopaedic specialists consisting of physiotherapists, surgeons, and clinical nurse specialists designed a survey. In the first round, participants also had the opportunity to suggest new statements. The survey included statements related to ‘Exercises’, ‘Physical activity’, ‘Education/information sharing’, ‘Input from other services’, and ‘Monitoring assessments’. The survey was shared with clinicians who regularly treat children with Perthes’ disease in the UK using clinically relevant specialist groups and social media. A predetermined threshold of ≥ 75% for consensus was used for recommendation, with a threshold of between 70% and 75% being considered as ‘points to consider’. Results. A total of 40 participants took part in the first round, of whom 31 completed the second round. A total of 87 statements were generated by the advisory group and included in the first round, at the end of which 31 achieved consensus and were removed from the survey, and an additional four statements were generated. A total of 60 statements were included in the second round and 45 achieved the threshold for consensus from both rounds, with three achieving the threshold for ‘points to consider’. The recommendations predominantly included self-management, particularly relating to advice about exercise and education for children with Perthes’ disease and their families. Conclusion. Children’s orthopaedic specialists have reached consensus on recommendations for non-surgical treatment in Perthes’ disease. These statements will support decisions made in clinical practice and act as a foundation to support clinicians in the absence of robust evidence. The dissemination of these findings and the best way of delivering this care needs careful consideration, which we will continue to explore. Cite this article: Bone Joint J 2024;106-B(5):501–507

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. To identify a suite of the key physical, emotional, and social outcomes to be employed in clinical practice and research concerning Perthes' disease in children. Methods. The study follows the guidelines of the COMET-Initiative (Core Outcome Measures in Effectiveness Trials). A systematic review of the literature was performed to identify a list of outcomes reported in previous studies, which was supplemented by a qualitative study exploring the experiences of families affected by Perthes’ disease. Collectively, these outcomes formed the basis of a Delphi survey (two rounds), where 18 patients with Perthes’ disease, 46 parents, and 36 orthopaedic surgeons rated each outcome for importance. The International Perthes Study Group (IPSG) (Dallas, Texas, USA (October 2018)) discussed outcomes that failed to reach any consensus (either ‘in’ or ‘out’) before a final consensus meeting with representatives of surgeons, patients, and parents. Results. In total, 23 different outcome domains were identified from the systematic review, and a further ten from qualitative interviews. After round one of the Delphi survey, participants suggested five further outcome domains. A total of 38 outcomes were scored in round two of the Delphi. Among these, 16 outcomes were scored over the prespecified 70% threshold for importance (divided into six main categories: adverse events; life impact; resource use; pathophysiological manifestations; death; and technical considerations). Following the final consensus meeting, 14 outcomes were included in the final Core Outcome Set (COS). Conclusion. Core Outcome Sets (COSs) are important to improve standardization of outcomes in clinical research and to aid communication between patients, clinicians, and funding bodies. The results of this study should be a catalyst to develop high-quality clinical research in order to determine the optimal treatments for children with Perthes’ disease. Cite this article: Bone Joint J 2020;102-B(5):611–617

Aims. This study aimed to evaluate the relationship between hip shape and mid-term function in Perthes’ disease. It also explored whether the modified three-group Stulberg classification can offer similar prognostic information to the five-group system. Methods. A total of 136 individuals aged 12 years or older who had Perthes’ disease in childhood completed the Patient-Reported Outcomes Measurement Information System (PROMIS) Mobility score (function), Nonarthritic Hip Score (NAHS) (function), EuroQol five-dimension five-level questionnaire (EQ-5D-5L) score (quality of life), and the numeric rating scale for pain (NRS). The Stulberg class of the participants’ hip radiographs were evaluated by three fellowship-trained paediatric orthopaedic surgeons. Hip shape and Stulberg class were compared to PROM scores. Results. A spherical hip was associated with the highest function and quality of life, and lowest pain. Conversely, aspherical hips exhibited the lowest functional scores and highest pain. The association between worsening Stulberg class (i.e. greater deviation from sphericity) and worse outcome persisted after adjustment for age and sex in relation to PROMIS (predicted mean difference -1.77 (95% confidence interval (CI) -2.70 to -0.83)), NAHS (-5.68 (95% CI -8.45 to -2.90)), and NRS (0.61 (95% CI 0.14 to 1.08)), but not EQ-5D-5L (-0.03 (95% CI -0.72 to 0.11)). Conclusion. Patient-reported outcomes identify lower function, quality of life, and higher pain in aspherical hips. The magnitude of symptoms deteriorated with time. Hip sphericity (i.e. the modified three-group classification of spherical, oval, and aspherical) appeared to offer similar levels of detail to the five-group Stulberg classification. Cite this article: Bone Joint J 2023;105-B(6):711–716

Aims. Perthes’ disease is a condition which leads to necrosis of the femoral head. It is most commonly reported in children aged four to nine years, with recent statistics suggesting it affects around five per 100,000 children in the UK. Current treatment for the condition aims to maintain the best possible environment for the disease process to run its natural course. Management typically includes physiotherapy with or without surgical intervention. Physiotherapy intervention often will include strengthening/stretching programmes, exercise/activity advice, and, in some centres, will include intervention, such as hydrotherapy. There is significant variation in care with no consensus on which treatment option is best. The importance of work in this area has been demonstrated by the British Society for Children’s Orthopaedic Surgery through the James Lind Alliance’s prioritization of work to determine/identify surgical versus non-surgical management of Perthes’ disease. It was identified as the fourth-highest priority for paediatric lower limb surgery research in 2018. Methods. Five UK NHS centres, including those from the NEWS (North, East, West and South Yorkshire) orthopaedic group, contributed to this case review, with each entre providing clinical data from a minimum of five children. Information regarding both orthopaedic and physiotherapeutic management over a two-year post-diagnosis period was reviewed. Results. Data were extracted from the clinical records of 32 children diagnosed with Perthes’ disease; seven boys and 25 girls. The mean age of the children at diagnosis was 6.16 years (standard deviation (SD) 3.001). In all, 26 children were referred for physiotherapy. In the two-year period following diagnosis, children were seen a median of 7.5 times (interquartile range (IQR) 4.25 to 11) by an orthopaedic surgeon, and a median of 9.5 times (IQR 8 to 18.25) by a physiotherapist. One centre had operated on all of their children, while another had operated on none. Overall, 17 (53%) of the children were managed conservatively in the two-year follow-up period, and 15 (47%) of the children underwent surgery in the two-year follow-up period. Conclusion. The results of this case review demonstrate a variation of care provided to children in the UK with Perthes’ disease. Further national and international understanding of current care is required to underpin the rationale for different treatment options in children with Perthes’ disease. Cite this article: Bone Joint Open 2020;1-11:691–695

Aims. Perthes’ disease is a condition leading to necrosis of the femoral head. It is most common in children aged four to nine years, affecting around one per 1,200 children in the UK. Management typically includes non-surgical treatment options, such as physiotherapy with/without surgical intervention. However, there is significant variation in care with no consensus on the most effective treatment option. Methods. This systematic review aims to evaluate the effectiveness of non-surgical interventions for the treatment of Perthes’ disease. Comparative studies (experimental or observational) of any non-surgical intervention compared directly with any alternative intervention (surgical, non-surgical or no intervention) were identified from: Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), EMcare, Allied and Complementary Medicine Database (AMED), and the Physiotherapy Evidence Database (PEDro). Data were extracted on interventions compared and methodological quality. For post-intervention primary outcome of radiological scores (Stulberg and/or Mose), event rates for poor scores were calculated with significance values. Secondary outcomes included functional measures, such as range of movement, and patient-reported outcomes such as health-related quality of life. Results. In all, 15 studies (1,745 participants) were eligible for inclusion: eight prospective cohort studies, seven retrospective cohort studies, and no randomized controlled trials were identified. Non-surgical interventions largely focused on orthotic management (14/15 studies) and physical interventions such as muscle strengthening or stretching (5/15 studies). Most studies were of high/unknown risk of bias, and the range of patient outcomes was very limited, as was reporting of treatment protocols. Similar proportions of children achieving poor radiological outcomes were found for orthotic management and physical interventions, such as physiotherapy or weightbearing alteration, compared with surgical interventions or no intervention. Conclusion. Evidence from non-randomized studies found no robust evidence regarding the most effective non-surgical interventions for the treatment of children with Perthes’ disease. Future research, employing randomized trial designs, and reporting a wider range of patient outcomes is urgently needed to inform clinical practice. Cite this article: Bone Jt Open 2020;1-12:720–730

Aims. The aim of this study was to assess the prognostic value of the modified three-group Stulberg classification, which is based on the sphericity of the femoral head, in patients with Perthes’ disease. Methods. A total of 88 patients were followed from the time of diagnosis until a mean follow-up of 21 years. Anteroposterior pelvic and frog-leg lateral radiographs were obtained at diagnosis and at follow-up of one, five, and 21 years. At the five- and 21-year follow-up, the femoral heads were classified using a modified three-group Stulberg classification (round, ovoid, or flat femoral head). Further radiological endpoints at long-term follow-up were osteoarthritis (OA) of the hip and the requirement for total hip arthroplasty (THA). Results. There were 71 males (81%) and 17 females. A total of 13 patients had bilateral Perthes’ disease; thus 101 hips were analyzed. At five-year follow-up, 37 hips were round, 38 ovoid, and 26 flat. At that time, 66 hips (65%) were healed and 91 (90%) were skeletally immature. At long-term follow-up, when the mean age of the patients was 28 years (24 to 34), 20 hips had an unsatisfactory outcome (seven had OA and 13 had required THA). There was a strongly significant association between the modified Stulberg classification applied atfive-year follow-up and an unsatisfactory outcome at long-term follow-up (p < 0.001). Between the five- and 21-year follow-up, 67 hips (76%) stayed in their respective modified Stulberg group, indicating a strongly significant association between the Stulberg classifications at these follow-ups (p < 0.001). Conclusion. The modified Stulberg classification is a strong predictor of long-term radiological outcome in patients with Perthes’ disease. It can be applied at the healing stage, which is usually reached five years after the diagnosis is made and before skeletal maturity. Cite this article: Bone Joint J 2021;103-B(12):1815–1820

Aims. Perthes’ disease (PD) is a childhood hip disorder that can affect the quality of life in adulthood due to femoral head deformity and osteoarthritis. There is very little data on how PD patients function as adults, especially from the patients’ perspective. The purpose of this study was to collect treatment history, demographic details, the University of California, Los Angeles activity score (UCLA), the 36-Item Short Form survey (SF-36) score, and the Hip disability and Osteoarthritis Outcome score (HOOS) of adults who had PD using a web-based survey method and to compare their outcomes to the outcomes from an age- and sex-matched normative population. Methods. The English REDCap-based survey was made available on a PD study group website. The survey included childhood and adult PD history, UCLA, SF-36, and HOOS. Of the 1,182 participants who completed the survey, the 921 participants who did not have a total hip arthroplasty are the focus of this study. The mean age at survey was 38 years (SD 12) and the mean duration from age at PD onset to survey participation was 30.8 years (SD 12.6). Results. In comparison to a normative population, the PD participants had significantly lower HOOS scores across all five scales (p < 0.001) for all age groups. Similarly, SF-36 scores of the participants were significantly lower (p < 0.001) for all scales except for age groups > 55 years. Overall, females, obese participants, those who reported no treatment in childhood, and those with age of onset > 11 years had significantly worse SF-36 and HOOS scores. Pairwise correlations showed a strong positive correlation within HOOS scales and between HOOS scales and SF-36 scales, indicating construct validity. Conclusion. Adult PD participants had significantly worse pain, physical, mental, and social health than an age- and sex-matched normative cohort. The study reveals a significant burden of disease on the adult participants of the survey, especially females. Cite this article: Bone Joint J 2022;104-B(12):1304–1312

Perthes’ disease is an osteonecrosis of the juvenile hip, the aetiology of which is unknown. A number of comorbid associations have been suggested that may offer insights into aetiology, yet the strength and validity of these are unclear. This study explored such associations through a case control study using the United Kingdom General Practice Research database. Associations investigated were those previously suggested within the literature. A total of 619 cases of Perthes’ disease were included, as were 2544 controls. The risk of Perthes’ disease was significantly increased with the presence of congenital anomalies of the genitourinary and inguinal region, such as hypospadias (odds ratio (OR) 4.04 (95% confidence interval (CI) 1.41 to 11.58)), undescended testis (OR 1.83 (95% CI 1.12 to 3.00)) and inguinal herniae (OR 1.79 (95% CI 1.02 to 3.16)). Attention deficit hyperactivity disorder was not associated with Perthes’ disease (OR 1.01 (95% CI 0.48 to 2.12)), although a generalised behavioural disorder was (OR 1.55 (95% CI 1.10 to 2.17)). Asthma significantly increased the risk of Perthes’ disease (OR 1.44 (95% CI 1.17 to 1.76)), which remained after adjusting for oral/parenteral steroid use. Perthes’ disease has a significant association with congenital genitourinary and inguinal anomalies, suggesting that intra-uterine factors may be critical to causation. Other comorbid associations may offer insight to support or refute theories of pathogenesis

Introduction. Legg-Calve-Perthes (Perthes Disease) was first recognised by three physicians, Arthur Legg (1874–1939), Jacqui Calve (1875–1954) and George Perthes (1869 – 1927) in 1910. Perthes disease is a rare childhood condition that affects the hip. It occurs when the blood supply to the femoral head is disrupted. Without this blood supply, the bone cells die and avascular necrosis can occur. The Herring classification is used to diagnose the stages of Perthes Disease. It is an important prognostic factor. There are three classifications, Herring A, B and C. Herring A has no involvement of the lateral pillar with no density changes noted on x-ray. Herring B has at least 50% of the lateral pillar height maintained on x-ray. Herring C has less than 50% of the lateral pillar height on x-ray (Herring et al, 1992). Children with Perthes disease require specialist Limb Reconstruction team throughout their treatment journey, this includes Orthopaedic surgery and therapy (Physiotherapy and Occupational Therapy). The National Limb Reconstruction Therapy Team is based at the National Orthopaedic Hospital, Cappagh. The therapy team consists of 1 Clinical Specialist Physiotherapist, 1 Senior Physiotherapist and 1 Senior Occupational Therapist who provide input to this cohort. This study aims to analyse the importance of a comprehensive pre-operative assessment by the therapy team (Physiotherapist and Occupational Therapist) to maximise patient outcomes post operatively. Methodology. This is a quantitative research study conducted by the National Limb Reconstructive Therapy Service of the National Orthopaedic Hospital in Cappagh, Dublin. The inclusion criteria for this study consisted of:. Age – Patient must be part of the Paediatric Service, i.e., under the age of 16. Diagnosis – Patient must have a diagnosis of Perthes Disease with a Herring Classification documented. Application of a Hip Distractor Frame formed part of the patient's surgical management. Surgery was completed by Mr Connor Green. Surgery was completed between January 2021 and December 2022. Patient were required to have their external hip distractor frame removed by December 2022. Exclusion Criteria: Those not meeting the above inclusion criteria. Following the inclusion criteria, a number of cases were identified of which 10 cases were selected at random. A retrospective analysis of these samples was completed. The medical charts were reviewed as well as patient electronic healthcare records. Microsoft Excel was utilised to analyse the data and capture results. Results. From analysing the data, the following results were identified:. 80% of the sample cohort had a length of stay of 5 days following surgery. There were two outliers due to infection who had a length of stay of 14 days. 90% of the sample received a pre-operative Physiotherapy and Occupational Therapy assessment. This assessment included information gathering regarding the child's home and social environment; their functional baseline and anticipated post-operative needs. Standardised and non-standardised assessments were used. 88.89% of those who completed a pre-operative assessment required referral to community Occupational Therapy teams for equipment provision (wheelchair, transfer aids) to allow for timely discharge. On average, each patient in the sample required 17 physiotherapy outpatient sessions prior to handover to the community teams. 100% of our sample required post operation onward referral for MDT input in the community (Occupational Therapy and Physiotherapy). Conclusions. The importance of a multi-disciplinary approach towards family and children was highlighted in this study. A comprehensive pre-operative therapy assessment optimizes care for this cohort by preparing them in terms of equipment provisions, local team input and expectations for therapy. The data suggests future Limb Reconstruction team should include Physiotherapy and Occupational Therapy as part of the multi-disciplinary team, in the treatment of children with Perthe's Disease. We suggest an MDT pre-assessment is completed to optimize patient care, reduce length of stay and improve patient satisfaction in the acute hospital setting

The role of heritable thrombophilic risk factors in the pathogenesis of the Perthes’ disease is controversial. The clinical and radiological findings of Perthes’ disease may be indistinguishable from those of Gaucher’s disease, and the most common Jewish N370S Gaucher mutation is threefold greater in patients with Perthes’ disease. Familial osteonecrosis of the femoral head is associated with variant mutations of collagen type II (COL2A1 mutations). We therefore studied the potential role of genetic thrombophilia and the Gaucher and COL2A1 mutations in children with Perthes’ disease. Genomic DNA of 119 children with radiologically-confirmed Perthes’ disease diagnosed between 1986 and 2005 was analysed for the thrombophilic polymorphisms Factor V Leiden, 677T-MTHFR and FIIG20210A. The results were compared with those of a group of 276 children without Perthes’ disease. DNA was also analysed for the Gaucher mutations N370S, G insertion (84GG), L444P, Intron 2 (IVS2+1G> A) and R496H. Enzymic assays confirmed the Gaucher disease status. Collagen (COL2A1) mutations of the 12q13 gene were also analysed. The prevalence of thrombophilic markers was similar among the 119 patients with Perthes’ disease and the 276 control subjects. The prevalence of the Gaucher mutation was consistent with Israeli population carriership data and did not confirm an earlier-claimed association with Perthes’ disease. All 199 patients were negative for the studied COL2A1 mutations. We found no genetic association between Perthes’ disease and either Gaucher’s disease or COL2A1 mutations or increased genetic thrombophilia among our patients compared with the control group. A systematic review of case-control studies suggested that there was a positive association between Perthes’ disease and Factor V Leiden. The impact of this association upon the disease, although not consistent across the studies, remains unclear

Aims. Perthes’ disease (PD) often results in femoral head deformity and leg length discrepancy (LLD). Our objective was to analyze femoral morphology in PD patients at skeletal maturity to assess where the LLD originates, and evaluate the effect of contralateral epiphysiodesis for length equalization on proximal and subtrochanteric femoral lengths. Methods. All patients treated for PD in our institution between January 2013 and June 2020 were reviewed retrospectively. Patients with unilateral PD, LLD of ≥ 5 mm, and long-leg standing radiographs at skeletal maturity were included. Total leg length, femoral and tibial length, articulotrochanteric distance (ATD), and subtrochanteric femoral length were compared between PD side and the unaffected side. Furthermore, we compared leg length measurements between patients who did and who did not have a contralateral epiphysiodesis. Results. Overall, 79 patients were included, of whom 21 underwent contralateral epiphysiodesis for leg length correction. In the complete cohort, the mean LLD was 1.8 cm (95% confidence interval (CI) 1.5 to 2.0), mean ATD difference was 1.8 cm (95% CI -2.1 to -1.9), and mean subtrochanteric difference was -0.2 cm (95% CI -0.4 to 0.1). In the epiphysiodesis group, the mean LLD before epiphysiodesis was 2.7 cm (95% CI 1.3 to 3.4) and 1.3 cm (95% CI -0.5 to 3.8) at skeletal maturity. In the nonepiphysiodesis group the mean LLD was 2.0 cm (95% CI 0.5 to 5.1; p = 0.016). The subtrochanteric region on the PD side was significantly longer at skeletal maturity in the epiphysiodesis group compared to the nonepiphysiodesis group (-1.0 cm (95% CI -2.4 to 0.6) vs 0.1 cm (95% CI -1.0 to 2.1); p < 0.001). Conclusion. This study demonstrates that LLD after PD originates from the proximal segment only. In patients who had contralateral epiphysiodesis to balance leg length, this is achieved by creating a difference in subtrochanteric length. Arthroplasty surgeons need to be aware that shortening of the proximal femur segment in PD patients may be misleading, as the ipsilateral subtrochanteric length in these patients can be longer. Therefore, we strongly advise long-leg standing films for THA planning in PD patients in order to avoid inadvertently lengthening the limb. Cite this article: Bone Joint J 2021;103-B(11):1736–1741

Aims. To explore the of age of onset distribution for Perthes’ disease of the hip, with particular reference to gender, laterality and conformity to the lognormal distribution. Patients and Methods. A total of 1082 patients were identified from the Liverpool Perthes’ Disease Register between 1976 and 2010, of which 992 had the date of diagnosis recorded. In total, 682 patients came from the geographical area exclusively served by Alder Hey Hospital, of which 673 had a date of diagnosis. Age of onset curves were analysed, with respect to the predefined subgroups. Results. The age of onset demonstrated a positive skew with a median of 5.8 years (interquartile range 4.6 to 7.5). Disease onset was a mean five months earlier in girls (p = 0.01) and one year earlier in those who went on to develop bilateral disease (p < 0.001). There was no difference in the age of onset between geographical districts with differing incidence rates. The entire dataset (n = 992) conformed to a lognormal distribution graphically and with the chi-squared test of normality (p = 0.10), but not using the Shapiro-Wilk test (p = 0.01). The distribution for the predefined geographical subgroup (n = 673) conformed well to a lognormal distribution (chi-squared p = 0.16, Shapiro-Wilk p = 0.08). Given the observed lognormal distribution it was assumed that Perthes’ disease followed on incubation period consistent with a point-source disease exposure. The incubation period was further examined using Hirayama’s method, which suggested that the disease exposure may act in the prenatal period. Conclusion. The age of onset in Perthes’ disease conforms to a lognormal distribution, which allows comparisons with infectious disease epidemiology. Earlier onset in girls and those who develop bilateral disease may offer clues to understanding the aetiological determinants of the disease. The analysis suggests that an antenatal aetiological determinant may be responsible for disease. Take home message: Perthes’ disease age of onset conforms to a lognormal model, which is most typical of infectious diseases. The shape of the distribution suggests that an aetiological trigger in the pre-natal period may be an important determinant of disease. Cite this article: Bone Joint J 2016;98-B:710–14

Aims. The aims of this study were to describe the course of non-operatively managed, bilateral Perthes’ disease, and to determine specific prognostic factors for the radiographic and clinical outcome. . Patients and Methods. We identified 40 children with a mean age of 5.9 years (1.8 to 13.5), who were managed non-operatively for bilateral Perthes’ disease from our prospective, multicentre study of this condition, which included all children in Norway who were diagnosed with Perthes’ disease in the five-year period between 1996 and 2000. All children were followed up for five years. . The hips were classified according to the Catterall classification. A modified three-group Stulberg classification was used as an outcome measure, with a spherical femoral head being defined as a good outcome, an oval head as fair, and a flat femoral head as a poor outcome. . Results. Concurrent, simultaneous bilateral Perthes’ disease was seen in 23 children and 17 had the sequential onset of bilateral disease. The mean delay in onset for the second hip in the latter group was 1.9 years (0.3 to 5.5). . The five-year radiographic outcome was good in 30 (39%), fair in 25 (33%) and poor in 21 (28%) of the hips. The strongest predictors of poor outcome were > 50% necrosis of the femoral head, with odds ratio (OR) 19.6, and age at diagnosis > 6 years (OR 3.3). Other risk factors for poor outcome were the timing of the onset of disease, where children with the sequential onset of bilateral disease had a higher risk than those with the concurrent onset of bilateral disease (p = 0.021, chi-squared test). . Following a diagnosis of Perthes’ disease in one hip, there was a 5% chance of developing it in the contralateral hip. . Conclusion. These results imply that we need to distinguish between children with concurrent onset and those with sequential onset of bilateral Perthes’ disease, as the outcomes may be different. This has not been previously described. Children with concurrent onset of bilateral disease had a similar outcome to our previous series of those with unilateral disease, whereas children with sequential onset of bilateral disease had a worse prognosis. The increased risk of developing Perthes’ disease in the contralateral hip in those with unilateral disease is important information for the child and parents. . Cite this article: Bone Joint J 2016;98-B:569–75

This paper reports a high incidence of minor congenital anomalies in boys and girls with Perthes' disease compared with that in a control population. There is a similarity of the incidence of minor anomalies in the children with Perthes' disease to that in babies with a single major congenital defect. Multiple major defects were more numerous and more severe than in the control children. It is speculated that there may be a congenital abnormality affecting skeletal development which in some way makes the hip susceptible to Perthes' disease at a later date

It has been reported that there is an association between Perthes’ disease and poverty. We examined the demographic data of a group of 240 children (263 hips) who presented with Perthes’ disease in Greater Glasgow, where the mean deprivation scores are substantially greater than in the rest of Scotland, to see if this association applied and whether other clues to the aetiology of Perthes’ disease could be found. There were 197 boys and 43 girls; 39 (16.25%) had a family history of Perthes’ disease. Bone age in this series was heavily skewed towards the lower percentiles. The mean number of siblings was 1.9, with 31 (12.9%) being an only child. Maternal age at the birth of the first child showed no preponderance of older mothers. Maternal smoking during and after pregnancy was noted in 132 (55%), which compared with the 52% reported in the population of Greater Glasgow in general. Of the children in our series, 60 (25%) were in social class IV and V. However, this applies to more than half of the population of Greater Glasgow. There was no significant evidence of a preponderance of Perthes’ disease in the most deprived groups. The aetiology of Perthes’ disease is likely to be multifactorial and may include a genetic or deprivation influence resulting in delayed bone age

We have investigated the annual incidence of Perthes’ disease in Dumfries and Galloway (Southwest Scotland), in relation to the population density and socio-economic status. The incidence of Perthes’ disease in rural Scotland is comparable with that in urban areas (15.4 per 100 000). There was a direct association between the incidence of Perthes’ disease and deprivation scores, with the highest incidence in the most deprived areas. A higher incidence of Perthes’ disease was noted in areas with a lower population density compared with those with a higher density. We found no correlation between population density and deprivation scores for individual electoral wards within the region

Our aim was to investigate the relationship between urinary excretion of deoxypyridinoline (DPD) as a marker of bone resorption, and Perthes’ disease. There were 39 children with Perthes’ disease in the florid stage who collected first-morning urine samples at regular intervals of at least three months. The level of urinary DPD was analysed by chemiluminescence immunoassay and was correlated with the radiological stage of the disease as classified by Waldenström, and the severity of epiphyseal involvement according to the classification systems of Catterall and Herring. The urinary DPD levels of a group of 44 healthy children were used as a control. The median urinary DPD/creatinine (CREA) ratio was significantly reduced (p < 0.0001) in the condensation stage and increased to slightly elevated values at the final stage (p = 0.05) when compared with that of the control group. Herring-C patients showed significantly lower median DPD/CREA ratios than Herring-B patients (p = 0.03). The significantly decreased median DPD/CREA ratio in early Perthes’ disease indicated a reduced bone turnover and supports the theory of a systemic aetiology. Urinary levels of DPD may therefore be used to monitor the course of Perthes’ disease

A nationwide study of Perthes’ disease in Norway was undertaken over a five-year period from January 1996. There were 425 patients registered, which represents a mean annual incidence of 9.2 per 100 000 in subjects under 15 years of age, and an occurrence rate of 1:714 for the country as a whole. There were marked regional variations. The lowest incidence was found in the northern region (5.4 per 100 000 per year) and the highest in the central and western regions (10.8 and 11.3 per 100 000 per year, respectively). There was a trend towards a higher incidence in urban (9.5 per 100 000 per year) compared with rural areas (8.9 per 100 000 per year). The mean age at onset was 5.8 years (1.3 to 15.2) and the male:female ratio was 3.3:1. We compared 402 patients with a matched control group of non-affected children (n = 1 025 952) from the Norwegian Medical Birth Registry and analysed maternal data (age at delivery, parity, duration of pregnancy), birth length and weight, birth presentation, head circumference, ponderal index and the presence of congenital anomalies. Children with Perthes’ disease were significantly shorter at birth and had an increased frequency of congenital anomalies. Applying Sartwell’s log-normal model of incubation periods to the distribution of age at onset of Perthes’ disease showed a good fit to the log-normal curve. Our findings point toward a single cause, either genetic or environmental, acting prenatally in the aetiology of Perthes’ disease

Aims. Modular or custom-made femoral components have been preferred for total hip arthroplasty (THA) in patients with a history of Perthes’ disease because of the distortion in the anatomy of the proximal femur. However, it has not been established whether a monobloc cementless stem will fit the distorted proximal femur or whether the results of the procedure are satisfactory in this group of patients. Patients and Methods. We reviewed 68 consecutive patients who had undergone THA for childhood Perthes’ disease between June 2003 and December 2008. There were 35 men and 33 women with a mean age of 48 years (16 to 73) at the time of index arthroplasty. Their mean body mass index was 24.4 (18.3 to 32.9). Of the 68 hips, 32 were classified as Stulberg class III and 36 as class IV. The mean pre-operative shortening of the affected leg was 17.2 mm (5 to 34). The minimum follow-up was five years (mean 8.5 years; 5.2 to 10). Results. An intra-operative calcar fracture occurred in eight hips (11.8%) and was successfully treated by cerclage wiring. The mean stem version was 14.6° (-2.3 to 30; standard deviation (. sd. ) 7.3). The mean acetabular component abduction was 40.2° (23.7 to 56.0; . sd. 6.5) and the mean anteversion 28.3° (6.4 to 43.0; . sd. 7.6), respectively. The mean follow-up was 8.5 years (5.2 to 10). No dislocations occurred and no hips were revised during the course of the study. At final follow-up, the mean Harris Hip Score was 91 points (59 to 100) and the mean University of California, Los Angeles activity score was 3.2 (2 to 8). Conclusion. Monobloc cementless stems reliably restore the anatomy in Perthes’ disease at THA without the need for custom-made or modular implants. Cite this article: Bone Joint J 2017;99-B:440–444

Introduction. 2010 marked a century since Perthes' disease was first described, but the aetiology and mechanism remain unknown. Worldwide, the incidence of Perthes' disease varies widely, yet this may be through differences in study design, population denominators or case ascertainment. It is suggested that differential exposure to adverse socioeconomic circumstances may be a key precipitant, although this remains the subject of debate. This work draws on several epidemiological studies that have sought to develop the understanding of Perthes' disease by examining a case register from Merseyside, discharge data from Scotland and the world's largest community disease register. A systematic review was performed to ensure a robustness and homogeneity between published studies in order to allow meaningful comparisons. Methods. Studies were based on data from the Merseyside Perthes' Disease Register (1976–2008), the UK General Practice Research Database (GPRD, 1990–2008) and hospital discharge data for Scotland (2000–2009). Temporal trends and geographic patterns were analysed and the relationship to deprivation investigated. A systematic review of the published literature was used to explore international variations in incidence up to December 2010 focusing upon the influence of race and latitude. Analyses were conducted using Poisson regression. Results. Systematic Review: 21 studies were included which described 27 populations in 16 countries, observing 124 million person years. The annual incidence ranged from 0.2 – 19.1 per 100,000 0–14 year-olds. Race was a key determinant with East Asians least affected and Whites most affected (East Asian IRR 1.0 (Ref), South Asian IRR 2.9 (2.4, 3.5), White IRR 8.8 (8.2, 9.6)). Latitude was a strong predictor of disease, even after adjusting for race. Each 10 degree increase in latitude resulted in the incidence rate increasing by a factor of 1.44 (1.30, 1.58). GPRD Study. There was a dramatic decline in Perthes' disease incidence within the UK, with annual incidence rates falling from 12.2 to 5.7 cases/100,000 0–14 year-olds over the 19 year study period (p<0.001). There was marked geographic variation in incidence with incidence rates in Scotland more than twice those in London (10–39 (95%CI 8.05 – 13.2) vs 4.6 (95% CI 3.4 – 6.1) per 100.000 0–14 year-olds). A more rapid decline in incidence was apparent in the Northern regions compared to Southern regions. The most deprived quintile had the highest disease incidence (rate ratio 1.49 (95% CI 1.10 – 2.04)) and, with the exception of London, regional incidence showed a strong linear relationship to regional deprivation score (p<0.01). Merseyside. There was a dramatic decline in Perthes' disease incidence within Liverpool with rates falling from 14.2 to 7.7 cases/100,000 0–14 year-olds over the 34-year study period (p<0.001). Incidence rates similarly halved within the nearby region of Knowsley (p=0.01) but remained largely static in the more affluent regions of Sefton where the incidence has remained around 7.2 cases/100,000 0–14 year-olds (p=0.73). The association with socioeconomic deprivation is striking with over three times the incidence in the most deprived quintile of multiple deprivation compared to the most affluent quintile of IMD (11.5 vs 3.8 cases/100.000 0–14 year-olds (p<0.001). The incidence, by ward region, was strongly correlated to the ward index of deprivation (p<0.001) (IRR 1.014 (1.007 – 1.021)). Scotland. Hospital discharge rates due to Perthes' disease fell annually by 5.6% (95% CI 2.4% – 8.8% p<0.001) between 2000–2010. Given that there has been no significant change in treatment practice during this period and the results of the above studies, this is likely to represent a real change in disease incidence. There was a strong association between socioeconomic deprivation and disease with rates amongst the most deprived quintile more than twice those of the most affluent (RR 2.1 (1.5 – 2.9)). Similar incidence gradients for deprivation were seen in both urban and rural environments. Conclusions. These studies provide strong evidence to suggest a declining incidence of Perthes' disease within the UK and a strong relationship to socioeconomic deprivation. Although Perthes' disease incidence is falling it remains an important cause of child morbidity and exemplifies socioeconomic inequalities in health. The striking UK North–South divide is similar to that seen in adult diseases such as cardiovascular disease and osteoporosis. Latitude has an independent association with disease which may be through the action of sunlight and Vitamin D. A deprivation-related exposure (probably acting prenatally) appears critical but the aetiological determinants remain elusive

Purpose of the study is to investigate the outcome of the patients with Perthes disease who have had a surgical dislocation of their hip for the treatment of resultant symptoms from the disease process. Retrospective review of consecutive patients treated with surgical dislocation of the hip for Perthes disease. Review of clinical case notes and radiological imaging. Patient outcome was assessed at follow-up. Between 2010 and 2015, 31 cases of surgical hip dislocation were performed for Perthes disease at our institution by 2 senior surgeons. Age range at time of surgery was 12–33. Male:female ratio was 13:18; right:left ratio was 15:17. Age at the time of Perthes diagnosis was between 3 and 13 years, with 3 diagnosed retrospectively. Mean follow-up was 18months. All patients had an EUA and arthrogram while 61.3%(19/31) had previous surgery for Perthes. 71%(22/31) required a labral repair, 6.5%(2/31) had a peri-acetabular osteotomy at the time of surgery and 3.2%(1/31) required a proximal femoral valgus osteotomy. 22.5%(7/31) required microfracture (femoral head or acetabulum): all of whom had evidence of contained area of degenerative changes on preoperative MRI. 64.5%(20/31) had the trochanteric screws removed. Complications included 1 greater trochanter non-union, 1 pain secondary to suture anchor impinging on psoas tendon, 1 AVN leading to early THR 12 months post-op. Another 2 had further deterioration of degenerative changes and pain leading to THR 18 and 24 months post-op. All 3(9.7%) had microfracture at the time of the dislocation for established degenerative change and also required custom made prostheses. Surgical hip dislocation is an option in treating Perthes patient with resultant symptoms such as impingement. Improved outcome is seen in patients who are younger with a congruent hip joint in contrast to those with established degenerative change evident on MRI / intraoperatively and have an arrow shaped femoral head

The purpose of this study was to determine the annual incidence of Perthes’ disease in Korea and compare this with other populations. A survey identified all newly diagnosed children with Perthes’ disease aged 14 years or younger in South Honam, Korea, between January 1999 and December 2001. A total of 84 children were included: 29 in 1999, 28 in 2000 and 27 in 2001. The mean annual incidence was 3.8 per 100 000. This is similar to that reported in other Asian countries, but higher than in black populations and lower than in Caucasians

Children presenting with Perthes’ disease before their sixth birthday are considered to have a good prognosis. We describe 166 hips in children in this age group. The mean age at onset of the disease was 44 months (22 to 72). Mild forms (Catterall I and II) were treated conservatively and severe forms (Catterall III and IV) either conservatively or operatively. The aim of the former treatment was to restrict weight-bearing. Operative treatment consisted of innominate osteotomy and was indicated by a Conway type-B appearance on the bone scan. All the patients were followed to skeletal maturity with a mean follow-up of 11 years (8 to 15). The end results were evaluated radiologically using the classifications of Stulberg and Mose. A total of 50 hips were Catterall grade-I or grade-II, 65 Catterall grade-III and 51 Catterall grade-IV. All hips with mild disease had a good result at skeletal maturity. Of the hips with severe disease 78 (67.3%) had good (Stulberg I and II), 26 (22.4%) fair (Stulberg III) and 12 (10.3%) poor results (Stulberg IV and V). Of the Catterall grade-III hips 38 were treated conservatively of which 31 (81.6%) had a good result, six (15.8%) a fair and one (2.6%) a poor result. Operative treatment was carried out on 27 Catterall grade-III hips, of which 21 (77.8%) had a good, four (14.8%) a fair and two (7.4%) a poor result. By comparison conservative treatment of 19 Catterall grade-IV hips led to ten (52.7%) good, seven (36.8%) fair and two (10.5%) poor results. Operative treatment was carried out on 32 Catterall grade-IV hips, of which 16 (50.0%) had a good, nine (28.1%) a fair and seven (21.9%) a poor result. We confirm that the prognosis in Perthes’ disease is generally good when the age at onset is less than six years. In severe disease there is no significant difference in outcome after conservative or operative treatment (p > 0.05). Catterall grade-III hips had a better outcome according to the Stulberg and Mose criteria than Catterall grade-IV hips, regardless of the method of treatment

The deformity index is a new radiological measurement of the degree of deformity of the femoral head in unilateral Perthes’ disease. Its values represent a continuous outcome measure of deformity incorporating changes in femoral epiphyseal height and width compared with the unaffected side. The sphericity of the femoral head in 30 radiographs (ten normal and 20 from patients with Perthes’ disease) were rated blindly as normal, mild, moderate or severe by three observers. Further blinded measurements of the deformity index were made on two further occasions with intervals of one month. There was good agreement between the deformity index score and the subjective grading of deformity. Intra- and interobserver agreement for the deformity index was high. The intraobserver intraclass correlation coefficient for each observer was 0.98, 0.99 and 0.97, respectively, while the interobserver intraclass correlation coefficient was 0.98 for the first and 0.97 for the second set of calculations. We also reviewed retrospectively 96 radiographs of children with Perthes’ disease, who were part of a multicentre trial which followed them to skeletal maturity. We found that the deformity index at two years correlated well with the Stulberg grading at skeletal maturity. A deformity index value above 0.3 was associated with the development of an aspherical femoral head. Using a deformity index value of 0.3 to divide groups for risk gives a sensitivity of 80% and specificity of 81% for predicting a Stulberg grade of III or IV. We conclude that the deformity index at two years is a valid and reliable radiological outcome measure in unilateral Perthes’ disease

This nationwide prospective study was designed to determine prognostic factors and evaluate the outcome of different treatments of Perthes’ disease. A total of 28 hospitals in Norway were instructed to report all new cases of Perthes’ disease over a period of five years and 425 patients were reported and followed for five years. Of these, 368 with unilateral disease were included in the present study. The hips were classified radiologically according to a modified two-group Catterall classification and the lateral pillar classification. A total of 358 patients (97%) attended the five-year follow-up, when a modified three-group Stulberg classification was used as a radiological outcome measure. For patients over six years of age at diagnosis and with more than 50% necrosis of the femoral head (152 patients), the surgeons at the different hospitals had chosen one of three methods of treatment: physiotherapy (55 patients), the Scottish Rite abduction orthosis (26), and proximal femoral varus osteotomy (71). Of these hips, 146 (96%) were available for the five-year follow-up. The strongest predictor of outcome was femoral head involvement of more or less than 50% (odds ratio (OR) = 7.76, 95% confidence interval (CI) 2.82 to 21.37), followed by age at diagnosis (OR = 0.98, 95% CI 0.92 to 0.99) and the lateral pillar classification (OR = 0.62, 95% CI 0.40 to 0.98). In children over six years at diagnosis with more than 50% of femoral head necrosis, proximal femoral varus osteotomy gave a significantly better outcome than orthosis (p = 0.001) or physiotherapy (p = 0.001). There was no significant difference between the physiotherapy and orthosis groups (p = 0.36), and we found no difference in outcome after any of the treatments in children under six years (p = 0.73). We recommend proximal femoral varus osteotomy in children aged six years and over at the time of diagnosis with hips having more than 50% femoral head necrosis. The abduction orthosis should be abandoned in Perthes’ disease

Northern Ireland has previously demonstrated high incidence of Perthes' disease (11.6 per 100,000). The aim of this study is to confirm a declining incidence in this diagnosis in Northern Ireland. Methods. A reduction in new Perthes' patients had been noted by the senior author. A retrospective study was designed to identify patients with a new diagnosis of this disease over a 7 year period (2004–10). Clinical notes were interrogated using word searches. Further cross referencing with x-ray system reports were utilised to capture all new patients presenting with subsequently proven Perthes'. Patients not resident in Northern Ireland at the time of diagnosis were excluded. Patients with epiphyseal dysplasia or avascular necrosis secondary to treatment of developmental dysplasia of the hip were also excluded. A previous study from this unit had demonstrated 313 new cases over the 7 year period 1992–1998, with average incidence of approximately 45/year for the population. Results. All years in our study (2004–10) have had less than 30 for the entire population (<8.3 per 100,000). Significant variation between years with some years much less detected, so further searches are been undertaken to ensure completeness if data capture. Conclusions. Perthes' disease incidence appears to have reduced significantly. Factors such as a lower threshold for investigation, better radiological diagnostics and better understanding of Perthes' should artificially increase the incidence. However, these study findings suggest a decrease. Passive smoking has long been debated as a possible cause in Perthes' disease. The prevalence of smoking is falling in N. Ireland. The 2007 introduction of a workplace smoking ban coincided with a statistically significant fall in smoking behaviour from 25% in 2006/07 to 23% in 2007/08. The cause of Perthes' is undoubtedly multifactorial, but these findings do coincide with decreasing smoking habits in this captive population

We studied 16 patients suffering from osteoarthritis of the hip who had had Perthes’ disease during childhood. They were compared clinically and radiologically with a control group who had not had Perthes’ disease, in order to assess whether a generalised, pre-existing constitutional disorder was present. Nine patients with a previous history of Perthes’ disease had some other skeletal abnormality, but only three presented with clinical symptoms. Only one patient in the control group was found to have an abnormality but was symptom-free. Our findings provide further evidence that patients with Perthes’ disease may have a generalised abnormality related to chondrogenesis which can produce other skeletal anomalies that persist into adult life

Aims. It is well established that there is a strong association between Perthes’ disease and worsening socioeconomic deprivation. It has been suggested that the primary determinant driving this association is exposure to tobacco smoke. This study aimed to examine this hypothesis. Patients and Methods. A hospital case-control study (n = 149/146) examined the association between tobacco smoke exposure and Perthes’ disease, adjusting for area-level socioeconomic deprivation. Tobacco smoke exposure was assessed by parental questionnaire of smoking habits during pregnancy, and by quantitative assay of current exposure using the urinary cotinine-creatinine ratio, which is a widely used and validated measure of tobacco smoke exposure. Results. The odds of Perthes’ disease significantly increased with reported in utero exposure after adjustment for socioeconomic deprivation (maternal smoking odds ratio (OR) 2.06, 95% confidence interval (CI) 1.17 to 3.63; paternal smoking OR 2.09, 95% CI 1.26 to 3.46). The cotinine-creatinine ratio was significantly greater in cases, OR 1.63 (95% CI 1.09 to 2.43), suggesting a greater ‘dose’ of current tobacco exposure. Conclusion. An association exists between tobacco smoke exposure and Perthes’ disease but we remain unable to disentangle the association with socioeconomic deprivation. Cite this article: Bone Joint J 2017;99-B:1102–8

This study sought to determine the genetic contribution of Perthes' disease, using the world's largest twin-registry. We extracted all twin pairs from the Danish Twin Registry (DTR) in which at least one individual had Perthes' Disease. The DTR captures every twin pair born alive in Denmark. Those with Perthes' disease were identified using health record linkage to the Danish Morbidity Record. Probandwise concordance was calculated to describe the likelihood that any given individual had LCPD if their co-twin was also diagnosed. There were 81 twin pairs; 10 monozygotic (MZ), 51 dizygotic (DZ), and 20 unclassified (UZ). There was no association between birth weight and being the affected co-twin. Four pairs (two dizygotic and two unclassified) were concordant for LCPD, which is greater than would be expected assuming no familial aggregation. There were no concordant MZ twin pairs. The overall probandwise concordance was 0.09 (95% CI 0.01–0.18): 0.00 for the MZ, 0.08 (95% CI 0.00–0.18) for the DZ, and 0.18 (95% 0.00–0.40) for the UZ twin pairs. This study found evidence of familial clustering in LCPD but did not demonstrate a genetic component. The absolute risk that a co-twin of an affected individual will develop LCPD is low, even in the case of MZ twin pairs

Perthes disease is a childhood disorder often resulting in femoral head deformity. Categorical/dichotomous outcomes of deformity are typical clinically, however quantitative, continuous measures, such as Sphericity Deviation Score (SDS), are critical for studying interventions. SDS uses radiographs in two planes to quantify femoral head deformity. Limitations of SDS may include non-orthogonal planes and lost details due to projections. We applied this method in 3D, with specific objectives to: 1. Develop SDS-like sphericity measures from 3D data 2. Obtain 2D and 3D sphericity for normal and Perthes hips 3. Compare slice-based (3D) and projection-based (2D) sphericity CT images of 16 normal (8 subjects) and 5 Perthes hips (4 subjects) were segmented to create 3D hip models. Ethics board approval was obtained for this study. SDS consists of roundness error (RE) in two planes and ellipsoid deformation (ED) between planes. We implemented a modified SDS which was applied to (a) orthogonal projections simulating radiographs (sagittal/coronal; 2D-mSDS), and (b) largest radii slices (sagittal/coronal; 3D-mSDS). Mean 2D-mSDS was higher for Perthes (27.2 (SD 11.4)) than normal (11.9 (SD 4.1)). Mean 3D-mSDS showed similar trends, but was higher than 2D (Perthes 33.6 (SD 5.3), normals 17.0 (SD 3.1)). Unlike 2D-mSDS, 3D-mSDS showed no overlap between groups. For Perthes hips, 2D-mSDS was consistent with SDS. For normal hips, 2D-mSDS was higher than expected (similar to Stulberg II). Projection-based (2D) measures may produce lower mSDS due to spatial averaging. Slice-based (3D) measures may better distinguish between normal and Perthes shapes, which may better differentiate effectiveness of treatments

Objective. To compare the effectiveness of arthrodiastasis with shelf acetabuloplasty for Perthes' disease in older children, by assessing the radiological outcome in matched pairs of children at skeletal maturity. Design. Retrospective observational study case series. Patients and Methods. Children were selected who had Perthes' disease, which was in the initial or fragmentation stage at presentation, with a chronological age > 7 years at diagnosis and Grade B or B/C borderline (using the modified Herring's lateral pillar classification). Exclusion criteria were other surgery for Perthes', and if they were skeletally immature at time of latest follow up. The matching criteria were age at diagnosis, sex, ethnicity, modified lateral pillar classification. The children who had a shelf were drawn from one institution and arthrodiastasis from the other. In both centres, the prevalence of Perthes' is similar. 11 matched pairs were identified (22 children). Main outcome measures. Stulberg class at skeletal maturity and complications Results - There was no statistical difference between the Stulberg class at maturity in the two groups. 6 pairs had the same class. One shelf patient developed a temporary peroneal nerve palsy. Nine of the eleven arthrodiastasis patients developed pin track infections and one had a pin breakage. Conclusion. The study is limited by small numbers, but the radiographic results appear similar. The complications were different. Both appear valid options for B or B/C border hips before onset of head deformity, but ultimately the choice of treatment depends on patient and surgeon preference

Objective. There is mounting evidence to suggest a vascular insult is responsible for Perthes' disease, and it is suggested that this may have long-term implications for the vascular health of affected individuals. This study sought to use ultrasound measures to investigate vascular structure and function in children affected by Perthes' disease. Material and Methods. This case control study encompassed 149 cases and 146 controls, frequency matched for age and sex. Endothelial function was measured using the technique of flow-mediated dilatation of the brachial artery, and alterations in arterial flow were recorded in response to an ischaemic stimulus. Results. There was a significant structural alteration in the vasculature amongst individuals with Perthes' disease (resting brachial artery diameter (cases 2.97mm vs. controls 3.11mm; p=0.01)), which remained even after adjusting for height. Additionally, there was a notable reduction in blood velocity (cases 33.84cm/sec vs controls 37.83cm/sec; p=0.01) and blood flow (cases 149.82ml/min vs. controls 184.67 ml/min; p=0.001), which was independent of baseline arterial size. There was no evidence to suggest that flow mediated dilatation of the brachial artery was impaired amongst affected individuals (p=0.71). Conclusion. Children with Perthes' disease exhibit small artery calibre and reduced function, which is independent of body composition. This data implies that that Perthes' disease may reflect a wider vascular phenomenon that could have long-term implications for the vascular health of affected individuals

Femoral head deformity can be a devastating outcome in a small percentage of patients with Perthes' disease. Deformities usually start during the fragmentation stage. In this study, we aimed to determine the effects of Vitamin D deficiency on the natural history of Perthes' disease. Patients with Perthes' disease and Vitamin D deficiency presenting to our unit in the last 3 years were identified. All X-rays were reviewed retrospectively to determine the duration of the fragmentation and ossification stages. Treatment methods were obtained from the notes. Late presenters (i.e. after fragmentation stage) were excluded. In our unit, Vitamin D deficiency is diagnosed if levels <72 nmol/L. Fifteen patients (17 hips) with Perthes' disease were found to be Vitamin D deficient. Levels ranged from (18–71 nmol/L). The mean length of the fragmentation stage was 15.7 months which is significantly higher than quoted literature figures (8 months). Ossification stage duration was 18.8 months which was comparable to quoted figures. However, patients with severe Vitamin D deficiency (< 52 nmol/L) were found to have longer ossification stage (20.6 months) compared with patients with mild deficiency (52–72 nmol/L) (16.4 months). Seven out of 16 patients (44%) required surgical containment which is significantly higher than the usually low rates of surgical intervention. The critical fragmentation stage in Vitamin D deficiency is significantly longer putting the femoral head at higher risk of deformity and extrusion. This leads to higher rates of surgical containment. Also the severity of Vitamin D deficiency might be an important determinant of the period of time required for ossification and healing. Vitamin D level is an important prognostic factor and must be measured in all patients with Perthes' disease. Prescribing Vitamin D supplements is advisable in this group of patients. However, the effects of these supplements on the course of the disease requires further research. Level of evidence: III

It has been shown that in the puppy, two infarcts separated by an interval of four weeks produce a disorder of long duration which results in flattening and broadening of the femoral head and which reproduces the radiological changes seen in Perthes' disease in man. The histological appearances produced by two infarcts are characteristic. In this study the histological appearance of fifty-seven femoral head biopsy specimens in Perthes' disease in man have been studied. In 51 per cent of hips histopathological changes characteristic of double infarction were present, and there were grounds for postulating that double infarction might eventually occur in all cases. The findings support the concept that the deformation of the femoral head and the chronicity of Perthes' disease in man may be due at least as much or even more to repeated episodes of infarction and the ensuing abnormalities of growth as to mechanical factors related to weight-bearing

Recent reports have suggested an association between Perthes’ disease and an underlying thrombophilic or hypofibrinolytic tendency. In Northern Ireland there is a high incidence of Perthes’ disease (11.7 per 100 000 or 1 in 607 children) in a stable paediatric population. We reviewed 139 children with Perthes’ disease and compared them with a control group of 220 aged- and gender-matched healthy primary schoolchildren with similar racial and ethnic backgrounds. There were no significant deficiencies of antithrombotic factors protein C, protein S, antithrombin III or resistance to activated protein C. A total of 53 (38.1%) of the children with Perthes’ disease had a prolonged activated partial thromboplastin time (> 38) compared with 13 (5.9%) of the control group (p < 0.001). Our findings have shown that using standard assays, thrombophilia secondary to antithrombotic factor deficiency or resistance to activated protein does not appear to be an aetiological factor for Perthes’ disease. The cause of the prolonged activated partial thromboplastin time, usually associated with a clotting factor deficiency, is under further investigation

Aims: To assess the value of hip arthrography in planning definitive treatment for children with DDH and Perthes’ disease. Background: It is sometimes unclear whether children with DDH and Perthes’ disease need an operation. Surgeons are guided by the clinical symptoms and signs together with the radiographic appearances of the affected hip. In our Unit children on whom an operation is considered undergo an examination under anaesthetic (EUA) and a hip arthrogram. This prospective study was developed to assess whether treatment was modified by the arthrogram. Methods: All patients who underwent an EUA and hip arthrogram for DDH or Perthes’ disease over a 10 month period were entered into this prospective study. Prior to arthrography a Consultant Children’s Orthopaedic Surgeon formulated a treatment plan. A standard arthrogram was performed which included anteroposterior, frog lateral, Von Rosen and oblique views. Traction axial loading views were taken to assess stability. Following EUA and arthrogram the Consultant Surgeon formulated a definitive treatment plan. Three Children’s Consultants were then invited subsequently to review the preoperative and arthrographic appearances blindly to monitor reproducibility. Twenty-one patients with DDH and 19 with Perthes’ disease were entered into the study. Results: In the DDH group of patients the treatment plan was modified in 12 of the 21 patients as a consequence of the arthrogram. Six of the 19 patients (31.6 %) of the Perthes’ affected patients had their treatment modified. When it was felt likely prior to EUA a conservative treatment was indicated. The correlation of intra-observer Consultant agreement was high but inter-observer Consultant agreement was moderate only. In both groups of patients the range of hip motion was significantly greater under anaesthesia. Conclusion: Static and dynamic arthrography helps decision making in patients with DDH and Perthes’ disease

Over the last several years, triple pelvic osteotomy has become our preferred method for surgical containment in Perthes disease. Since 1995, seventeen patients with Perthes disease have been treated with triple pelvic oste-otomy at our institution. Fourteen of seventeen patients (82%) had a good or excellent clinical result at latest follow-up. According to Sundt’s criteria, radiographic outcome was rated as good in fourteen patients (82%), fair in one patient and poor in two patients. Experience with the technical aspects of the procedure is necessary to avoid pseudarthrosis and iatrogenic external rotation of the acetabular fragment. To evaluate the efficacy of triple pelvic osteotomy as a method of surgical containment in Perthes disease. Recent trends point to surgery as the method of choice for containment in older children with Perthes disease. Over the last several years, triple pelvic osteotomy has become our preferred method for surgical containment in Perthes disease. Since 1995, seventeen patients (seventeen hips) with Perthes disease classified as either lateral pillar B or C have been treated with triple pelvic osteotomy at our institution. The average age at surgery was 8.5 years with an average follow-up of 4.3 years. Outcome was assessed using clinical as well as multiple radiographic criteria. Fourteen of seventeen patients (82%) had a good or excellent clinical result at latest follow-up. No patients had a residual limp or limb length inequality. Two patients had a minor postoperative complication (transient peroneal nerve palsy, meralgia paresthetica). According to Sundt’s criteria, radiographic outcome was rated as good in fourteen patients (82%), fair in one patient and poor in two patients. Triple pelvic osteotomy minimizes potential complications associated with other surgical methods such as Trendelenberg gait and shortening with proximal femoral osteotomy or hinge abduction following a Salter innominate osteotomy. Experience with the technical aspects of the procedure is necessary to avoid pseudarthrosis and iatrogenic external rotation of the acetabular fragment. Triple pelvic osteotomy is now our procedure of choice for containment in the older child with Perthes disease

Radiographs of 155 Indian children were examined to identify the acetabular changes which occur in Perthes' disease. These changes included osteoporosis of the acetabular roof, irregularity of contour, premature fusion of the triradiate cartilage, hypertrophy of articular cartilage and changes in dimensions. These changes tended to be more marked in older children and when more than half of the femoral epiphysis was involved. Comparison with 25 cases of Perthes' disease from Liverpool showed the same picture. Several of the acetabular changes noted during the active stages were also seen in a series of 24 adult hips after Perthes' disease. Radio-isotope scans of the hips of 27 children with Perthes' disease showed a consistently increased uptake in the acetabulum on the affected side, indicative of a local increase in vascularity and metabolic activity. It was possible to postulate a working model for the pathogenesis of all the acetabular changes. A number of statistical correlations suggest that most of the changes have a bearing on the final outcome

1. Perthes' disease is an ischaemic lesion of the ossific nucleus of the head of the femur which may vary both in extent and degree. It is probably never quite complete. 2. When part of the ossific nucleus only is affected, as is usually the case, it is almost invariably the antero-lateral part. 3. The process of absorption of the damaged bone is complete radiologically before there is radiological evidence of reossification. 4. Reossification always occurs in Perthes' disease. 5. The aim of treatment must be to see that the mould in which the head is shaped is the right shape when ossification occurs. 6. The deformity of the head of the femur does not occur from pressure alone, but from pressure combined with subluxation. Full unrestricted weight-bearing can be allowed with safety on a femoral head in which there are ischaemic changes provided the femoral head is well contained. 7. The time of treatment can be very greatly reduced by using operation to correct the subluxation instead of relying on external splintage. This can be achieved by subtrochanteric osteotomy with rotation, or rotation combined with varus angulation. 8. Perthes' disease and avascular necrosis of the head of the femur are different conditions with different characteristics. 9. Suggestions are made as to the nature of the disease in relation to absorption, continued growth and reossification

We used ultrasonography to examine 36 children suffering from transient synovitis and 12 children with early Perthes' disease. Widening of the joint space was revealed by ultrasonography in all affected hips with either disease. In the patients with transient synovitis, capsular distension was attributed to synovial effusion, while in the patients with Perthes' disease it was produced by thickening of the synovial membrane. Neither capsular distension nor thickening of the joint cartilage was seen in the contralateral normal hip in the patients with transient synovitis, but they were common in early Perthes' disease. Ultrasonography may provide significant diagnostic clues to differentiate early Perthes' from transient synovitis

Introduction: Physical challenges and a long term treatment for Perthes disease can affect patients’ behaviour in their adolescence. We carried out a study to assess the long term psychosocial development of children treated non-operatively using abduction cast and brace. Methodology: 104 patients treated for Perthes disease between 1992 and 2001 were recruited for a retrospective study. Besides clinical review, patients and their main carers were asked to fill in Strengths and Difficulties Questionnaires (SDQ). SDQ included scores for total difficulties, emotional symptoms, conduct problems, hyperactivity, peer problems, social behaviour and total impact. 70 controls, matched for age and sex, attending the clinics for other unrelated pathology were requested to fill in the same questionnaires along with their main carers. Results: Data from 91 patients was available for assessment. Age at diagnosis was 1.9 to 7.3 years (median 3.9 years). Follow-up duration was 5.6 to 15.1 years (median 8.7 years). The age of subjects at final follow up was 8.9 to 20.4 years (median 15.3 years). The mean duration of treatment in abduction cast or brace was 2.4 years. 57 controls and 69 subjects were found to be low risk for emotional disorder (p> 0.05). Similarly 58 control and 74 subjects were predicted to be low risk for behavioural disorder. 16 controls and 18 subjects had medium or high risk for hyperactivity or concentration disorder (p> 0.05; student t test). There was no significant difference between the self report and parent questionnaires for difficulties or their impact. Conclusion: Perthes disease and the resultant restricted physical activities in early childhood does not affect the emotional and mental well being of patients in a long term

Objective. The relationship between the index (2D) to ring finger (4D) is one of the most commonly studied anthropometric measures, which is believed to offer insight into early growth and the foetal environment. This study aimed to determine the relationship between the 2D:4D ratio and the risk of Perthes' disease in children. Methods. The 2D:4D ratio was measured in 144 cases of Perthes' disease, and 144 controls. Cases and controls were frequency matched for age and sex. Measurements were recorded using a digital venier calliper on the palmar surface of the hand. Logistic regression was undertaken adjusting for age, with stratification for sex. Results. There was a significant negative association between Perthe's disease and digit ration in the right hand in affected females OR −0.78 (95% CI 0.65 – 0.93). There was no such association in males 0.97 (0.90 – 1.05). Conclusions. There is a significant association between degree of ‘masculinisation’ and Perthes' disease. This adds evidence to suggest that a significant aetiological component in disease acts prenatally, and may begin to explain the preponderance of disease amongst males

The radiographs of 153 children suffering from Perthes' disease of one hip were studied to examine the bony outline of the femoral capital epiphysis in the unaffected hip. In 48.4 per cent of patients irregularity of the surface, flattening or dimpling, were noted; in the majority of instances (37.2 per cent) these changes were present in the initial anteroposterior radiograph. By contrast, these changes were present in only 10.4 per cent of a control series of 153 children in whom intravenous urography was being performed, these children being matched for age and sex with the children with Perthes' disease. A second unmatched control series of 49 children whose pelves were being radiographed after injury showed a 6.1 per cent incidence of contour irregularities in 98 femoral capital epiphyses. In the patients with Perthes' disease and in the control series obtained at urography the incidence of changes was inversely related to age. The possible cause and significance of contour irregularities in normal children and in those with Perthes' disease is disscussed

There is a high incidence of Perthes' disease among the children of unskilled manual workers in underprivileged urban areas in Britain. The skeletal measurements of 38 Liverpool children with Perthes' disease were compared with those of their siblings and of normal children from the inner and outer city. Children in families where Perthes' disease occurs have retarded growth of the trunk, with reduced sitting height and bi-acromial diameter. Among those who develop the disease there is also retarded limb growth, most evident as unusually small feet

Perthes' disease is common in certain urban areas within Britain. It is one manifestation of a generalised growth disorder and nutritional causes are suspected. Orthopaedic surgeons throughout the Yorkshire region recorded all new patients with Perthes' disease over two years. There were large geographical differences in incidence which could not be explained by urban-rural or social class differences. No cases were recorded in a large area within the eastern part of the region, which is in high-grade farming land and has had a relatively low infant mortality throughout this century