Aims. Hip disease is common in children with cerebral palsy (CP) and can decrease quality of life and function. Surveillance programmes exist to improve outcomes by treating hip disease at an early stage using radiological surveillance. However, studies and surveillance programmes report different radiological outcomes, making it difficult to compare. We aimed to identify the most important radiological measurements and develop a core measurement set (CMS) for clinical practice, research, and surveillance programmes. Methods. A systematic review identified a list of measurements previously used in studies reporting radiological hip outcomes in children with CP. These measurements informed a two-round Delphi study, conducted among orthopaedic surgeons and specialist physiotherapists. Participants rated each measurement on a nine-point Likert scale (‘not important’ to ‘critically important’). A consensus meeting was held to finalize the CMS. Results. Overall, 14 distinct measurements were identified in the systematic review, with Reimer’s migration percentage being the most frequently reported. These measurements were presented over the two rounds of the Delphi process, along with two additional measurements that were suggested by participants. Ultimately, two measurements, Reimer’s migration percentage and femoral head-shaft angle, were included in the CMS. Conclusion. This use of a minimum standardized set of measurements has the potential to encourage uniformity across hip surveillance programmes, and may streamline the development of tools, such as artificial intelligence systems to automate the analysis in surveillance programmes. This core set should be the minimum requirement in clinical studies, allowing clinicians to add to this as needed, which will facilitate comparisons to be drawn between studies and future meta-analyses. Cite this article: Bone Jt Open 2023;4(11):825–831

Aims. The reduction in mobility due to hip diseases in children is likely to affect their physical activity (PA) levels. Physical inactivity negatively influences quality of life and health. Our aim was to objectively measure PA in children with hip disease, and correlate it with the Patient-Reported Outcomes Measurement Information System (PROMIS) Mobility Score. Methods. A total of 28 children (12 boys and 16 girls) with hip disease aged between 8and 17 years (mean 12 (SD 3)) were studied between December 2018 and July 2019. Children completed the PROMIS Paediatric Item Bank v. 2.0 – Mobility Short Form 8a and wore a hip accelerometer (ActiGraph) for seven consecutive days. Sedentary time (ST), light PA (LPA), moderate to vigorous PA (MVPA), and vigorous PA were calculated from the accelerometers' data. The PROMIS Mobility score was classified as normal, mild, and moderate functions, based on the PROMIS cut scores on the physical function metric. A one-way analysis of covariance (ANCOVA) was used to assess differences among mobility (normal; mild; moderate) and measured PA and relationships between these variables were assessed using bivariate Pearson correlations. Results. Children classified as normally functioning on the PROMIS had less ST (p = 0.002), higher MVPA, (p = 0.002) and VPA (p = 0.004) compared to those classified as mild or moderate function. A moderate correlation was evident between the overall PROMIS score and daily LPA (r = 0.462, n = 28; p = 0.013), moderate-to-vigorous PA (r = 0.689, n = 28; p = 0.013) and vigorous PA (VPA) (r = 0.535, n = 28; p = 0.013). No correlation was evident between the mean daily ST and overall PROMIS score (r = -0.282, n = 28; p = 0.146). Conclusion. PROMIS Pediatric Mobility tool correlates well with experimentally measured levels of physical activity in children with hip disease. We provide external validity for the use of this tool as a measure of physical activity in children. Cite this article: Bone Joint J 2021;103-B(2):405–410

Aims. The Patient-Reported Outcomes Measurement Information System (PROMIS) has demonstrated faster administration, lower burden of data capture and reduced floor and ceiling effects compared to traditional Patient Reported Outcomes Measurements (PROMs). We investigated the suitability of PROMIS Mobility score in assessing physical function in the sequelae of childhood hip disease. Methods. In all, 266 adolscents (aged ≥ 12 years) and adults were identified with a prior diagnosis of childhood hip disease (either Perthes’ disease (n = 232 (87.2%)) or Slipped Capital Femoral Epiphysis (n = 34 (12.8%)) with a mean age of 27.73 years (SD 12.24). Participants completed the PROMIS Mobility Computer Adaptive Test, the Non-Arthritic Hip Score (NAHS), EuroQol five-dimension five-level questionnaire, and the Numeric Pain Rating Scale. We investigated the correlation between the PROMIS Mobility and other tools to assess use in this population and any clustering of outcome scores. Results. There was a strong correlation between the PROMIS Mobility and other established PROMs; NAHS (rs = 0.79; p < 0.001). There was notable clustering in PROMIS at the upper end of the distribution score (42.5%), with less seen in the NAHS (20.3%). However, the clustering was broadly similar between PROMIS Mobility and the comparable domains of the NAHS; function (53.6%), and activity (35.0%). Conclusion. PROMIS Mobility strongly correlated with other tools demonstrating convergent construct validity. There was clustering of physical function scores at the upper end of the distributions, which may reflect truncation of the data caused by participants having excellent outcomes. There were elements of disease not captured within PROMIS Mobility alone, and difficulties in differentiating those with the highest levels of function. Cite this article: Bone Jt Open 2021;2(12):1089–1095

Our understanding of pre-arthritic hip disease has evolved tremendously but challenges remain in categorizing diagnosis, which ultimately impacts choice of treatments and clinical outcomes. This study aims to report patient reported outcome measures (PROMs) comparing four different condition groups within hip preservation surgery by a group of fellowship-trained surgeons. From 2018 to 2021, 380 patients underwent hip preservation surgery at our center and were classified into five condition groups: dysplasia: 82 (21.6%), femoro-acetabular impingement (FAI): 173 (45.4%), isolated labral tear: 103 (27.1%), failed hip preservation: 20 (5.3%) and history of childhood disease/other: 2 (0.5%). International hip outcomes Tool 12 (IHOT-12), numeric pain score and patient-reported outcomes measurement information system (PROMIS) were collected pre-operatively and at 3 months and 1 year post-operatively, with 94% and 82% follow-up rate respectively. Arthroscopy (75.5%) was the most common procedure followed by peri-acetabular osteotomy (PAO) (22.4%) and surgical dislocation (2.1%). Re-operation rate were respectively 18.3% (15), 5.8% (10), 4.9% (5), 30% (6) and 0%. There were 36 re-operations in the cohort, 14 (39%) for unintended consequences of initial surgery, 10 (28%) for mal-correction leading to a repeat operation, 8 (22%) progression of arthritis, and 4 (11%) for incorrect initial diagnosis/intervention. Most common re-operations were hardware removal 31% (7 PAO, 3 surgical hip dislocation and 1 femoral de-rotational osteotomy), arthroscopy 31% (11) and arthroplasty 28% (10). All groups had significant improvements in their IHOT-12 as well as PROMIS physical and numerical pain scales, except those with failed hip preservation. Dysplasia group showed a slower recovery. Overall, this study demonstrated a clear relation between the condition groups, their respective intervention and the significant improvements in PROMs with isolated labral pathology being a valid diagnosis. Establishing tertiary referral centers for hip preservation and longer follow-up is needed to monitor the overall survivorship of these various procedures

Aims. Lateral femoral cutaneous nerve (LFCN) injury is a complication after periacetabular osteo-tomy (PAO) using an anterior approach, which might adversely affect the outcome. However, no prospective study has assessed the incidence and severity of this injury and its effect on the clinical outcomes over a period of time for longer than one year after PAO. The aim of this study was to assess the incidence and severity of the symptoms of LFCN injury for ≥ three years after PAO and report its effect on clinical outcomes. Methods. A total of 40 hips in 40 consecutive patients who underwent PAO between May 2016 and July 2018 were included in the study, as further follow-up of the same patients from a previous study. We prospectively evaluated the incidence, severity, and area of symptoms following LFCN injury. We also recorded the clinical scores at one year and ≥ three years postoperatively using the 36-Item Short Form Health Survey (SF-36) and Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) scores. Results. A total of 20 patients (50%) had symptoms of a LFCN injury at one year after PAO. At ≥ three years postoperatively, the symptoms had completely resolved in seven of these patients and 13 (33%) had persistent symptoms. The severity and area of symptoms did not significantly differ between one and ≥ three years postoperatively. The JHEQ showed significant differences in the patient satisfaction and mental scores between those with and those without sypmtoms of LFCN injury at ≥ three years postoperatively, while there was no significant difference in the mean SF-36 scores. Conclusion. The incidence of LFCN injury after PAO using an anterior approach is high. The outcome of PAO, ≥ three years postoperatively, is poorer in patients with persistent symptoms from a perioperative LFCN injury, in that patient satisfaction and mental health scores are adversely affected. Cite this article: Bone Joint J 2024;106-B(5 Supple B):11–16

Aims. Lateral femoral cutaneous nerve (LFCN) injury is a potential complication after the direct anterior approach for total hip arthroplasty (DAA-THA). The aim of this study was to determine how the location of the fasciotomy in DAA-THA affects LFCN injury. Methods. In this trial, 134 patients were randomized into a lateral fasciotomy (n = 67) or a conventional fasciotomy (n = 67) group. This study was a dual-centre, double-blind, prospective randomized controlled two-arm trial with parallel group design and a 1:1 allocation ratio. The primary endpoint was the presence of LFCN injury, which was determined by the presence of numbness, decreased sensation, tingling, jolt-like sensation, or pain over the lateral aspect of the thigh, excluding the surgical scar, using a patient-based questionnaire. The secondary endpoints were patient-reported outcome measures (PROMs) using the Western Ontario and McMaster Universities osteoarthritis index (WOMAC), Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ), and the Forgotten Joint Score-12 (FJS-12). Assessments were obtained three months after surgery. Results. The incidence of LFCN injury tended to be lower in the lateral fasciotomy group (p = 0.089). In the lateral fasciotomy group, there were no significant differences in the mean PROM scores between patients with and without LFCN injury (FJS-12: 54.42 (SD 15.77) vs 65.06 (SD 26.14); p = 0.074; JHEQ: 55.21 (SD 12.10) vs 59.72 (SD 16.50); p = 0.288; WOMAC: 82.45 (SD 6.84) vs 84.40 (SD 17.91); p = 0.728). In the conventional fasciotomy group, there were significant differences in FJS-12 and JHEQ between patients with and without LFCN injury (FJS-12: 43.21 (SD 23.08) vs 67.28 (SD 20.47); p < 0.001; JHEQ: 49.52 (SD 13.97) vs 59.59 (SD 15.18); p = 0.012); however, there was no significant difference in WOMAC (76.63 (SD 16.81) vs 84.16 (SD 15.94); p = 0.107). Conclusion. The incidence of LFCN injury at three months after THA was comparable between the lateral and conventional fasciotomy groups. Further studies are needed to assess the long-term effects of these approaches. Cite this article: Bone Joint J 2023;105-B(12):1252–1258

Introduction. Most of patients with unilateral hip disease shows muscle volume atrophy of pelvis and thigh in the affected side because of pain and disuse, resulting in reduced muscle weakness and limping. However, it is unclear how the muscle atrophy correlated with muscle strength in the patient with hip disorders. A previous study have demonstrated that the volume of the gluteus medius correlated with the muscle strength by volumetric measurement using 3 dimensional computed tomography (3D-CT) data, however, muscles influence each other during motions and there is no reports focusing on the relationship between some major muscles of pelvis and thigh including gluteus maximus, gluteus medius, iliopsoas and quadriceps and muscle strength in several hip and knee motions. Therefore, the purpose of the present study is to evaluate the relationship between muscle volumetric atrophy of major muscles of pelvis and thigh and muscle strength in flexion, extension and abduction of hip joints and extension of knee joint before surgery in patients with unilateral hip disease. Material and Methods. The subjects were 38 patients with unilateral hip osteoarthritis, who underwent hip joint surgery. They all underwent preoperative computed tomography (CT) for preoperative planning. There were 6 males and 32 females with average age 59.5 years old. Before surgery, isometric muscle strength in hip flexion, hip extension, hip abduction and knee extension were measured using a hand held dynamometer (µTas F-1, ANIMA Japan). Major muscles including gluteus maximus, gluteus medius, iliopsoas and quadriceps were automatically extracted from the preoperative CT using convolutional neural networks (CNN) and were corrected manually by the experienced surgeon. The muscle volumetric atrophy ratio was defined as the ratio of muscle volume of the affected side to that of the unaffected side. The muscle weakness ratio was defined as the ratio of muscle strength of the affected side to that of the unaffected side. The correlation coefficient between the muscle atrophy ratio and the muscle weakness ratio of each muscle were calculated. Results. The average muscle atrophy ratio was 84.5% (63.5%–108.2%) in gluteus maximus, 86.6% (65.5%–112.1%) in gluteus medius, 81.0% (22.1%–130.8%) in psoas major, and 91.0% (63.8%–127.0%) in quadriceps. The average muscle strength ratio was 71.5% (0%–137.5%) in hip flexion, 88.1% (18.8%–169.6%) in hip abduction, 78.6% (21.9%–130.1%) in hip extension and 84.3% (13.1%–122.8%) in knee extension. The correlation coefficient between the muscle atrophy and the ratio of each muscle strength between the affected and unaffected side were shown in Table 1. Conclusion. In conclusion, the muscle atrophy of gluteus medius muscle, psoas major muscle and quadriceps muscle significantly correlated with the muscle weakness in hip flexion. The muscle atrophy of psoas major muscle and quadriceps muscle also significantly correlated with the muscle weakness in knee extension. There were no significant correlation between the muscle atrophy and the muscle weakness in hip extension and abduction

We studied the effect of trochanteric osteotomy in 192 total hip replacements in 140 patients with congenital hip disease. There was bony union in 158 hips (82%), fibrous union in 29 (15%) and nonunion in five (3%). The rate of union had a statistically significant relationship with the position of reattachment of the trochanter, which depended greatly on the pre-operative diagnosis. The pre-operative Trendelenburg gait substantially improved in all three disease types (dysplasia, low and high dislocation) and all four categories of reattachment position. A persistent Trendelenburg gait post-operatively was noticed mostly in patients with defective union (fibrous or nonunion). Acetabular and femoral loosening had a statistically significant relationship with defective union and the position of reattachment of the trochanter. These results suggest that the complications of trochanteric osteotomy in total hip replacement for patients with congenital hip disease are less important than the benefits of this surgical approach

Introduction: In the Swedish health care system waiting time for THR surgery has been unacceptable long. There are several hip disease related circumstances that generates costs for the society and the patient. In order to perform complete health economic analysis these costs have to be assessed. Patients and Material: Prior to THR surgery, 3500 patients from 20 hospitals were asked to complete a questionnaire regarding cost generating events related to the hip disease. Individual data on waiting time were collected. Follow-up questionnaire was administered one year postoperatively. Preliminary results: 2712 patients answered the pre-operative questionnaire. The sample was representative; mean age 69 years, 67% > 65 years (retirement age). Mean waiting time for orthopaedic consultation was 176 days and for surgery 312 days. 82% used any medication due to the hip disease. Among the non-retired patients 33% were on sick leave and 25% were on disability pension. 4% reported home-help service, 9% transportation service for disabled, and 46% had any home modification. 26% required help from relatives in various extents. The costs related to hip disease amounts to 8 000 Euro one year prior to surgery. Productivity loss constitutes 72% of total costs, health care costs 13%, municipal costs 6%, medication 1,5% and costs for relative care-taking 7,5%. Discussion: Productivity loss constitutes the principal cost for hip disease in patients eligible for THR surgery. One year on the waiting list costs equals the surgery cost. The waiting time for orthopaedic consultation and subsequent surgery is unacceptable long. Baseline cost data is important for further adequate health economic analyses

This paper reviews the current knowledge relating to the management of adult patients with congenital hip disease. Orthopaedic surgeons who treat these patients with a total hip replacement should be familiar with the arguments concerning its terminology, be able to recognise the different anatomical abnormalities and to undertake thorough pre-operative planning in order to replace the hip using an appropriate surgical technique and the correct implants and be able to anticipate the clinical outcome and the complications

Purpose: The outcome of primary total hip arthroplasty (THA) after a previous paediatric hip disease was studied in data from the Norwegian Arthroplasty Register (NAR). Materials and Methods: 72,301 primary THAs were reported to the NAR for the period 1987 – February 2002. Of these, 5,459 (7.6%) were performed because of sequela after developmental dysplasia of hip (DDH), 737 (1.0%) because of DDH with dislocation, 961 (1.3%) because of Perthes’/ slipped femoral capital epiphysis (SFCE) and 50,369 (70%) because of primary osteoarthritis (OA). Prosthesis survival was calculated by the Kaplan-Meier method and relative risks for revision in a Cox model with adjustments for age, gender, type of systemic antibiotic, operation time, type of operating theatre and brand of prosthesis. Results: Without any adjustments the THAs for all three groups of paediatric hip diseases had 1.4 – 2.0 times increased risk for revision compared to that of OA (p< 0.001). Due to huge differences in the studied groups, a more homogenous subset of the data had to be analysed. In this subset, only THAs with well documented prostheses, high-viscosity cements and antibiotic prophylaxis both systemically and in the cement were included (16,874 THAs). In this homogenous subset, no differences in the survivals could be detected for DDH without dislocation and for Perthes’/SFCE compared to OA. For DDH with dislocation the revision risk with all reasons for revisions as endpoint in the analyses was increased 3.3 times compared to OA (p< 0.001), 2.7 times with aseptic loosening as endpoint (p< 0.01) and 10 times with infection as endpoint (p< 0.001). Conclusions: If well-documented THAs are used after paediatric hip diseases the results are just as good as after osteoarthritis, except for DDH with dislocation where increased revision risk is found

The diagnosis and treatment of hip disease in young adults has rapidly evolved over the past ten years. Despite the advancements of improved diagnostic skills and refinement of surgical techniques, the psychosocial impact hip disease has on the young adult has not yet been elucidated. This observational study aimed to characterise the functional and psychosocial characteristics of a group of patients from our young hip clinic. 49 patients responded to a postal questionnaire which included the Oswestry Disability Index (ODI) and Hospital Anxiety and Depression Scale (HADS). Median age was 20 years (range 16-38) with a gender ratio of 2:1 (female: male). The most common diagnoses were Perthes' disease and developmental hip dysplasia. More than half of our patients had moderate to severe pain based on the Visual Analogue Scale (VAS) and at least a moderate disability based on the ODI. Thirty-two percent of patients were classified as having borderline to abnormal levels of depression and 49% of patients were classified as having borderline to abnormal levels of anxiety based on the HADS. Comparison of the ODI with the VAS and HADS anxiety and depression subscales showed a significant positive correlation (p<0.05). Multiple regression showed the ODI to be a significant predictor of the HADS anxiety and depression scores (regression coefficient 0.13, 95% confidence interval 0.06 to 0.21, p<0.05). This study highlights the previously unrecognised psychosocial effects of hip disease in the young adult. A questionnaire which includes HADS may be of particular value in screening for depression and anxiety in young people with physical illness. This study also highlights that collaboration with psychologists and other health care providers may be required to achieve a multidisciplinary approach in managing these patients

We have evaluated the results of total hip replacement in patients with congenital hip disease using 46 cemented all-polyethylene Charnley acetabular components implanted with the cotyloplasty technique in 34 patients (group A), and compared them with 47 metal-backed cementless acetabular components implanted without bone grafting in 33 patients (group B). Patients in group A were treated between 1988 and 1993 and those in group B between 1990 and 1995. The mean follow-up for group A was 16.6 years (12 to 18) and the mean follow-up for group B was 13.4 years (10 to 16). Revision for aseptic loosening was undertaken in 15 hips (32.6%) in group A and in four hips (8.5%) in group B. When liner exchange was included, a total of 13 hips were revised in group B (27.7%). The mean polyethylene wear was 0.11 mm/yr (0.002 to 0.43) and 0.107 mm/yr (0 to 0.62) for groups A and B, respectively. Polyethylene wear in group A was associated with linear osteolysis, and in group B with expansile osteolysis. In patients with congenital hip disease, when 80% cover of the implant can be obtained, a cementless acetabular component appears to be acceptable and provides durable fixation. However, because of the type of osteolysis arising with these devices, early exchange of a worn liner is recommended before extensive bone loss makes revision surgery more complicated

Aims. To our knowledge, no study has compared the long-term results of cemented and hybrid total hip arthroplasty (THA) in patients with osteoarthritis (OA) secondary to congenital hip disease (CHD). This is a demanding procedure that may require special techniques and implants. Our aim was to compare the long-term outcome of cemented low-friction arthroplasty (LFA) and hybrid THA performed by one surgeon. Patients and Methods. Between January 1989 and December 1997, 58 hips (44 patients; one man, 43 woman; mean age 56.6 years (25 to 77)) with OA secondary to CHD were treated with a cemented Charnley LFA (group A), and 55 hips (39 patients; two men, 37 women; mean age 49.1 years (27 to 70)) were treated with a hybrid THA (group B), by the senior author (GH). The clinical outcome and survivorship were compared. Results. At all timepoints, group A hips had slightly better survivorship than those in group B without a statistically significant difference, except for the 24-year survival of acetabular components with revision for aseptic loosening as the endpoint, which was slightly worse. The survivorship was only significantly better in group A compared with group B when considering reoperation for any indication as the endpoint, 15 years postoperatively (74% vs 52%, p = 0.018). Conclusion. We concluded that there was not a substantial difference at almost any time in the outcome of cemented Charnley LFAs compared with hybrid THAs when treating patients with OA of the hip secondary to CHD. We believe, however, that after improvements in the design of components used in hybrid THA, this could be the method of choice, as it is technically easier with a shorter operating time. Cite this article: Bone Joint J 2019;101-B:1050–1057

Purpose of the study: Although the association between femoroacetabular impingement and degenerative hip disease has been well established, there is no way to detect a subgroup of hips with radiographic signs of impingement which will progress to degeneration. In addition, the majority of publications on the topic have been conducted in populations of patients with an overtly degenerative hip, where the incidence of signs of impingement is higher. There has not been any study searching for the presence of signs of impingement in a symptom free population. For this reason, we searched for signs of femoroacetabular impingement in a general population and attempted to find correlations with degenerative hip disease. Material and method: We examined 200 computed tomography (CT) series of the pelvis performed for reason other than an orthopaedic indication. Four hundred hips were thus analysed with the Amira 4.1 3D software. We measured the classical coxometric parameters, orientation of the acetabulum, alpha angle, and presence or not of a bulge at the head-neck junction. Cartilage thickness was also mapped using a precise protocol. Cartilage thickness less than 0.25mm was considered for the purpose of this study to indicate degenerative disease. All data were processed with SPPS 17.0. Results: There were 103 men and 97 women, mean age 58 years and 59 years respectively. The mean alpha angle was 55.7. Retroversion was noted in 20% of hips and 28% exhibited an anterior bulge at the head-neck junction. The mean cartilage thickness at the anterosuperior part of the hip was 37mm. Degenerative disease was present in 28 patients (14%) whose mean cartilage thickness at the anterosuperior portion of the joint was 21 mm. There was no significant correlation between cartilage thickness and acetabular orientation, alpha angle, presence of a bulge at the head-neck junction. Only age was significantly correlated with degenerative disease r=−0.158 [p< 0.0]. Discussion: Among the parameters currently considered to be risk factors for degenerative disease of the hip joint, age alone was statistically linked with reduced cartilage thickness in our symptom-free population. This would suggest that the essential mechanism underlying degenerative disease remains to be discovered. Conclusion: Our findings suggest we should be prudent when proposing corrective surgery for femoroacetabular impingement. Such surgery should be reserved for symptomatic patients

We studied the rates of revision for 53 698 primary total hip replacements (THRs) in nine different groups of disease. Factors which have previously been shown to be associated with increased risk of revision, such as male gender, young age, or certain types of uncemented prosthesis, showed important differences between the diagnostic groups. Without adjustment for these factors we observed an increased risk of revision in patients with paediatric hip diseases and in a small heterogeneous ‘other’ group, compared with patients with primary osteoarthritis. Most differences were reduced or disappeared when an adjustment for the prognostic factors was made. After adjustment, an increased relative risk (RR) of revision compared with primary osteoarthritis was seen in hips with complications after fracture of the femoral neck (RR = 1.3, p = 0.0005), in hips with congenital dislocation (RR = 1.3, p = 0.03), and in the heterogenous ‘other’ group. The analyses were also undertaken in a more homogenous subgroup of 16 217 patients which had a Charnley prosthesis implanted with high-viscosity cement. The only difference in this group was an increased risk for revision in patients who had undergone THR for complications after fracture of the femoral neck (RR = 1.5, p = 0.0005). THR for diagnoses seen mainly among young patients had a good prognosis, but they had more often received inferior uncemented implants. If a cemented Charnley prosthesis is used, the type of disease leading to THR seems in most cases to have only a minor influence on the survival of the prosthesis

Aims

Although the short stem concept in hip arthroplasty procedure shows acceptable clinical performance, we sometimes get unexplainable radiological findings. The aim of this retrospective study was to evaluate changes of radiological findings up to three years postoperatively, and to assess any potential contributing factors on such radiological change in a Japanese population.

Aims: To assess the influence of hip disease on the risk of revision, we studied different disease groups among 53 698 primary total hip replacements (THRs) reported to the NAR between 1987 and 1999. Methods: the revision rate in the 8 most common hip diseases were compared by kaplan-meier survival analyses and cox multiple-regression. To eliminate the influence of prosthesis type a subgroup of 16217 charnley prostheses were analysed. Results: we found statistically significant differences in prosthesis survival among the hip diseases, but after adjustment for prosthesis type most of the differences disappeared. In patients ≤60 years, 59% of the prostheses were uncemented and 33% could be defined as inferior uncemented prostheses. In the charnley subgroup only complications after fracture of the femoral neck had an increased risk for revision compared to primary osteoarthritis (rr 1.5, p=0.005). 10 years survival for cemented charnley prostheses with osteoarthritis was 92.0% for patients ≤60 years and 93.5% for patients > 60 years. Conclusions: after adjustment the results for all disease groups were good. The results of thrs in disease-groups where patients are operated on at a young age were less good because these patients had often been given inferior uncemented prostheses

Objective: To review our results with hip joint reconstruction in severe spastic hip disease. Design: Descriptive case series. Setting: A tertiary referral medical center. Subjects: All the patients who underwent a hip reconstruction procedure because of SHD were retrospectively evaluated. Twenty-five patients with 32 involved femoral necks were treated between 1997 and 2003. All of the patients had a migration index greater than 40% with 8 of them having a migration index of over 65%. 15 patients had total involvement type CP and 10 patients had diplegic type CP. Intervention: Hip joint reconstruction comprised of varus derotation osteotomy and a periacetabular osteotomy such as the Dega osteotomy, and when necessary an open reposition of the hip joint was performed. Results: Good coverage of the femoral head was achieved in 23 of the patients and in 30 of the femoral heads. There was no difference between the high migration index group and the low migration index group. In two cases progressive posterior dislocation continued following the operation, attributed to incomplete correction of the posterior acetabulum. One patient had an intra-operative fracture of the femoral neck. The results were similar in the more severe and less severe groups. Conclusions: Hip reconstruction has favorable results in all types of CP. We found no difference between the group with high migration index and the low migration index concerning complications and outcome. A high migration index should not be considered as reason not to reconstruct the hip joint. The only contraindication for this procedure is osteoarthritic changes of the hip joint

Introduction. Patients presenting with osteoarthritis as late sequelae following pediatric hip trauma have few options aside from standard Total Hip Replacement (THR). For younger more active patients, Hip Resurfacing Arthroplasty (HRA) can be offered as an alternative. HRA has been performed in the United States over the past decade and allows increased bone preservation, decreased hip dislocation rates versus THR, and potential to return to full activities. Patients presenting with end-stage hip arthritis as following prior pediatric trauma or disease often have altered hip morphology making HRA more complicated. Often Legg-Calve-Perthes (LCP) patients present with short, wide femoral necks, and femoral head distortion including coxa magna or coxa plana. There often can be acetabular dysplasia in conjunction with the proximal femoral abnormalities. Slipped Capital Femoral Epiphysis (SCFE) patients have an alteration of the femoral neck and head alignment, which can make reshaping the femoral head difficult. In particular, the femoral head is rotated medially and posteriorly, reducing the anterior and lateral offset. We present a cohort of 20 patients, with history of a childhood hip disorder (SCFE or LCP), who underwent HRA to treat end-stage arthritis. Fifty percent had prior pediatric surgical intervention at an average age of 11. Method. After Institutional Review Board approval, data was reviewed retrospectively on patients with pediatric hip diseases of SCFE and LCP who underwent HRA using the Birmingham Hip Resurfacing (BHR) by a single orthopaedic surgeon at a teaching institution. Harris Hip Scores (HHS), plain radiographs and blood metal ion levels were reviewed at routine intervals (12 months and annually thereafter). Those who had not returned for recent follow-up were contacted via telephone survey for a modified HHS. Results. Twenty patients had mean follow up of 2.8 years (range 1–7 years). Twelve had LCP and 8 SCFE. Median implant duration was 2.4 years. One-year metal ion testing revealed median chromium level of 2.3 ppb and median Cobalt level of 1.5 ppb. At one-year follow up, plain radiographs demonstrated all patient implants to be well-fixed, without radiolucent lines or osteolysis. Two patients at three and five-year follow-up exhibited heterotopic ossification. Mean HHS for LCP at 6 weeks post-operative was 88, and 98 at one year. Mean HHS for SCFE at 6 weeks post-operative was 77.5, and 98.6 at one year. LLD was significantly improved with an average pre-operative LLD of 12.6 mm and post op of 2.6 mm (p-value <0.001). At most recent follow-up, all retained their implants with overall average HHS of 98. Conclusion. At minimum of one-year following HRA, an increase in functional outcomes is found in patients who underwent HRA for osteoarthritis associated with LCP and SCFE with a mean HHS of 98. No increase was found in complications including femoral neck fracture or implant loosening despite technical challenges of the procedure related to proximal femoral morphologic abnormalities, or presence of acetabular dysplasia [Fig 1]