Aims

The aim of this study was to estimate the clinical and economic burden of dislocation following primary total hip arthroplasty (THA) in England.

Low energy hip dislocation in children is an uncommon injury (0.335% of injuries ) which represents a true orthopaedic emergency. Case 1 ; A 6 year old girl attended hospital non-weightbearing with right thigh pain after slipping whilst attempting to kick a football. The leg was shortened and internally rotated with no neurovascular deficit. Radiographs revealed a posterior dislocation of the right hip. A closed reduction was undertaken in theatre within four hours. She was immobilised in a hip spica for 6 weeks. At six month review she was pain free and back to full activities. Radiographs showed no abnormality. Case 2 ; A 5 year old boy attended A+E non-weight-bearing with right lower leg and knee pain having done the splits playing football. Examination of knee and lower leg showed pain but nil else. Radiographs of the knee were normal. He was discharged with a diagnosis of possible ACL rupture. He re-attended 2 days later with immobility and increasing pain. Examination showed a 2cm leg length discrepancy. Radiographs revealed a posterior hip dislocation. He underwent a closed reduction in theatre. He progressed well under regular review until 5 months post-injury. He had increasing pain and decreasing range of movement. Radiographs showed trans-epiphyseal avascular necrosis. He therefore underwent a varus de-rotation osteotomy. One year on he has returned to full activities. He has a mild decreased range of movement. Radiographs show a flattened epiphysis and a united osteotomy. Hip dislocation requires less trauma in children due to ligamentous laxity and a soft pliable acetabulum. Overall 64% are low energy and 80% are posterior dislocations. Complications include AVN, arthritis, nerve palsy and recurrent dislocation. AVN is 20 times more common if reduction is after 6 hours. This report highlights the importance of thorough examination, accurate diagnosis and early treatment of paediatric hip dislocation

Children with cerebral palsy (CP) have an increased risk of progressive hip displacement. While the cause of hip displacement remains unclear, spasticity and muscle imbalance around the hip are felt to be a major factor. There is strong evidence demonstrating that a selective dorsal rhizotomy (SDR) reduces spasticity. However, the impact of this decreased spasticity on hip displacement is unknown. Past studies, which are small and lack long-term follow-up, do not provide a clear indication of the effect of SDR on hip displacement. The purpose of this study was to determine the influence of SDR on hip displacement in children with CP a minimum of five years post-SDR. A retrospective chart review was completed. Participants were selected from a consecutive series of children who had an SDR before January 1, 2013 at one tertiary care facility to ensure a minimum five year follow-up. Pre-operative and minimum five year post-SDR AP pelvis radiographs were required for inclusion. Hip displacement was evaluated using change in MP between radiographs completed pre-SDR and minimum five years post-SDR, or until orthopaedic hip surgery. In total, 77 participants (45 males, 32 females) at GMFCS levels of I (1), II (11), III (22), IV (35) and V (8) were included in the review. Mean age at time of SDR was 5 years (2.8– 11.6yrs). Pre-SDR mean MP of the 154 hips was 29% (0–100%). Post-SDR, 67 (43.5%) hips in 35 children had soft tissue, reconstructive, or salvage hip procedures at an average of 4.9 years (0.5–13.8yrs) post-SDR and an average MP of 46% (11–100%). In addition, seven hips (5%) had a MP ≥ 40% (40–100%) at most recent radiographic review that averaged 11 years (5.6–18.6yrs). Overall, the total number of subjects with hip displacement measuring MP >40% or who had a surgical hip intervention, by GMFCS level, was: 0 (0%) at level I, 0 (0%) at level II, 20 (45%) at level III, 22 (59%) at level IV, and 5 (81%) at level V. The incidence of hip displacement in children with CP post-SDR did not substantially differ from the overall incidence reported in the literature when evaluated by GMFCS level. This study is the largest long-term follow-up study investigating the effect of hip displacement post-SDR. Results suggest that SDR does not impact hip displacement in CP, however, further prospective study will be required to strengthen the evidence in this regard

Total Hip Arthroplasty (THA) and Hip Hemiarthroplasties (HA) are successful, cost-effective procedures that improve quality of life. Dislocation is a well recognised complication with a significant health and economic burden. We aim to establish the current management practices across the United Kingdom (UK) for Prosthetic Hip Dislocations (PHD). Our definition of a PHD includes; THA, HA and revision THA. This national study builds on our regional pilot study and records one of the largest datasets of Prosthetic Hip Dislocation management within the UK. A trainee-led collaborative; the North West Orthopaedic Research Collaborative (NWORC). Conducted a retrospective audit, registered as Quality Improvement (QI) projects, collected data from 38 hospital trusts across the UK. Data was collected on patient-related factors, inpatient management, and outpatient follow up of each PHD episode between January and July 2019. Primary outcome measured definitive management, in the form of revision surgery or the consideration for this through a referral pathway. A total of 673 (THA 504, Revision THA 141, HA 28) patients were included with a total of 740 dislocation episodes. Mean age was 75.6 years with female to male ratio 2:1. The majority of PHDs were a result of a low energy mechanism (98.7%) and presented over 6 months post index procedure (80.5%). Over half (53.8%) attended with a first or second time dislocation. Only 29.9% patients received onward revision referral; whereas 70.1% followed diverse management patterns, including local non-arthroplasty and primary arthroplasty surgeon follow-ups. Revision THAs had higher rates of referral for revision (p<0.001) compared to primary THA and HA dislocations. A high number of PHDs present across the UK, with under a third receiving definitive management plans. This variation increases the economical burden to the National Health Service, highlighting the need for national guidance to manage these complex patients

To estimate the clinical and economic burden of primary total hip arthroplasty (THA) dislocation in England. Retrospective propensity score-matched evaluation of patients with and without dislocation following primary THA using the UK Clinical Practice Research Datalink linked and Hospital Episode Statistics datasets with a 2-year follow-up. 13,044 patients with total hip replacements met the inclusion criteria (mean age 69.2, 60.9% female) of which 154 (1.18%) suffered at least one postoperative hip dislocation. The mean number of dislocations per patient was 1.44 with a maximum of 4. Approximately one-third of the patients with dislocation (32.5%) had more than one dislocation. Among patients with a hip dislocation 148 patients (96.7%) had at least one closed reduction and 20 patients (13.1%) had revision surgery. Two-year median direct medical costs were £14,748 (95% confidence interval [CI] £12,028 to £20,638) higher with vs. without dislocation (+227%). On average, patients with a dislocation had significantly greater healthcare resource utilization and significantly less improvement in EuroQol-5D (EQ-5D) index (0.24 vs. 0.45; p<0.001) and Visual Analogue Scale (VAS) (1.58 vs. 11.23; p=0.010) scores and Oxford Hip Scores (13.02 vs. 21.98; p<0.001). This is the first study to estimate the economic burden of dislocation in the UK throughout the entire patient pathway. Dislocation following total hip replacement is a costly complication, both in terms of economic costs and to the functional quality of life of the patient. Efforts to reduce the risks of dislocation should remain at the forefront of hip research

Total Hip Replacements (THR) and Hip Hemiarthroplasties (HA) are both successful and common orthopaedic procedures. Dislocation is a well-recognised complication carrying significant morbidity and, in some cases, increased mortality risks. We define prosthetic hip dislocations (PHDs) to include both THRs and HAs. Prosthetic Hip Dislocations (PHDs) are a common acute admission yet there are no published guidelines or consensus on management following reduction. A retrospective audit was undertaken by the North West Orthopaedic Research Collaborative (NWORC) between January 2019 and July 2019. A questionnaire was used to capture the management of each dislocation episode presenting to 11 Hospital trusts. The study was registered as a Quality Improvement (QI) project at each site. Data regarding the surgical management physiotherapy input, ongoing care and further management plans were recorded. A total of 183 patients with 229 dislocations were submitted for initial analysis (171 THRs, 10 HAs, 2 PFRs). Female to male ratio was 2:1 with mean age of 76.7 years. Average time to first dislocation was 8.1 years. 61.1% were first or second time dislocators and 38.9% presented with 3 or more dislocations. Initial reductions were predominantly attempted in theatre (96.5%, n=221) with only 3.5% (n=8) attempted in the emergency department. In theatre 89% (n=201) were reduced closed. There was no plan for revision surgery in 70.6% cases with no difference seen between patients with >=3 dislocations and <=2 dislocations. Of the patients with a revision plan, 71% of these were performed or planned locally. The high number of patients with 3 or more dislocations and the lack of plans for definitive interventions in the majority of cases highlights the significant variation in the management of this complex group of patients. This variation in the quality of care increases the burden on the National Health Service through repeat hospital episodes. We aim to roll out this study nationally to assess regional variations and ultimately make the case for national guidance on the management of prosthetic hip dislocations

Introduction. The anatomic abnormalities are observed in developmental dysplasia of the hip (DDH) and it is challenging to perform the total hip arthroplasty (THA) for some DDH patients. If acetabular cup was placed at the original acetabular position in patients with high hip dislocation, it may be difficult to perform reduction of hip prosthesis because of soft tissue contracture. The procedures resolving this problem were to use femoral shortening osteotomy, or to place the acetabular cup at a higher cup position than the original hip center. Femoral shortening osteotomy has some concerns about its complicated procedure, time consuming, and risk of non-union. Conversely, implantation of the acetabular cup at the higher cup position may eliminate these shortcomings and this procedure is considered to be preferred if possible. However, the criteria of cases without femoral shortening osteotomy are not clear. In this study, we retrospectively analysed the clinical outcomes of patients performed THAs for high hip dislocation, and clarified the adaptation of THA with or without femoral shortening osteotomy. Methods. We included a total of 65 hip joints from 57 patients who underwent primary THA using Modulus stem for high hip dislocation from November 2007 to December 2015 at our institution. The mean follow up period was 5.2 years (2 – 10 years). The mean age at surgery was 65.4 years (Table 1). Thirty seven hips were classified as Crowe III, and twenty eight hips as Crowe IV based on Crowe classification. We classified patients into two groups based on the use of femoral osteotomy. Then, we compared the surgical time, blood loss, Japanese Orthopaedic Association (JOA) Score as clinical outcomes, preoperative position of the greater trochanter, the cup position, and complications between two groups. The position of the greater trochanter was measured the height of the tip of greater trochanter from the inter teardrop line. The cup center position was assessed by measuring the distance between the cup center and ipsilateral tear drop. Receiver operating characteristic (ROC) curves were plotted for deciding the cut-off value for the height of the greater trochanter. The cut-off value presented the maximum sensitivity and specificity was determined. Results and Discussion. Fifty three THAs were operated without femoral shortening osteotomy, and twelve THAs were performed with femoral shortening osteotomy. The surgical time was significantly longer in the osteotomy group than the non-osteotomy group. The mean height of the tip of the greater trochanter were 53.2±11.4mm in the non-osteotomy group and 92.2±19.7 mm in the osteotomy group (Table 2). The cut-off value of the height of greater trochanter evaluated from the ROC curve analysis was 69.5mm (Fig.1). There were no significant differences in clinical score between two groups. More ratio of revisions and fractures were observed in the osteotomy group with significant differences. Conclusion. There were significant differences in postoperative complications in osteotomy group compare to non-osteotomy group. In cases with a greater trochanter tip height of 69.5 mm or less, it may be considered to avoid femoral shortening osteotomy

Objective. To define the common pathology of the hips with irreducible posterior dislocation combined with femoral head fracture and the outcome of surgical treatment using surgical hip dislocation technique. Design: retrospective observational clinical study. Setting: Level III referral trauma center. Patients/Participants: from January 2011till February 2014 five patients with irreducible posterior hip dislocation and femoral head fracture who underwent operation were included and they followed for at least 18 months. Intervention. Open reduction and internal fixation of fractured femoral head and labral repair by suture anchors using surgical hip dislocation through trochanteric flip osteotomy approach. Main Outcome Measures: Clinical and radiographical findings of the irreducible posterior hip dislocation, intraoperative findings, clinical outcomes using Merle d'Aubigné & Postel and Thompson & Epstein scores, and radiological outcome. Results. All patients presented clinically with a shortened lower limb in neutral or external rotation of the hip (not in Internal rotation). All were Pipkin type II fracture of femoral head with the intact part of the head buttonholed on the posterior wall of the acetabulum through a capsule-labral flap. Postoperative computed tomography revealed perfect reduction except one case with severe comminution with good reduction. Only one patient with delayed operative management developed avascular necrosis and underwent total hip arthroplasty. Conclusion. Irreducible femoral head fracture-dislocation is rare injury with different clinical presentation that shows neutral or externally rotated limb and optimal surgical management is not clear. Surgical hip dislocation gives full access to the femoral head for reconstruction and opportunity to direct repair of the labral tears

Traumatic hip dislocation is a rare injury in orthopaedic practice and typically occures in high energy trauma. The goal of this study was to analyze hip morphology in patients with low energy traumatic hip dislocations and to compare it with a control group. We performed a retrospective comparative study. The study group included 45 patients with 45 traumatic posterior hip dislocation. Inclusion criteria were traumatic hip dislocation with simple acetabular rim or Pipkin I or II fracture. Traumatic dislocations combined with other acetabular or femoral fractures were excluded. The control group consisted of 90 patients (180 hips) that underwent radiographic examination for urogenital indication and had no history of hip pain. Hip morphology was assessed on antero-posterior and axial views. The study group showed significantly increased incidence (p<0.001) of positive cross-over sign (82% vs. 27%) with a increased retroversion index (26 ± 17 [0–56] vs. 6 ± 12 [0–53]), positive ischial spine sign (70% vs. 34%), and positive posterior wall sign (79% vs. 21). Hips that underwent an low energy posterior traumatic hip dislocation show significanly more radiographic signs for acetabular retroversion compared to a control group. Therefore, acetabular retroversion seems to be a contributing factor for posterior traumatic hip dislocation

To investigate the clinical results of capsular arthroplasty in the treatment of young patients with unilateral hip dislocation. We retrospectively evaluated all patients who had the capsular arthroplasty from June 2012 to September 2016 in our department. Hips were evaluated using hip Harris score (HHS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. The Tonnis osteoarthritis grade and Severin classification were used to access the radiographic outcomes. Fifty-nine patients (10 males and 49 females) with an average of 16.8y (range: 8–26y) were followed by a mean of 32.1 months (range: 12.5–66.0 months). The mean HHS was 83.4 (range: 31.2–99) and WOMAC score was 12.3 (range: 0–49) at the final follow up. Multivariate analysis revealed that the poor capsular quality (OR=8.29) was associated with the poor result. The thicker capsule (OR=0.83) and bigger femoral head (OR=0.73) were associated with the good result. There were 15 patients (25.4%) identified as Tonnis grade 0, 21 patients (35.6%) as grade 1, 18 patients (30.5%) as grade 2 and 5 patients (8.5%) as grade 3. According to Severin classification, 28 patients (47.6%) were regarded as class I, 22 patients (37.3%) as II, 7 patients (11.9%) as III and 2 patients (3.4%) as IV. One patient underwent THA after 41.5 months. The joint stiffness was the most common complication (10.2%). We confirmed the efficacy of the capsular arthroplasty in the treatment of young patients with unilateral hip dislocation. The capsular quality and the size of femoral head were associated with the clinical results

Background. Dislocation is a common complication following total hip arthroplasty (THA), and accounts for a high percentage of subsequent revisions. The purpose of this study was to develop a convolutional neural network (CNN) model to identify patients at high risk for dislocation based on postoperative anteroposterior (AP) pelvis radiographs. Methods. We retrospectively evaluated radiographs for a cohort of 13,970 primary THAs with 374 dislocations over 5 years of follow-up. Overall, 1,490 radiographs from dislocated and 91,094 from non-dislocated THAs were included in the analysis. A CNN object detection model (YOLO-V3) was trained to crop the images by centering on the femoral head. A ResNet18 classifier was trained to predict subsequent hip dislocation from the cropped imaging. The ResNet18 classifier was initialized with ImageNet weights and trained using FastAI (V1.0) running on PyTorch. The training was run for 15 epochs using ten-fold cross validation, data oversampling and augmentation. Results. The hip dislocation prediction classifier achieved the following mean performance: accuracy= 49.5(±4.1)%, sensitivity= 89.0(±2.2)%, specificity= 48.8(±4.2)%, positive predictive value= 3.3(±0.3)%, negative predictive value= 99.5(±0.1)%, and area under the receiver operating characteristic curve= 76.7(±3.6)%. Saliency maps demonstrated that the model placed the greatest emphasis on the femoral head and acetabular component. Conclusions. Existing prediction methods fail to identify patients at high risk of dislocation following THA. Our prediction model has high sensitivity and negative predictive value. Therefore, it can be helpful in rapid assessment of risk for dislocation following THA. The model further suggests radiographic locations which may be important in understanding the etiology of prosthesis dislocation

We investigated the preliminary results of femoral head necrosis treated by modified femoral neck osteotomy through surgical hip dislocation in young adults. 33 patients with femoral head osteonecrosis received modified femoral neck osteotomy through surgical hip dislocation from March 2015. 14 patients who had minimal 12 months of follow-up were reviewed radiographically and clinically (mean follow-up:16 months, 12–36 months). The mean age of the patients 32 years at the time of surgery (ranged from 16 to 42years). There were 6 women and 8 men. The cause of the osteonecrosis was steroid administration in 6, alcohol abuse in 4, trauma in 3, and no apparent risk factor in 1. According to the Ficat staging system, 1 hips was stage II, 9 hips III, and 4 hips stage IV. The posterior or anterior rotational angle was 90–180° with a mean of 143°. Clinical evaluation was performed in terms of pain, walk and range of motion on the basis of Merle d'Aubigné hip scores: 17–18 points are excellent, 15–16 are good, 13–14 are fair, 12 or less are poor. Recollapse of the final follow-up anteroposterior radiograph was prevented in 13 hips. One patient got 1 mm recollapse 18 months after surgery. No patient got progressive joint space narrowing. The Merle d'Aubigné score was excellent in 7 hips, good in 5, fair in 2. The preliminary results suggest that modified femoral neck osteotomy through surgical hip dislocation is in favor of young patients. But longer term follow-up is necessary

Purpose. This study re-examined the influence of the head shaft angle (HSA) on hip dislocation in a large cohort of children with cerebral palsy (CP). Method. The radiographs of GMFCS Level III – V children from a surveillance programme database were analysed and migration percentage (MP) and HSA measured. The first radiograph of each patient was taken to remove the effect of the surveillance programme. The most displaced hip in each child, by MP, was used for analysis and the corresponding HSA measured. Hip displacement was defined as MP > 40% and logistic regression was used to adjust for HSA, GMFCS, age and sex. Results. 640 children were eligible (271 female (42.3% ), 369 male (57.7% ), mean age 8.2 years, GMFCS III: 160 (25% ), GMFCS IV: 184 (28.75% ), GMFCS V: 296 (46.25% ). 118 children (18.44% ) had a MP > 40% and mean HSA was 160° (range 111 – 180°). Statistical analysis showed that an increasing HSA was associated with hip displacement (odds ratio of 1.02 for a 1° change). A 10° difference in HSA between two patients of the same age, sex and GMFCS gave odds of 1.26 of the patient with the higher HSA having hip displacement. Age and sex had no influence in this model, while a high GMFCS-level was a strong risk factor. Conclusion. Chougule et al found no correlation between HSA and hip migration in children with CP using linear regression analysis. However, the relationship between these variables is not linear. The present study independently confirms an earlier study that HSA is a risk factor for hip displacement in GMFCS III-V children

Hip displacement is the second most common deformity in children with cerebral palsy (CP). A displaced, and particularly a dislocated hip, can have significantly adverse effects on an individual. Surgical intervention to correct progressive hip displacement or dislocation is recommended for children with CP. Success of surgical intervention is often described using radiological outcomes. There is evidence that surgical treatment for displaced or dislocated hips decreases pain and hip stiffness and improves radiological outcomes. However, there is no information in the literature regarding the impact of surgical treatment on the health related quality of life (HRQOL) in these children. The aim of our study was to examine the impact of surgical treatment of hip displacement or dislocation on HRQOL in children with CP. This prospective longitudinal cohort study involved children attending a tertiary care hospital orthopaedic department. Children with CP between the ages of 4 and 18 years, with hip displacement/dislocation, defined as a Reimer's migration percentage (MP) of >40% on a pre-operative x-ray, and undergoing surgical reconstruction were eligible for inclusion. Quality of life was measured pre-operatively and post-operatively using the CPCHILD Questionnaire. Twelve patients (one child was GMFCS level III, 4 were level IV, and 7 were level V), aged 4.0 to 17.3 years, were assessed pre-operatively and then again at least six months post-operatively. All underwent unilateral (5) or bilateral (7) reconstructive hip surgery. The migration percentage of hips undergoing reconstruction was reduced by an average of 52% (9–100%). The average change in CPCHILD score showed an increase of 6.4 points [95% CI: −1.4–14.2]. In this pilot study, no significant change was noted in HRQOL following reconstructive hip surgery, despite a marked reduction in Reimer's MP. However, only 4 of 12 parents reported that their child had daily pain pre-operatively. A larger sample size will be required to draw more accurate conclusions from these findings. There is an evident need for a multicentre study examining this issue in a larger patient population in order to determine the long-term impact of different hip interventions on quality of life in children with CP

Introduction & Objective. Labral refixation has established as a standard in open or arthroscopic treatment for femoroacetabular impingement (FAI). The rationale for this refixation is to maintain the important suction seal in the hip. To date, only few short-term results are available which indicate a superior result in FAI hips with labral refixation compared to labral resection. Scientific evidence of a beneficial effect of labral refixation in the long-term follow-up is lacking. Aim of this study was to evaluate if labral refixation can improve the cumulative 10-year survivorship in hips undergoing surgical hip dislocation for FAI compared to labral resection. Methods. We performed a retrospective comparative study of 59 patients treated with surgical hip dislocation for symptomatic FAI between December 1998 and January 2003. We analyzed two matched groups: The ‘resection’ group consisted of 25 hips that were treated consistently by excision of the damaged labrum. The ‘refixation’ group consisted of 34 hips that were treated with labral reattachment. Correction of the osseous deformity (rim trimming/femoral osteochondroplasty) did not differ between the two groups. We then evaluated the clinical (Merle d'Aubigné score) and radiographical results (according to Tönnis) at a follow-up of ten years. We calculated a cumulative Kaplan-Meier survivorship curve with the following factors as endpoints: conversion to total hip arthroplasty (THA), radiographic evidence of osteoarthritis progression, or a poor clinical result (defined as Merle d'Aubigné score of less than 15). The two curves were compared using the Log-rank test. Results. Hips with labral refixation had a significantly higher survivorship (78%, 95% confidence interval [CI] 64–92%) at ten years compared to labral resection (46%, 95% CI 26–66, p=0.008). 7 (20.6%) patients in the refixation group reached an endpoint: 2 with THA; 5 with a poor clinical result, and 5 with progression of OA. 15 (60.0%) patients in the resection group reached an endpoint: 3 with THA; 12 with a poor clinical result, and 4 with progression of OA. Conclusion. This is the first study proving that labral refixation leads to significantly better results in patients 10 years after open surgical hip dislocation for FAI. It seems advisable to preserve the labrum in this patient population whenever possible

Aim: This study was performed to review the early results of the use of a semi-constrained acetabular component in the treatment of recurrent hip dislocation at Palmerston North Hospital. Method: A retrospective case study of patients who underwent acetabular component revision with a semi-constrained cup for recurrent dislocation of the hip was performed. Results: Between April 1999 and July 2000, 10 patients with an average age of 75 years underwent acetabulum revision with a semi-constrained cup. There was an average of four dislocations before revision surgery, per patient. At follow-up between three and 18 months after the revision, there had been no dislocations. Aggressive post-operative rehabilitation was permitted, allowing discharge at an average of seven days postoperatively. Conclusion: The use of a semi-constrained acetabular cup was successful as a means of treatment for recurrent hip dislocation. This is an early review of the use of the implant. There are no published data on long term survival of this implant. The semi-constrained cup provides a simple yet effective option for dealing with the elderly recurrent hip dislocation

Aim. To assess the risk of hip dislocations in children with cerebral palsy (CP) attending special schools, and the effects of preventative soft tissue surgery (psoas and adductor tenotomy). Method. 110 children were reviewed from 1985-2000. Severity of CP was graded according to the Gross Motor Function Classification System (GMFCS). Hemiplegics - grade 1, Diplegics grades 2 & 3, Quadriplegics grades 4 & 5. Patients were grouped into age groups 5, 10 and 15 years and the number of hip dislocations in each group were noted. Numbers of patients who had preventative soft tissue surgery was also noted. Indication for surgery, >35% femoral head uncovering. Results. Percentage of dislocations increased with CP severity. At 15 years, no dislocations in GMFCS 2, 6% GMFCS 3, 19% GMFCS 4 and 40% in GMFCS 5. The number of patients with at least 1 hip dislocation increased with age at all age groups. GMFCS 4 (age 5 yrs 9%, age 10 yrs 20% and 15 yrs 30%). GMFCS 5 (age5 yrs 22%, age 10 yrs 48% and age 15 yrs 50%). By 15 years, 54 hips in GMFCS 2 & 3 (diplegics), preventative soft tissue surgery had not reduced chances of hip dislocation; only 1 dislocated (2%). In GMFCS 4 & 5 (quadriplegics), dislocations reduced from 40% in those without surgery to 26% in those who had preventive soft tissue surgery. This was particularly so in GMFCS 5 where there was a reduction from 83% dislocation without surgery to 33% with soft tissue preventive surgery. Conclusions. Preventive soft tissue surgery was effective in reducing the rate of hip dislocation in quadriplegic CP especially GMFCS 5

Objective: The presentation of mid-term results of porous tantalum TMT cup in congenital high hip dislocation. Materials and Methods: Between November 1997 and December 2000, we performed 27 total hip replacements in 22 women patiens suffering from high congenital hip dislocation according Xartofilakidis classification. The acetabular component was implanted at the true acetabular bed with restoration of the centre of hip rotation. Clinical and radiological observation took place in regular intervals for an average time of 10.2 years (8.5–12 years). Results: The average Harris Hip Score improved from 48.3 preoperatively (range 15–65) to 89.5 at the latest follow-up (56–100). Oxford hip score declined from 49.5 preoperatively to 21.2 at the first year and to 15.2 at five years examination. The absolute acetabular component’s migration was evaluated by EBRA method in the first 2 years and was at average 0.85 mm at the first year and 1.05 mm at the second year. An incident of gross initial migration was observed. No acetabular revision was performed and there was no case of mechanical loosening. Conclusion: The acetabular TMT component is highly adhesive and porous with a modulus of elasticity close to subchondral bone. It promotes initial stability, induces bone penetration and integration and offers a more “physiologig” load transfer. It also offers adequate polyethylene thickness, even in the smallest sizes, due to its manufacturing. The recent results from its use in high hip dislocation are excellent and justify the further study of longevity and probably the superiority of this material

Two cases of assymptomatic hip dislocation discovered incidentally are presented. Case 1- A 63-year old lady had an uncemented primary total hip replacement of the left hip for painful osteoarthritis in July 1993. She made an uneventful recovery post-operatively. This lady had no neurological abnormality and was mobilising independently. In April 2001,8 years later she was admitted as an emergency for suspected diverticulitis of the colon. Plain radiographs performed showed dislocated hip prosthesis. Case 2- This 75-year old lady, an active farmer, had right hip arthroplasty in July 1990 for painful osteoarthritis and made an uneventful recovery subsequently. She also did not have any neurological abnormality and was mobilising independently too. Dislocated prosthesis was discovered radiologically in December 2001 during a pre-operative work-up for the left hip (the other hip) arthroplasty. Discussion: Late dislocation is more common than was thought previously. Several separate processes, some distinct from those associated with early dislocation, can lead to late dislocation. It can occur in association with a long-standing problem with the prosthesis that manifests late (such as malposition of the implant or recurrent subluxation), it can occur in association with a new problem (such as neurological abnormality, trauma or polyethylene wear), or it can occur in association with combination of these factors. Both these patients were mobilising independently and did not suffer from any neurological abnormality. Both these patients had asked to be discharged after an initial 2-year follow-up. They had not experienced any problem with the hip replacement. These dislocated prosthesis were discovered incidentally. Revision arthroplasty was carried out successfully in both these patients. These cases emphasise the need for long-term clinical and radiological follow-up in hip arthroplasty patients as hip dislocations can be assymptomatic and not detected by clinical examination. Radiological review alongside evaluation using scoring systems is recommended

Introduction. Magnetic resonance imaging with intraarticular contrast (arthro-MRI) and radial cuts is the gold standard to quantify labral and chondral lesions in the setting of femoroacetabular impingement. To date, no study exists that has evaluated these findings as potential predictors of outcome for the long term follow-up after surgical treatment of FAI. Objectives. The purpose of this study was to detect potential predictors for failure after surgical hip dislocation for FAI based on specific preoperative arthro-MRI of the hip at a minimum follow-up of 10 years. Methods. Retrospective case series of 97 hips (75 patients) undergoing surgical hip dislocation for FAI between July 2001 and March 2003. Minimum follow-up was 10 years. Twelve radiographic factors were preoperatively evaluated on specific arthro-MRIs with radial cuts of the hips. Patients were then evaluated clinically and radiographically at latest follow-up (mean followup of 11 years, range 10–13 years). The following endpoints were chosen: conversion to total hip arthroplasty (THA), radiographic evidence of progression of osteoarthritis (OA), and/or a Merle d'Aubigné-Postel score of less than 15 indicating a poor clinical result. Univariate and multivariate Cox-regression analysis were performed with these endpoints as failures. Results. Hips with failure at 10-year follow up after surgical hip dislocation where more likely to show typical signs like decentration of the femoral head (52.9% compared to 17% in hips with good long term outcome; p = 0.007) in preoperative arthro-MRI evaluation. The strongest arthro-MRI based predictors of failure at the 10 year follow-up were a ‘double fond’ (hazard ratio with 95% confidence interval, 3.4 [3.2–3.7], p = 0.001), decentration of the femoral head (3.0 [2.8–3.3], p = 0.004) and posterior-inferior femoral osteophytes (3.3 [3.1–3.6], p = 0.002). Conclusions. Factors like double fond, decentration of the femoral head and postero-inferior femoral osteophytes in preoperative arthro-MRI predict inferior long term outcome after surgical hip dislocation for FAI. Therefore we recommend preoperative evaluation with arthro-MRI in addition to conventional radiography