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

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

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

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

Little is published about the use of cementless conical stems in primary hip arthroplasty for congenital hip disease. A conical stem was designed in the 80’s by Prof. Wagner. The stem is made of a rough blasted titanium alloy with a cone angle of 5° and 8 sharp longitudinal “ribs” that cut into the inner cortex, designed to achieve rotational stability: The ribs depth of penetration ranges between 0.1 and 0.5 mm and is also very important to achieve osteo-integration. The CCD angle is 135°. The stem is straight and can be implanted in any degree of version thus being very useful for dysplastic arthritis with significant femoral neck anteversion. Between 1993 and 1998 the senior author (RB) implanted 92 conical stems in 88 consecutive patients with dysplastic arthritis. The acetabular component was cementless and titanium with tridimensional porosity. The articulating surface was a second generation Metal-on-Metal.with a femoral head of 28 mm. According to the Hartofilakidis classification 63 patients had type A, 18 type B and 11 type C. The average follow-up was 11.2 years (range 10.1–14.8). Using the Harris Hip Scoring system we had 82 (89%) satisfactory results, with excellent correction of pre-op pain (42/44 Harris) and no case of anterior thigh pain; 88% of patients had no or slight limp at follow-up. No patient required revision of the stem, but one cup required revision for loosening (Type C class). We had one dislocation (1%) that was treated conservatively. Radiographically, all stems were osteo-integrated, 17% showed some resorption in femoral zone 1 and 7. In the same zones we observed 4 cases of real osteolysis without loosening. No radiolucent line was observed in other femoral zones. In the acetabular side we had 13 cases (14%) of radiolucency, but in only 1 case (1%) was it progressive. A straight conical titanium femoral stem gave very satisfactory clinico-radiographical results in dysplastic arthritis at a mean of 11.2 years of follow-up

For better communication, treatment planning and evaluation of results, a generally accepted classification is needed for determining the different types of congenital hip disease (usually referred to as developmental dysplasia of the hip) in adults. We have proposed the use of the following classification: Dysplasia, Low Dislocation, and High Dislocation. Knowledge of the local anatomical abnormalities in these three types of the disease is mandatory. Total hip arthroplasty in all three types (especially in high dislocation) is a demanding operation and should be decided when there is an absolute indication. The acetabular component must be placed at the site of the true acetabulum, mainly for mechanical reasons. After the reaming process, if the remaining osseous cavity cannot accommodate a small cementless cup with at least 80% coverage of the implant, the cotyloplasty technique is recommended. This technique involves medial advancement of the acetabular floor by the creation of a controlled comminuted fracture, autogenous bone grafting, and the implantation of a small acetabular component with cement, usually the offset-bore acetabular cup of Charnley. In order to facilitate reduction of the components and to avoid neurovascular complications, the femur is shortened at the level of the femoral neck, along with release of the psoas tendon and the small external rotators. We believe that this operative technique of total hip arthroplasty is effective for the treatment of difficult conditions of highly dislocated hips

The purpose of this study was to analyse the complications of THAs in CDH. 418 THAs were performed in 356 patients, with a mean follow-up 108 (7–237) months. The mean age was 53.3 (24–79) years. 83 patients had CDH in high position. 40 stems were custom made. Complications included seven intraoperative fractures of the femur, 12 dislocations, four peroneal nerve palsies that recovered, 25 heterotopic ossifications, seven deep vein thromboses, three pulmonary embolisms, early mechanical loosening in four cemented and ten cementless cups and three infections. Complications were diminished dramatically last years due to improved surgical technique, new available implants and preoperative evaluation of the hip with CT and CAD-CAM-CAE study.

Total hip arthroplasty (THA) in neglected congenital dislocation of the hip (CDH) constitutes a challenging procedure, with surgical difficulties and complications. The purpose of this study was to analyse the complications of THAs in CDH.

Between June 1983 and September 2002, 418 THAs-were performed in 356 patients with CDH, with a mean follow-up 108 (7–237)months. The mean age at surgery was 53.3 (24–79) years with 325 females and31 males. 83 patients had CDH in high position. 307 arthroplasties were cementless, 39 cemented and 72 hybrids. 40 stems were custom made. The cup always was positioned at the true acetabulum. 24 shortening osteotomies of the femur, 8 corrective supracondylar and 6 trochanteric osteotomies were performed.

Preoperatively the average Merle d’Aubigne-Postel hip score was 1.1 for pain, 4.8 for range of motion and 3.1 for walking ability. Postoperatively the average hip score was 5.2, 4.7 and 5.3 respectively. The average length discrepancy was 8 cm (3–12) preoperatively and 1.5 cm remained in 8 patients. Complications included 7 intraoperative fractures of the femur, 12 dislocations, 4 peroneal nerve palsies that recovered, 25heterotopic ossifications, 7 deep vein thromboses, 3 pulmonary embolisms, early mechanical loosening in 4 cemented and 10 cementless cups and 3infections.

Complications were diminished dramatically last years due to improved surgical technique, new available implants and preoperative evaluation of the hip with CT and CAD-CAM-CAE study that allowed better surgical planning with trial stem implantation from a series of stem designs and custom made femoral components manufacturing

Our study evaluated the reliability of the Crowe and Hartofilakidis classification systems for developmental dysplasia of the hip in adults. The anteroposterior radiographs of the pelvis of 145 patients with 209 osteoarthritic hips were examined twice by three experienced hip surgeons from three European countries and the abnormal hips were rated using both classifications. The inter- and intra-observer agreement was calculated.

Interobserver reliability was evaluated using weighted and unweighted kappa coefficients and for the Crowe classification, among the three pairs there was a minimum kappa coefficient with linear weighting of 0.90 for observers A and C and a maximum kappa coefficient of 0.92 for observers B and C. For the Hartofilakidis classification, the minimum kappa value was 0.85 for observers A and B, and the maximum value was 0.93 for observers B and C. With regard to intra-observer reliability, the kappa coefficients with linear weighting between the two evaluations of the same observer ranged between 0.86 and 0.95 for the Crowe classification and between 0.80 and 0.93 for the Hartofilakidis classification.

The reliability of both systems was substantial to almost perfect both for serial measurements by individual readers and between different readers, although the information offered was dissimilar.

We report the results at a mean of 24.3 years (20 to 32) of 61 previously reported consecutive total hip replacements carried out on 44 patients with severe congenital hip disease, performed with reconstruction of the acetabulum with an impaction grafting technique known as cotyloplasty. The mean age of the patients at operation was 46.7 years (23 to 68) and all were women. The patients were followed post-operatively for a mean of 24.3 years (20 to 32), using the Merle d’Aubigné and Postel scoring system as modified by Charnley, and with serial radiographs. At the time of the latest follow-up, 28 acetabular components had been revised because of aseptic loosening at a mean of 15.9 years (6 to 26), and one at 40 days after surgery because of repeated dislocations. The overall survival rate for aseptic failure of the acetabular component at ten years was 93.1% (95% confidence interval (CI) 86.5 to 96.7) when 53 hips were at risk, and at 23 years was 56.1% (95% CI 49.4 to 62.8), when 22 hips remained at risk. These long-term results are considered satisfactory for the reconstruction of an acetabulum presenting with inadequate bone stock and circumferential segmental defects. Cite this article: Bone Joint J 2013;95-B:887–92

Local anatomical abnormalities vary in congenital hip disease patients. Authors often present early to mid-term total hip arthroplasty clinical outcomes using different techniques and implants randomly on patients with different types of the disease, making same conclusions difficult. We report long term outcomes (13 to 23 years) of the treatment of low and high dislocation cases (separately) with total hip arthroplasty using TM technology acetabular cups (Implex initially and then Zimmer) and short fluted conical (Zimmer) femoral stems. From 2000 to 2010, 418 congenital hip disease hip joints were treated in our department with total hip arthroplasty. According to Hartofilakidis et al's classification, 230 hips had dysplasia, 101 low dislocation, (group A) and 87 high dislocation (group B). Pre-operative and post-operative values, at regular intervals, of HHS, SF-12, WOMAC, OHS and HOOS were available for all patients. Patient, surgeon and implant related failures and complications were recorded for all patients. In all cases an attempt was made to restore hip center of rotation. In group A the average lengthening was 2.8 cm (range: 1 to 4.2) and in group B 5.7 cm (range: 4.2 to 11). In both groups, no hips were revised due to aseptic loosening of either the acetabular cup or the femoral stem. In group A, a cumulative success rate of 95.6% (95% confidence interval, 92.7% – 97.4%) and in group B a cumulative success rate of 94.8% (95% confidence interval, 92.6%–96.9%) was recorded, at 20 years, with revision for any reason as an end point. No s.s. differences were found between groups when mean values of HHS, SF-12, WOMAC and OKS were compared. Satisfactory long-term clinical outcomes can be achieved in treating different types of congenital hip disease when appropriate surgical techniques combined with “game changing” implants are used

Introduction: Operative treatment of secondary osteoarthritis due to congenital hip disease (CHD) in adults presents a challenging issue. Various classifications have been proposed for congenital hip disease in search for the best treatment option. Aim of this prospective study is to find measurements important in preoperative planning and their correlation with postoperative results. Materials and Methods: We have included 64 patients (70 hips) with CHD consecutively scheduled for operation. Preoperatively congenital hip disease was classified according to Crowe, Hartofilakidis and Eftekhar and center of rotation was determined using Ranawat’s method. Distance between ideal and actual center rotation was measured. Further, distance between medial acetabular wall and medial pelvic rim (medial bone bulk) in the line of ideal center of rotation was measured. Another measurement was distance between ideal acetabular roof point and medial pelvic rim. On the postoperative radiographs centre of the femoral head was recorded. Correlation between Crowe, Hartofilakidis and Eftekhar classifications with distance between ideal and postoperative center rotation and medial bone bulk were calculated using Pearson correlation. Correlation was also analyzed using information about distance between ideal acetabular roof point and medial pelvic rim. Results: Data analysis showed that there is the strongest connection between degree of CHD determined using Eftaker classification and distance between ideal and actual rotation center (r=0.417, p=0.011). Crowe and Hartofilakidis classifications also shows statistically significant connection, however not that strong (r= 0.384, p=0.021 for Crowe and r=0.373, p=0.025 for Hartofilakidis). Eftaker classification shows the strongest correlation with medial bone bulk r=0.425, a p=0.010. Similar is Crowe classification (r=0.341, p=0.042), while there is no statistically significant correlation with Hartofilakidis classification. Results also shows that when there is higher degree of congenital hip disease there is thinner bone bulk in line of ideal acetabular roof (for Crowe r= −0.360, p=0.031, for Hartofilakidis r= −0.354, p=0.34). Conclusion: Results show that severity of dysplasia according to Crowe, Hartofilakidis and Eftekhar correlates with postoperative position of rotation center. Eftekhar classification gives the best insight to how much medial bone bulk is available. For bone bulk on the acetabular roof predictions can be made using both Crowe and Hartofilakidis system. However, one classification still does not provide with all information we found important for correct endoprothesis placement in relation to center of rotation especially about acetabular depth, and bone mass on the medial acetabular wall and acetabular roof

We reported on the outcome of 84 Charnley low friction arthroplasties performed by one of us (GH), the period 1973 to 1984, in 69 patients, less than fifty-five years old, with osteoarthritis mainly due to congenital hip disease. The patients were followed prospectively; clinically using the Merle D’Aubigné and Postel scoring system, as modified by Charnley and also radiographically. At the time of the latest follow-up, thirty-seven hips had failed (44%). In thirty-two hips, twenty-eight acetabular and thirty femoral components were revised because of aseptic loosening (six of the femoral components were broken). Three hips were infected and converted to resection arthroplasty. In two more hips a periprosthetic femur fracture occurred three and ten years postoperatively and were treated with internal fixation. After a minimum of twenty-two years from the index operation, 37 original acetabular components and 36 original femoral components were in place for an average of 29 years. The probability of survival for both components with failure for any reason as the end point was 0.51 (95% confidence interval, 0.39 to 0.62) at twenty-five years when 35 hips were at risk. These long term results can be used as a benchmark of endurance of current total hip arthroplasties performed in young patients, with OA mainly due to congenital hip disease

AIM OF STUDY: The mid and long-term clinical and radiological evaluation of patients with degenerative arthritis secondary to congenital hip diseases with placement of the cup proximal to the true acetabulum. MATERIAL AND METHODS: We operated on a total of 99 hips (90 patients) with arthritis due to CHD from 1996 to 2006. In 48 of these hips (mean age 55.8 yrs), the cup was inserted high. The procedure was always performed with the patient in lateral position through a lateral transgluteal approach. We did not perform osteotomies of the greater trochanter or femur shortening osteotomies and the cup was placed where there was sufficient bone stock. The major determining factor in cup stability was the presence of sufficient anterior and posterior column. We also tried to insert the cup as medial as possible although in about half the group (25 out of 48), cup placement was superior and lateral. The limb length discrepancy was corrected by varying the neck length of the implant. A special stem was used in 5 cases. The mean intraoperative time was 65 mins with minimal soft tissue disruption as compared with the classic methods. The patients were mobilized postoperatively in a couple of days. RESULTS: Despite the higher rates described in literature, cup loosening occurred in only two hips and there was no incidence of stem loosening. There were no neurological complications. There were three complications in total: one DVT and two dislocations due to cup loosening as a result of mal-positioning. CONCLUSIONS: The extremely low rate of cup loosening, improvement of Harris Hip Score and back pain, decreased intraoperative time are significant advantages of managing congenital hip diseases with the above technique using the uncemented Zweymüller implants. The long period of follow up (8 to 11 years for 31% of the patients) in this study is significant

The aim of this study was to evaluate the results of total hip arthropiasty in osteoarthritis secondary to congenital hip disease. During the period 1986 to 1999, we performed 48 hip replacements with congenital hip disease. According to classification of Chanophylakidis there were 18 dysplastic hips without dislocation, 17 hips with low dislocation and 12 hips with high dislocation The mean age of the patients was 49 years (range from 31 to 64) Depended on the pathology of each case, different types of prostheses or combinations of them were used. The acetabular cup was placed in the anatomic position and in the majority of cases a component of 22 aim was used. In 28 cases the bottom of the acetabulum was fractured and protruded in order to fit the cup (acetabuloplasty). In these cases copious amounts of auto- and aiiografts were used and the cup was fixed with PMMA, Special femoral stems for CDH were used and in the majority of cases they were fixed with PMMA. In 17 cases with good acetabular bone stock and good femoral canal a standard prosthesis was used without PMMA. In 31 cases the hip was approached after osteotomy of the grater trochader and in 17 cases an anterolateral approach was used. Intra-operatively there were many problems and difficulties but we had no true complications. Early postoperative complications presented in eight patients and had to do with 2 haematomas, 3 DVT, 1 mild PE and 2 superficial infections. There was no case of deep infection, neurovascular damage, dislocation or fracture. The late results after a mean of 6, £ years were very satisfaaory. There was improvement of the HIP SCORE from 38 to 83 and subjective satisfaction of nearly all the patients. The late complications were limited and they concerned three migrations of the acetabular cup, one aseptic loosening of the femora) stem and one extensive osteoiysis the proximal femur. All the above cases were revised successfully

Introduction. The use of screws is frequent for additional fixation, however, since some disadvantages have been reported a cup press-fit is desirable, although this can not always be obtained. Cup primary intraoperative fixation in uncemented total hip replacement (THR) depends on sex, acetabular shape, and surgical technique. We analyzed different factors related to primary bone fixation of five different designs in patients only diagnosed with osteoarthritis, excluding severe congenital hip disease and inflammatory arthritis, and their clinical and radiological outcome. Materials y Methods. 791 hips operated in our Institution between 2002 and 2012 were included for the analysis. All cases were operated with the same press-fit technique, and screws were used according to the pull-out test. Two screws were used if there was any movement after the mentioned manoeuvres. Acetabular and femoral radiological shapes were classified according to Dorr et al. We analyzed radiological postoperative cup position for acetabular abduction angle, the horizontal distance and the vertical distance. Cup anteversion was evaluated according to Widmer and the hip rotation centre according to Ranawat. Results. Screws were required in 155 hips (19.6%) and were more frequently used in women and patients with a type A acetabulum (p<0.001, p=0.021, respectively). There were no differences among the different cups evaluated. The need for screws was more frequent in hips with a smaller version of the cup and with a distance greater than 2 mm to the approximate femoral head centre from the centre of the prosthetic femoral head (p=0.022, 0.012, respectively). Adjusted multivariate analysis revealed that female patients (p<0.001, Odds Ratio (OR): 2.063; 95% Confidence Interval (CI) 1.409–3.020), cups with a smaller version (p=0.012, OR: 0.966, 95% CI 0.94–0.992), and a greater distance to the rotation hip center (p<0.005, OR: 1.695; 95% CI 1.173–2.450) had a higher risk for screw use. No hips needed revision for aseptic loosening. Conclusions. Cup press-fit depends on gender and surgical technique in hips without significant acetabular abnormalities or inflammatory arthritis. Contemporary uncemented cups provide similar primary fixation and mid-term outcome

The purpose of this study is to present early results, common pitfalls and management in in cases of revision hip arthroplsty in patients with congenital disease of the hip. From 2001 to 2006, 36 consecutive cemented THAs with a history of congenital hip disease were revised due to aseptic loosening (31 cases), stem fracture (3 cases), septic loosening (2 case). There were thirty patients, all females, with a mean age at revision 61.7 years (range, 40 to 76). The revision was performed after a mean 15.4 years post primary operation (range, 9 to 26). In 7 cases the cup only, in 5 cases the stem only, and in 24 cases both components were revised. The mean follow-up was 43 months (range, 24 to 84). There were 3 intraoperative femoral fractures managed with long stem and circlage wires. Postoperatively, 5 hips were infected and sustained a 2 stage revision using a cement spacer. 3 hips were revised due to loosening. 28 cups and 28 stems remained intact for an average 45.2 months (range, 24 to 84). The probability of survival at 48 months was 76.3% (±9.7%) for the cups (12 components at risk) and 76.4% (±11.3%) for the stems (9 components at risk). Revision of a CDH arthroplasty is difficult and non predictable. Lack of acetabular bone stock and anatomical abnormalities of the femur lead to increased intra and postoperative complication rate

Purpose: The prognosis of congenital hip displacement basically depends on the time of diagnosis and treatment. Recognising high-risk hips early remains a number one priority. We conducted a prospective study over a 20-year period from 1992 to 2002 to analyse the epidemiology of congenital hip displacement. Material and methods: The series included 1056 children with congenital hip disease (1491 hips). Epidemiological data, ultrasound and x-ray findings were recorded over 20 years. The objective was to identify risk factors and evaluate the impact of prevention measures. Results: The sex ratio showed female predominance, 6:1. The left hip was involved 1.8 times more often, with 41% bilateral involvement. Risk factors were major: family history (31%), breech presentation (25%), postural syndrome (12%); or minor: primiparity (54.4%), birth weight > 4 kg (9.2%). One or more major risk factors were found in 60.5% of the children and 30% had at least one minor risk factor. No risk factor was found in 40%. Screening efficacy improved with a rate of diagnosis before 4 months of 59% in 1983 and 96% in 2002. The number of hips discovered after the age of one year was 15% in 1983 and 6% in 2002. Discussion: The severity of the hip displacement is not influenced by risk factors nor bilateral involvement. Screening has enabled earlier diagnosis with a 37% increase in the rate of identification before the age of four months. This has been made possible by a systematic examination at birth and ultrasonography introduced in 1989. Conclusion: A regional map showing the paediatrician : maternity : general practitioner distributions is an important tool for screening campaigns. Despite adequate screening 40% of these children do not have any risk factor. Repeated examinations, communication and information exchange between healthcare professionals are the keys to success

The adult congenital hip dislocations and dysplasias have been previously classified by Eftekhar, Crowe et al., Hartofilakidis et al., Kerboul et al. and Mendes et al. The most conventient and widely used one is the Hartofilakidis and Crowe classification. Three different types of congenital hip disease in adults have been distinguished by Hartofilakidis and et al. based upon the position of the femoral head relative to the acetabulum: dysplasia; low dislocation; and high dislocation. All these classification systems are only radiological and does not highlight the operative technique in detail and the complications that we can observe perioperatively. Our classification system is also a radiological classification system but more useful for predicting the difficulty of the operative procedure and selecting the right operative method. In our classification system; at type I; dysplasia and less than 25% subluxations, we divided type I in to three subgroups, at type Ia, only dysplastic acetabulums, at type Ib, with elephant’s trunk type osteophyte formation and at type Ic, curtain type osteophytic formations, we included dysplasia and less than 25% subluxations in the same group because of operative technique similarities. At type 2; subluxations between 25% and 75%, we divided type II in two subgroups according to the angle between the inner margin of the teardrop and superior border of the acetabulum, at type IIa, the angle is less than 60°, at type IIb, the angle is greater than 60°, it’s important to show femoral allogreft usage requirement, at type 3; subluxations greater than 75%, at this type there will be no need of femoral allogreft usage but extra-small reamer usage for forming a suitable acetabular bed. At type 4; luxations greater than 100%, we also divided type IV in to two subgroups accordind to the distance between superior margin of true acetabulum and trochanter major line, at type IVa, < 2.5 cm, at type IVb, > 2.5 cm. It’s also important to make the decission of shortening. To form this classification three observers with different levels of training independently classified 412 dysplastic hips (operated between1995 and 2005) on 380 standard anteriorposterior pelvis radiographs, retrospectively according to the criteria defined by us. To assess intraobserver reliability, the measurement was repeated 3 months later. Statistical analysis was performed by calculating the weighted kappa correlation coefficient. System showed good inter- and intraob-server reliability for use in daily practice. Eventually, we determined a significant correlation between the aplied surgical procedures and classification. As a conclusion, we believe that our classification system of osteoarthritis secondary to developmental dysplasia of the hip in adult patients guides the surgical procedure more effectively than the other classification systems

Aims

We present the clinical and radiological results at a minimum follow-up of 20 years using a second-generation uncemented total hip arthroplasty (THA). These results are compared to our previously published results using a first-generation hip arthroplasty followed for 20 years.