Acetabular reconstruction in patients with low and high dislocation: 20- to 32-year survival of an impaction grafting technique (named cotyloplasty)

Long-term outcomes of total hip arthroplasty in patients with developmental dysplasia of the hip: a minimum 21-year follow-up

PURPOSE

Early osteoarthritis (OA) due to developmental dysplasia of the hip (DDH) is a known indication for total hip arthroplasty (THA). Though screening tools and joint-preserving procedures have been established successfully, there still is a relevant number of patients suffering DDH. Due to the lack of long-term outcome studies, we like to close this gap and present the results of a highly specialized center.

METHODS

The study included 126 patients, who were treated in our institution with primary THA for DDH between January 1997 and December 2000. At the time of final follow-up, at a mean of 23 years postoperatively, 110 patients (121 hips) were clinically evaluated using the Harris-Hip Score. In addition, complication and surgical revision rates were assessed. We collected surgery-related data like implant choice and special surgical features such as autologous acetabular reconstruction or femoral osteotomies. Additionally, the severity of preoperative DDH was measured radiographically according to Crowe classification.

RESULTS

There were 91 female (83%) and 19 male (17%) patients with an average age of 51 ± 9.5 years (range 21-65) included. Mean follow-up was 23 ± 1.3 years (21-25), with a minimum of 21 years being necessary for inclusion. Using revision for any indication as primary endpoint, the Kaplan-Meier survivorship was 98.3% at 10 years and 81.8% at final follow-up. The overall revision rate was 18% (22 cases), which were split up as follows: 20 (17%) implant failures (loosened or broken components), one (1%) periprosthetic infection and one (1%) periprosthetic fracture. Regarding complications, we observed nine (7%) dislocations and one case (1%) with severe heterotopic ossification that required surgical excision. The mean Harris-Hip score at latest follow-up was 78 ± 14 points (32-95).

CONCLUSIONS

Though implants and surgical techniques have improved over time, our results suggest THA in patients suffering DDH to be seriously challenging with relatively high overall complications in long-term observation and fair clinical outcome after 21 years postoperatively. There is evidence that prior osteotomy might be associated with a higher revision rate.

Total Hip Arthroplasty in Patients with Crowe III/IV Developmental Dysplasia of the Hip: Acetabular Morphology and Reconstruction Techniques

The severe anatomic deformities render acetabular reconstruction as one of the greatest challenges in total hip arthroplasty (THA) for patients with Crowe III/IV developmental dysplasia of the hip (DDH). Thorough understanding of acetabular morphology and bone defect is the basis of acetabular reconstruction techniques. Researchers have proposed either true acetabulum position reconstruction or high hip center (HHC) position reconstruction. The former can obtain the optimal hip biomechanics, including bulk femoral head autograft, acetabular medial wall displacement osteotomy, and acetabular component medialization, while the latter is relatively easy for hip reduction, as it can avoid neurovascular lesions and obtain more bone coverage; however, it cannot achieve good hip biomechanics. Both techniques have their own advantages and disadvantages. Although there is no consensus on which approach is better, most researchers suggest the true acetabulum position reconstruction. Based on the various acetabular deformities in DDH patients, evaluation of acetabular morphology, bone defect, and bone stock using the 3D image and acetabular component simulation techniques, as well as the soft tissue tension around the hip joint, individualized acetabular reconstruction plans can be formulated and appropriate techniques can be selected to acquire desired clinical outcomes.

Femoral head and neck autograft in arthroplasty for developmental dysplasia of the hip: a systematic review of long-term outcomes

PURPOSE

Total hip arthroplasty (THA) with an acetabular component and an autogenous femoral head graft for acetabular reconstruction in developmental dysplasia of the hip was first described by Harris et al. in 1977. While a number of studies have addressed the aforementioned scenario over the last decades, most lack sufficient numbers and follow-up. As such, we analyzed long-term outcomes of THAs with femoral autograft for arthrosis secondary to hip dysplasia.

METHODS

A systematic review was performed using a structured PubMed, Web of Science, Ovid MEDLINE, and Cochrane analysis, based on the PRISMA criteria. All original studies from 1977 to 2022 with a mean follow-up of 10 or more years were included. Methodological Index for Nonrandomized Studies (MINORS) were used for quality assessment.

RESULTS

A total of 26 studies with 1316 patients (87% females) undergoing 1543 THAs with femoral autograft (2 times neck graft, 24 times head graft) were included. Mean age was 52 years (range, 28-73) and the mean follow-up was 13 years (range, 9-18). The revision rate was 8.3% (n = 129), and 73% of revisions were for loosening. Rate of infection (0.5%) and dislocations (1%) were low. Radiographic analysis revealed 167 loose acetabular components (11%) and 118 cases of graft resorption (7.6%). Mean Harris Hip Score increased from 42 to 85. Mean MINORS score was 11, and no study was level of evidence I or II.

CONCLUSIONS

Femoral autograft with THA may be a viable long-term option for hip reconstruction in developmental dysplasia of the hip. However, moderate loosening rates and low level of evidence must be acknowledged before drawing the final conclusions.

LEVEL OF EVIDENCE

Therapeutic Level III.

Minimum 10-Year Results of Cementless Ceramic-On-Ceramic Total Hip Arthroplasty Performed With Transverse Subtrochanteric Osteotomy in Crowe Type IV Hips

BACKGROUND

Total hip arthroplasty (THA) performed for developmental dysplasia of the hip is a technically difficult procedure with a high complication rate, especially in the presence of completely dislocated hips. This study aimed to evaluate at least 10 years of follow-up results of cementless, ceramic-on-ceramic (CoC) THA performed with transverse subtrochanteric osteotomy in Crowe type IV hips.

METHODS

We retrospectively reviewed 50 patients' 67 hips that underwent CoC, cementless THA with transverse subtrochanteric osteotomy between 2008 and 2011. Clinical and radiological data of the hips were examined. Clinical results were evaluated using the Harris Hip Score and the Western Ontario and McMaster Universities Osteoarthritis Index.

RESULTS

The mean Harris Hip Score improved from 22.9 ± 9.9 preoperatively to 94.1 ± 8.1 at the final follow-up (P < 0.001). The median Western Ontario and McMaster Universities Osteoarthritis Index score improved from 72 (interquartile range: 17) preoperatively to 2 (interquartile range: 17) postoperatively (P < 0.001). The preoperative mean leg length discrepancy was improved from 4.9 ± 1 cm to 1.5 ± 1 cm in unilateral cases at the last follow-up (P < 0.001). Revision surgery was required because of nonunion in two patients, prosthetic infection in one patient, and aseptic femoral loosening in the other patient. The overall ten-year survival rate was 94% for femoral stems and 98.5% for acetabular components as per Kaplan-Meier survival analysis.

CONCLUSION

Transverse subtrochanteric shortening osteotomy combined with using cementless acetabular and femoral components with a CoC bearing surface promises successful clinical results and high prosthesis survival in the treatment of Crowe IV hips at long-term follow-up.

Cemented acetabular component with femoral neck autograft for acetabular reconstruction in Crowe type III dislocated hips

AIMS

Various surgical techniques have been described for total hip arthroplasty (THA) in patients with Crowe type III dislocated hips, who have a large acetabular bone defect. The aim of this study was to evaluate the long-term clinical results of patients in whom anatomical reconstruction of the acetabulum was performed using a cemented acetabular component and autologous bone graft from the femoral neck.

METHODS

A total of 22 patients with Crowe type III dislocated hips underwent 28 THAs using bone graft from the femoral neck between 1979 and 2000. A Charnley cemented acetabular component was placed at the level of the true acetabulum after preparation with bone grafting. All patients were female with a mean age at the time of surgery of 54 years (35 to 68). A total of 18 patients (21 THAs) were followed for a mean of 27.2 years (20 to 33) after the operation.

RESULTS

Radiographs immediately after surgery showed a mean vertical distance from the centre of the hip to the teardrop line of 21.5 mm (SD 3.3; 14.5 to 30.7) and a mean cover of the acetabular component by bone graft of 46% (SD 6%; 32% to 60%). All bone grafts united without collapse, and only three acetabular components loosened. The rate of survival of the acetabular component with mechanical loosening or revision as the endpoint was 86.4% at 25 years after surgery.

CONCLUSION

The technique of using autologous bone graft from the femoral neck and placing a cemented acetabular component in the true acetabulum can provide good long-term outcomes in patients with Crowe type III dislocated hips. Cite this article: Bone Joint J 2021;103-B(2):299-304.

Controlled fracture of the medial wall versus structural autograft with bulk femoral head to increase cup coverage by host bone for total hip arthroplasty in osteoarthritis secondary to developmental dysplasia of the hip: a retrospective cohort study

Background

Many methods have been proposed to increase cup coverage by host bone during primary total hip arthroplasty (THA) in hip osteoarthritis secondary to developmental dysplasia of the hip (DDH). However, there was no study comparing the results of controlled fracture of the medial wall with a structural autograft with a bulk femoral head.

Methods

Sixty-seven hips classified as Crowe II/III were retrospectively included in this cohort study, which consisted of 33 controlled fractures (group A) and 34 structural autografts (group B). The Harris Hip Scores (HHS) were recorded. The radiological assessments were analyzed. Also, complications are assessed. The paired-sample t test was used for data analysis before and after the operation, while the independent sample T test was used for the comparison between the two groups. The Pearson chi-square test or the Fisher exact test was used to analyze the qualitative comparative parameters. Kaplan-Meier was utilized in the analysis of survivorship with the end points as a revision for any component.

Results

All patients were reconstructed acetabulum at the anatomical location. HHS increased greatly for both groups (p = 0.18). No statistic difference was observed for the two groups in postoperative leg-length discrepancy (0.51 ± 0.29 cm for group A and 0.46 ± 0.39 cm for group B, p = 0.64 ), postoperative height of the hip center (2.25 ± 0.42 cm for group A and 2.09 ± 0.31 cm for group B, p = 0.13), and inclination of the cup (39 ± 4° for group A and 38 ± 3° for group B, p = 0.65 ). The rate of cup coverage for group B (94 ± 2%) was better than for group A (91 ± 5%), (p = .009). The rate of cup protrusio was 48 ± 4% for group A. For both groups, no statistical difference was observed in the cup diameter (p > .05), while group A showed less operation time than group B (p < .001). No complications were observed at the latest follow-up.

Conclusion

Controlled fracture of the medial wall to increase cup coverage by host bone at the anatomical location can act as an alternative technique for DDH Crowe II/III with the advantage of shorter operation time and less technically demanding.

Comparison of the long-term outcome of cemented Charnley low-friction arthroplasty with hybrid arthroplasty in patients with congenital hip disease

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.

A simple technique to strengthen the initial and mid-term to long-term stability of the cup during total hip arthroplasty in developmental dysplasia of the hip

Objectives:

To assess the effects of a technique of cup blocking screws combined with impaction bone grafting during total hip arthroplasty (THA) for patients with developmental dysplasia of the hip (DDH).

Methods:

From August 2011 to July 2015, 53 patients (59 hips) with DDH in our hospital were treated with THA using the technique of cup blocking screws combined with impaction particulate bone grafting. These patients were prospectively followed, and the clinical and imaging results were collected.

Results:

Harris hip score (HHS) was raised from 41.24 before surgery to 91.49 at the latest follow-up (p<0.001). Length discrepancy (LLD) was reduced from 28.97 mm before surgery to 6.08 mm after surgery (p<0.001). No loosening of the cup was detected at the last follow-up. The differences were insignificant in cup inclination and rate of cup coverage among the 3 groups of Crowe type II, type III, and type IV DDH (p>0.05).

Conclusion:

The technique of cup blocking screws combined with impaction particulate bone grafting is simple and reliable, and it not only simplifies the attainment of initial stability, but also strengthens the mid-term to long-term stability during THA in DDH.

An attempt to throw light on congenital hip disease terminology and anticipation of clinical outcomes when treated with total hip arthroplasty

The terminology of the wide spectrum of hip deformities seen during the neonatal, infantile and adult life period remains controversial, mainly due to the indiscriminate use of the terms dysplasia, subluxation, congenital hip disease, developmental hip disease, congenital dislocation, etc. This has a serious implication on the anticipation of clinical outcomes, complications and comparison of different reconstructive techniques when these patients are treated with total hip arthroplasty in adulthood. Journals, specialising in this field, should publish homogeneous series (type of the disease, reconstruction technique, implants) in order to clarify arguments and anticipate clinical outcomes.

Cementless total hip arthroplasty with extended sliding trochanteric osteotomy for high congenital hip dislocation: A retrospective study

Total hip arthroplasty (THA) for high congenital hip dislocation (CHD) is technically demanding. The purpose of this retrospective study was to evaluate the results of cementless THA combined with extended sliding trochanteric osteotomy. We also assessed whether chronic low back pain was relieved after surgery.The study included 19 patients (23 hips) with high CHD treated with cementless THA using extended sliding trochanteric osteotomy technique. Clinical and radiographic outcomes were evaluated.Harris Hip Score, WOMAC score, visual analog scale for low back pain and Trendelenburg sign were significantly improved (P < 0.01) compared with the preoperative. Average limb-length discrepancy in the 15 unilateral hips was reduced from 38.2 ± 7.9 mm to 6.7 ± 4.1 mm (P < 0.01). No dislocation, deep vein thrombosis, or infection occurred. Two patients (8.7%) developed sciatic nerve palsy. One (4.3%) developed symptomatic greater trochanteric bursitis. Two (8.7%) sustained proximal femur shaft fracture during implantation of the femoral component. All femoral components showed successful bony ingrowth at the final follow-up. No stem subsidence was detected. There was no acetabular loosening. Bony union of the reattached greater trochanter was obtained in all hips. Wire breakage occurred in 3 hips (13%).Cementless THA with extended sliding trochanteric osteotomy may be appropriate options for patients with high CHD.

The necessity to restore the anatomic hip centre in congenital hip disease

Total hip replacement (THR) is the treatment of choice for the patient suffering from end-stage hip osteoarthritis. In the presence of deformities due to congenital hip disease (CHD), THR is, in most of the cases, a difficult task, since the technique of performing such an operation is demanding and the results could vary. We present our experience and preferred strategies focusing on challenges and surgical techniques associated with reconstructing the dysplastic hip.

Satisfying Results of Primary Hip Arthroplasty in Patients With Hip Dysplasia at a Mean Followup of 20 Years

BACKGROUND

Developmental dysplasia of the hip (DDH) is a common cause of secondary osteoarthritis (OA) in younger patients, and when end-stage OA develops, a THA can provide a solution. Different options have been developed to reconstruct these defects, one of which is impaction bone grafting combined with a cemented cup. To determine the true value of a specific technique, it is important to evaluate patients at a long-term followup. As there are no long-term studies, to our knowledge, on THA in patients with DDH using impaction bone grafting with a cemented cup, we present the results of this technique at a mean of 15 years in patients with previous DDH.

QUESTIONS/PURPOSES

We wished to determine (1) the long-term probability of cup revision at a minimum followup of 15 years for cemented acetabular impaction bone grafting in patients with DDH; (2) the radiographic appearance of the bone graft and radiographic signs of implant loosening; and (3) the complications and pre- and postoperative Harris hip scores with cemented THA combined with impaction bone grafting in patients with previous DDH.

METHODS

Between January 1984 and December 1995 we performed 28 acetabular impaction bone grafting procedures for secondary OA believed to be caused by DDH in 22 patients; four patients died before 15 years, leaving 24 hips in 18 patients for retrospective analysis at a minimum of 15 years (mean, 20 years; range, 16-29 years). The diagnosis of DDH was made according to preoperative radiographs and intraoperative findings. All grades of dysplasia were included; five patients had Crowe Group I, eight had Group II, nine had Group III, and two had Group IV DDH. No patients were lost to followup. In all cases the acetabular defects were combined cavitary and segmental. Owing to the high number of deaths, we performed a competing-risk analysis to determine the probability of cup revision surgery.

RESULTS

The competing-risk analysis showed cumulative incidences at 15 and 20 years, with endpoint revision for any reason of 7% (95% CI, 0%-17%), whereas this was 4% (95% CI, 0%-11%) with endpoint revision of the cup for aseptic loosening. Three revision surgeries were performed. Two cup revisions were performed for aseptic loosening at 12 and 26 years. Another cup revision was performed owing to sciatic nerve problems at 2 years. A stable radiographic appearance of the graft was seen in 19 of the 25 unrevised hips. Four hips showed acetabular radiolucent lines and two showed acetabular osteolysis. None of the unrevised cups showed migration or radiographic failure. Postoperative complications included a pulmonary embolus and a superficial wound infection. The Harris hip score improved from 37 (range, 9-72) preoperatively to 83 (range, 42-99) at latest followup.

CONCLUSIONS

Cemented primary THA with the use of impaction bone grafting shows satisfying long-term results in patients with previous DDH. For future research it is important to evaluate this technique in a larger cohort with a long-term followup. Other techniques also should be evaluated at long-term followup to be able to compare different techniques in this important and specific patient group.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Medial Protrusio Technique in Cementless Total Hip Arthroplasty for Developmental Dysplasia of the Hip: A Prospective 6- to 9-Year Follow-Up of 43 Consecutive Patients

BACKGROUND

The medial protrusio technique may be used during total hip arthroplasty (THA) on patients with developmental dysplasia. However, studies have yet to determine whether a cementless cup can be sufficiently stable to withstand loading forces. This study aimed to assess the clinical and radiographic outcomes of this technique. Furthermore, we sought to determine the relationship between the rate of medial protrusion and the incidence of cup loosening.

METHODS

Thirty-nine patients (43 hips) underwent cementless THA between April 2006 and March 2009 by using the medial protrusio technique. These patients participated in a 6- to 9-year follow-up. Their clinical and radiographic data were gathered prospectively.

RESULTS

The average Harris Hip Score improved from 43.1 ± 15.4 points preoperatively to 91.9 ± 12.8 points at the final follow-up (P < .001). The mean height of hip center and the distance of hip center medialization were 2.4 ± 0.6 and 2.5 ± 0.9 cm, respectively. The rate of medial protrusion and the rate of cup coverage were 42.1 ± 12.4% and 96.8 ± 5.1%, respectively. The rate of medial protrusion ranged from 18.3% to 58.3% in 38 hips (group A) and from 61.3% to 68.9% in 5 hips (group B). None of the cups in group A loosened or failed, 2 failures occurred in group B (0% vs 40.0%; P = .011).

CONCLUSIONS

Developmental dysplasia was treated through THA using the medial protrusio technique, which easily achieves a sufficient superolateral host bony coverage of the cup and promotes socket reconstruction at the true acetabulum. The rate of medial protrusion of <60% may be necessary to obtain excellent clinical and radiographic midterm results.

Acetabuloplasty at the anatomic centre for treating Crowe class III and IV developmental hip dysplasia: a case series

INTRODUCTION

Total hip replacement in patients with developmental dysplasia of the hip (DDH) is a difficult technical procedure for surgeons to perform because of the potential for these patients to have severe anomalies in their bones and soft tissues.

MATERIALS AND METHODS

We performed acetabuloplasty in 54 hips from 44 patients by reaming the posterior wall of the native acetabulum and medialising the acetabular component to restore the anatomic centre of hip rotation using a small cup without bone grafting. Median time to post-surgery follow-up was 5 (range 2-14) years.

RESULTS

Prosthetic survival rates in patients after 2 and 5 years post hip replacement were 93% (50/54) and 89% (48/54), respectively. 4 patients required early revision because of malposition and instability of the acetabular cup. 3 patients with Crowe type IV dislocations had transient sciatic nerve palsy and 3 had deep vein thrombosis.

CONCLUSIONS

Placement of the acetabular shell using posterior bone stock to provide normal hip rotation is a successful alternative technique for acetabuloplasty in patients with DDH.

The results of monoblock stem with step-cut femoral shortening osteotomy for developmentally dislocated hips

INTRODUCTION

The main objective of this study was to evaluate the midterm results of cementless THA with the use of monoblock stems combined with step-cut femoral shortening derotational osteotomy for DDH.

MATERIALS AND METHODS

A total of 66 hips of 49 patients with Crowe type IV developmental hip dislocation, with a mean follow-up of 90 (range 26-207) months, were reviewed retrospectively. Subtrochanteric step-cut shortening osteotomy and monoblock femoral stems were used. The cup was placed in the true acetabulum in all cases. 21 hips had previous femoral valgisation osteotomies. Anteroposterior and lateral radiographs of both hips were obtained preoperatively and at the last follow-up examination. The Harris Hip Score (HHS) was used for pre- and postoperative clinical evaluation.

RESULTS

The mean HHS increased from 49 to 86 points. A total of 13 hips of 10 patients (the isolated acetabular component in 7 hips of 6 patients, the femoral component in 3 hips of 3 patients, and both components in 2 patients) were revised during the follow-up period. Dislocation occurred in 3 hips, deep periprosthetic infection in 2, superficial wound infection in 2, and femoral vein injury and sciatic nerve palsy in 1. Nonunion was observed in 3 osteotomy sites. 10-year survival probabilities of 91% for femoral components for all cases and 78% for acetabular components were found.

CONCLUSIONS

THA with subtrochanteric femoral shortening osteotomy was proven to be an effective technique for avoiding neurological complications for Crowe IV DDH. Cementless THA with the use of monoblock stems showed overall survival rates of 95% at 5 years and 85% at 10 years.

The Outcome of 241 Charnley Total Hip Arthroplasties Performed by One Surgeon 30 to 40 Years Ago

We present the outcome of 241 consecutive low friction arthroplasties (LFAs) performed by one surgeon (GH) 30 to 40 years ago. The overall survival rate at 30 years with revision for any reason or removal of the components as the end point was 53% (43.2-62.8%) when 40 hips remained in the study. Cox regression analysis for the possible risk factors of age, gender and diagnosis revealed higher risk of the overall failure in younger patients, and higher risk of failure due to loosening in younger patients and in those with congenital hip disease. Our follow-up study at 30 to 40 years following Charnley LFA can be used as a benchmark for comparison with the newer methods of total hip arthroplasty.

Does prior conservative surgery affect survivorship and functional outcome in total hip arthroplasty for congenital dislocation of the hip? A case-control study in 159 hips

INTRODUCTION

The results of total hip arthroplasty (THA) in congenital dislocation of the hip (CDH) are well known, but such is not the case for the impact of prior conservative surgery on THA function and survivorship. The present study compared THA in CDH with prior conservative bone surgery (BS group) versus no prior bone surgery (NBS group), to (1) assess the impact of prior conservative surgery on function and survivorship after THA, and (2) determine whether a particular type of conservative surgery affected function or survivorship.

HYPOTHESIS

Prior conservative surgery for CDH does not affect function or survivorship of subsequent THA.

PATIENTS AND METHODS

A multicenter retrospective case-control study analyzed 430 THAs in CDH patients (332 patients: 269 female, 63 male; mean age, 56 years [range, 17-80 years]) at a mean 13.2±5.4 years' follow-up (range, 1-29 years). The BS group included 159 hips (37%) (64 pelvic, 81 femoral and 14 combined pelvic and femoral osteotomies), and the NBS group 271 (63%). Groups were comparable for gender, age at surgery, Devane activity score, preoperative Postel Merle d'Aubigné (PMA) functional score and CDH radiographic type following Crowe.

RESULTS

At follow-up, PMA scores were comparable: BS, 16.8±1.4 (11-18); NBS, 16.9±1.5 (7-18). Fifteen-year survivorship censored for implant revision for whatever reason did not significantly differ: BS, 87% (95% CI: 83-91%); NBS, 89% (95% CI: 86-92%). Ten-year survivorship on the same criterion did not significantly differ according to type of prior surgery: hip shelf arthroplasty, 97% (95% CI: 95-99%); Chiari osteotomy, 100%; femoral osteotomy, 95% (95% CI: 92-98%); and Milch osteotomy 96% (95% CI: 93-99%).

DISCUSSION/CONCLUSION

Conservative surgery for CDH does not impair the functional results or survivorship of subsequent THA.

LEVEL OF EVIDENCE

III, case-control study.

Charnley low-friction arthroplasty in patients 35 years of age or younger

We evaluated the outcome of 41 consecutive Charnley low-friction arthroplasties (LFAs) performed by a single surgeon in 28 patients aged ≤ 35 years at operation between 23 and 36 years previously. There were 20 women and eight men with a mean age of 32 years (23 to 35) at surgery. Two patients (three hips) were lost to follow-up at 12 and 17 years post-operatively, respectively, and one patient (one hip) died at 13 years post-operatively. These patients were excluded from the final evaluation. The survival rate of the acetabular components was 92.7% (95% confidence interval (CI) 88.7 to 96.7) at ten years, 67.1% (95% CI 59.75 to 74.45) at 20 years and 53.2% (95% CI 45.3 to 61.1) at 25 years. For the femoral component the survival was 95.1% (95% CI 91.8 to 98.5) at ten years, 77.1% (95% CI 73.9 to 80.3) at 20 years and 68.2% (95% CI 60.7 to 75.8) at 25 years. The results indicate that the Charnley LFA remains a reasonable choice in the treatment of young patients and can serve for comparison with newer techniques and implants.

Cite this article: Bone Joint J 2013;95-B:1052–6.