Total hip replacement with solid autologous femoral head graft for hip dysplasia

Femoral Head Autograft Can Reliably Reconstruct Dysplastic Acetabula Through the Direct Anterior Approach for Total Hip Arthroplasty

Background

Bone deficiencies in dysplastic acetabula create technical difficulties during total hip arthroplasty (THA). Bulk femoral head autograft (FHA) is one method to increase cup coverage and bone stock of the true acetabulum; however, only limited data exist on its efficacy through a direct anterior approach (DAA). This study aimed to evaluate the outcomes of FHA during THA via a DAA in dysplastic hips.

Methods

Retrospective review of 34 patients (41 hips) with hip dysplasia (Crowe I-III) who underwent primary THA via a DAA with FHA at a single institution was performed. Surgical procedures were performed on a traction table with intraoperative fluoroscopy and highly porous-coated cup placement in the true acetabulum. Patients were assessed clinically and radiographically at a minimum of 2 years postoperatively (range, 2 to 7).

Results

The average modified Harris Hip Score improved from 31.9 ± 10.8 to 94.1 ± 5.8, Merle d'Aubigné Hip Score from 7.5 ± 2.8 to 16.6 ± 1.1, and visual analog pain score from 7.9 ± 2.7 to 1.4 ± 1.4 (all P < .001). All hips had an “anatomic” inferomedial cup position postoperatively, with an average increase in horizontal coverage of 43.4%. Mean postoperative limb-length discrepancy improved from 21.8 ± 16.1 mm to 1.6 ± 5.7 mm (P < .001). There were no cases of revision THA, nor complications such as dislocation, infection, or osteolysis.

Conclusion

Reconstructing dysplastic acetabula (Crowe I-III) with FHA during THA can be successfully accomplished via the DAA with increased acetabular bone stock and accurate correction of limb-length discrepancy.

Biomechanical effect of metal augment and bone graft on cup stability for acetabular reconstruction of total hip arthroplasty in hip dysplasia: a finite element analysis

Background

Different methods of acetabular reconstruction with total hip arthroplasty (THA) for Crowe II and III of adult developmental dysplasia of the hip (DDH) acetabular bone defect have been implemented clinically. However, the biomechanical effect of different augmented materials for acetabular reconstruction in THA on shell stability has never been discussed.

Methods

In the present study, autologous bone graft (BG)and metal (Ti6Al4V) augment (MA) were simulated with several acetabular bone defect models of DDH in THA. The contact pressure and micromotion between the shell and host bone were measured for evaluating the shell stability using a finite element method.

Results

The peak contact stress between shell and host bone was higher in the MA situation (12.45 vs 8.71 MPa). And the load transfer path was different, for BG models, the high local contact stresses were found at the junction of bone graft and host bone while for MA models the concentrated contact stresses were at the surface of MA. The peak relative micromotion between shell and host bone was higher in the MA situation (12.61 vs 11.13 µm). However, the peak micromotion decreased in the contact interface of MA and cup compared to the BG models.

Conclusions

The higher micromotion was found in MA models, however, enough for bone ingrowth, and direct stronger fixation was achieved in the MA-cup interface. Thus, we recommended the MA can be used as an option, even for Crowe III, however, the decision should be made from clinical follow-up results.

Survivorship and functional outcome of a cemented acetabular component with bulk roof autograft for severe acetabular dysplasia: 12- to 23-year follow-up

AIMS

Primary aim was to determine survival of a cemented acetabular component with bulk roof autograft with a minimum of 12 years follow-up. The secondary aim was to determine the clinical outcome.

METHODS

A cohort of 62 consecutive patients (74 hips) undergoing cemented total hip arthroplasty with acetabular bulk roof autograft for acetabular dysplasia were retrospectively identified. The group consisted of 57 female patients (67 hips) and 5 male patients (7 hips) with a mean age at operation of 45 years. No patient was lost to follow-up, however 9 patients died had during the study period. The Oxford Hip Score (OHS), Forgotten Joint Score (FJS), EuroQol 5-Dimensional Score (EQ-5D), Short Form (SF-12) physical score and patient satisfaction were used to assess clinical outcome for patients with a surviving prosthesis.

RESULTS

The median follow-up was 16.6 (13.4-19.1) years. 6 revisions were performed during the follow-up period, all of which were due to aseptic loosening of the acetabular component. The all-cause Kaplan Meier survival rate for the acetabular component was 99% at 10 years, 95% at 15 years and 83% at 20 years. Neither age, gender, femoral osteotomy or polyethylene (UHMW vs. cross-linked) were significant predictors of aseptic revision of the acetabular component. There were no case of graft resorption and all grafts were radiologically incorporated. 45 patients were available for functional assessment at a mean follow-up of 18.2 years. The mean OHS was 37.8, FJS was 55.7, EQ5D was 0.73, and SF-12 physical component was 43.2. No patient was dissatisfied, with 2 patients reporting a neutral satisfaction, 7 stating they were satisfied and the remaining 36 were very satisfied.

CONCLUSIONS

A cemented acetabular component with bulk roof autograft for dysplasia offers excellent survival with good to excellent functional outcome with high patient satisfaction in the medium- to long-term.

The fate of femoral head autograft in acetabular reconstruction in dysplastic hips at midterm

PURPOSE

To evaluate the acetabular cup and graft survival in patients who underwent total hip arthroplasty (THA) with the diagnosis of dysplastic hip osteoarthritis and received a femoral head autograft due to acetabular coverage deficiency.

METHODS

Between January 2005 and December 2016, 83 hip prostheses of 80 patients who underwent THA using femoral head autografts and were followed up for at least 2 years were retrospectively evaluated. Seventy-four hips of the remaining 71 patients (57 female (80%)) were included. Mean patient age at surgery was 51 ± 16 (range 18-76) years. The mean follow-up duration was 76 ± 25 (range 25-161) months. Acetabular inclination and graft thickness, contact length, percentage of coverage, and graft resorption were examined on postoperative and final follow-up radiographs. The presence of a radiolucent area around the acetabular and femoral components indicating loosening was also evaluated.

RESULTS

The mean postoperative acetabular component inclination was 44 ± 5.1° (range 30-48°) with mean graft coverage of 34 ± 4.8% (range 24-46%). In all patients, autograft union with the pelvis was seen and the lateral overflow was remodeled. Fifteen patients (20%) underwent revision surgery due to aseptic acetabular component loosening in four, nontraumatic recurrent dislocations in eight, periprosthetic infection in one, acetabular component protrusion in one, and traumatic hip dislocation in one.

CONCLUSION

In patients with osteoarthritis secondary to developmental hip dysplasia, the use of femoral head autografts to eliminate acetabular coverage deficiency during THA achieves acceptable midterm postoperative radiological outcomes. Increased acetabular bone stock may be beneficial in possible future revision surgeries.

High Hip Center Technique in Total Hip Arthroplasty for Crowe Type II-III Developmental Dysplasia: Results of Midterm Follow-up

Objectives

We aimed to show the utility of high hip center technique used in patients with Crowe II–III developmental dysplasia of the hip at the midterm follow‐up and evaluated the clinical and radiographic results between different heights of hip center.

Methods

From December 2003 to November 2013, we retrospectively evaluated 69 patients (85 hips) with Crowe II–III dysplasia who underwent a high hip center cementless total hip arthroplasty. The patients were divided into two groups according to the height of hip center, respectively group A (≥ 22 mm and < 28 mm) and group B (≥28 mm). The survivorship outcomes and radiographic and clinical results, including the vertical and horizontal distances of hip center, femoral offset, abductor lever arm, cup inclination, leg length discrepancy, Trendelenburg sign, and limp were evaluated.

Results

The mean follow‐up time was 8.9 ± 1.8 years. The mean location of the hip center from the inter‐teardrop was 25.1 ± 1.6 mm vertically and 30.0 ± 3.8 mm horizontally in group A, and 33.1 ± 4.8 mm vertically and 31.4 ± 6.1 mm horizontally in group B. Eleven hips of group B showed a lateralization over 10 mm, and the same was shown in one hip in group A (P = 0.012). There were no statistically significant differences between two groups in postoperative femoral offset, abductor lever arm, leg length discrepancy and cup inclination. At the final follow up, the mean WOMAC and Harris hip score were significantly improved in both groups. Of the 85 hips, four hips in group A and three hips in group B showed a positive Trendelenburg sign. Additionally, four patients in group A and two patients in group B presented with a limp. No significant differences were shown regarding the Harris hip score, WOMAC score, Trendelenburg sign, and limp between two groups. One hip of group A was revised by reason of dislocation at 8.3 years after surgery. One hip of group B was diagnosed with osteolysis and underwent a revision at 8.1 years after surgery. The Kaplan–Meier implants survivorship rates at the final follow‐up for all‐causes revisions in group A and group B were similar (96.7% [95% confidence interval, 90.5%–100%] and 96.2% [95% confidence interval, 89.0%–100%], respectively).

Conclusions

The high hip center technique is a valuable alternative to achieve excellent midterm results for Crowe II–III developmental dysplasia of the hip. Further, between the groups with differing degrees of HHC, there were no significant differences in outcomes or survivorship in our study.

[Challenges of primary hip arthroplasty with high hip dislocation]

BACKGROUND

Endoprosthetic care of high hip dislocation is a surgical challenge. The hip anatomy is greatly altered in these patients, including a rather flat and small acetabulum with impaired bone quality and a relevant chance of a bony defect of the acetabular roof. Additionally, the front coverage and in some cases even the dorsal coverage of the hip are missing. The proximal femur is characterized with an increased antetorsion, a coxa valga position and an enlarged greater trochanter. The medullary cavity is narrowed, the offset is reduced, and the absolut leg length can be enlarged. Further anatomic variations can have been caused by previous surgeries.

AIM OF THE TREATMENT

The goal of the endoprosthetic care is the re-creation of a hip with an anatomic center of rotation, an anatomic offset and equal leg length.

TREATMENT

This can be achieved by a medial shift of the acetabular cup. An acetabular osteotomy including central cancellous bone graft or a bony graft to reinforce the acetabular roof might be necessary. In cases in which an anatomic acetabular cup placement is not possible, a more cranial placement can be done. Further strategies that are essential in several cases are shortening or re-orientation osteotomies of the femur, reaming of the medullary cavity and correct implant selection. Additionally, thorough soft tissue management is of main importance. Generally, the surgery should be well prepared preoperatively.

Uncemented acetabular components with femoral head autograft for acetabular reconstruction in developmental dysplasia of the hip: a concise follow-up report at a mean of twenty years

We previously reported the five to twelve-year results of total hip arthroplasty with an uncemented acetabular component and an autogenous femoral head graft in forty-four consecutive hips with developmental dysplasia. The goal of the present study was to report the implant survival rate, status of bone grafts, and clinical outcomes in thirty-five of these hips (in twenty-nine patients) followed for a mean of 21.3 years. Functional, radiographic, and survivorship results were examined. Radiographic analysis revealed an average cup inclination angle of 43° and a mean arc of cup coverage by the graft of 30°. The twenty-year survivorship free from acetabular revision was 66% (twelve acetabular revisions; eight since our previous report). Of the twelve revisions, nine were for liner wear and/or osteolysis, one was for a liner fracture, one was for aseptic loosening, and one was for instability. All bone grafts healed to the pelvis. The graft facilitated revision cup placement as no additional structural grafts or metal augments were required. We concluded that an uncemented porous-coated socket used in conjunction with a bulk femoral head autograft provides good long-term fixation and restores bone stock.

Autogenous impaction grafting in total hip arthroplasty with developmental dysplasia of the hip

Autogenous impaction grafting was performed to improve acetabular cup coverage in 68 patients (78 hips) with developmental dysplasia of the hip (DDH) after total hip arthroplasty, and the patients were then monitored for a mean duration of 5.5years. No cup revisions were required, and there was no radiographic loosening. The host-graft interface became indistinct by 6weeks after surgery, trabecular bone formation was seen by 12weeks, and definite trabecular reorientation was seen by 20months. At the last follow-up examination, the mean cup coverage was 97.7%, whereas mean coverage by bone grafting was 27.9%. Among 12 patients with most of the bone graft placed at the absolutely protruded area of the cup, the cup coverage provided by the bone graft decreased from 95.4% immediately after surgery to 20.7% by the final follow-up examination. Bone-particle grafting can provide a satisfactory integration speed and a low incidence of displacement and ectopic ossification.

High survivorship of cemented sockets with roof graft for severe acetabular dysplasia

BACKGROUND

Socket fixation in patients with acetabular dysplasia can be technically demanding but the use of structural grafts can help to reconstruct the original center of hip rotation. Because reported survival rates differ, construct survival seems to depend on the technique of graft preparation and fixation.

QUESTIONS/PURPOSES

What is the survivorship of cemented sockets with acetabular roof graft in patients with severe acetabular dysplasia? Do clinical scores equal those of patients without acetabular grafting?

METHODS

We retrospectively reviewed 62 patients (74 hips) who had undergone cemented THA with acetabular roof graft. Mean age at surgery was 45 years (range, 19-71 years). Revisions and radiographic failures were determined and clinical scores (Oxford, SF-12) were obtained and matched to a control group. Kaplan-Meier analysis was used to determine survivorship at a minimum followup of 5 years (mean, 10.4 years; range, 5-16 years).

RESULTS

Survivorship for all-cause revision was 98% (95% CI, 92.5%-100.0%) at 10 years followup. Two hips were revised for aseptic acetabular loosening and one hip for polyethylene wear. All grafts incorporated and no additional radiographic loosenings were seen. Patients with grafting had higher Oxford scores compared with the control group but other scores were equal.

CONCLUSIONS

In contrast to reported series and the common use of cementless cups in patients with developmental dysplasia of the hip, we found high survivorship of cemented sockets with roof graft in severe acetabular dysplasia at a mean followup of more than 10 years. These patients showed higher Oxford scores than patients in a control group. This technique that restores bone stock is a reasonable solution for often young patients with dysplasia.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Bulk femoral head autograft without decortication in uncemented total hip arthroplasty: seven- to ten-year results

Superolateral acetabular bone defect is a serious challenge in uncemented total hip arthroplasty for acetabular dysplasia. We report a bulk bone autografting technique without decortication of the acetabulum and femoral head contact surfaces in 22 joints. Mean follow-up time was 8.3 years, and survival rates were 100% for loosening and revision end points. The preoperative Japanese orthopedic association hip score increased from 49.5 to 94.0. Although trabecular bridging and graft remodeling occurred in all cases, complete trabecular reorientation was observed in only 15 joints. Eccentric polyethylene wear was observed in 8 of 22 joints, and osteolysis, in 1 joint. Our technique is easy to perform, and midterm results were favorable; thus, we conclude that it may be an effective option for bulk bone autografting.

The 15° face-changing acetabular component for treatment of osteoarthritis secondary to developmental dysplasia of the hip

We report the use of a 15° face-changing cementless acetabular component in patients undergoing total hip replacement for osteoarthritis secondary to developmental dysplasia of the hip. The rationale behind its design and the surgical technique used for its implantation are described. It is distinctly different from a standard cementless hemispherical component as it is designed to position the bearing surface at the optimal angle of inclination, that is, < 45°, while maximising the cover of the component by host bone.

High long-term survival of bulk femoral head autograft for acetabular reconstruction in cementless THA for developmental hip dysplasia

BACKGROUND

Deficient acetabula associated with acetabular dysplasia cause difficulty achieving adequate coverage of the acetabular component during THA. Autografting with the removed femoral head has been used for several decades to achieve better coverage, but the long-term benefits of this technique remain controversial, with some series reporting high rates of graft resorption and collapse.

QUESTIONS/PURPOSES

We evaluated the fate of bulk femoral head autograft for acetabular reconstruction in cementless THA for developmental hip dysplasia.

PATIENTS AND METHODS

We retrospectively reviewed 70 patients (83 hips) (68 women, two men) with a mean age of 57 years at index surgery. According to the classification of Crowe et al. for hip dysplasia, 10 hips were classified as Type I, 45 as Type II, 19 as Type III, and nine as Type IV. Minimum followup was 9 years (mean, 11 years; range, 9-14 years).

RESULTS

We observed no collapsed grafts. In all patients we observed disappearance of the host-graft interface and appearance of radiodense bands in the grafts bridging host iliac bone and at the lateral edges of the acetabular sockets; remodeling with definite trabecular reorientation was seen in 90%. The 10-year survival rate without acetabular revision for any reason was 94%. The mean Merle d'Aubigné and Postel hip score improved from a mean of 9.1 preoperatively to 17.2 at last followup.

CONCLUSIONS

Cementless THA combined with autologous femoral bone graft in patients with developmental dysplasia resulted in a high rate of survival. Structural bone grafting achieved a stable construct until osseointegration occurred. We believe the radiodense bands represent a radiographic sign of successful completion of repair of the deficient acetabulum. Congruous and stable contact of the cancellous portion of the graft to the host bed by impaction and use of improved porous cementless sockets may be associated with successful socket survival.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Large diameter metal-on-metal total hip arthroplasty for Crowe IV developmental dysplasia of the hip

The short-term results of middle-aged patients with severe developmental dysplasia of the hip treated with subtrochanteric femoral shortening and cementless large diameter metal-on-metal total hip arthroplasty were retrospectively evaluated. Clinical and radiological results of 15 hips of 13 patients with Crowe IV developmental dysplasia of the hip were enrolled in this study. The average follow-up period was 49 months (36-62 months). The average age of patients at the time of surgery was 45.5 years (range, 36-65 years). Radiographs were evaluated for component position, subsidence, loosening, and osteolysis. Intraoperatively, two patients had a small proximal femoral shaft split that was held with a cable wire. The average preoperative Harris hip score was 58; at 3 years, 82. Trendelenburg sign was negative in 11 hips at the last assessment. Loosening, subsidence, infection, dislocation, hypersensitivity and neurovascular complications were not observed. One hip had to be revised 1 year after surgery because of nonunion at the osteotomy site. Our study shows that large diameter metal-on-metal total hip arthroplasty, incorporating subtrochanteric femoral shortening, decreases dislocation rate and provides excellent results for the completely dislocated hip.

Minimum ten-year results of a porous acetabular component for Crowe I to III hip dysplasia using an elevated hip center

We conducted a retrospective study of the placement of porous-coated acetabular components using screws at more than 20 mm above the teardrop without structural bone graft for dysplastic hips to determine long-term outcome. Thirty hips (29 patients) were monitored for a mean of 15.2 years (range, 10.4-18.3 years) after surgery. Compared with 12 contralateral normal hips, the distance of the hip center from the teardrop was significantly high (26.8 +/- 4.8 and 13.4 +/- 2.7 mm P < .001); however, it was not laterally different (31. 5 +/- 5.1 and 31.7 +/- 5.0 mm). No acetabular components showed loosening. One metal shell was revised for wear and osteolysis. Morselized bone grafted in 25 hips was incorporated in all cases. Slight elevation of the hip center without lateralization in cementless cups fixed with screws was well tolerated for dysplastic hips.

Evaluation of the hip center in total hip arthroplasty for old developmental dysplasia

We describe the problems with positioning the hip center according to the severity of dislocation in 97 cementless total hip arthroplasty for developmental dysplasia of the hip. The mean location of the hip center from the interteardrop was 30.4 +/- 8.7 mm horizontally and 23.4 +/- 5.4 mm vertically. The presence of a limp correlated with a superior placement of the cup. Four cups were revised, 2 of which with a significant high hip center. The survival rate of the acetabular component was 95% at 12 years. Craniopodal repositioning was easy in class 1. In class 2, the cup was the largest. In class 3, the greatest variations of the hip center were found. In class 4, the smallest implants were necessary for positioning in the true acetabulum.

Migration of the Duraloc cup after 5 years

The Duraloc cup is a frequently used metal-backed, porous-coated, hemispherical, press-fit acetabular component. Published data on loosening rates are contradictory. In this study we investigated migration patterns with computer-assisted Einzel-Bild-Roentgen-Analyse (EBRA) of 67 Duraloc 100 cups. Cup migration and clinical scores were analysed over a 5-year follow-up period. Median total migration of the Duraloc 100 cup was 1.21 mm at 5 years. Seventy-five percent of implants were radiologically stable at 2 years and 90% at 4 years. One cup loosened aseptically at 60 months, requiring revision. Cup diameters > or = 54 mm migrated significantly more than cups < 54 mm in diameter (p = 0.029 at 4 years). There was a significant correlation between high polyethylene wear and further migrating cups within the first post-operative year (p = 0.035 at 12 months). Our analysis revealed significantly higher wear in males (p = 0.029 at 4 years). Radiological loosening at two years could be calculated using receiver-operating characteristic curve analysis, and 1.2 mm as an adequate threshold value (sensitivity = 100%, specificity = 89%).

Cementless acetabular reconstruction and structural bone-grafting in dysplastic hips

BACKGROUND

Studies of acetabular reconstruction with use of cement and bulk bone graft have demonstrated increasing rates of cup failure in patients with dysplastic hips seven years after total hip arthroplasty. Comparable data on the long-term results of bulk bone-grafting done in conjunction with cementless implants are limited. The aim of this study was to review the clinical and radiographic results of autologous bulk bone-grafting in conjunction with a cementless cup.

METHODS

From 1987 to 1992, forty-seven patients (forty women and seven men, with an average age of 50.4 years) who had developmental dysplasia of the hip underwent fifty-six total hip arthroplasties and received a structural graft in combination with a cementless Harris-Galante type-I cup. All patients were followed prospectively. In fifty-five hips, implant migration was measured with single-image radiographic analysis.

RESULTS

After an average duration (and standard deviation) of 10.2 +/- 2.9 years, three patients (four hips) had died. In the surviving patients, four implants had been revised and two had radiographic evidence of loosening. With use of revision and loosening as end points, the eleven-year survival rates were 91.6% and 88.9%, respectively. Of the fifty implants that had no loosening, fourteen had measurable cup migration, thirty-five had no migration, and one implant could not be measured. All migrations but one were progressive. With loosening used as the end point, the survival rate at eleven years was 100% for the implants with no migration; however, the survival rate for the cups that had migrated was 69.3% (p = 0.0012).

CONCLUSIONS

The eleven-year survival rate for the spherical press-fit cups in combination with bulk bone-grafting is satisfactory, given the complexity of these reconstructions. However, the difference between the survival of the implants that had migrated and those that had not was significant. We expect that the thirteen implants with progressive acetabular migration at the time of the latest follow-up are at risk for loosening, which will increase the revision rate for this series in the coming years.

Autogenous femoral head bone grafts for acetabular deficiency in total-hip arthroplasty for developmental dysplasia of the hip: long-term effect on pelvic bone stock

Twenty-eight primary total-hip arthroplasties in 23 patients performed with autogenous femoral head bone graft augmentation for developmental hip dysplasia were retrospectively reviewed at 8 to 15 years. Five sockets were revised for different reasons. At revisions, 3 grafts were healed, the other 2 had substantial resorption. Immediately postoperatively, the mean medial to lateral graft thickness at the level of the superior border of the socket was 33 mm. Radiographs a mean of 4.8 years after operation demonstrated this thickness decreased by a mean of 1 mm (range, 0-10 mm). At 11 years (range, 8-15 years), radiographs in unrevised hips showed no cases of substantial further graft resorption.

Total hip arthroplasty with a sliding iliac graft for acetabular dysplasia

We describe a new technique of reconstruction of the deficient acetabulum in cementless total hip arthroplasty. The outer iliac table just above the deficient acetabulum is osteotomised and slid downwards. We have termed this an iliac sliding graft. Between October 1997 and November 2001, cementless total hip arthroplasty with an iliac sliding graft was performed on 19 patients (19 hips) with acetabular dysplasia. The mean follow-up was 3.4 years (2 to 6). The mean pre-operative Harris hip score was 45.1 which improved significantly to 85.3 at the time of the final follow-up. No patient had post-operative abductor dysfunction. Incorporation of the graft was seen after two to three months in all patients. Resorption of the graft and radiolucencies were infrequent. This technique is a useful alternative to femoral head autografting when the patient's own femoral head cannot be used.

Bulk femoral-head autografting in uncemented total hip arthroplasty for acetabular dysplasia: results at 8 to 11 years follow-up

Acetabular dysplasia causes difficulty in achieving adequate coverage of the acetabular component during total hip arthroplasty (THA). Bulk femoral-head autografting is one technique that has been used to achieve better coverage of the acetabular component. Long-term follow-up studies have shown a significant failure rate when this technique has been used in conjunction with a cemented acetabular component; however, with uncemented components, early results have been encouraging. In our study, 15 patients with acetabular dysplasia underwent uncemented THA, during which bulk femoral-head autografts were used. At an average follow-up of 10 years, no cases required revision, and radiologically, the bone graft had united. Our results support the use of bulk femoral-head autografting in patients with acetabular dysplasia requiring hip arthroplasty.

Developmental hip dysplasia treated with total hip arthroplasty with a straight stem and a threaded cup

BACKGROUND

Operative strategies to overcome the anatomical anomalies in patients with osteoarthritis secondary to developmental dysplasia of the hip remain controversial. The objective of this study was to determine the outcomes of total hip replacement with a grit-blasted cementless threaded cup and a cementless straight stem in patients with developmental dysplasia.

METHODS

Ninety-three patients with developmental hip dysplasia who had been treated with a total of 121 cementless total hip arthroplasties were clinically assessed at a mean of 9.3 years. The acetabular reconstruction was done with a cementless threaded cup, which was medialized to ensure that at least one thread was anchored in the bone in order to achieve good primary stability. All radiographs were analyzed retrospectively.

RESULTS

Kaplan-Meier survivorship analysis, with radiographic evidence of aseptic loosening as the end point, predicted a survival rate of 97.5% for the acetabular component and 100% for the femoral stem at 9.3 years. The average Harris hip score for the unrevised hips improved from 34.0 points preoperatively to 84.1 points at the latest follow-up evaluation. The average total volume of polyethylene wear at the time of final follow-up was 73.6 mm(3).

CONCLUSIONS

These wear and loosening rates demonstrate that very good results were achieved in this relatively young patient population when the hip joint center had been properly restored, even when a small cup with a thin polyethylene liner had been used.

Arthroplasty in high grade congenital hip dislocation: Personal experience and review of the literature

Total hip arthroplasty (THA) in congenital high grade hip dislocation often represents a problematic issue. Reviewing their selected cases and literature data, authors focus on some key points for this demanding surgery. Most important steps are acetabular positioning and surgical approach (exposure and release). We used two different cups, the Zweymuller and the Wagner cup, with good primary stability. A Conus stem (Wagner) or an Alloclassic stem (in less displastic femoral shape) were used. We always performed this surgery as a one step procedure. In the same cases a shortening femoral osteotomy was performed to allow refractory reduction. Possible complications are discussed. (Hip International 2002; 2: 139-41).

Uncemented acetabular components with bulk femoral head autograft for acetabular reconstruction in developmental dysplasia of the hip: results at five to twelve years

BACKGROUND

Anterolateral acetabular bone deficiency is one of the technical problems associated with total hip arthroplasty in patients with developmental hip dysplasia. The purpose of this study was to evaluate the results of one method of acetabular reconstruction for hip dysplasia-placement of an uncemented socket in conjunction with a bulk femoral head autograft.

METHODS

Forty-four hips in thirty-five patients (twenty-nine female and six male; average age, thirty-nine years) with developmental hip dysplasia were treated with primary total hip arthroplasty with use of an uncemented porous-coated titanium cup fixed with screws and an autogenous bulk femoral head graft. The patients were followed clinically in a prospective fashion for five to 12.3 years (mean, 7.5 years), and radiographs were analyzed retrospectively.

RESULTS

Four acetabular components were revised: two, because of severe polyethylene wear and osteolysis; one, because of aseptic loosening; and one, because of fracture of the acetabular shell. The mean Harris hip score for the unrevised hips improved from 51 points preoperatively to 91 points postoperatively. No unrevised socket had definite radiographic evidence of loosening. Forty-three of the forty-four hips had no radiographic evidence of resorption of the graft or had radiographic evidence of resorption limited to the nonstressed area of the graft lateral to the edge of the cup.

CONCLUSIONS

This method of reconstruction provided reliable acetabular fixation and appeared to restore acetabular bone stock in patients with developmental hip dysplasia. We use this technique for patients with moderate anterolateral acetabular bone deficiency requiring total hip arthroplasty.

Structural bone grafting in arthroplasty for congenital hip dysplasia: 35 hips followed for 5-10 years

We assessed 35 hip arthroplasties in 30 patients with an average follow-up of 7 years. All patients suffered from secondary osteoarthrosis due to congenital dysplasia. The mean age at the time of surgery was 54 (19-77) years. Part of the femoral head used as a graft was fixed to the superolateral region of the acetabulum. A 100% bone coverage of the acetabular component was achieved initially. The mean support by the graft was 34%. The graft size, measured in the AP view, decreased on average 29% after 7 years. The resorption caused a reduction in cup coverage to 94%. There was no correlation between the clinical outcome and the graft size. Graft resorption occurred in the horizontal and vertical axes, but hardly affected the contact region with the iliac bone. Radiolucent lines according to DeLee were found in zone I in 4, zone II in 6 and zone III in 7 cases. The Harris Hip Score improved from 37-85 points. 1 revision was necessary 7 months postoperatively after cup dislocation.