Computed Tomographic Evaluation of Bone Stock in Patients With Crowe Type III Developmental Dysplasia of the Hip: Implications for Guiding Acetabular Component Placement Using the High Hip Center Technique.

BACKGROUND: We evaluated acetabular cup coverage (CC) and rim contact (RC) to evaluate the bone stock above the acetabulum for guiding acetabular component placement using the high hip center technique in patients with Crowe type III developmental dysplasia of the hip. METHODS: Using hip computed tomography and image processing software, pelvises were reconstructed digitally in 20 hips with Crowe type III developmental dysplasia of the hip. Mimicked cup was placed with anteversion angles of 0° (group I), 5° (group II), and 10° (group III) respectively. In each group, the cup was placed at the anatomical hip center at first, and then the cup was moved up to 40 mm vertically about the native rotation center with an increment of 2.5 mm at each step. CC and RC were calculated and documented with each movement. RESULTS: CC was 65.87%, 67.77%, and 68.98% for group I, group II, and group III at the native rotation center, and increased progressively to 86.45%, 85.85%, and 84.71% at 25 mm above. RC was 49.17%, 50.25%, and 51.92% for group I, group II, and group III at the native rotation center, and increased progressively to 86.87%, 86.39%, and 84.94% at 22.5 mm above. CC and RC were positively correlated, despite the different anteversion angles (r = 0.687 at 0°, 0.683 at 5°, and 0.645 at 10°; P < .001). CONCLUSION: Computed tomography analysis and computer stimulation demonstrate that it is feasible to use high hip center technique in Crowe type III hips.

Structural Allograft Supporting a Trabecular Metal Cup Provides Durable Results in Complex Revision Arthroplasty.

BACKGROUND: Revision total hip arthroplasty (THA) is challenging specially in the presence of severe acetabular bone deficiency. We report the use of a highly porous revision shell augmented by structural allograft to provide structural support and coverage to the acetabular component. METHODS: We identified 56 patients (58 hips) undergoing revision THA, where a trabecular metal revision cup was supported by structural allograft. Mean follow-up was 5.4 years (range 2-12 years). Preoperatively acetabular bone defects were classified as Paprosky 2A in 6 hips (10%), 2B in 12 hips (21%), 2C in 12 hips (21%), 3A in 11 hips (19%), and 3B in 17 hips (29%). Structural allograft configuration was classified as type 1 (flying buttress) in 13 hips, type 2 (dome support) in 23 hips, and type 3 (footings) in 17 hips, with 5 hips having combined configurations. RESULTS: All hips showed evidence of union between the allograft and host bone at latest follow-up, 14 hips had partial resorption of the allograft that did not affect cup stability. Three acetabular components demonstrated failure of ingrowth. Survivorship-free from radiographic acetabular loosening as end point was 94% at 5 years. The 5-year survivorship with revision for any reason as end point was 90%. CONCLUSION: Trabecular metal shells combined with structural bone allograft in revision THA demonstrate excellent midterm survival, with 94% of acetabular components obtaining stable union onto host bone at 5 years. Allograft restored bone stock with minimal resorption, and when it occurred did not alter the survivorship of the acetabular component.

Revision Total Hip Arthroplasty Using an Acetabular Reinforcement Ring With a Hook: A Precise Follow-Up, at Average 11.4 Years, of a Previous Report.

BACKGROUND: This study aims at determining the average long-term result of revision total hip arthroplasty (THA) using the acetabular reinforcement ring with a hook (ARRH) and bone grafting in severe acetabular bony defect. Expected 15-year survival of ARRH in revision THA is included in the study. METHODS: Retrospective review of 48 patients (48 hips) with follow-up duration of average 11.4 years (range, 6.1-21.4 years) was conducted. At each follow-up, Harris hip score was used to assess functional outcome, and radiographic acetabular component osteolysis was measured by DeLee and Charnley classification. Bone defects were assessed preoperatively and intraoperatively using American academy of orthopedic surgeons and Paprosky classification. The common modes of ARRH failures were evaluated. Bone consolidation, presence of heterotopic ossification, and complications such as infection and dislocation were recorded. RESULTS: The bone defects were varied and included cavitary, segmental, and combined defects without any pelvic discontinuity. Mean Harris hip score improved from 52.6 points preoperatively to 82.0 points postoperatively. Nine acetabular revisions and 3 stem revisions (2 concurrent with acetabular revisions and 1 isolated stem revision) were performed. There were 5 infected cases and 1 patient with recurrent dislocation. The 11.4-year survival of revision THA with ARRH was 71% as the end point for acetabular revision surgery for any reason. The expected 15-year survival of revision THA with ARRH was 60%. The most common failure mode of ARRH was superomedial migration followed by lateral migration. CONCLUSION: ARRH combined with bone grafting produces relatively good average long-term clinical results.

Revision Total Hip Arthroplasty using Allogenic Impaction Bone Grafts and Cemented Cup in Acetabular Bone Deficiency: Minimum Seven Years Clinical and Radiological Analysis

PURPOSE: This study examined the minimum seven years clinical and radiological results of revision total hip arthroplasty using an allogenic impaction bone graft and a cemented cup in an acetabular bone deficiency. MATERIALS AND METHODS: Fifty two revision total hip arthroplasty procedures performed on forty nine patients between March 1992 and June 1998 and followed for more than minimum seven years were examined. The clinical and radiological results were evaluated by Harris hip score and roentgenography including anterior-posterior view of pelvis and lateral view of operated hip. RESULTS: The mean Harris hip score was 47 points preoperatively, 81 points at three years after revision, and 84 points at seven years. The radiological evaluation revealed osseous union that trabeculated between grafted bone and host bone within four months in 47 hips, a complete grafted bone-cement radiolucent line of two millimeters or more in at least one zone in 5 hips at two years and in 7 hips at the seven year follow-up. CONCLUSION: We recommend the technique using an allogenic impaction bone graft and cemented cup to reconstruct an acetabular cavitary defect in revision total hip arthroplasty.

Morsellized Allograft and Acetabular Reconstruction Cage: Follow up of 2 to 9 years

We report the outcome of 32 patients who underwent total hip replacement (THR) augmented with morsellized fresh frozen femoral head allografts and acetabular reconstruction cages. Nine patients underwent primary THR and 23 patients underwent revision THR. Follow up ranged from two to 9 years. Two most common indications for the procedures as reported in literature were rheumatoid arthritis and aseptic loosening of the hip. All but one patient achieved good outcome with radiographs showing full incorporatio

Revision total hip arthroplasty using acetabular reinforcement device with grafting for the massive bone defects / 中国矫形外科杂志

[Objective]To introduce the technology of bone grafting with acetabular reinforcement device for the massive bone defects in the revision total hip arthroplasty.[Method]The massive acetabular bone defects were reconstructed in 8 cases from 2002 and 2007.The defects were classified according to the system of D'Antonio,ⅡB defects in 1 case,ⅡC defects in 2 cases,and Ⅲ defects in 5 cases.Methods:the reinforcement device with the morsellised impaction bone grafting in 3 cases,the reinforcement device with the morsellised impaction bone grafting and the structural autograft in 5 cases.Clinical and radiological evaluations were conducted for each patient.[Result]The follow-up duration averaged to 2.7 years,the Harris score were inoreased by 35 points in average.No hip required further revision of the acetabular component because of aseptic loosening.[Conclusion]The cavitary bone loss could be reconstructed by the bone-impaction grafting;the segmental bone loss could be reconstructed by the structural autograft.The acetabular reinforcement device can fix the grafted bone and support the cup.The massive periacetabular bone loss could be effectively reconstructed by reinforcement device with bone grafting.

Revision Total Hip Arthroplasty using Morselized Femoral Head Allograft and Cementless Cup in Acetabular Bone Deficiency / 대한정형외과학회잡지

PURPOSE: This study was aimed to evaluate the clinical and radiologic results of revision total hip arthroplasty using a cementless cup and a morselized femoral head allograft in acetabular bone deficiency. MATERIALS AND METHODS: From January 1992 to December 1999, the authors performed 37 revision total hip arthroplasties using morselized femoral head allografts and cementless cup. This study evaluated the clinical and radiologic results, at a mean follow-up of 50 months. We evaluated the Harris hip score clinically, and the displacement of acetabular cup by Yoder's criteria. Location and progression of radiolucent area within acetabular zone, which was defined by DeLee and Charnley was observed and recorded. RESULTS: Mean Harris hip score was improved from 50.6 preoperative to 89.2 at final follow-up. A radiolucent zone between host bone and graft bone was observed in 5 cases, and between graft bone and cup in 7 cases, but all of these were less than 2 mm. The change of cup angle more than 4 degrees were observed in 3 cases in Gross type 4, 4 mm superior migration of acetabular cup was observed in 1 case in Gross type 3 and 5 mm horizontal migration was observed in 1 case in Gross type 4. CONCLUSION: Although the early results in revision total hip arthroplasty have been encouraging to date except for Gross type 4, a more long term follow-up study with a larger size cases are needed.

Revision of total Hip Arthroplasty Using Allogenic Bone Graft in Acetabular Deficiency / 대한정형외과학회잡지

Patients with severe acetabular bony deficiency in total hip revision arthroplasties need the use of autogenous or allogenic bone grafts. The Authors performed 28 cases of total hip revision arthroplasties between June 1991 and January 1995 with femoral head allograft for acetabular bony deficiencies and evaluated the clinical and radiological results according to AAOS classification. The clinical result was evaluated by D'Aubigne and Postel score. The mean score was improved from 3.9 points to 5.1 points at follow-up. In radiological evaluation, osseous union of graft was achieved within 12 month and rerevision were performed in two cases (92.8% survival rates) but radiological radiolucent line in at least one zone was seen in five hips in two year follow up. In conclusion, the results of hemispherical microporocoat cup with allogenic bone in segmental or cavitary defect using with acetabular reinforcement ring in combined deficiency were encouraging to date. Success rate of allograft reconsruction of the acetabulum results from a variety of acetabular defect. In our studies, only 40% showed stable bony fixation over short period.