Acetabular revision using a total acetabular allograft

The most challenging aspect of an acetabular revision is the management of severe bone loss, which compromises implant fixation and stability. We present a case of failed acetabular revision with extensive bone loss (Paprosky Type 3b) in a 50-year-old woman with rheumatoid arthritis, which was treated using total acetabular allograft. At a follow-up of 1 year and 3 months, the allograft had united with the host bone. This is the first report of the use of a total acetabular allograft for revision total hip arthroplasty in India. The total acetabular allograft allows the placement of the component closer to the normal hip center, provides initial stability for the acetabular component, and restores bone stock to the host pelvis.     

The Levine anterior approach for total hip replacement as the treatment for an acute acetabular fracture

The treatment of acetabular fractures in part relies on the selection of a specific surgical approach that allows for accurate reduction of fracture fragments. Moreover, these acetabular approaches were not developed for the insertion of a total hip replacement. Therefore, if a total hip arthroplasty is to be the treatment of an acute acetabular fracture, a single incision that permits reduction of the acetabular fracture fragments and ease of insertion of the arthroplasty components would be desirable. The Levine anterior approach provides both accesses to the anterior wall/column for reduction and fixation and to the femoral shaft for insertion of a total hip replacement. This paper describes that surgical technique and our initial clinical experience with this approach for acute acetabular fractures. A consecutive group of 10 patients with acetabular fractures, all involving the anterior wall/column with articular impaction (>50% of the acetabular roof) including 2 cases with an associated posterior hemitrans-verse component, were reviewed. After fracture reduction and fixation, a hybrid total hip replacement was implanted in all cases with an average acetabular component size of 56 mm (range 52-64). At a mean follow-up of 36 months (range 24-53), all fractures united, and all acetabular components remained fixed with no evidence of migration or loosening. There were 2 complications, a Brooker grade II heterotopic ossification and 1 postoperative anterior dislocation treated successfully with closed reduction and spica cast immobilization. The average Merle d'Aubigné hip score at latest follow-up was 16 (range 13-18). The Levine anterior approach is a reliable, safe, and efficient technique that permits early mobilization of patients with anterior wall/column acetabular fractures requiring a total hip replacement.     

Cementless total hip arthroplasty with femoral head bone grafting for hip dysplasia

Femoral head bone grafting was required to augment acetabular bone stock in 19 cases of hip dysplasia treated with cementless total hip arthroplasty. All acetabular grafts provided mechanical support for the cementless acetabular component. Radiographic evaluation of the fixation of the femoral components at an average of 3 years after surgery revealed an optimum appearance in all cases. All porous-coated acetabular components remained stable, but only one of six (17%) nonporous threaded acetabular components maintained stability. One threaded acetabular component has been revised for symptomatic loosening. Acetabular graft healing was suspected in 18 of 19 cases (95%). Significant graft resorption was observed only in the cases with unstable threaded acetabular components. The clinical scores were high. Cementless total hip arthroplasty with structural acetabular grafting and porous acetabular components appears to produce satisfactory short-term results.     

Destruction of acetabular bone caused by early failure of a constrained acetabular component

Use of a constrained acetabular component is 1 option for the treatment of dislocation after total hip arthroplasty. We report a case of a constrained acetabular component that resulted in postoperative early fixation loss and required revision 12 days after primary surgery. The superoposterior wall of the acetabulum was destroyed by the migrated acetabular component. Sharp ends of screws with a metal shell may have plowed up acetabular bone gradually after fixation loss of the component. This failure illustrates the potential risk of using a constrained acetabular component for total hip arthroplasty.     

Results of total hip reconstruction using acetabular mesh in patients with central acetabular deficiency

Fifty-three patients (54 hips) treated with cemented total hip reconstruction with the aid of an acetabular mesh made of Vitallium (Howmedica Inc., Rutherford, New Jersey), a cobalt-chrome molybdenum alloy, to reinforce the medial cement for deficient bone stock in the central acetabular region, were evaluated at an average follow-up period of 6.8 years (range, five to ten years). Thirty of these patients (30 hips) were treated with revision operations for either failed cup arthroplasty (ten hips), failed endoprosthesis (six hips), or failed total hip arthroplasty (14 hips) and presented difficult problems for acetabular reconstructions. Although none of the hips required reoperations for acetabular loosening, three patients showed roentgenographic evidence of acetabular component migration, and three others showed signs of impending failure of fixation of the acetabular component. The overall mean Harris hip rating improved from a mean of 43 points preoperatively to 87 points at follow-up evaluations. The extent of bone loss in the central acetabular region had the greatest influence on the results of acetabular fixation at the follow-up evaluation. None of the hips with intact medial acetabular cortex had roentgenographic evidence of failure of fixation, while 14% of the hips with medial cortical defects measuring less than 1 cm, and 75% of the hips with larger defects developed acetabular component loosening. The results of total hip reconstruction using acetabular mesh were unsatisfactory in patients with moderate or severe central acetabular bone loss and defects through the medial wall.(ABSTRACT TRUNCATED AT 250 WORDS)     

A randomised study comparing resection of acetabular bone at resurfacing and total hip replacement

We have undertaken a prospective, randomised study to compare conservation of acetabular bone after total hip replacement and resurfacing arthroplasty of the hip. We randomly assigned 210 hips to one of the two treatment groups. Uncemented, press-fit acetabular components were used for both. No significant difference was found in the mean diameter of acetabular implant inserted in the groups (54.74 mm for total hip replacement and 54.90 mm for resurfacing arthroplasty). In seven resurfacing procedures (6.8%), the surgeon used a larger size of component in order to match the corresponding diameter of the femoral component. With resurfacing arthroplasty, conservation of bone is clearly advantageous on the femoral side. Our study has shown that, with a specific design of acetabular implant and by following a careful surgical technique, removal of bone on the acetabular side is comparable with that of total hip replacement.     

Computed tomography-based navigation to determine the socket location in total hip arthroplasty of an osteoarthritis hip with a large leg length discrepancy due to severe acetabular dysplasia

For osteoarthritis hips due to severe acetabular dysplasia such as Crowe type 3 or 4, placement of the socket is a difficult procedure in total hip arthroplasty. Because the acetabular bone stock is poor, suitable location for the socket is very limited with respect to achieving good coverage with the host bone. A 51-year-old woman who had an osteoarthritis hip with a large leg length discrepancy due to severe acetabular dysplasia required total hip arthroplasty. The purpose of the total hip arthroplasty was to improve the hip disorder as well as to reduce the leg length discrepancy to achieve good gait function. We present technical solutions to aid the surgeons in placing the acetabular socket at the proper location by using computed tomography-based navigation system.     

Cementless acetabular reconstruction after acetabular fracture.

BACKGROUND: Total hip arthroplasty in patients with posttraumatic arthritis has produced results inferior to those in patients with nontraumatic arthritis. The use of cementless acetabular reconstruction, however, has not been extensively studied in this clinical context. Our purpose was to compare the intermediate-term results of total hip arthroplasty with a cementless acetabular component in patients with posttraumatic arthritis with those of the same procedure in patients with nontraumatic arthritis. We also compared the results of arthroplasty in patients who had had prior operative treatment of their acetabular fracture with those in patients who had had prior closed treatment of their acetabular fracture. METHODS: Thirty total hip arthroplasties were performed with use of a cementless hemispheric, fiber-metal-mesh-coated acetabular component for the treatment of posttraumatic osteoarthritis after acetabular fracture. The median interval between the fracture and the arthroplasty was thirty-seven months (range, eight to 444 months). The average age at the time of the arthroplasty was fifty-one years (range, twenty-six to eighty-six years), and the average duration of follow-up was sixty-three months (range, twenty-four to 140 months). Fifteen patients had had prior open reduction and internal fixation of their acetabular fracture (open-reduction group), and fifteen patients had had closed treatment of the acetabular fracture (closed-treatment group). The results of these thirty hip reconstructions were compared with the intermediate-term results of 204 consecutive primary total hip arthroplasties with cementless acetabular reconstruction in patients with nontraumatic arthritis. RESULTS: Operative time (p < 0.001), blood loss (p < 0.001), and perioperative transfusion requirements (p < 0.001) were greater in the patients with posttraumatic arthritis than they were in the patients with nontraumatic arthritis. Of the patients with posttraumatic arthritis, those who had had open reduction and internal fixation of their acetabular fracture had a significantly longer index procedure (p = 0.01), greater blood loss (p = 0.008), and a higher transfusion requirement (p = 0.049) than those in whom the fracture had been treated by closed methods. Eight of the fifteen patients with a previous open reduction and internal fixation required an elevated acetabular liner compared with one of the fifteen patients who had been treated by closed means (p = 0.005). Two of the fifteen patients with a previous open reduction and internal fixation required bone-grafting of acetabular defects compared with seven of the fifteen patients treated by closed means (p = 0.04). The thirty patients treated for posttraumatic arthritis had an average preoperative Harris hip score of 41 points, which increased to 88 points at the time of follow-up; there was no significant difference between the open-reduction and closed-treatment groups (p = 0.39). Twenty-seven patients (90%) had a good or excellent result. There were no dislocations or deep infections. The Kaplan-Meier ten-year survival rate, with revision or radiographic loosening as the end point, was 97%. These results were similar to those of the patients who underwent primary total hip arthroplasty for nontraumatic arthritis. CONCLUSIONS: The intermediate-term clinical results of total hip arthroplasty with cementless acetabular reconstruction for posttraumatic osteoarthritis after acetabular fracture were similar to those after the same procedure for nontraumatic arthritis, regardless of whether the acetabular fracture had been internally fixed initially. However, total hip arthroplasty after acetabular fracture was a longer procedure with greater blood loss, especially in patients with previous open reduction and internal fixation. Previous open reduction and internal fixation predisposed the hip to more intraoperative instability but less bone deficiency.     

Cementless acetabular fixation in total hip arthroplasty using polyglycolide-lactide screws: an in vivo canine study

Bone ingrowth into cementless acetabular components was evaluated in a canine total hip arthroplasty model, comparing components initially stabilized with polyglycolide-lactide screws with those initially stabilized with titanium screws. The acetabular shell was anchored with 2 polyglycolide-lactide screws in 16 dogs and with 2 titanium screws in 12 dogs. The dogs were followed and sacrificed at 7 weeks, 14 weeks, 10 months, or 15 months. Histomorphometric analysis of bone ingrowth into the weight-bearing dome of the acetabular shell was conducted. No difference was detected in mean bone ingrowth into the acetabular shell comparing the 2 screw groups. The results of this study do not support a significant advantage to the use of biodegradable screws for the initial stabilization of cementless acetabular components in canine total hip arthroplasty.     

Acetabular revision with morsellised allogenic bone graft and a cemented metal-backed component

Failure of total hip arthroplasty with acetabular deficiency occurred in 55 patients (60 hips) and was treated with acetabular revision using morsellised allograft and a cemented metal-backed component. A total of 50 patients (55 hips) were available for clinical and radiological evaluation at a mean follow-up of 5.8 years (3 to 9.5). No hip required further revision of the acetabular component because of aseptic loosening. All the hips except one had complete incorporation of the allograft demonstrated on the radiographs. A complete radiolucent line of > 1 mm was noted in two hips post-operatively. A good to excellent result occurred in 50 hips (91%). With radiological evidence of aseptic loosening of the acetabular component as the end-point, the survivorship at a mean of 5.8 years after surgery was 96.4%. The use of impacted allograft chips in combination with a cemented metal-backed acetabular component and screw fixation can achieve good medium-term results in patients with acetabular bone deficiency.     

Acetabular reinforcement in total hip replacement

In 21 cases of severe secondary protrusio acetabuli with extensive or total destruction of the acetabular cortical structures, the double anchorage of conventional polyethylene cups with nine Müller acetabular reinforcement rings and 12 Burch-Schneider anti-protrusio reinforcement cages was carried out. They were applied in combination with reconstructive surgery of cancellous bone in three primary total hip replacements and in 18 revision operations for loosened acetabular cups following total arthroplasties. Indication for and technique of the acetabular reinforcement are described. The radiological and clinical results in 21 patients followed up were satisfactory. They confirm the efficiency of these screw-fixed reinforcement implants for the solid fixation of the plastic cup in patients with extreme acetabular deficiencies.     

Birmingham hip resurfacing: is acetabular bone conserved?

Hip resurfacing is a bone-conserving procedure with respect to proximal femoral resection, but there is debate in the literature as to whether the same holds true for the acetabulum. We have investigated whether the Birmingham hip resurfacing conserves acetabular bone. Between 1998 and 2005, 500 Birmingham hip resurfacings were performed by two surgeons. Between 1996 and 2005 they undertook 700 primary hip replacements, with an uncemented acetabular component. These patients formed the clinical material to compare acetabular component sizing. The Birmingham hip resurfacing group comprised 350 hips in men and 150 hips in women. The uncemented total hip replacement group comprised 236 hips in men and 464 hips in women. Age- and gender-matched analysis of a cohort of patients for the sizes of the acetabular components required for the two types of replacement was also undertaken. Additionally, an analysis of the sizes of the components used by each surgeon was performed. For age-matched women, the mean outside diameter of the Birmingham hip resurfacing acetabular components was 2.03 mm less than that of the acetabular components in the uncemented total hip replacements (p < 0.0001). In similarly matched men there was no significant difference (p = 0.77). A significant difference was also found between the size of acetabular components used by the two surgeons for Birmingham hip resurfacing for both men (p = 0.0015) and women (p = 0.001). In contrast, no significant difference was found between the size of acetabular components used by the two surgeons for uncemented total hip replacement in either men or women (p = 0.06 and p = 0.14, respectively). This suggests that variations in acetabular preparation also influence acetabular component size in hip resurfacing.     

Ten- to 15-Year Clinical and Radiographic Results for a Compression Molded Monoblock Elliptical Acetabular Component

The aim of this study was to report the long-term results from a previously published midterm follow-up of a titanium monoblock, elliptical acetabular component. A total of 258 primary total hip arthroplasties (212 patients) with a monoblock, acetabular component were followed up for a mean period of 11.1 years (10-15). Average yearly wear rate was 0.08 mm/y (0.0009-0.32). Acetabular radiolucencies were present in 6 hips (2.4%); all were nonprogressive and present in acetabular zone I. Acetabular osteolysis was present in 5 patients (5 hips, 1.9%); all cups were stable. Four acetabular components were revised, 3 because of recurrent instability. No acetabular components were revised for polyethylene wear or dissociation, acetabular osteolysis, loosening, or deep infection. This monoblock design demonstrates excellent long-term survival and low rate of osteolysis.     

Intermediate- to Long-Term Results After Hybrid Total Hip Arthroplasty in Patients With Rheumatoid Arthritis

There have been few reports describing intermediate- to long-term results after hybrid total hip arthroplasty in patients with rheumatoid arthritis. We followed up 52 hips in 44 patients aged 5 men and 39 women, with a mean of 11.5 years (range, 5-23.5 years). Revisions had been performed in 6 hips in 6 patients: 1 both acetabular and femoral components for infection, 1 acetabular component for aseptic loosening, 3 acetabular components for recurrent dislocation, and 1 acetabular component for dislodgement of the polyethylene liner from the metal shell. None of other acetabular or femoral components were revised or found to be loose at the final follow-up. Although postoperative dislocation remains a concern, hybrid total hip arthroplasty had an acceptable result in patients with rheumatoid arthritis.     

Radiographic comparison of grit-blasted hydroxyaptite and arc-deposited hydroxyapatite acetabular components. A four-year follow-up study

High rates of aseptic loosening have been reported for microstructured hydroxyapatite-coated acetabular components. A macrostructured component surface (arc-deposition) not only improves resistance to shear forces experienced by the acetabular component and increases initial stability, but also provides channels for bone ingrowth. The purpose of this investigation was to radiographically compare a series of grit-blasted (microstructured) and arc-deposited (macrostructured) hydroxyapatite-coated acetabular components. A minimum 4-year retrospective radiographic analysis of acetabular components was performed on a total of 50 total hip arthroplasties. At 4 years, arc-deposited components were associated with fewer radiolucent lines in all Charnley zones, particularly Charnley zone III. While the 4-year results for arc-deposited hydroxyapatite acetabular components are superior to their microstructured predecessors, long-term results are still unknown.     

Total hip replacement for acetabular fractures. Results in 121 patients operated between 1983 and 2003

Total hip replacement has an important role in the treatment of acetabular fractures. Immediate total hip arthroplasty is only indicated for some rare cases but late reconstruction is performed more frequently and may follow failed non-operative or operative treatment of the original acetabular fracture. INTRODUCTION: The purpose of this study is to determine the results of the use of total hip replacement for the treatment of acetabular fractures and to compare the results of the early and late reconstruction group. MATERIALS AND METHODS: 121 acetabular fractures treated with total hip arthroplasty between 1983 and 2003 at the University Hospitals Gasthuisberg in Leuven, Belgium were retrospectively studied. The patients were divided into two groups. In the "early reconstruction group" total hip arthroplasty was performed as primary treatment of the acetabular fracture. In the "late reconstruction group": total hip arthroplasty was performed following failed operative or non-operative treatment of the acetabular fracture. The indications for total hip arthroplasty and the surgical technique in both the early and late reconstruction group were compared. Secondly, complications were reviewed in both groups and a functional scoring system was applied for each patient. RESULTS: Primarily there was a significant difference in the age of the patient population of each group with a predominance for older patients in the early reconstruction group. Secondly, less revisions were performed in the early reconstruction group: 8% compared to 22% in the late reconstruction group. DISCUSSION: The results obtained in our patient groups were compared to the results found in literature by a Medline search. In general, our results were comparable to the results found in literature but a remarkable difference was found between different authors. CONCLUSION: Total hip replacement for acetabular fractures is rarely indicated in the acute phase. After failed treatment of an acetabular fracture, total hip replacement has to be considered as a salvage procedure. In both cases, one may not forget total hip arthroplasty is a severe intervention associated with a high number of complications.     

髋臼假体位置对人工股骨头应力分布的影响

目的探讨髋臼假体不同放置位置对髋关节置换术后人工股骨头压应力的生物力学影响。方法对8具尸体16侧髋关节标本按照全髋关节置换术髋臼的处理原则，制作16种人工髋臼放置的位置，共分成两组：髋臼向内侧位移组，从解剖位置起间隔2mm，递增至14mm，共8髋；靛臼向上方位移组，从解剖位置起间隔2mm，递增至14mm，共8髋。应用电阻应变片在生物力学试验机上测定各标本在轴向1000N载荷下人工股骨头的应变数据，记录人工股骨头所承受的压应力值。结果（1）髋臼向内侧位移组：髋臼假体位置每向内位移2mm，人工股骨头承受的压应力就增加，位移越多，股骨头承受的压应力增加就越明显，位移超过6mm后，压应力呈明显快速增加趋势；（2）髋臼向上方位移组：髋臼假体位置每向上位移2mm，除上移6mm应力值小于上移4mm外，人工股骨头承受的压应力总体趋势是增加，且上移超过8mm后，人工股骨头压应力值开始明显增加；（3）在相同位移情况下，向内位移时人工股骨头压应力明显大于向上位移。结论髋臼中心无论是向内或向上位移，股骨头承受的压应力均增加，且位移幅度越大，压应力增加越明显；向上位移6mm时，人工股骨头承受的应力值均小于前后位移点，未排除此位点是一应力缓冲点的可能。     

Cementless acetabular cup: 6-year follow-up

The aim of this study was to evaluate the long-term outcome of cementless acetabular cups used in primary total hip arthroplasty. From November 1993 to December 1998, we implanted 403 cementless acetabular cups. Here we present a review of 160 patients (97 women) who received cementless acetabular cups with a porous-coated surface. The average postoperative follow-up period was 6 years (range, 4–8 years). The mean age of patients was 68 years for cemented stems (65 hips) and 59 for uncemented stems (95 hips). A total of 104 patients received ceramic-polyethylene components and 56 had ceramic-ceramic components. One patient presented acetabular migration and needed revision after 5 months indicating a failure rate of 0.6%. We believe that our results provides quite good perspectives for future work with this acetabular component. Received: 3 May 2002, Accepted: 10 May 2002     

Use of an anatomical acetabular component for treatment of iliopsoas impingement

Iliopsoas impingement is a known cause of pain after total hip arthroplasty. The author reports on a patient with iliopsoas impingement due to prominence of the anterior aspect of her acetabular hip arthroplasty component successfully treated with revision to an anatomically designed acetabular implant. Use of such an anatomically designed acetabular implant may prove to be beneficial in selected patients with iliopsoas impingement.     

Acetabular fractures in the UK. What are the numbers?

We have established a nationwide directory of the specialist surgical units and their Lead Consultants with expertise in acetabular fracture surgery throughout the UK. Our directory has facilitated an estimation of the total numbers of operative acetabular fracture cases managed annually in the UK, as reported by those actually providing this specialist service. Previously the total number of acetabular injuries admitted and operated on in the UK was not known and there was no directory of acetabular surgeons in the UK. The introduction and accuracy of the OPCS codings will have massive financial implications for the DoH at a local and national level in the planning and provision of adequate health care resources. We have performed a questionnaire study to validate the DoH data for acetabular fracture surgery. Data was compiled using the ICD-10 for diagnosis of fracture of the acetabulum, and the OPCS-4 codes for the surgical procedures used for fracture fixation for the year 2003-2004. The Department of Health (DoH) data identified 44 units that had OPCS-4 coding for acetabular fracture fixation. We had a 95% (42 out of 44 units) response to our questionnaire. A total of 9 units contacted had actually performed no surgery, whereas the DoH coded these as having performed a maximum of 35 cases. The DoH data showed a total of 1825 admissions to 311 NHS hospitals for acetabular fractures, including 258 operative cases performed in 44 NHS hospitals in the UK. Our study has found that 748 acetabular fracture fixation cases were performed at 33 NHS hospitals in the UK in this study period. The total difference between the DoH operated cases and those confirmed by our study was 490. The hospital care for an operative acetabular fracture case may cost approximately 14,830, pounds if the actual numbers are under-reported to or by the DoH are 490, then approximately 7,266,700 pounds has been lost by these centres due to incorrect proportioning of resources.