Severe Acetabular Bone Loss Research Articles

Treatment of Large Acetabular Defects: A Surgical Technique Utilizing Impaction Grafting into a Metallic Mesh

Revision total hip arthroplasty in cases with severe acetabular bone loss is challenging. In the presence of combined cavitary and segmental defects without superior acetabular coverage, reconstructions with a structural acetabular allograft protected by a cage or a custom-made triflange cage have been the treatment of choice. The current paper describes an impaction grafting into a mesh for uncontained defects in revision total hip arthroplasty. After restoring containment with a mesh fixed with small fragment screws, defects were restored using impaction grafting combined with a cemented all-polyethylene cup. Fourteen consecutive acetabular impaction graftings were performed by two surgeons. All patients had a type 3B defect according to the Paprosky classification. No re-revisions or radiographic failure was detected in the early follow-up period. Impaction grafting into a mesh is an interesting treatment option to restore bone in combined cavitary and segmental defects.

Radiographically Undetectable Periprosthetic Osteolysis With ASR Implants

Patients with ASR implants (resurfacing and large-diameter (XL) metal-on-metal (MoM) total hip arthroplasty), even if asymptomatic and with a stable prosthesis, may present extremely high blood metal ion levels. We report on a consecutive series of fourteen ASR revisions, focusing on osteolysis and their radiographic correspondence and their correlation with blood metal ion levels. At revision, seven hips revealed severe periacetabular osteolysis which was radiographically undetectable in six and asymptomatic in five. Seven hips with no acetabular osteolysis had significantly lower serum Cr and Co ion concentrations (respectively 25.2, 41.1 μg/l) compared to the seven hips with severe acetabular bone loss (respectively 70.1, 147.0 μg/l). Elevated blood metal ion levels should be considered as a warning of undetectable and ongoing periprosthetic osteolysis in asymptomatic patients with ASR prosthesis.

Bulk Allograft Using the Proximal Part of the Femur for a Posterosuperior Acetabular Defect: A Case Report.

Acetabular reconstruction in revision total hip arthroplasty can be quite challenging, especially in the presence of substantial acetabular osseous defects. Reconstruction of the acetabulum with severe acetabular bone loss using hemispherical cups with screw augmentation1, antiprotrusio cages2, metal augments3, bulk allografts4, and combinations of these methods2-6 has been described. We report the use of an ipsilateral proximal portion of a femur as a novel allograft source in addition to hemispherical, cementless acetabular reconstruction with screws in the treatment of a Paprosky type-IIIA acetabular defect. The patient was informed that data concerning this case would be presented for publication, and she provided consent. A fifty-seven-year-old woman had a history of a right primary total hip replacement with an uncemented component in 1988 to treat osteoarthritis. This was followed by acetabular revision for isolated aseptic loosening in 2003. The patient presented to the senior author in 2004, eleven months postrevision, with symptoms of increasing inability to bear weight and progressive right hip and buttock pain. Radiographs demonstrated a stable uncemented femoral component as well as gross acetabular loosening and medioinferiorly placed screws (Fig. 1). The patient had a large radiolucency in the area of zone three and superolateral migration of the acetabular component. Preoperative radiographs, including an anteroposterior pelvic view, anteroposterior and lateral views of the hip, and Judet views, demonstrated substantial osseous loss to the posterior wall, posterior column, and acetabular dome. Figure 2 is a representation of the acetabular bone loss seen at the time of revision. The preoperative evaluation included normal serology (C-reactive protein level <3 mg/dL and an erythrocyte sedimentation rate of 10 mm/h), and hip aspiration yielded a negative culture. Fig. 1 Anteroposterior pelvic radiograph demonstrates a grossly unstable right acetabular component with superolateral migration of the cup …

High Failure Rate with the GAP II Ring and Impacted Allograft Bone in Severe Acetabular Defects

Reconstruction rings and bone allografts have been proposed to manage severe acetabular bone loss. However, a high early failure rate of the Graft Augmentation Prosthesis (GAP) II reinforcement ring (Stryker Orthopaedics, Mahwah, NJ, USA) has been reported in one small series. We therefore determined (1) the survival of this device in combination with impacted morselized allograft bone in patients with severe defects and (2) the complication rate. We retrospectively reviewed 24 patients (21 aseptic and three septic) with severe acetabular bone loss (10 hips with Type III defects and 14 with Type IV defects according to the American Academy of Orthopaedic Surgeons classification). We determined function and numbers of failures. The minimum followup was 24 months (mean, 34 months; range, 24-72 months). At latest followup, the reconstruction had failed in nine of the 24 patients: six with aseptic loosening, three with infection. The average postoperative Merle d'Aubigné-Postel score of the patients whose reconstructions had not failed was 16.6 points; at latest followup, these patients had radiographic evidence of incorporation and consolidation of bone allografts. Seven of the nine patients whose reconstructions had failed underwent reoperation. Fatigue fracture of the ring at the plate-cup union occurred in five patients at an average of 45 months postoperatively. All patients with failed reconstructions who underwent reoperation were treated with Trabecular Metal(™) (Zimmer Inc, Warsaw, IN, USA) cups and were functioning well at latest followup. We observed a high rate (37%) of early catastrophic failures of the GAP II reconstruction ring, particularly in patients with Type IV defects. Due to this high failure rate, we have abandoned its use. Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Acyclic Acetabular Roof Reconstruction for Severe Superior Segmental Acetabular Bone Loss in 2-Stage Surgery for Infected Hip Arthroplasty

Ensuring the stability of a cemented PROSTALAC cup (Depuy, Warsaw, Ind) in the presence of severe superior acetabular segmental deficiency is critical to the success of the first-stage surgery. We present an illustrative case and the surgical technique required to achieve this.

Trabecular Metal Used for Major Bone Loss in Acetabular Hip Revision

The purpose of this study was to evaluate the outcome of trabecular metal (TM) acetabular components used in revision hip arthroplasty with major bone deficiency. We retrospectively reviewed the records of 46 patients undergoing revision hip arthroplasty with severe acetabular bone loss. Clinical outcomes were assessed using Harris Hip Score, Western Ontario and McMaster Universities, and Short-Form 12. Mean follow-up was 50 months. All patients had Paprosky type IIc or III acetabular bone deficiency. Major complications included 1 infection, 2 dislocations, and 1 arterial bleeding. Average Harris Hip Score was 78.2. Short-Form 12 scores were within population-based age-matched averages. Western Ontario and McMaster Universities scores were mainly in the 2 lowest disability categories. Porous tantalum shows promising results in revision arthroplasty with severe acetabular bone loss.

Trabecular Metal Cup without Augments for Acetabular Revision in Case of Extensive Bone Loss and Low Bone-Prosthesis Contact

Current evidences in revision hip arthroplasty suggest to treat severe acetabular bone loss with dedicated implants, such as anti-protrusio cages, stemmed cups, modular systems supplied with iliac flanges and obturatory hook. However recent literature is reporting satisfactory outcomes with simple elliptical Trabecular Metal cups. Purpose of the study was to evaluate mid-term results of such a surgical procedure. All hip revisions performed from 2008 to 2009 with implantation of a TMT multi-hole acetabular cup without augmentations were retrospectively reviewed. The cases with low-degree acetabular bone loss (stage I and II according to GIR classification), with surgical report poorly describing the bone defect, with inadequate pre- and post-operative x-rays were ruled out. Twenty-five cases were identified, but four were lost to follow-up. The twenty-one patients were 71 year-old on average (from 60 to 82), with stage IV bone loss in 6 cases and stage III bone loss in 15 cases. Mean interval from surgery to evaluation was 20.9 months (from 13 to 30). The evaluation included bone-prosthesis contact estimation, component position, survivorship, complications, final Harris Hip Score, presence of periprosthetic radiolucencies. Host bone-prosthesis contact was estimated to be about 35%. Only three implant were subsequently reoperated (for infection, early migration, recurrent dislocation). The HHS among non-reoperated 18 patients was 81.96 on average (from 63.44 to 95.82). Six cases showed thin radiolucencies in one of the three Charnley zones, while three cases showed radiolucencies in two. None of these images was evolutive, thus they were not considered signs of loosening. The mid-term results of this series confirm the hypothesis that a porous tantalum acetabular cup is an effective option to deal with difficult acetabular revisions. Although no extra-acetabular fixation device is available, the very high surface friction guaranteed by the material and the supplemental stability provided by trans-acetabular screws seem to be sufficient to allow satisfactory reimplantation even in severely damaged pelves.

Does a Cemented Cage Improve Revision THA for Severe Acetabular Defects?

BackgroundEvidence suggests a growing incidence of revision total hip arthroplasty (THA) including a subset with large acetabular defects. Revision THA for severe acetabular bone loss is associated with a relatively high rate of mechanical failure.Questions/purposesWe questioned whether cementing a cage to the reconstructed acetabular defect and pelvis would improve the rate of mechanical failure for patients with Type 3 defects (Paprosky et al.) with and without pelvic discontinuity in comparison to historical controls.MethodsWe retrospectively collected data on 33 patients who underwent 35 revision THAs using an acetabular reconstruction cage cemented to morselized allograft and either structural allograft or trabecular metal augmentation for Type 3 defects in the presence (n = 13) and absence (n = 22) of pelvic discontinuity at a mean followup of 59 months (range, 24–92 months). The primary outcome was mechanical failure, defined as revision of the acetabular reconstruction for aseptic loosening.ResultsRevision surgery for mechanical failure occurred in four of the 13 patients with pelvic discontinuity and two of the 22 patients without discontinuity. Radiographic loosening occurred in one patient with and one patient without pelvic discontinuity. Seven of the 35 revisions were subsequently revised for deep infection all in patients who were immunocompromised.ConclusionsCementing the cage to the pelvis can offer an advantage for treating severe acetabular defects. Trabecular metal augmentation appears to provide better initial mechanical stability than a structural allograft, but successful allograft reconstruction may restore bone stock.Level of EvidenceLevel IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Trabecular Metal buttress augment and the Trabecular Metal cup-cage construct in revision hip arthroplasty for severe acetabular bone loss and pelvic discontinuity

Large acetabular defects can be reconstructed using a tantalum Trabecular Metal acetabular component with Trabecular Metal buttress augments. We asked if these reconstructions survived at short-term follow-up. Of 35 patients undergoing acetabular reconstruction with a Trabecular Metal acetabular revision system from 2006, 19 acetabular revisions associated with major bone loss in which we reconstructed the acetabulum with buttress tantalum augments or cup-cage construct combined with a Trabecular Metal shell, were available for evaluation. Mean follow-up was 26 months (range 18-43 months). Mean patient age was 63 years, and 12 patients were women. All defects were classified according to Paprosky and Saleh classifications; there were 13 type IIIA and 6 type IIIB acetabular defects. Five chronic pelvic discontinuities were preoperatively or intraoperatively assessed (Saleh type 5) and a cup-cage construction was employed. No mechanical failure has occurred in any hip, and all patients have radiographically stable cups. Radiographic assessment showed an improvement in the position of the rotation centre of the hip, from a vertical position a mean of 3.5 cm (range 1.6-5.5 cm), to 1.4 cm (range 0.5-2.7 cm) postoperatively. The centre of the femoral head was relocated from a mean of 1.4 cm (range, -3 to 2.6 cm) lateral from the vertical at the teardrop to 3 cm (range 0.2-4 cm). Our early results suggest that buttress tantalum augments, with cup-cage construct for severe bone defects, may be an alternative to other treatment options, but a longer follow-up is necessary.

Trabecular Metal buttress augment and the Trabecular Metal cup-cage construct in revision hip arthroplasty for severe acetabular bone loss and pelvic discontinuity

Large acetabular defects can be reconstructed using a tantalum Trabecular Metal acetabular component with Trabecular Metal buttress augments. We asked if these reconstructions survived at short-term follow-up. Of 35 patients undergoing acetabular reconstruction with a Trabecular Metal acetabular revision system from 2006, 19 acetabular revisions associated with major bone loss in which we reconstructed the acetabulum with buttress tantalum augments or cup-cage construct combined with a Trabecular Metal shell, were available for evaluation. Mean follow-up was 26 months (range 18-43 months). Mean patient age was 63 years, and 12 patients were women. All defects were classified according to Paprosky and Saleh classifications; there were 13 type IIIA and 6 type IIIB acetabular defects. Five chronic pelvic discontinuities were preoperatively or intraoperatively assessed (Saleh type 5) and a cup-cage construction was employed. No mechanical failure has occurred in any hip, and all patients have radiographically stable cups. Radiographic assessment showed an improvement in the position of the rotation centre of the hip, from a vertical position a mean of 3.5 cm (range 1.6-5.5 cm), to 1.4 cm (range 0.5-2.7 cm) postoperatively. The centre of the femoral head was relocated from a mean of 1.4 cm (range, -3 to 2.6 cm) lateral from the vertical at the teardrop to 3 cm (range 0.2-4 cm). Our early results suggest that buttress tantalum augments, with cup-cage construct for severe bone defects, may be an alternative to other treatment options, but a longer follow-up is necessary.

Acetabular revision using an anti-protrusion (ilio-ischial) cage and trabecular metal acetabular component for severe acetabular bone loss associated with pelvic discontinuity

Pelvic discontinuity with associated bone loss is a complex challenge in acetabular revision surgery. Reconstruction using ilio-ischial cages combined with trabecular metal acetabular components and morsellised bone (the component-cage technique) is a relatively new method of treatment. We reviewed a consecutive series of 26 cases of acetabular revision reconstructions in 24 patients with pelvic discontinuity who had been treated by the component-cage technique. The mean follow-up was 44.6 months (24 to 68). Failure was defined as migration of a component of > 5 mm. In 23 hips (88.5%) there was no clinical or radiological evidence of loosening at the last follow-up. The mean Harris hip score improved significantly from 46.6 points (29.5 to 68.5) to 76.6 points (55.5 to 92.0) at two years (p < 0.001). In three hips (11.5%) the construct had migrated at one year after operation. The complications included two dislocations, one infection and one partial palsy of the peroneal nerve. Our findings indicate that treatment of pelvic discontinuity using the component-cage construct is a reliable option.

A Review of the Treatment of Pelvic Discontinuity

Pelvic discontinuity is a complex entity with a high surgical complication rate and no standardized treatment to date. Revision hip arthroplasty in cases of massive bone loss remains a difficult and unsolved problem. The goal of the surgeon is to preserve limb function by restoring bone stock and the biomechanics of the hip. In cases of severe acetabular bone loss, biologic fixation is often inadequate, requiring extensive bone grafting and reconstructive cages. Reconstructive cages are the most commonly used devices and are designed to bridge bone defects, protect the bone graft, and reestablish the rotation center of the hip. A major limitation of current cages is that they do not allow for biologic fixation. We review the options for treating patients with massive bone loss and pelvic discontinuity and discuss therapeutic options and the clinical and radiological criteria for success.

Addressing Severe Bone Deficiency: What a Cage Will Not Do

Managing severe acetabular bone loss in total hip arthroplasty revision can be a tremendous challenge. Osteolysis and migration of the acetabular component can lead to large uncontained defects. Traditionally, these deficiencies have been treated with allograft with or without the support of a cage. In severe cases, a majority of the cage support is via allograft instead of host bone. Sometimes, with remodeling and resorption of the allograft, the cage can lose structural support, leading to fatigue and failure. In these situations, trabecular metal has become a viable alternative. Deficiencies of acetabular bone can be independently addressed and reconstructed providing initial stability and, we believe, long-term biologic fixation to host bone.

Treatment of Severe Acetabular Deficiency Using Modular Trabecular Metal Components

Acetabular fixation in patients requiring revision total hip arthroplasty who have a nonsupportive superior dome and proximal migration of the acetabular component (Paprosky type IIIA defect) or who have a nonsupportive anterior and posterior column with proximal/medial migration of the acetabular component (Paprosky type IIIB defect) cannot be achieved reliably with the use of a hemispherical porous-coated component alone. Pelvic discontinuity is frequently encountered in patients with severe acetabular bone loss.

HIGH PLACEMENT OF NONCEMENTED ACETABULAR COMPONENTS IN REVISION TOTAL HIP ARTHROPLASTY

We previously reported the average ten-year results associated with the use of porous-coated noncemented acetabular shells that were placed at a high hip center at the time of revision total hip arthroplasty in thirty-four patients (thirty-six hips) with severe acetabular bone loss. We now report the average 16.8-year results for twenty-one patients (twenty-three hips). Of the original cohort of forty-four patients (forty-six hips), thirty-nine patients (forty-one hips; 89%) retained the shell. Two shells (4.3%) were revised because of aseptic loosening, and three (6.5%) were revised because of infection. Six femoral components were revised because of femoral osteolysis, and seven were revised because of aseptic loosening without osteolysis. On the basis of our results after an average duration of follow-up of 16.8 years, we believe that the placement of an uncemented acetabular component at a high hip center continues to be an excellent technique for revision total hip arthroplasty in selected patients with severe acetabular bone loss. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

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We previously reported the average ten-year results associated with the use of porous-coated noncemented acetabular shells that were placed at a high hip center at the time of revision total hip arthroplasty in thirty-four patients (thirty-six hips) with severe acetabular bone loss. We now report the average 16.8-year results for twenty-one patients (twenty-three hips). Of the original cohort of forty-four patients (forty-six hips), thirty-nine patients (forty-one hips; 89%) retained the shell. Two shells (4.3%) were revised because of aseptic loosening, and three (6.5%) were revised because of infection. Six femoral components were revised because of femoral osteolysis, and seven were revised because of aseptic loosening without osteolysis. On the basis of our results after an average duration of follow-up of 16.8 years, we believe that the placement of an uncemented acetabular component at a high hip center continues to be an excellent technique for revision total hip arthroplasty in selected patients with severe acetabular bone loss.

The Treatment of Acetabular Bone Defects with an Associated Pelvic Discontinuity

Pelvic discontinuity is encountered frequently during acetabular revision in patients with severe acetabular bone loss. Prompt recognition of the discontinuity and appropriate intraoperative treatment are essential for a successful clinical outcome. The treatment of the discontinuity is dependent on the remaining host bone, the potential for healing of the discontinuity, and the potential for biologic ingrowth of acetabular components. If healing potential of the discontinuity exists, the discontinuity should be treated in compression with a posterior column plate and structural allograft or with the use of trabecular metal acting as an internal plate. If healing potential for the discontinuity does not exist, the discontinuity should be bridged and treated in distraction with an acetabular transplant supported with a cage, a trabecular metal component with trabecular metal augmentation, or with the use of a custom triflange implant. Therapeutic study, Level III-1 (case-control study). See the Guidelines for Authors for a complete description of levels of evidence.

Biphasic phospho-calcium ceramics used as bone substitutes are efficient in the management of severe acetabular bone loss in revision total hip arthroplasties.

Management of bone loss in revision total hip replacement is a challenge. To eliminate any immunological or infectious problem and so to try to improve the long term results obtained with allografts the authors used synthetic ceramics as bone substitutes. Thirty-two hips with a mean follow-up of about 5.5 years (from 3 years to 8 years) were reviewed for this study. The bone defect was classified according to American Academy for Orthopaedic Surgery classification. Two ceramics, one in granules for cavities filling, another in different forms to reconstruct segmental deficiencies, were used; according to the local bone conditions and the age of the patient no cemented jumbo cups or screwed reconstruction rings with a hook and with a polyethylene cup were implanted. Clinical results were assessed according to Postel and Merle d’Aubigne scale. No specific complications were noted. Other complications as dislocations or infections were on a level with other series in this surgery. Radiological assessment affirmed a good integration without any border in all the cases except in one infection. No secondary displacement occurred except in one case after a fall with an acetabular fracture. A progressive invasion of the ceramics by bone can be seen on the X-ray in all cases. Although 5.5 years of average retreat remain a short follow-up in orthopaedic surgery, the outcomes without specific complications are satisfactory and allow one to go with this materials in total hip revision surgery.

The Treatment of Pelvic Discontinuity During Acetabular Revision

Pelvic discontinuity is frequently encountered during acetabular revision in patients with severe acetabular bone loss. Prompt recognition of the discontinuity and appropriate intraoperative management are essential for a successful clinical outcome. The treatment of the discontinuity is dependent upon the remaining host bone, the potential for healing of the discontinuity, and the potential for biologic ingrowth of acetabular components. If healing potential of the discontinuity exists, the discontinuity should be treated in compression with a posterior column plate and structural allograft or with the use of trabecular metal acting as an internal plate. If healing potential for the discontinuity does not exist, the discontinuity can be bridged and treated in distraction with either an acetabular transplant supported with a cage or with the use of a custom Triflange implant. However, the poor clinical results observed with either of these treatment modalities for a type IIIB defect with an associated pelvic discontinuity have prompted the senior author to explore the use of a trabecular metal acetabular component with 1 or 2 augments in the majority of his current type IIIB cases. The long-term clinical results of this treatment remain unknown.

Modular Porous Metal Augments for Treatment of Severe Acetabular Bone Loss during Revision Hip Arthroplasty

Modular acetabular augments were implanted in 16 patients (16 hips) for support of an uncemented hemispheric acetabular component during revision acetabular reconstruction. Based on the classification of Paprosky, acetabular bone defects were classified as 2A in one hip, 2B in three hips, 2C in one hip, 3A in five hips, and 3B in six hips. Preoperatively, the prosthetic femoral head centers were located at a mean horizontal distance of 18.6 mm (range, -3-46 mm), and a mean vertical distance of 27.6 mm (range, -16-52 mm) from the approximate femoral head center. Postoperatively, the prosthetic femoral head centers were located at a mean horizontal distance of 10.4 mm (range, 1-25 mm), and a mean vertical distance of 7.4 mm (range, -15-25 mm). At final followup, no implant had evidence of migration or loosening. At early clinical followup, this modular acetabular augment system seems helpful in acetabular reconstructions that cannot be treated with an uncemented hemispheric cup that would have required other forms of treatment such as structural allografts, acetabular cages, bilobed acetabular components, or custom acetabular components. Longer term followup is required to determine whether there are untoward effects of using a modular acetabular reconstructive system.