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Polyethylene Exchange in a Second-Generation Cementless Acetabular Component
The Journal of Arthroplasty Vol. 24 No. 6 Suppl. 1 2009
Polyethylene Exchange in a Second-Generation Cementless Acetabular Component Michael J. Archibeck, MD, Daniel W. Junick, MD, Tamara Cummins, RT(R)(ARRT), Joshua Carothers, MD, and Richard E. White Jr, MD
Abstract: Some have suggested that isolated polyethylene exchange in a well-fixed Harris-Galante II acetabular component (Zimmer, Warsaw, Ind) necessitates cementing the liner or complete revision because the locking mechanism is suboptimal. We reviewed 29 hip revisions during which the polyethylene was exchanged using the native locking mechanism. Mean follow-up was 5.1 years (2-13 years). Of the 29 patients, one had a disengagement of the revision polyethylene at 2.5 years. At the time of this patient's original revision, one of the tines was fractured, but a direct exchange was performed. There were 4 other revisions (one for loosening and 3 for instability). There were no other complications attributable to the direct polyethylene exchange and no further reoperations. This series suggests that polyethylene exchange with the Harris-Galante II prosthesis can be performed safely using the native locking mechanism in the absence of fractured tines. Keywords: polyethylene, Harris-Galante, cementless acetabular component. © 2009 Published by Elsevier Inc.
ethylene exchange and revision [1-5]. Several authors have also reported cases of polyethylene disengagement with these designs often associated with wear and polyethylene fatigue [6-10]. Because these acetabular components were one of the most commonly implanted devices in the 1980s and 1990s (an estimated 230 000 HGP-I and 270 000 HGP-II worldwide [Zimmer]), there are a large number of patients with polyethylene wear requiring revision at this time. The decision to retain the component and simply exchange the polyethylene, cement a liner into the shell, or revise the entire component can be a difficult one. Generally, if the shell is well fixed and positioned, it is preferable to leave it in situ. Polyethylene exchange can be performed using the available locking mechanism or via cementation of a polyethylene liner into the metallic shell. The purpose of this study was to review the minimum 2-year results of polyethylene exchange using the native locking mechanism in the HGP-II acetabular design.
Cementless acetabular components were introduced to address the perceived high loosening rate of cemented acetabular components. First-generation designs included a variety of ingrowth surfaces and supplemental fixation techniques. The Harris-Galante Porous I (HGP-I) acetabular component was introduced in 1984 (Zimmer, Warsaw, Ind). This design included a hemispheric titanium shell with titanium fiber metal ingrowth surface. Three pairs of tines were used as the polyethylene locking mechanism in all sizes. The Harris-Galante Porous II (HGP-II) component was introduced in 1988 (Zimmer). This device retained the shape and ingrowth surfaces but added additional pairs of tines to the locking mechanism (4-6 pairs depending on the size) and implemented larger (6.5 mm) screws for supplemental fixation (Fig. 1). In both designs, the polyethylene was secured to the metallic shell with several pairs of tines that were slightly bent inward to snap into a circumferential slot in the polyethylene. Although fixation of the metallic shell has been reported to be excellent, polyethylene wear and osteolysis were problems that have necessitated poly-
Materials and Methods The senior author implanted a total of 834 HGP-II acetabular components for primary hip arthroplasty between 1984 and 1988. Between March of 1989 and June of 2004, we performed a total of 29 consecutive hip revisions in 29 patients at a single institution during which the acetabular metallic shell was retained. In all cases, the polyethylene was exchanged using the native locking mechanism. There were 18 females and 11 males with a mean age of 60 years (range, 36-86 years). No patients were lost to follow-up. The reason for revision
From the New Mexico Center for Joint Replacement Surgery, New Mexico Orthopaedics, Albuquerque, New Mexico. Submitted December 15, 2008; accepted May 5, 2009. Michael J. Archibeck, MD has been on the Zimmer speakers bureau and has served as a paid consultant for implant and instrument evaluation. Richard E. White, Jr. MD has received royalties from Zimmer and has functioned as a paid consultant. Reprint requests: Michael J. Archibeck, MD, New Mexico Orthopaedics, 201 Cedar SE, Suite 6600, Albuquerque, NM 87106. © 2009 Published by Elsevier Inc. 0883-5403/09/2406-0015$36.00/0 doi:10.1016/j.arth.2009.05.004
69
70 The Journal of Arthroplasty Vol. 24 No. 6 Suppl. 1 September 2009 inch curved osteotome inserted into the polyethylene rim. The polyethylene liner was gently levered out with care being taken to avoid damage to the metallic rim or tines. The rim was inspected to confirm the absence of any damaged or broken tines. The fixation of the component was confirmed with gentle peripheral impaction. Screws were generally left in place, if present. A trial liner was typically inserted for trial reductions. Once the appropriate liner was identified, the tines were gently bent inward approximately 1 to 2 mm using a large needle driver. The new polyethylene was then inserted with a snap fit of the tines into the groove. If possible, the femoral revision included the use of the largest head possible while maintaining at least 4 to 6 mm of polyethylene thickness. This generally meant the use of a 28- or 32-mm head.
Results Fig. 1. This is a photograph of the HGP-II acetabular component.
included 12 for femoral loosening (one of which was associated with a periprosthetic fracture), 8 for polyethylene wear (2 of which had polyethylene dissociation), 7 for recurrent instability, and 2 for sepsis (components retained). These patients were followed clinically and radiographically for the duration of their follow-up. The technique of polyethylene exchange generally included a posterior approach with exposure of the periphery of the acetabular metallic shell in its entirety. The old polyethylene liner was removed using a quarter
Fig. 2. This radiograph demonstrates the preoperative radiograph of the case with subsequent polyethylene disengagement. Notice the asymmetric polyethylene wear and osteolysis.
The mean age at revision was 60 years (36-86 years). Mean follow-up was 5.4 years (2-13 years). Of the 29 patients, one patient died before 2-year follow-up, and no additional patients were lost, leaving 28 for evaluation. Of these 28 patients, only one had less than 2-year radiographic follow-up but was contacted by phone and refused to return for radiographs. He, however, indicated no subsequent surgery or difficulties. The mean Hip Society Score improved from a mean of 69.5 (range, 31-75) preoperatively to 75.9 (range, 56-94) at last follow-up. There were 5 reoperations. One was revised for osteolysis and acetabular loosening, 3 were revised for recurrent instability (one poly exchange and 2 to a constrained component), and one was revised for polyethylene disengagement at 2.5 years postrevision. The case of subsequent acetabular loosening was reviewed, and there was no evidence of radiographic loosening before the index revision. The original indica-
Fig. 3. This radiograph demonstrates the appearance of the case 2.5 years postreduction with evidence of fractured tines and polyethylene disengagement.
Polyethylene Exchange in a Cementless Acetabular Component Archibeck et al
Fig. 4. This radiograph was obtained after revision of the entire component.
tion for revision in the 3 cases with recurrent instability included one femoral revision with polyethylene exchange and 2 isolated head and polyethylene exchanges. There were no other complications attributable to the direct polyethylene exchange and no further reoperations. Radiographic review of the patients not requiring additional revision demonstrated no cases of acetabular loosening, polyethylene disengagement, or progressive radiolucencies. The case of the polyethylene disengagement after direct polyethylene exchange was reviewed. The reason for the initial revision was polyethylene wear and osteolysis (Fig. 2). The surgeon indicated in the operative note that the screws were removed and the fixation was secure. A single tine was identified as fractured. This particular size component possessed 5 pairs of tines. The remaining tines were found to be intact, and a direct polyethylene exchange was performed using the technique described above. At 30 months postrevision, the patient complained of the sudden onset of hip pain and crepitation. Radiographs at that time (Fig. 3) demonstrated polyethylene disengagement and evidence of 2 fractured tines. The patient then underwent a second revision, during which the entire acetabular component was revised (Fig. 4). The patient has done well since that time.
Discussion The Harris-Galante II acetabular component was a frequently used design during its service period (estimated 270 000 implanted worldwide) with excellent clinical results in both the primary and revision settings [1-5]. Revisions during which a well-fixed and positioned acetabular component is present are a common scenario with this particular design. We reviewed 29 consecutive hip revisions performed for a variety of reasons during which the acetabular metallic shell was
71
retained and the polyethylene was exchanged. In all cases, the native locking mechanism was used. Of the 29 patients, one had a disengagement of the revision polyethylene at 2.5 years. At the time of this patient's original revision, one of the tines was found to be fractured, but a direct exchange was performed. There were 5 reoperations. One was revised for osteolysis and acetabular loosening, 3 were revised for recurrent instability (one poly exchange and 2 to a constrained component), and one was revised for polyethylene disengagement at 2.5 years postrevision. There were no other complications attributable to the direct polyethylene exchange and no further reoperations. This series suggests that polyethylene exchange with the Harris-Galante II prosthesis can be performed safely using the native locking mechanism in the absence of fractured tines. The Harris-Galante II has demonstrated excellent survivorship in a variety of patient populations [1-5]. The limiting issues with this and similar designs remain polyethylene wear and related osteolysis [1]. Several authors have reported cases of polyethylene disengagement associated with such wear. Gonzales Della Valle et al [6] reported on 18 cases of polyethylene disengagement from Harris-Galante components at a mean of 7 years postimplantation and hypothesized that, as the polyethylene wears, the strain on this primitive locking mechanism results in fatigue injury to the tines and, thus, disengagement. Werle et al [10] reported on 7 cases of polyethylene disengagement in Harris-Galante components and generally revised the entire component when this occurred. Saito et al [9] published 5 cases of polyethylene disengagement (of 76 implanted) from Harris-Galante I components in which they cemented new liners into all 7 cases that have functioned well for a mean 6.4 years of follow-up. Peters and Sullivan [8] investigated 2 cases of locking mechanism failure with fractured tines presenting as recurrent dislocation. They revised the entire component in one case and exchanged the polyethylene in the other. They concluded that “appropriate treatment for locking mechanism failure with a well-fixed acetabular component depends on many factors, and further long-term data are needed.” Lachiewicz and Soileau [7] reviewed 400 HGP-I components (mean, 10-year follow-up) and 78 HGP-II components (mean, 8-year follow-up) and identified only one-liner disengagement (0.2%). Thirty-five hips had undergone revision with liner exchange using the native locking mechanism with no subsequent liner disengagements at 5.1 years of follow-up. In summary, with the presence of intact tines, direct polyethylene exchange using the native locking mechanism appears to be an effective method by which the bearing surface can be exchanged. Based on the findings of this study and that of Lachiewicz, we continue to perform direct polyethylene exchange with a highly cross-linked liner as long as there are no fractured tines
72 The Journal of Arthroplasty Vol. 24 No. 6 Suppl. 1 September 2009 present at the time of revision and the shell is well fixed and positioned.
References 1. Archibeck MJ, Berger RA, Jacobs JJ, et al. Secondgeneration cementless total hip arthroplasty. Eight to eleven-year results. J Bone Joint Surg Am 2001;83A:1666. 2. Clohisy JC, Harris WH. The Harris-Galante porous-coated acetabular component with screw fixation. An average ten-year follow-up study. J Bone Joint Surg Am 1999; 81:66. 3. Della Valle CJ, Berger RA, Shott S, et al. Primary total hip arthroplasty with a porous-coated acetabular component. A concise follow-up of a previous report. J Bone Joint Surg Am 2004;86-A:1217. 4. Della Valle CJ, Shuaipaj T, Berger RA, et al. Revision of the acetabular component without cement after total hip arthroplasty. A concise follow-up, at fifteen to nineteen years, of a previous report. J Bone Joint Surg Am 2005; 87:1795.
5. Jamali AA, Dungy DS, Mark A, et al. Isolated acetabular revision with use of the Harris-Galante Cementless Component. Study with intermediate-term follow-up. J Bone Joint Surg Am 2004;86-A:1690. 6. Gonzalez Della Valle A, Ruzo PS, Li S, et al. Dislodgment of polyethylene liners in first and second-generation HarrisGalante acetabular components. A report of eighteen cases. J Bone Joint Surg Am 2001;83-A:553. 7. Lachiewicz PF, Soileau ES. Polyethylene liner exchange of the Harris-Galante porous I and II acetabular components without cement: results and complications. J Arthroplasty 2006;21:992. 8. Peters CL, Sullivan CL. Locking mechanism failure in the Harris-Galante porous acetabular component associated with recurrent hip dislocation. J Arthroplasty 2002;17:507. 9. Saito S, Ryu J, Seki M, et al. Analysis and results of dissociation of the polyethylene liner in the Harris-Galante I acetabular component. J Arthroplasty 2008;23:522. 10. Werle J, Goodman S, Schurman D, et al. Polyethylene liner dissociation in Harris-Galante acetabular components: a report of 7 cases. J Arthroplasty 2002;17:78.
Polyethylene Exchange in a Second-Generation Cementless Acetabular Component Michael J. Archibeck, MD, Daniel W. Junick, MD, Tamara Cummins, RT(R)(ARRT), Joshua Carothers, MD, and Richard E. White Jr, MD
Abstract: Some have suggested that isolated polyethylene exchange in a well-fixed Harris-Galante II acetabular component (Zimmer, Warsaw, Ind) necessitates cementing the liner or complete revision because the locking mechanism is suboptimal. We reviewed 29 hip revisions during which the polyethylene was exchanged using the native locking mechanism. Mean follow-up was 5.1 years (2-13 years). Of the 29 patients, one had a disengagement of the revision polyethylene at 2.5 years. At the time of this patient's original revision, one of the tines was fractured, but a direct exchange was performed. There were 4 other revisions (one for loosening and 3 for instability). There were no other complications attributable to the direct polyethylene exchange and no further reoperations. This series suggests that polyethylene exchange with the Harris-Galante II prosthesis can be performed safely using the native locking mechanism in the absence of fractured tines. Keywords: polyethylene, Harris-Galante, cementless acetabular component. © 2009 Published by Elsevier Inc.
ethylene exchange and revision [1-5]. Several authors have also reported cases of polyethylene disengagement with these designs often associated with wear and polyethylene fatigue [6-10]. Because these acetabular components were one of the most commonly implanted devices in the 1980s and 1990s (an estimated 230 000 HGP-I and 270 000 HGP-II worldwide [Zimmer]), there are a large number of patients with polyethylene wear requiring revision at this time. The decision to retain the component and simply exchange the polyethylene, cement a liner into the shell, or revise the entire component can be a difficult one. Generally, if the shell is well fixed and positioned, it is preferable to leave it in situ. Polyethylene exchange can be performed using the available locking mechanism or via cementation of a polyethylene liner into the metallic shell. The purpose of this study was to review the minimum 2-year results of polyethylene exchange using the native locking mechanism in the HGP-II acetabular design.
Cementless acetabular components were introduced to address the perceived high loosening rate of cemented acetabular components. First-generation designs included a variety of ingrowth surfaces and supplemental fixation techniques. The Harris-Galante Porous I (HGP-I) acetabular component was introduced in 1984 (Zimmer, Warsaw, Ind). This design included a hemispheric titanium shell with titanium fiber metal ingrowth surface. Three pairs of tines were used as the polyethylene locking mechanism in all sizes. The Harris-Galante Porous II (HGP-II) component was introduced in 1988 (Zimmer). This device retained the shape and ingrowth surfaces but added additional pairs of tines to the locking mechanism (4-6 pairs depending on the size) and implemented larger (6.5 mm) screws for supplemental fixation (Fig. 1). In both designs, the polyethylene was secured to the metallic shell with several pairs of tines that were slightly bent inward to snap into a circumferential slot in the polyethylene. Although fixation of the metallic shell has been reported to be excellent, polyethylene wear and osteolysis were problems that have necessitated poly-
Materials and Methods The senior author implanted a total of 834 HGP-II acetabular components for primary hip arthroplasty between 1984 and 1988. Between March of 1989 and June of 2004, we performed a total of 29 consecutive hip revisions in 29 patients at a single institution during which the acetabular metallic shell was retained. In all cases, the polyethylene was exchanged using the native locking mechanism. There were 18 females and 11 males with a mean age of 60 years (range, 36-86 years). No patients were lost to follow-up. The reason for revision
From the New Mexico Center for Joint Replacement Surgery, New Mexico Orthopaedics, Albuquerque, New Mexico. Submitted December 15, 2008; accepted May 5, 2009. Michael J. Archibeck, MD has been on the Zimmer speakers bureau and has served as a paid consultant for implant and instrument evaluation. Richard E. White, Jr. MD has received royalties from Zimmer and has functioned as a paid consultant. Reprint requests: Michael J. Archibeck, MD, New Mexico Orthopaedics, 201 Cedar SE, Suite 6600, Albuquerque, NM 87106. © 2009 Published by Elsevier Inc. 0883-5403/09/2406-0015$36.00/0 doi:10.1016/j.arth.2009.05.004
69
70 The Journal of Arthroplasty Vol. 24 No. 6 Suppl. 1 September 2009 inch curved osteotome inserted into the polyethylene rim. The polyethylene liner was gently levered out with care being taken to avoid damage to the metallic rim or tines. The rim was inspected to confirm the absence of any damaged or broken tines. The fixation of the component was confirmed with gentle peripheral impaction. Screws were generally left in place, if present. A trial liner was typically inserted for trial reductions. Once the appropriate liner was identified, the tines were gently bent inward approximately 1 to 2 mm using a large needle driver. The new polyethylene was then inserted with a snap fit of the tines into the groove. If possible, the femoral revision included the use of the largest head possible while maintaining at least 4 to 6 mm of polyethylene thickness. This generally meant the use of a 28- or 32-mm head.
Results Fig. 1. This is a photograph of the HGP-II acetabular component.
included 12 for femoral loosening (one of which was associated with a periprosthetic fracture), 8 for polyethylene wear (2 of which had polyethylene dissociation), 7 for recurrent instability, and 2 for sepsis (components retained). These patients were followed clinically and radiographically for the duration of their follow-up. The technique of polyethylene exchange generally included a posterior approach with exposure of the periphery of the acetabular metallic shell in its entirety. The old polyethylene liner was removed using a quarter
Fig. 2. This radiograph demonstrates the preoperative radiograph of the case with subsequent polyethylene disengagement. Notice the asymmetric polyethylene wear and osteolysis.
The mean age at revision was 60 years (36-86 years). Mean follow-up was 5.4 years (2-13 years). Of the 29 patients, one patient died before 2-year follow-up, and no additional patients were lost, leaving 28 for evaluation. Of these 28 patients, only one had less than 2-year radiographic follow-up but was contacted by phone and refused to return for radiographs. He, however, indicated no subsequent surgery or difficulties. The mean Hip Society Score improved from a mean of 69.5 (range, 31-75) preoperatively to 75.9 (range, 56-94) at last follow-up. There were 5 reoperations. One was revised for osteolysis and acetabular loosening, 3 were revised for recurrent instability (one poly exchange and 2 to a constrained component), and one was revised for polyethylene disengagement at 2.5 years postrevision. The case of subsequent acetabular loosening was reviewed, and there was no evidence of radiographic loosening before the index revision. The original indica-
Fig. 3. This radiograph demonstrates the appearance of the case 2.5 years postreduction with evidence of fractured tines and polyethylene disengagement.
Polyethylene Exchange in a Cementless Acetabular Component Archibeck et al
Fig. 4. This radiograph was obtained after revision of the entire component.
tion for revision in the 3 cases with recurrent instability included one femoral revision with polyethylene exchange and 2 isolated head and polyethylene exchanges. There were no other complications attributable to the direct polyethylene exchange and no further reoperations. Radiographic review of the patients not requiring additional revision demonstrated no cases of acetabular loosening, polyethylene disengagement, or progressive radiolucencies. The case of the polyethylene disengagement after direct polyethylene exchange was reviewed. The reason for the initial revision was polyethylene wear and osteolysis (Fig. 2). The surgeon indicated in the operative note that the screws were removed and the fixation was secure. A single tine was identified as fractured. This particular size component possessed 5 pairs of tines. The remaining tines were found to be intact, and a direct polyethylene exchange was performed using the technique described above. At 30 months postrevision, the patient complained of the sudden onset of hip pain and crepitation. Radiographs at that time (Fig. 3) demonstrated polyethylene disengagement and evidence of 2 fractured tines. The patient then underwent a second revision, during which the entire acetabular component was revised (Fig. 4). The patient has done well since that time.
Discussion The Harris-Galante II acetabular component was a frequently used design during its service period (estimated 270 000 implanted worldwide) with excellent clinical results in both the primary and revision settings [1-5]. Revisions during which a well-fixed and positioned acetabular component is present are a common scenario with this particular design. We reviewed 29 consecutive hip revisions performed for a variety of reasons during which the acetabular metallic shell was
71
retained and the polyethylene was exchanged. In all cases, the native locking mechanism was used. Of the 29 patients, one had a disengagement of the revision polyethylene at 2.5 years. At the time of this patient's original revision, one of the tines was found to be fractured, but a direct exchange was performed. There were 5 reoperations. One was revised for osteolysis and acetabular loosening, 3 were revised for recurrent instability (one poly exchange and 2 to a constrained component), and one was revised for polyethylene disengagement at 2.5 years postrevision. There were no other complications attributable to the direct polyethylene exchange and no further reoperations. This series suggests that polyethylene exchange with the Harris-Galante II prosthesis can be performed safely using the native locking mechanism in the absence of fractured tines. The Harris-Galante II has demonstrated excellent survivorship in a variety of patient populations [1-5]. The limiting issues with this and similar designs remain polyethylene wear and related osteolysis [1]. Several authors have reported cases of polyethylene disengagement associated with such wear. Gonzales Della Valle et al [6] reported on 18 cases of polyethylene disengagement from Harris-Galante components at a mean of 7 years postimplantation and hypothesized that, as the polyethylene wears, the strain on this primitive locking mechanism results in fatigue injury to the tines and, thus, disengagement. Werle et al [10] reported on 7 cases of polyethylene disengagement in Harris-Galante components and generally revised the entire component when this occurred. Saito et al [9] published 5 cases of polyethylene disengagement (of 76 implanted) from Harris-Galante I components in which they cemented new liners into all 7 cases that have functioned well for a mean 6.4 years of follow-up. Peters and Sullivan [8] investigated 2 cases of locking mechanism failure with fractured tines presenting as recurrent dislocation. They revised the entire component in one case and exchanged the polyethylene in the other. They concluded that “appropriate treatment for locking mechanism failure with a well-fixed acetabular component depends on many factors, and further long-term data are needed.” Lachiewicz and Soileau [7] reviewed 400 HGP-I components (mean, 10-year follow-up) and 78 HGP-II components (mean, 8-year follow-up) and identified only one-liner disengagement (0.2%). Thirty-five hips had undergone revision with liner exchange using the native locking mechanism with no subsequent liner disengagements at 5.1 years of follow-up. In summary, with the presence of intact tines, direct polyethylene exchange using the native locking mechanism appears to be an effective method by which the bearing surface can be exchanged. Based on the findings of this study and that of Lachiewicz, we continue to perform direct polyethylene exchange with a highly cross-linked liner as long as there are no fractured tines
72 The Journal of Arthroplasty Vol. 24 No. 6 Suppl. 1 September 2009 present at the time of revision and the shell is well fixed and positioned.
References 1. Archibeck MJ, Berger RA, Jacobs JJ, et al. Secondgeneration cementless total hip arthroplasty. Eight to eleven-year results. J Bone Joint Surg Am 2001;83A:1666. 2. Clohisy JC, Harris WH. The Harris-Galante porous-coated acetabular component with screw fixation. An average ten-year follow-up study. J Bone Joint Surg Am 1999; 81:66. 3. Della Valle CJ, Berger RA, Shott S, et al. Primary total hip arthroplasty with a porous-coated acetabular component. A concise follow-up of a previous report. J Bone Joint Surg Am 2004;86-A:1217. 4. Della Valle CJ, Shuaipaj T, Berger RA, et al. Revision of the acetabular component without cement after total hip arthroplasty. A concise follow-up, at fifteen to nineteen years, of a previous report. J Bone Joint Surg Am 2005; 87:1795.
5. Jamali AA, Dungy DS, Mark A, et al. Isolated acetabular revision with use of the Harris-Galante Cementless Component. Study with intermediate-term follow-up. J Bone Joint Surg Am 2004;86-A:1690. 6. Gonzalez Della Valle A, Ruzo PS, Li S, et al. Dislodgment of polyethylene liners in first and second-generation HarrisGalante acetabular components. A report of eighteen cases. J Bone Joint Surg Am 2001;83-A:553. 7. Lachiewicz PF, Soileau ES. Polyethylene liner exchange of the Harris-Galante porous I and II acetabular components without cement: results and complications. J Arthroplasty 2006;21:992. 8. Peters CL, Sullivan CL. Locking mechanism failure in the Harris-Galante porous acetabular component associated with recurrent hip dislocation. J Arthroplasty 2002;17:507. 9. Saito S, Ryu J, Seki M, et al. Analysis and results of dissociation of the polyethylene liner in the Harris-Galante I acetabular component. J Arthroplasty 2008;23:522. 10. Werle J, Goodman S, Schurman D, et al. Polyethylene liner dissociation in Harris-Galante acetabular components: a report of 7 cases. J Arthroplasty 2002;17:78.