After obtaining institution review board approval, the clinical notes, hospital records, radiographs, and operative reports for these 37 revision surgeries were retrospectively reviewed.
Of the 35 patients, three (three hips, 8%) were lost to followup. Three additional patients (three hips, 8%) died from causes unrelated to their revision arthroplasty at an average of 28.3 months (13, 19, and 53 months) (Table 1). Although none of these hips were either radiographically loose or required revision, we excluded the two patients who did not survive to minimum followup. Thus, five patients were excluded for inadequate followup, and one deceased patient was included in the cohort. Of the remaining 29 patients, four (13%) were unable to return for radiographic followup but were willing to participate in a telephone survey. At a minimum of 24 months, there were 30 patients (32 hips, 86%) who had clinical followup, and 26 patients (28 hips, 76%) had both clinical and radiographic followup. Mean followup for those not requiring subsequent revision was 53 months (range, 24 to 88 months). Mean patient age at time of surgery was 62.4 years (range, 30.9-86.2 years). There were 15 female (16 hips) and 15 male (16 hips) patients.
We performed 25 revisions (78%) to treat aseptic loosening of the acetabular component with component migration or associated osteolysis. The revised components included 13 loose cemented components (41%) and 12 loose cementless components (38%). There were also seven well fixed cementless components with concerns that directed component revision (22%). The indications for revision of a well-fixed acetabular component included component malposition, a poor implant track record for osseointegration, and massive lysis inaccessible to grafting either through or around the component. Twelve cases (38%) included revision of the femoral component. Multiholed, titanium mesh acetabular implants were utilized for the first 27 cases (84%), with trabecular metal modular revision shells used for the most recent five cases (16%) after these components became available (Zimmer, Inc., Warsaw, IN). Cup size averaged 60.6 mm (range, 52-70 mm) and supplemental fixation was accomplished with a mean of 3.6 screws (range, 2-6).
Surgery was performed by one of the two senior authors (JCC, WJM), using a posterolateral approach for all procedures except a single case that was accomplished with a direct lateral approach. An extended trochanteric osteotomy was utilized for three cases (9%) associated with femoral component revision. Wide surgical exposure is performed to provide adequate visualization to assess the integrity of the anterior and posterior columns, medial wall and superolateral buttress. Well fixed components are removed using a commercially available acetabular component extraction system. After clearing pseudomembrane from the acetabular interface, reamers are placed to size the defect, assess for contact with host bone, and prepare for cup placement. In the presence of large, central deficiencies, cementless fixation is still accepted as long as at least 40-50% of the component can be supported against host bone. Major segmental defects, when present, are assessed for appropriateness of structural grafts or augmentation. This is most important for substantial (> 30%) deficiency of the superolateral buttress, but may also be considered for large superomedial defects. Cancellous allograft, procured from commercially available sources, is obtained from either fresh frozen femoral heads for the largest defects or freeze dried cancellous bone croutons or chips for smaller defects. The graft is delivered into the defect, gently pressed into the defect manually or with a tamp and followed by reverse reaming of the acetabulum. After placement of the acetabular component in appropriate inclination and anteversion, screw fixation is utilized to enhance acetabular component fixation using the maximum number of fixation points that can be attained through the modular acetabular shell. This typically includes fixation points in the ilium and posterior column and, when feasible, into the ischium. Cautious judgment is utilized when anterior column fixation is warranted, as medial component placement frequently leaves minimal thickness of bone in the anterior column for preparation and screw placement. With cases of major osteolysis, periacetabular bone deficiency may limit the number of fixation points that can be attained. After acetabular component placement, stability of fixation against the host bone is then assessed, an acetabular insert is placed, and trial reduction of the hip is performed in routine fashion. Patients are kept on toe-touch weight bearing for 3 months and hip abduction braces are used for 8 weeks.
Patients were seen after surgery at 6-week, 3-month, 6-month, and 1-year intervals. After the first year, patients are recommended to followup annually until 5 years after their surgery and are scheduled for a 10-year followup appointment if there are no clinical or radiographic concerns identified. Patients are seen intermittently at other intervals if they express symptoms or concerns. Anteroposterior (AP) pelvis, AP hip, and crosstable lateral radiographs are routinely performed at each scheduled appointment. Harris Hip Scores  are assessed prior to surgery and again at 3-month, 6-month, 1-year, 2-year, 5-year, and 10-year intervals when patients return for followup. These are entered into an institutional arthroplasty registry database.
Harris Hip Scores were obtained from the registry database. Clinical notes and radiographs were obtained and reviewed for evidence of perioperative complications including: infection, instability, nerve injury, vascular injury, heterotopic ossification, periprosthetic fracture, or any other complication related to the surgical procedure. Complications were defined as major if further surgery or a decline of more than 10 points in the Harris Hip Score resulted from the complication. Other complications were described as minor.
Radiographs were evaluated by an orthopaedic surgery resident (ESP) not involved in the care of the patients and by one of the treating surgeons (JCC), with consensus attained for reporting of all measurements. Vertical, horizontal, or angular component migration was assessed from immediate postoperative and most recent followup radiographs. Horizontal component position was measured relative to a vertical line drawn from the edge of the teardrop and vertical component position was measured by the perpendicular distance of the cup center from the interteardrop line (Fig. 5) [9, 36]. Component migration was defined using criteria as established by Hendricks and Harris : either a change of 4 mm or greater horizontally or vertically, or an angular change of the acetabular component of greater than 5°. Acetabular abduction was defined by the angle made between the interteardrop line and a line drawn tangential to the acetabular component. Previous validating reports of plain radiographic analysis for assessing component migration found good interobserver reliability (k = 0.52-0.63  and 0.76 ) and excellent intraobserver reliability (k = 0.89) .
Preoperative osteolytic lesion size was determined from anteroposterior (AP) and crosstable or frog-leg lateral radiographs. The largest diameter in both vertical and horizontal axes were utilized to calculate area from the equation for an ellipse (Pi * X/2 * Y/2). Osteolytic defects were classified utilizing AAOS .
Bone graft incorporation was classified using the system described by Benson et al. . The first author (ESP) reviewed all cases with the senior author (JCC) and consensus was reached on graft incorporation. Grade 0 incorporation is identified by an absence of trabecular pattern and no change in the defect appearance between preoperative and postoperative radiographs. Grade 1 incorporation is defined by the presence of either a blurred lytic border or the presence of a trabecular pattern distinct from the appearance of the surrounding bone. Grade 2 graft incorporation is denoted by a trabecular bone pattern continuous with the surrounding bone and absence of a border between the defect and surrounding bone.
Heterotopic ossification was assessed using the classification of Brooker et al. . Overall failure was defined by reoperation for acetabular revision. Radiographic loosening was defined by component migration.
Thirty-two hips were available for followup at a minimum of 24 months or until failure. Average preoperative defect size was 12.8 cm2 (range, 4.7-49.5 cm2). Twenty-nine revisions (91%) were performed for AAOS Type III defects, with both cavitary and segmental deficiencies, and the remaining three (9%) addressed large, but contained, cavitary (AAOS Type II) defects. Mean Harris Hip Score improved from 52.6 (range, 17.7-90.7) to 87.3 (range, 25.3-100) after surgery. Twenty-one patients (23 hips, 82%) had a Harris Hip Score between 81 and 100, correlating with a good or excellent outcome, and four patients (14%) had a score less than 70. Only two patients (7%) had a decrease in their Harris Hip Score (Table 2). Twenty-nine of 32 hips (91%) were in place and functioning well at an average followup of 53 months (Table 2). Three hips (9%) that required rerevision were initially revised for aseptic loosening of a cementless acetabular component (Fig. 5). The average preoperative age of patients who required rerevision surgery was 58.2 years (range, 47.6-77.7 years). Two of the three failures were titanium mesh cups fixed with two and five screws, respectively. One trabecular metal cup augmented with two screws failed. All three failures occurred in hips with previous AAOS III defects. The failures occurred at 12, 22, and 132 months. The cup with the longest interval to followup was a titanium mesh cup fixed with two screws. Migration greater than 4 mm was seen in three of the 28 hips (10.7%) that had adequate radiographic followup and had not been revised. Although these implants were considered radiographically loose, Harris Hip Scores improved an average of 49.6 points to a mean of 91.0 points (range, 82.5-97.7). All three of these hips were revisions of AAOS type III defects, and the cup sizes were 52, 68 and 70. No hips had a change in cup abduction angle greater than 5°. Both patients had well-fixed implants radiographically.
Radiographic evaluation showed some element of graft integration in 25 of the 28 hips with adequate radiographic followup (89%). Grade II incorporation was seen in 17 hips (68%), Grade I in seven hips (28%), and Grade 0 in one hip (one patient) (4%). Of the three hips requiring subsequent revision, two hips had Grade II incorporation prior to reoperation and one had Grade 0 incorporation. Intraoperative findings at the time of rerevision for one case with Grade II radiographic incorporation revealed that bone graft had incorporated fully in certain areas, with remaining or new osteolytic defects present in other areas. One rerevision was performed at another institution and the intraoperative appearance of consolidation is not known.
In the 37 index procedures, there were five major (14%) and four minor (11%) complications (Table 3). Major complications included two dislocations, one infection treated with liner exchange and IV antibiotics, one hematoma requiring surgical débridement, and one intraoperative periprosthetic femur fracture that healed uneventfully using a cortical strut graft and cable fixation. All were treated successfully without long-term morbidity. The four minor complications included three cases of Brooker Grade 3 heterotopic ossification (HO) and one postoperative hematoma that resolved without surgical intervention. HO was noted in four other hips (4 patients), two with Grade 2, and two with Grade I HO. None of these patients required additional surgery. There were no cases of nerve palsy, vascular injury, or deep venous thrombosis in the treatment group. Two of 30 patients (2 hips) with clinical followup sustained a single postoperative hip dislocation (7%), but did not require revision surgery.
Periprosthetic osteolysis develops as a biological response to particulate wear debris [20, 28, 31]. Access of particulate debris to the interface around loose cemented and cementless acetabular components may either contribute to the development of focal osteolytic lesions or may result in substantial bone loss as loose components migrate proximally into the pelvis [18, 21, 39]. Expansile focal osteolytic lesions may develop in association with well-fixed cementless components. While component retention may be an option for implants with a good track record for osseointegration and a favorable locking mechanism, component revision is frequently necessary . Regardless of pathogenesis, major pelvic osteolytic deficiencies challenge revision initial implant stability and long-term construct durability. Although several techniques have been reported, including some that suggest successful management of major defects with reconstruction cages [33, 34, 37], other authors have reported poor clinical performance of these constructs [2, 44]. While cementless fixation in acetabular revision is reported to have 97% long-term survivorship [8, 32] associated with acetabular bone loss, the literature contains limited reporting on the use of cementless implants exclusively for the most major bone deficiencies (AAOS III; Paprosky 2B through 3B). We report on the use of focal impaction grafting and cementless acetabular revision for major periacetabular osteolytic defects (Table 4).
Our study has several limitations. First, a sizeable number of patients eligible for consideration in this study were either lost to followup (9%) or did not return for radiographic assessment (13%). When considering best and worst case scenarios for these patients, implant survivorship is between 84 and 92% with revision as an endpoint, and between 73 to 84% when including any radiographic signs of loosening. However, the rate of patients lost to followup is comparable with other studies reporting on patients with severe pelvic defects [35, 47]. Second, although we are reporting on patients with similar acetabular deficiencies previously reported with other techniques, we are not able to adequately compare patient demographics to those other studies. While our mean clinical scores are higher, this may be reflective of the overall physical health of our patients, and not directly to the surgical technique utilized. Third, since the average followup was less than 5 years, long-term durability may not necessarily be extrapolated from our results. Fourth, our cohort was not large enough to statistically evaluate the reasons or risk factors for failure. While we have noted that only two screws were utilized to augment cup fixation in two of the three failures, a third failed component was augmented with five screws. The small sample size does not allow us to differentiate patient factors, bone deficiency, or screw augmentation as the most important factors in component failure in this series. While these cases lack statistical power to determine an ideal number of screws to utilize, we recommend use of at least three screws and attempt to add fixation in the ischium when possible. The quality of press fit of the revision component, either at the rim, between the columns, or throughout the acetabular bed, may influence the minimum number of screws the surgeon is willing to accept. Fourth, our radiographic measurements were made using plain radiographs which may underestimate the preoperative size of defects and overestimate the degree of graft incorporation. Mall et al. noted only 47% of graft fill and 36% graft healing in acetabular osteolytic defects following complete component revision using postoperative CT scan analysis . This is much lower than previously reported rates of 90-100% using plain radiographs for analysis [26, 40]. Other forms of imaging may provide more accurate measurement of bone graft incorporation and component position to assess for migration. Finally, we had only one observer for the radiographic findings. We did not determine and do not know the interobserver variability of assessing bone graft incorporation radiographically.
In this study, mean Harris Hip Score (HHS) improved by from 53 to 87 points and only one patient with a treated AAOS Grade III defect had a substantial decrease in HHS (by 13 points).
The mean clinical score that we report is higher than what has been reported in the literature for high hip center (81 points), cementless acetabular revision (82 points), jumbo acetabular components (79 points), highly porous cementless components (76 points), and reconstruction cages (70 points) (Table 4).
We report a component survivorship of 91% at a mean of 53 months, with an additional 10.7% of potentially loose components unrevised. Chen et al. noted 24% failure at a mean of 41 months with bilobed acetabular components . Dearborn and Harris noted a 10% conversion from a high hip center to a resection arthroplasty . Della Valle et al. noted 97% survivorship of cemented components with loosening as an endpoint, but noted 20/87 surviving patients (23%) requiring a revision for all reasons . Gerber et al. noted seven revised or loose components (14%) with roof reinforcement rings at a mean of 6 years . Schlegel et al. noted an 18% rerevision rate with an additional 2% radiographic or clinical failure rate at 8 years using reconstruction cages . Regis and Pieringer have reported survivorship of 87.5 and 93.4%, respectively, but acknowledge a substantial number of additional cases that are radiographically loose [33, 34].
Our study identified complete radiographic bone graft incorporation for 68% of the cases. However, our limited intraoperative assessment of bone graft incorporation on rerevision cases suggested that radiographs may overestimate the actual amount of bone incorporation. There are few studies that have specifically focused on bone graft incorporation (Table 5). McNamara et al. noted 60% of cases had graft incorporation utilizing a mixture of allograft and synthetic osteoconductive material . Mehendale et al. suggested that complete radiographic incorporation was only present with 40% of patients treated with irradiated bone . Mall et al. have recently reported a 30% average defect fill and 24% average bone healing rate using CT scans for evaluation, with lower graft incorporation rates among patients treated with impaction grafting behind retained acetabular components than during cases where component revision had been accomplished .
There were five major complications (13.5%) and four minor complications (10.8%), with an overall rate of 24.3%. While a majority of reports have not cited complication rates, the range of reported complications within these groups ranged from 11-24.7%. Gerber et al. reported a 16% complication rate . DellaValle et al. noted a 12% revision rate for infection or dislocation . Van Kleunen et al. noted a 24% complication rate at a mean of 45 months .
Cementless acetabular fixation and bone grafting result in improvement in mean Harris Hip Scores and greater than 90% implant survivorship at midterm followup. The results in this study fare well in comparison with other techniques that have been described to manage similar major periacetabular bone loss. Attention should be given to the restoration of acetabular bone stock and the achievement of stable initial fixation of the acetabular component against host bone. Morselized bone graft can accomplish restoration of bone in the acetabulum, but is not sufficient in itself to guarantee clinical success. Multiple screws should be used to enhance the initial stability of the implant. Future studies should provide long-term followup of the use of highly porous cementless fixation implants, and to identify effective strategies to evaluate bone graft incorporation and to establish criteria for both acetabular component loosening and failure.
1. Benson, ER., Christensen, CP., Monesmith, EA., Gomes, SL. and Bierbaum, BE. Particulate bone grafting of osteolytic femoral lesions around stable cementless stems. Clin Orthop Relat Res.
2000; 381: 58-67. 10.1097/00003086-200012000-00007
2. Boscainos, PJ., Kellett, CF., Maury, AC., Backstein, D. and Gross, AE. Management of periacetabular bone loss in revision hip arthroplasty. Clin Orthop Relat Res.
2007; 465: 159-165.
3. Chen, WM., Engh, CA, Jr, Hopper, RH, Jr, McAuley, JP. and Engh, CA. Acetabular revision with use of a bilobed component inserted without cement in patients who have acetabular bone-stock deficiency. J Bone Joint Surg Am.
2000; 82: 197-206.
4. Chiang, PP., Burke, DW., Freiberg, AA. and Rubash, HE. Osteolysis of the pelvis: evaluation and treatment. Clin Orthop Relat Res.
2003; 417: 164-174.
5. Comba, F., Buttaro, M., Pusso, R. and Piccaluga, F. Acetabular reconstruction with impacted bone allografts and cemented acetabular components: a 2- to 13-year follow-up study of 142 aseptic revisions. J Bone Joint Surg Br.
2006; 88: 865-869. 10.1302/0301-620X.88B7.17227
6. D’Antonio, JA., Capello, WN., Borden, LS., Bargar, WL., Bierbaum, BF., Boettcher, WG., Steinberg, ME., Stulberg, SD. and Wedge, JH. Classification and management of acetabular abnormalities in total hip arthroplasty. Clin Orthop Relat Res.
1989; 243: 126-137.
7. Dearborn, JT. and Harris, WH. High placement of an acetabular component inserted without cement in a revision total hip arthroplasty. Results after a mean of ten years. J Bone Joint Surg Am.
1999; 81: 469-480.
8. Della Valle, CJ., Shuaipaj, T., Berger, RA., Rosenberg, AG., Shott, S., Jacobs, JJ. and Galante, JO. 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: 1795-1800. 10.2106/JBJS.D.01818
9. Dorr, LD. and Wan, Z. Ten years of experience with porous acetabular components for revision surgery. Clin Orthop Relat Res.
1995; 319: 191-200.
10. Gerber, A., Pisan, M., Zurakowski, D. and Isler, B. Ganz reinforcement ring for reconstruction of acetabular defects in revision total hip arthroplasty. J Bone Joint Surg Am.
2003; 85: 2358-2364.
11. Goodman, S., Saastamoinen, H., Shasha, N. and Gross, A. Complications of ilioischial reconstruction rings in revision total hip arthroplasty. J Arthroplasty.
2004; 19: 436-446. 10.1016/j.arth.2003.11.015
12. Hallstrom, BR., Golladay, GJ., Vittetoe, DA. and Harris, WH. Cementless acetabular revision with the Harris-Galante porous prosthesis. Results after a minimum of ten years of follow-up. J Bone Joint Surg Am.
2004; 86: 1007-1011. 10.1302/0301-620X.86B7.14860
13. Harris, WH. Traumatic arthritis of the hip after dislocation and acetabular fractures: treatment by mold arthroplasty. An end-result study using a new method of result evaluation. J Bone Joint Surg Am.
1969; 51: 737-755.
14. Harris, WH. Wear and periprosthetic osteolysis: the problem. Clin Orthop Relat Res.
2001; 393: 66-70. 10.1097/00003086-200112000-00007
15. Hendricks, KJ. and Harris, WH. High placement of noncemented acetabular components in revision total hip arthroplasty. A concise follow-up, at a minimum of fifteen years, of a previous report. J Bone Joint Surg Am.
2006; 88: 2231-2236. 10.2106/JBJS.E.00247
16. Hendricks, KJ. and Harris, WH. Revision of failed acetabular components with use of so-called jumbo noncemented components. A concise follow-up of a previous report. J Bone Joint Surg Am.
2006; 88: 559-563. 10.2106/JBJS.E.00389
17. Hooten, JP, Jr, Engh, CA, Jr, and Engh, CA. Failure of structural acetabular allografts in cementless revision hip arthroplasty. J Bone Joint Surg Br.
1994; 76: 419-422.
18. Ingham, E. and Fisher, J. Biological reactions to wear debris in total joint replacement. Proc Inst Mech Eng H.
2000; 214: 21-37.
19. Jacobs, JJ., Roebuck, KA., Archibeck, M., Hallab, NJ. and Glant, TT. Osteolysis: basic science. Clin Orthop Relat Res.
2001; 393: 71-77. 10.1097/00003086-200112000-00008
20. Jasty, M., Bragdon, C., Jiranek, W., Chandler, H., Maloney, W. and Harris, WH. Etiology of osteolysis around porous-coated cementless total hip arthroplasties. Clin Orthop Relat Res.
1994; 308: 111-126.
21. Koseki, H., Matsumoto, T., Ito, S., Doukawa, H., Enomoto, H. and Shindo, H. Analysis of polyethylene particles isolated from periprosthetic tissue of loosened hip arthroplasty and comparison with radiographic appearance. J Orthop Sci.
2005; 10: 284-290. 10.1007/s00776-005-0896-6
22. Kramhoft, M., Gehrchen, PM., Bodtker, S., Wagner, A. and Jensen, F. Inter- and intraobserver study of radiographic assessment of cemented total hip arthroplasties. J Arthroplasty.
1996; 11: 272-276. 10.1016/S0883-5403(96)80077-5
23. Lakstein, D., Backstein, D., Safir, O., Kosashvili, Y. and Gross, AE. Trabecular Metal cups for acetabular defects with 50% or less host bone contact. Clin Orthop Relat Res.
2009; 467: 2318-2324. 10.1007/s11999-009-0772-3
24. Lingaraj, K., Teo, YH. and Bergman, N. The management of severe acetabular bone defects in revision hip arthroplasty using modular porous metal components. J Bone Joint Surg Br.
2009; 91: 1555-1560. 10.1302/0301-620X.91B12.22517
25. Mall NA, Nunley RM, Smith KE, Maloney WJ, Clohisy JC, Barrack RL. The fate of grafting acetabular defects during revision total hip arthroplasty. Clin Orthop Relat Res.
2010 Jun 25. [Epub ahead of print].
26. Maloney, WJ., Herzwurm, P., Paprosky, W., Rubash, HE. and Engh, CA. Treatment of pelvic osteolysis associated with a stable acetabular component inserted without cement as part of a total hip replacement. J Bone Joint Surg Am.
1997; 79: 1628-1634.
27. Maloney, WJ., Paprosky, W., Engh, CA. and Rubash, H. Surgical treatment of pelvic osteolysis. Clin Orthop Relat Res.
2001; 393: 78-84. 10.1097/00003086-200112000-00009
28. Maloney, WJ., Smith, RL., Schmalzried, TP., Chiba, J., Huene, D. and Rubash, H. Isolation and characterization of wear particles generated in patients who have had failure of a hip arthroplasty without cement. J Bone Joint Surg Am.
1995; 77: 1301-1310.
29. McNamara, I., Deshpande, S. and Porteous, M. Impaction grafting of the acetabulum with a mixture of frozen, ground irradiated bone graft and porous synthetic bone substitute (Apapore 60). J Bone Joint Surg Br.
2010; 92: 617-623. 10.1302/0301-620X.92B5.23044
30. Mehendale, S., Learmonth, ID., Smith, EJ., Nedungayil, S., Maheshwari, R. and Hassaballa, MA. Use of irradiated bone graft for impaction grafting in acetabular revision surgery: a review of fifty consecutive cases. Hip Int.
2009; 19: 114-119.
31. Orishimo, KF., Claus, AM., Sychterz, CJ. and Engh, CA. Relationship between polyethylene wear and osteolysis in hips with a second-generation porous-coated cementless cup after seven years of follow-up. J Bone Joint Surg Am.
2003; 85: 1095-1099.
32. Park, DK., Della Valle, CJ., Quigley, L., Moric, M., Rosenberg, AG. and Galante, JO. Revision of the acetabular component without cement. A concise follow-up, at twenty to twenty-four years, of a previous report. J Bone Joint Surg Am.
2009; 91: 350-355. 10.2106/JBJS.H.00302
33. Pieringer, H., Auersperg, V. and Bohler, N. Reconstruction of severe acetabular bone-deficiency: the Burch-Schneider antiprotrusio cage in primary and revision total hip arthroplasty. J Arthroplasty.
2006; 21: 489-496. 10.1016/j.arth.2005.02.016
34. Regis, D., Magnan, B., Sandri, A. and Bartolozzi, P. Long-term results of anti-protrusion cage and massive allografts for the management of periprosthetic acetabular bone loss. J Arthroplasty.
2008; 23: 826-832. 10.1016/j.arth.2007.06.017
35. Rudelli, S., Honda, E., Viriato, SP., Libano, G. and Leite, LF. Acetabular revision with bone graft and cementless cup. J Arthroplasty
2009; 24: 432-443. 10.1016/j.arth.2007.11.022
36. Russotti, GM. and Harris, WH. Proximal placement of the acetabular component in total hip arthroplasty. A long-term follow-up study. J Bone Joint Surg Am.
1991; 73: 587-592.
37. Schlegel, UJ., Bitsch, RG., Pritsch, M., Aldinger, PR., Mau, H. and Breusch, SJ.[Acetabular reinforcement rings in revision total hip arthroplasty: midterm results in 298 cases]. Orthopade
2008; 37: (904):906-913.
38. Schmalzried, TP., Fowble, VA. and Amstutz, HC. The fate of pelvic osteolysis after reoperation. No recurrence with lesional treatment. Clin Orthop Relat Res.
1998; 350: 128-137. 10.1097/00003086-199805000-00018
39. Schmalzried, TP., Jasty, M. and Harris, WH. Periprosthetic bone loss in total hip arthroplasty. Polyethylene wear debris and the concept of the effective joint space. J Bone Joint Surg Am.
1992; 74: 849-863.
40. Schreurs, BW., Slooff, TJ., Gardeniers, JW. and Buma, P. Acetabular reconstruction with bone impaction grafting and a cemented cup: 20 years’ experience. Clin Orthop Relat Res.
2001; 393: 202-215. 10.1097/00003086-200112000-00023
41. Shinar, AA. and Harris, WH. Bulk structural autogenous grafts and allografts for reconstruction of the acetabulum in total hip arthroplasty. Sixteen-year-average follow-up. J Bone Joint Surg Am.
1997; 79: 159-168.
42. Slooff, TJ., Schimmel, JW. and Buma, P. Cemented fixation with bone grafts. Orthop Clin North Am.
1993; 24: 667-677.
43. Sporer, SM., O’Rourke, M., Chong, P. and Paprosky, WG. The use of structural distal femoral allografts for acetabular reconstruction. Average ten-year follow-up. J Bone Joint Surg Am.
2005; 87: 760-765. 10.2106/JBJS.D.02099
44. Sporer, SM., Paprosky, WG. and O’Rourke, M. Managing bone loss in acetabular revision. J Bone Joint Surg Am.
2005; 87: 1620-1630. 10.2106/JBJS.D.02099
45. Symeonides, PP., Petsatodes, GE., Pournaras, JD., Kapetanos, GA., Christodoulou, AG. and Marougiannis, DJ. The Effectiveness of the Burch-Schneider antiprotrusio cage for acetabular bone deficiency: five to twenty-one years’ follow-up. J Arthroplasty.
2009; 24: 168-174. 10.1016/j.arth.2007.10.009
46. Udomkiat, P., Wan, Z. and Dorr, LD. Comparison of preoperative radiographs and intraoperative findings of fixation of hemispheric porous-coated sockets. J Bone Joint Surg Am.
2001; 83: 1865-1870.
47. Kleunen, JP., Lee, GC., Lementowski, PW., Nelson, CL. and Garino, JP. Acetabular revisions using trabecular metal cups and augments. J Arthroplasty.
2009; 24: 64-68. 10.1016/j.arth.2009.02.001
48. Wedemeyer, C., Neuerburg, C., Heep, H., Knoch, F., Knoch, M., Loer, F. and Saxler, G. Jumbo cups for revision of acetabular defects after total hip arthroplasty: a retrospective review of a case series. Arch Orthop Trauma Surg.
2008; 128: 545-550. 10.1007/s00402-007-0501-x
49. Weeden, SH. and Paprosky, WG. Porous-ingrowth revision acetabular implants secured with peripheral screws. A minimum twelve-year follow-up. J Bone Joint Surg Am.
2006; 88: 1266-1271. 10.2106/JBJS.E.00540