Revisión acetabular primaria: incidencia y mecanismos de utilización del injerto óseo / Primary Acetabular Revision: Incidence and Mechanisms of Bone Graft Use

Introducción: El recambio acetabular primario puede llegar a ser una intervención de gran complejidad en dependencia del defecto óseo existente. Las lesiones pueden ser segmentarias, cavitarias o combinadas. Este último patrón es el que se observa con mayor frecuencia en pérdidas óseas periprotésicas por aflojamiento aséptico. Objetivos: Mostrar la evolución de la cirugía de recambio en la artroplastia de cadera, y orientar al cirujano en la toma de decisiones de modo individualizado, para evitar las complicaciones. Método: Se realizó la investigación basada en el tema de estudio, mediante la revisión de libros de texto de la especialidad, artículos científicos publicados en diferentes bases de datos informáticas: Pubmed/MEDLINE, SciELO, BVS, Scopus, Ebsco, Google Scholar, Cochrane, así como otras consultas en bibliotecas médicas. Análisis de la información: Las prioridades en la planificación de la reconstrucción se establecen para proporcionar un implante estable, restaurar la masa ósea y optimizar la biomecánica de la cadera, aunque son los hallazgos intraoperatorios los que definitivamente indicarán el tipo de intervención a seguir. Las exigencias funcionales de los pacientes y las comorbilidades deben ser consideradas, así como el coste-efectividad de la reconstrucción planificada. Conclusiones: La artroplastia total de cadera ha demostrado mejorar significativamente la calidad de vida en pacientes, con una baja tasa de complicaciones. Para prevenir el aflojamiento aséptico es necesario ser cuidadosos en la técnica de colocación de los componentes protésicos y utilizar el tipo de material más adecuado a la edad, demanda funcional y reserva ósea de cada paciente(AU)

Introduction: Primary acetabular replacement can become a highly complex intervention depending on the existing bone defect. Lesions can be segmental, cavitary, or combined. This last pattern is the one most frequently observed in periprosthetic bone loss due to aseptic loosening. Objectives: To show the evolution of replacement surgery in hip arthroplasty, and to guide the surgeon in making individualized decisions, to avoid complications. Method: A research was carried out on the study topic, by reviewing specialty textbooks, scientific articles published in different databases such as Pubmed/ MEDLINE, SciELO, BVS, Scopus, Ebsco, Google Scholar, Cochrane, as well as other inquiries in medical libraries. Information analysis: Reconstruction planning priorities are established to provide a stable implant, restore bone mass, and optimize hip biomechanics, although it is the intraoperative findings that will definitely indicate the type of intervention to follow. The functional demands of the patients and the comorbidities must be considered, as well as the cost-effectiveness of the planned reconstruction. Conclusions: Total hip arthroplasty has been shown to significantly improve the quality of life in patients, with low rate of complications. To prevent aseptic loosening, it is necessary to be careful in the technique of placement of the prosthetic components and to use the type of material most appropriate to the age, functional demand and bone reserve of each patient(AU)

Acetabular Revision Using Cementless Acetabular Cup

PURPOSE: To evaluate implant survivorship and clinical outcomes after acetabular revision using cementless acetabular cups. MATERIALS AND METHODS: We evaluated 27 cementless acetabular revision cases performed between January 1998 and October 2005. All patients were followed up for more than 2 years, and the mean follow-up period was 54.1 months (range: 24~120 months). In all cases, morselized allografting was performed. Five cases needed structural allografting to achieve stability of the acetabular cup. The clinical results were analyzed using the Harris hip score, and radiological analysis was performed for evaluation of radiolucent lines, osteolysis, loosening, and changes in the hip center. RESULTS: At the time of latest follow-up, no cups showed failure requiring re-revision. The average Harris hip score improved from 67.1 points preoperatively to 91.4 points postoperatively. Radiologically, 7 cases (25.9%) showed radiolucent lines around the acetabular cup, but there was no loosening or osteolysis. CONCLUSION: Cementless acetabular revision showed satisfactory radiological and clinical results on short-term follow-up analysis. Even in cases with considerable amounts of acetabular bone loss, stable fixation could be obtained with structural bone grafting.

Cementless Acetabular Revision Performed with Morselized Bone Grafts:A Ten-Year Minimum Follow-Up

Purpose: We evaluated the results of cementless acetabular revisions performed with morselized bone grafting and screw-fixed hemispherical cups with different surface treatments. Materials and Methods: Forty hips, which had been followed for more than 10 years, were included in this study. Reconstruction was performed with 10 hydroxyapatite (HA)-coated cups and 30 porocoated ones. The mean followup time was 12 years and 1 months (range, 10 years to 15 years). Re-revision or radiographic loosening was considered as an endpoint of follow-up. Results: The average Harris hip score improved from 52 points to 75 points. During the follow-up period, radiographic loosening was observed in 17 hips. The loosened implants were HA-coated cups in 8 hips and porocoated ones in 9 hips. In 14 of these, re-revision of the cups was performed. The re-revision rate was 20% for the porocoated cups and 80% for the HA-coated cups. There were 2 hips with liner wear, which had undergone liner and head changes. Bone grafts were united in all the hips. The average time to union was 5.2 months (range, 2 to 9 months), and the average time to incorporation was 12 months (range, 5 to 18 months). Conclusion: Our results imply that HA-coated cups have a significantly higher failure rate compared with the porocoated ones (P<0.05) after a minimum follow-up of 10 years. Morselized bone grafting with use of a porocoated cup is an effective modality, which can restore the bone loss of the acetabulum in revision total hip arthroplasty.

Comparison of Monoblock and Modular Femoral Stem on Isolated Acetabular Revision with Use of Uncemented Cup

Purpose: The purpose of our study was to assess the clinical and radiological results of isolated acetabular revision and the differences in the results between monoblock and modular femoral stems. Materials and Methods: Between October 1991 and June 2002, 39 patients (39 hips) underwent isolated acetabular revisions with use of uncemented cups and bone grafts. The mean period of follow-up was 5 years 3 months (range, 2 years 1 month to 9 years 8 months). The mean age of the patients at the time of the surgery was 51 years old (range, 26 to 75 years old). The monoblock femoral stems were used in 19 hips and the modular femoral stems were used in 20 hips. The monoblock stems were retained without exchange provided that there was no gross scratch on the femoral head and the femoral stem was confirmed to be stable and fixed intraoperatively. In the modular stems, the femoral heads were always exchanged with new ones. Results: The mean Harris hip score improved from 57 to 87 points. Radiologically, all the stems retained at surgery remained well osseointegrated without osteolysis. Re-revisions of the acetabular components were performed in 5 hips using monoblock stems due to periacetabular osteolysis caused by excessive wear of polyethylene and subsequent loosening of the cups in 3 hips and mechanically unstable acetabular cups without osteolysis in 2 hips. The mean wear rate of polyethylene coupled with the monoblock stem was 0.27 mm/year which was greater than the 0.11 mm/year in the cases with modular stems. Conclusion: To prevent failure of acetabular cups that may occur later by excessive wear of polyethylene, we recommend revision of the well-fixed monoblock femoral stems even though there is no gross scratch on the femoral heads of the monoblock stems.

Acetabular Rebision Using Acetabular Reinforcement Ring and Allograft Impaction

Purpose: We wanted to evaluate the clinical and radiologic results of acetabular revision using the acetabular reinforcement ring and also the allograft impaction in the acetabulum having deficient bone stock. Material and Methods: Nineteen hips revision arthroplasty were performed in 18 patients (9 males and 9 females) with using an acetabular reinforcement ring and allograft between July 1993 and December 2003. The patients were followed for an average of 64 months (range: 24-153). The mean age at the time of arthroplasty was 59 years old (range: 34-76). The causes of revision were aseptic loosening of the acetabular component in 16 cases, severe progressive osteolysis around the acetabular component in 2 cases and Girdlestone state after infected total hip arthroplasty in one case. The acetabular deficiency was type II in 5 hips, type III in 13 hips, and type IV in one hip according to the AAOS classification. The clinical results were evaluated using the modified Harris hip score, and the radiologic results were evaluated by assessing the preoperative and serial follow-up radiographs. Results: The mean preoperative Harris hip score of 47 was improved to 86 points at the latest follow-up. Periacetabular osteolysis was found in 2 cases, which did not progress at follow-up. The anatomic hip center was restored after revision arthroplasty (p<0.05). Complications were dislocation in 2 cases, breakage of the hook of the Ganz ring in one case, heterotopic ossification in one case and femoral artery injury in one case. All cases showed stable fixation of the acetabular component and good remodelling of the impacted allograft. There was neither recurrence of dislocation nor progression of the acetabular component loosening on the radiographs. Conclusion: Acetabular revision with acetabular reinforcement ring and allograft impaction showed satisfactory clinical and radiologic results with restoration of the hip center and consolidation of the allograft.

Clinical and Radiological Results of Revision Acetabular Arthroplasty using an Acetabular Roof Reinforcement Ring / 대한정형외과학회잡지

PURPOSE: We evaluated the clinical and radiological results of acetabular reconstructions using an acetabular roof reinforcement ring (ARR). MATERIALS AND METHODS: From May 1993 to November 1999, 18 hips revised with ARR were evaluated. The mean age at operation was 53 years. The average follow-up period was 51 months (24-94 months). Acetabular defects were classified based on the AAOS classification system. There was one case of type IIA defect, six cases of type IIB defect, ten cases of type III defect and one case of type IV defect. All were treated with morselized allografts and autografts, and three were reconstructed with additional structural autografts. RESULTS: The average Harris hip score improved from 54 preoperatively to 76 postoperatively, but five patients complained of intermittent hip pain. On the last follow-up radiographs, the bone grafts were united and remodeled in all cases, but only partial resorption was observed in two hips. We found evidence of osteolysis in four hips and observed cup migration in three hips. Three hips, in which Muller rings were used, were re-revised during the follow-up period. CONCLUSION: Acetabular reconstruction using ARR led to good clinical and radiological results, but a relative high rate of rerevision was shown in the cases fitted with the Muller ring. Appropriate ARR should be used depending on the extent of the acetabular defect.

Acetabular Revision Total Hip Arthroplasty Using Uncemented Cup and Morselized Impacted Allograft / 대한정형외과학회잡지

PURPOSE: This study was undertaken to evaluate the clinical and radiographic results of acetabular revision arthroplasty using an uncemented big cup and a morselized impacted allograft. MATERIALS AND METHODS: This study involved 81 hips of 77 patients experienced over a 2 year period (2-8 years 10 months). The bone defects of the acetabulum were classified by AAOS classification and by the Paprosky classification. We inserted an uncemented hemispherical cup by press-fitting technique as large size as possible. Only morselized impacted allograft was used for the bone defect. RESULTS: The average Harris hip score was 95.9. One case (Paprosky type IIIB) received revision with only morselized allograft and failed to achieve initial stability. Therefore re-revision was performed with tricortical autograft and morselized allograft which has been well maintained until now for 3.5 years. Vertical migration and horizontal migration of more than 3 mm were noted in five cases and two cases, respectively. Rotational migration of more than 8 degree was not noted. A radiolucent line between bone and cup was seen in 9 cases, and a radiolucent line between host bone and grafted bone in 2 cases, this line was less than 2 mm large. CONCLUSION: We believe this method is a good option in revision acetabular total hip arthroplasty.

Acetabular Revision with Hemispherical Porous Coated Prosthesis / 대한정형외과학회잡지

PURPOSE: To report the results of acetabular revisions performed with the cementless, hemi-spherical porous coated component supported by viable host bone and minimal allobone graft for acetabular deficiencies. MATERIALS AND METHODS: A retrospective study was completed for 22-revision acetabular components, using the cementless hemispherical porous coated prosthesis and minimal femoral head allograft. There was an average follow up of 48 months, with a range of 24 to 84 months. Radiographic measurements were performed in several aspects; cup-allograft contact, inclination, vertical and horizontal migration of acetabular cup, and acetabular zone by modified zone of DeLee and Charnley, in which location, size and progression or non-progression of radiolucent zone were recorded. The acetabular deficiencies were classified by the American Academy of Orthopaedic Surgeons Committee and were type I in 2 hips (9%), type II in 12 hips (55%), and type III in 8 hips (36%). Twenty acetabular cup cases of Harris-Galante II were used in this study, 1 case of Harris- Galante I, and 1 case of Duraloc. The average size of the cup was 57(44-66) mm. RESULTS: The average cup-allograft contact was 72.5% in 19 cases and we could not differentiate the margin between the host bone and the allograft in 3 cases. There was no significant vertical or horizontal migration of acetabular cup. Radiolucent zones in follow-up radiographs were 8 cases in zone IA, 4 cases in zone IB, 4 cases in zone IIB, 9 cases in zone IIC, 8 cases in zone IIIA, and 7 cases in zone IIIB. One case showed 2 mm radiolucent area in zone IIC and another case showed 3 mm radiolucent area in zone IIB, but the radiolucencies were not progressive. The remaining cases showed less than 0.5 mm radiolucent area or no radiolucent zone. The average period of bony incorporation was 13.1 months. CONCLUSIONS: We suppose that acetabular revision with the cementless hemispherical porous coated cup supported by viable host bone and minimal bone graft produces good results.

Cementless Acetabular Revision using Morselized Bone Grafts and Screw Fixed Hemispherical Cup / 대한정형외과학회잡지

The purpose of this study is to evaiuate the results of the reconstruction of acetabular bone defect with morselized bone graft and screw fixed hemispherical cup in revision of failed acetabular cup. Thirty four revisions of an acetabular component that had been performed in 34 patients between 1988 and 1993 at SNUH, and had followed more than four years were included in this study. The revised acetabulum was evaluated clinically by Harris hip score and radiologically by evaluating the osseous union, incorporation and resorption of graft, the amount of migration and cup angle change of revised components and periacetabular radiolucency. The mean Harris hip score was improved 52 to 84. All of the bone grafts united by 6.4 months and incorporated by 13.1 months. The graft bone resorption less than onefourth of the initial graft thickness was 91.2% (31 cases). There was no significant difference between pure allograft and allograft mixed with autograft in clinical and radiological results. Of 34 cases, 2 cases (5.9%) required rerevision of acetabulum for aseptic loosening. The two complications, postoperative infection and trochanteric bursitis were managed successfully with conservative methods. The results of the present study confirm the success of revision of the acetabulum with use of a hemispherical component stabilized with multiple small screws and morselized bone grafts filling bone defects.

Acetabular Revision by Using Femoral Head Allograft and Uncemented Cup / 대한정형외과학회잡지

Acetabular bone deficiencies encountered during the revision hip arthroplasties should be recon- structed to provide the implant stability and to restore the normal center of rotation of hip and the leg length. We revised the loosened acetabular cup by grafting fresh-frozen bulk femoral head and inserting uncemented cup in 17 hips of 15 patients. The average follow-up period was 2 years and 3 months. The acetabular bone deficiencies were type 2A in 6 hips, type 2B in 8, type 3A in 1 and type 3B in 2 by Paprosky's classification. Three blocks of femoral head were grafted in 3 type 3 deficiencies, but only one in type 2 deficiencies. The cup-host bone contact was 41% on the average. However, the cup-host bone contact in the zone I was present only in 12 out of 17 hips and its average was 14%. Incorporation of the allograft into the host bone occurred between 5 months and 1 year and 7 months (average, 8,6 months) after revision surgery. Significant radiographic loosening sign was noted only in 2 hips which had not only type 3B bone deficiencies reconstructed with 3 blocks of femoral head allograft but also no cup-host bone contact in zone I . The bulk allograft of fresh-frozen femoral head demonstrated acceptable results in type 2 acetabular bone deficiencies, although the follow-up period was relatively short. Reconstruction of type 3B acetabular bone deficiencies by using multiple blocks of femoral head allograft had been failed. We presumed that the lack of the graft stability and the intimate contact between the grafts and host bone was the cause of failure.

Reconstruction of the Acetabular Bone Defect with Morselized Bone Grafts in Acetabular Cup Revision Screw fixed Hemispherical Cup vs. Bipolar Cup / 대한정형외과학회잡지

The purpose of this study is to evaluate the results of the reconstruction of acetabular bone defect with morselized bone graft in revision of failed acetabular cup, used screw fixed hemispherical cup or bipolar cup as a component. Forty five revisions of an acetabular component that had been performed in 42 patients between 1988 and 1993 at SNUH, and had followed more than two years were included in this study. The revised acetabulum was evaluated by Harris hip score, in terms of osseous union and resorption of the graft, the amount of the migration of the revised components. Cup angle change and radiolucency were also evaluated in screw fixed hemispherical cup. The mean Harris hip score was improved 54 to 87 in screw fixed hemispherical cup and 56 to 78 in bipolar cup. In screw fixed hemispherical cup, osseous union showed within 6 months is 91.3% (21 cases), the graft bone resorption less than 10% of the initial graft thickness is 73.9% (17 cases). In bipolar cup, osseous union within 6 months is 52.2% (12 cases), the graft bone resorption less than 10% of the initial graft thickness is 40.9% (9 cases). The failure of revised acetabular component was five in bipolar cup cases and one in screw fixed hemispherical cup cases. In conclusion, screw fixed hemispherical cup showed better clinical results, earlier graft osseous union, less graft bone resorption and lower failure rate than bipolar cup. There was no significant difference between pure allograft mixed with autograft in clinical and radiological results. So we recommend the technique used morselized allograft with screw fixed hemispherical cup, to reconstruct the acetabular bone defect in acetabular cup revision, though bipolar cup was used in staged operation in severe acetabular bone defect with was unable to fix the acetabular cup with screws.