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Fifteen-year survivorship of uncemented Harris-Galante I acetabular cup
Abstracts From the AAHKS Thirteenth Annual Meeting POSTER #14 EARLY FAILURE IN TOTAL HIP ARTHROPLASTY Matthew Dobzyniak, MD, Thomas K. Fehring, MD, Susan Odum, MEd, MA, William L. Griffin, MD, J. Bohannon Mason, MD, Thomas H. McCoy, MD Purpose: The purpose of this study was to analyze the mechanisms of failure in patients revised within five years of their index arthroplasty. Methods: Between 1986 and 2001, 824 revision total hip arthroplasty (THA) were performed. Arthroplasties that failed within five years of index arthroplasty were analyzed.
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Methods: The clinical and radiographic results from a consecutive series of 220 primary PCL-retaining TKR (148 patients) with RA were reviewed. Age at operation averaged 62 years. Follow-up averaged ten years. Results: Knee scores at 5, 10, 15, and 20 years averaged 86, 83, 88, and 89, respectively. Five knees (2.4%) were revised for deep infection. No femoral component aseptic loosening was noted. Three other tibial components were revised (1.4%); one for aseptic loosening and two for instability (both associated with pre-operative valgus deformity and ipsilateral plano-valgus. Excluding infections and failed metal-backed patellae, 5, 10, and 15 year Kaplan-Meier survival (loosening or revision) was 99.5%, 97.9%, and 96.5%, respectively. Conclusion: Favorable long-term results may be achieved with PCL-retaining TKR in patients with RA. Late rotational instability, associated with an ipsilateal plano-valgus deformity, is a concern.
Results: 745 revisions had complete data. 297 (40%) underwent revision within five years of their index arthroplasty. 114 (38%) were revised for aseptic loosening, 101 (33%) for instability, 41 (14%) for infection, 20 (7%) for osteolysis, 11 (4%) for painful hemiarthroplasties, and 10 (4%) for periprosthetic fracture. Early revisions for aseptic loosening decreased from 50% from 1986-1991 to 36% from 1992-1996 to 34% from 1997-2001. Discussion and Conclusion: The fact that 40% of revisions performed in our institution were completed in the first five years after index surgery is an alarming statistic. Steps to avoid such short-term failure must be taken.
POSTER #18
POSTER #15 MODULAR FEMORAL HEAD AND LINER EXCHANGE FOR THE UNSTABLE TOTAL HIP REPLACEMENT Ayaz Biviji, MD, Kace Ezzet, MD, Mary S. Tuason, BA, Pamela Pulido, BSN, Clifford W. Colwell, Jr., MD Introduction: Modular femoral head and acetabular liner exchange is accepted for recurrent hip dislocation after THR. This study evaluates modular exchange in treating hip instability. Methods: Demographic, clinical, and prosthetic data were collected by chart review and phone survey. Dislocation timing and direction, previous revision surgery, and head and acetabular cup size were examined as possible outcome predictors; failure was two or more redislocations or further surgery.
FIFTEEN-YEAR SURVIVORSHIP OF UNCEMENTED HARRIS-GALANTE I ACETABULAR CUP Javad Parvizi, MD, Gavan Duffy, Thomas Sullivan, Miguel Cabanela, MD We studied the long-term outcome of uncemented total hip arthroplasty using HG-I components in 90 hips (80 patients) with an average age of 57.5 years who were operated on between 1984 and 1986 at our institution. Average follow-up was 14.9 years and no patient was lost to follow-up. Hip scores improved significantly and there was clinical and radiographic evidence of bony ingrowth on the acetabular components in all patients. There were eleven revisions in the study population for reasons related to failure of femoral component (eight hips), acetabular liner dissociation (two hips) and deep infection (one hip). At the latest follow-up, three femoral components were determined to be loose. No acetabular component was revised for aseptic loosening. In addition to the revisions there were two reoperations, one for psoas tendon release, and one for excision of heterotopic ossification. Thus, the survivorship free of revision and free of mechanical failure for the acetabular component at 15 years was 95.7% (95% CI: 0.89-1.0) and 91.9% (95% CI: 0.83-0.98) respectively. The survivorship at 15 years for the femoral component was 86.8% (95% CI: 0.78-0.95) free of revision and 82.0 % (95% CI: 0.71-0.92) free of mechanical failure.
Results: Minimum 2-year follow-up data was available for 42 modular exchanges. The average time from surgery to first dislocation was 8.9(0-45.5) months. Average dislocations prior to exchange were 3.1(1-6); average age at surgery was 69.8 (51.6-87.7). Twenty-eight patients, no further dislocations, and two patients with one dislocation each were considered successful (71% overall). Twelve patients (29%) failed treatment; nine (21 %) had further revision. Factors examined were not outcome predictors. Conclusion: Modular component exchange can be successful in treating recurrent dislocations.
POSTER #19
POSTER #16 MODULAR CONSTRAINED DEVICES AND RECONSTRUCTION CAGES IN THE MANAGEMENT OF THE UNSTABLE HIP IN MAJOR ACETABULAR DEFICIENCY Adolph V. Lombardi, Jr., MD, FACS, Keith R. Berend, MD, Thomas H. Mallory, MD, FACS, Kathleen L. Dodds, BS, RN, Joanne B. Adams, BFA We retrospectively reviewed 26 patients with 28 acetabular reconstructions using constrained liner and modular, metalbacked components cemented into a reconstruction cage. All deficiencies were Type IIIC. Overall, the reoperation rate was 39.3%, including 3 aseptic failures, each occurring with breakage and failure of superior, then inferior fixation, then superomedial migration; 2 dislocations despite the constraint; and 4 deep infections. Mean HHS improvement was 36.2 points. The use of allograft bone, different component and/or cage designs was not significant for revision or infection (p⬎0.05). This technique is effective for extensive bone loss with instability. Modularity allows for position fine-tuning and exchange if needed.
POSTER #17 LONG-TERM FOLLOW-UP OF POSTERIOR CRUCIATE RETAINING TKR IN RHEUMATOID ARTHRITIS PATIENTS John Meding, MD, E. Michael Keating, MD, Merrill A. Ritter, MD, Philip M. Faris, MD, Michael E. Berend, MD Purpose: To review the long-term results of posterior cruciate ligament (PCL)–retaining total knee replacement (TKR) in patients with rheumatoid arthritis (RA).
AT WHAT STEPS IN THE PERFORMANCE OF A TKA DO ERRORS OCCUR WHEN MANUAL INSTRUMENTATION IS USED? S. David Stulberg, MD, Odell Woods, Angie Adams Introduction: Computer assisted navigation tools make it possible to measure the accuracy with which each step of a total knee replacement is performed using conventional manual instrumentation. Using these tools, we have shown that the placement of the femoral and tibial cutting blocks using manual instrumentation is inconsistent and often inaccurate. The purpose of this study is to determine when during the performance of each step of a TKR errors occur, and to quantify the magnitude of these errors. Methods: 25 TKR were performed using a manual, intra-medullary based alignment system. The accuracy of each step of the procedure was measured using an image-free navigation system (OrthoPilot娀). The steps measured were: 1) initial positioning of the distal femoral cutting block, anterior-posterior cutting block, and proximal tibial cutting block; 2) effect of pinning on the position of each of the cutting blocks; 3) accuracy of resection using each of the cutting blocks; and 4) accuracy of final positioning of the femoral and tibial implants. Perfect alignment was defined as placement of the femoral and tibial blocks and implants at 90 degrees to the mechanical axis in the frontal plane and parallel to the mechanical axis in the sagittal plane. Results: Initial positioning of the femoral and tibial cutting blocks was most accurate and consistent in the frontal plane (average alignment: 89 degrees, range: 87-91 degrees) and least accurate in the sagittal plane (average alignment: 3 degrees, range ⫺6 to ⫹ 6 degrees). Manual pinning of the blocks was associated with substantial (average, 4 degrees) but difficult to visualize change from initial positioning; Resection through slots introduced small average errors (1 degree), but a wide range (5 degrees) of variation; final femoral implant positioning was associated with a small error (⬍ 1 degree), but final tibial implant positioning introduced an average error of 2 degrees into hyperextension. Conclusions: Computer assisted techniques allow accurate measurement of each step of the TKR procedure. Substantial errors occur during the performance of each step of the surgical procedure when performed using manual instruments. An awareness of the potential for the occurrence of these errors can lead to changes in technique (e.g. inserting pins into blocks with power equipment) and improvements in manual instruments (e.g. cutting blocks with slots that limit saw blade deflection).
263
Methods: The clinical and radiographic results from a consecutive series of 220 primary PCL-retaining TKR (148 patients) with RA were reviewed. Age at operation averaged 62 years. Follow-up averaged ten years. Results: Knee scores at 5, 10, 15, and 20 years averaged 86, 83, 88, and 89, respectively. Five knees (2.4%) were revised for deep infection. No femoral component aseptic loosening was noted. Three other tibial components were revised (1.4%); one for aseptic loosening and two for instability (both associated with pre-operative valgus deformity and ipsilateral plano-valgus. Excluding infections and failed metal-backed patellae, 5, 10, and 15 year Kaplan-Meier survival (loosening or revision) was 99.5%, 97.9%, and 96.5%, respectively. Conclusion: Favorable long-term results may be achieved with PCL-retaining TKR in patients with RA. Late rotational instability, associated with an ipsilateal plano-valgus deformity, is a concern.
Results: 745 revisions had complete data. 297 (40%) underwent revision within five years of their index arthroplasty. 114 (38%) were revised for aseptic loosening, 101 (33%) for instability, 41 (14%) for infection, 20 (7%) for osteolysis, 11 (4%) for painful hemiarthroplasties, and 10 (4%) for periprosthetic fracture. Early revisions for aseptic loosening decreased from 50% from 1986-1991 to 36% from 1992-1996 to 34% from 1997-2001. Discussion and Conclusion: The fact that 40% of revisions performed in our institution were completed in the first five years after index surgery is an alarming statistic. Steps to avoid such short-term failure must be taken.
POSTER #18
POSTER #15 MODULAR FEMORAL HEAD AND LINER EXCHANGE FOR THE UNSTABLE TOTAL HIP REPLACEMENT Ayaz Biviji, MD, Kace Ezzet, MD, Mary S. Tuason, BA, Pamela Pulido, BSN, Clifford W. Colwell, Jr., MD Introduction: Modular femoral head and acetabular liner exchange is accepted for recurrent hip dislocation after THR. This study evaluates modular exchange in treating hip instability. Methods: Demographic, clinical, and prosthetic data were collected by chart review and phone survey. Dislocation timing and direction, previous revision surgery, and head and acetabular cup size were examined as possible outcome predictors; failure was two or more redislocations or further surgery.
FIFTEEN-YEAR SURVIVORSHIP OF UNCEMENTED HARRIS-GALANTE I ACETABULAR CUP Javad Parvizi, MD, Gavan Duffy, Thomas Sullivan, Miguel Cabanela, MD We studied the long-term outcome of uncemented total hip arthroplasty using HG-I components in 90 hips (80 patients) with an average age of 57.5 years who were operated on between 1984 and 1986 at our institution. Average follow-up was 14.9 years and no patient was lost to follow-up. Hip scores improved significantly and there was clinical and radiographic evidence of bony ingrowth on the acetabular components in all patients. There were eleven revisions in the study population for reasons related to failure of femoral component (eight hips), acetabular liner dissociation (two hips) and deep infection (one hip). At the latest follow-up, three femoral components were determined to be loose. No acetabular component was revised for aseptic loosening. In addition to the revisions there were two reoperations, one for psoas tendon release, and one for excision of heterotopic ossification. Thus, the survivorship free of revision and free of mechanical failure for the acetabular component at 15 years was 95.7% (95% CI: 0.89-1.0) and 91.9% (95% CI: 0.83-0.98) respectively. The survivorship at 15 years for the femoral component was 86.8% (95% CI: 0.78-0.95) free of revision and 82.0 % (95% CI: 0.71-0.92) free of mechanical failure.
Results: Minimum 2-year follow-up data was available for 42 modular exchanges. The average time from surgery to first dislocation was 8.9(0-45.5) months. Average dislocations prior to exchange were 3.1(1-6); average age at surgery was 69.8 (51.6-87.7). Twenty-eight patients, no further dislocations, and two patients with one dislocation each were considered successful (71% overall). Twelve patients (29%) failed treatment; nine (21 %) had further revision. Factors examined were not outcome predictors. Conclusion: Modular component exchange can be successful in treating recurrent dislocations.
POSTER #19
POSTER #16 MODULAR CONSTRAINED DEVICES AND RECONSTRUCTION CAGES IN THE MANAGEMENT OF THE UNSTABLE HIP IN MAJOR ACETABULAR DEFICIENCY Adolph V. Lombardi, Jr., MD, FACS, Keith R. Berend, MD, Thomas H. Mallory, MD, FACS, Kathleen L. Dodds, BS, RN, Joanne B. Adams, BFA We retrospectively reviewed 26 patients with 28 acetabular reconstructions using constrained liner and modular, metalbacked components cemented into a reconstruction cage. All deficiencies were Type IIIC. Overall, the reoperation rate was 39.3%, including 3 aseptic failures, each occurring with breakage and failure of superior, then inferior fixation, then superomedial migration; 2 dislocations despite the constraint; and 4 deep infections. Mean HHS improvement was 36.2 points. The use of allograft bone, different component and/or cage designs was not significant for revision or infection (p⬎0.05). This technique is effective for extensive bone loss with instability. Modularity allows for position fine-tuning and exchange if needed.
POSTER #17 LONG-TERM FOLLOW-UP OF POSTERIOR CRUCIATE RETAINING TKR IN RHEUMATOID ARTHRITIS PATIENTS John Meding, MD, E. Michael Keating, MD, Merrill A. Ritter, MD, Philip M. Faris, MD, Michael E. Berend, MD Purpose: To review the long-term results of posterior cruciate ligament (PCL)–retaining total knee replacement (TKR) in patients with rheumatoid arthritis (RA).
AT WHAT STEPS IN THE PERFORMANCE OF A TKA DO ERRORS OCCUR WHEN MANUAL INSTRUMENTATION IS USED? S. David Stulberg, MD, Odell Woods, Angie Adams Introduction: Computer assisted navigation tools make it possible to measure the accuracy with which each step of a total knee replacement is performed using conventional manual instrumentation. Using these tools, we have shown that the placement of the femoral and tibial cutting blocks using manual instrumentation is inconsistent and often inaccurate. The purpose of this study is to determine when during the performance of each step of a TKR errors occur, and to quantify the magnitude of these errors. Methods: 25 TKR were performed using a manual, intra-medullary based alignment system. The accuracy of each step of the procedure was measured using an image-free navigation system (OrthoPilot娀). The steps measured were: 1) initial positioning of the distal femoral cutting block, anterior-posterior cutting block, and proximal tibial cutting block; 2) effect of pinning on the position of each of the cutting blocks; 3) accuracy of resection using each of the cutting blocks; and 4) accuracy of final positioning of the femoral and tibial implants. Perfect alignment was defined as placement of the femoral and tibial blocks and implants at 90 degrees to the mechanical axis in the frontal plane and parallel to the mechanical axis in the sagittal plane. Results: Initial positioning of the femoral and tibial cutting blocks was most accurate and consistent in the frontal plane (average alignment: 89 degrees, range: 87-91 degrees) and least accurate in the sagittal plane (average alignment: 3 degrees, range ⫺6 to ⫹ 6 degrees). Manual pinning of the blocks was associated with substantial (average, 4 degrees) but difficult to visualize change from initial positioning; Resection through slots introduced small average errors (1 degree), but a wide range (5 degrees) of variation; final femoral implant positioning was associated with a small error (⬍ 1 degree), but final tibial implant positioning introduced an average error of 2 degrees into hyperextension. Conclusions: Computer assisted techniques allow accurate measurement of each step of the TKR procedure. Substantial errors occur during the performance of each step of the surgical procedure when performed using manual instruments. An awareness of the potential for the occurrence of these errors can lead to changes in technique (e.g. inserting pins into blocks with power equipment) and improvements in manual instruments (e.g. cutting blocks with slots that limit saw blade deflection).