The information contained in this document is intended for healthcare professionals only.

New Experience with Alumina:Alumina Ceramic Bearings for Total Hip Arthroplasty James A. D’Antonio, M.D. William N. Capello, M.D. Michael Manley, Ph.D.

New Experience with Alumina:Alumina Ceramic Bearings for Total Hip Arthroplasty James A. D’Antonio, M.D. William N. Capello, M.D. Michael Manley, Ph.D. Introduction offer great hope for reduced wear, long-term followup will be necessary to determine its true potential to limit debris release. When comparing hard-on-hard bearings, the ceramic-on-ceramic coupling has many theoretical advantages over metal-on-metal. Because of the ceramic’s extremely low coefficient of friction and its potential for superior wear resistance, these couples promise both wear rates that are appreciably less than polyethylene-on-metal...

Material and Methods: In October 1996, we began a US IDE prospective and randomized study comparing alumina-on-alumina ceramic bearings to chrome cobalt-on-polyethylene bearings. Patient enrollment was completed two years later in October 1998 after 514 hips were implanted in 458 patients. Twenty-two investigators at sixteen sites participated in this IDE study. There were initially three arms to the study, which included three cup designs. The two experimental systems used alumina-on-alumina bearings (Systems I and II). The control system used a chrome cobalton-polyethylene bearing (System III)....

Table I - ABC System – Patient Demographics* Demographics Number of Cases Number of Patients Male/Female % Mean Age (yrs.) Mean Weight (lbs.) Mean Height (inches) Length of Follow-up (months) Diagnosis Table II - Trident® System – Patient Demographics* Demographics Number of Cases Number of Patients Male/Female % Mean Age (yrs.) Mean Weight (lbs.) Mean Height (inches) Length of Follow-up (months) Diagnosis Trident® Shell Trident® Alumina Insert *All data based on database closure 9/30/00. Alumina Head Howmedica Osteonics Omnifit® HA Stem Trident® System

Results Nine insertions were chipped at the time of surgical insertion. In all but one instance the ceramic liner and/or shell was replaced. In one hip the chipped insert was seated, impacted and left in place without any known secondary complications. With regards to the Trident® arm of the study the complications are listed in Table V. Table VI provides a comparison of femoral head sizes used for the ABC alumina, the Trident® and the ABC control group of patients. There has been one revision of the femoral stem and alumina ceramic head in the Trident™ study group for a post-operative femoral...

Table V - Trident® System – Complications* Complication Revision-Acetabular Revision-Femoral Dislocation Heterotopic Bone Intra-Op Insert Chip Table VI - Comparison of Femoral Head Size* Head Size Trident ™ Alumina Components Control CoCr femoral heads *All data based on database closure 9/30/00. Discussion resistance is very attractive. Clinical experiences and retrievals of ceramic implants have indicated that ceramic debris is less reactive than metal or polyethylene debris9. In addition alumina ceramics are extremely hard, scratch resistant, stable at high temperatures and their hydrophilic...

Discussion continued from page 5 device failures were in large part design related rather than material related11. Both on the socket as well as the femoral side, the implants that were used were inferior to today’s designs with regards to achieving lasting fixation. In addition, the material itself was not of the same quality as the alumina ceramics available today. Since 1985 improvements have led to an alumina ceramic material that has a much reduced grain size, fewer inclusions and limited grain boundaries, all of which have led to a greater increase in toughness and burst strength of the...

Trident ® Ceramic Acetabular System: Case Study Patient This patient was first seen in October 1999 and presented as a 46-year-old female who had been suffering for several years with right groin and thigh pain. During the six months prior to the first visit she had become progressively disabled for activities of daily living. She noticed an increasing limp, could no longer walk for exercise, had rest pain and had difficulty dressing her lower extremity. The patient worked as a school principal. On examination she presented as a well-developed, well-nourished five-foot-two, 117 pound woman who...

Summary The addition of Trident® system to the study has provided for several advantages: • The Trident® shell allows for greater ease of liner insertion, somewhat greater ease of extraction, more intraoperative flexibility and more revision options. • The Trident® shell allows for independent locking mechanisms for the use of either ceramic or polyethylene inserts, either of which can be chosen at the time of surgery. • The Trident® study arm uses the same femoral stem, same ceramic heads and offers the addition of a 36 mm femoral head that further improves range of motion and stability of the...

The authors wish to acknowledge the investigators and co-investigators in the ABC study: Benjamin E. Bierbaum, M.D.* Paul Pongor, M.D. New England Baptist Hospital – Boston, MA Edward Hellman, M.D. Orthopaedics of Indianapolis – Indianapolis, IN Clifford W. Colwell, M.D. Steven Copp, M.D. Richard Walker, M.D Scripps Clinic – LaJolla, CA Jonathan Hottenstein, M.D. Sewickley Valley Hospital – Moon Township, PA Joseph H. Dimon, III, M.D. John D. Henry, M.D. Peachtree Orthopaedic Clinic – Atlanta, GA William Hozack, M.D. Rothman Institute – Philadelphia, PA William L. Jaffe, M.D. Paul DiCesare, M.D....

Stryker ® is a registered trademark of Stryker Corporation. Trident® ,Omnifit ®, Microstructured ®, and PSL® are registered trademarks of Howmedica Osteonics Corp. SecurFit™ is a trademark of Howmedica Osteonics Corp. Autophor ®, and Xenophor ® are not registered trademarks of Howmedica Osteonics Corp. © Howmedica Osteonics 2001, 2003 Lit. No. LSA33 7.5M 03/03 MC/ITP Printed in USA