SpringerLink - Journal Article

Symposium: Papers Presented at the Hip Society Meetings 2008

Acetabular Loosening Using an Extended Offset Polyethylene Liner

Michael J. Archibeck¹, Tamara Cummins¹, Daniel W. Junick¹ and Richard E. White Jr.¹

(1)	New Mexico Center for Joint Replacement Surgery, New Mexico Orthopaedics, 201 Cedar SE, Suite 6600, Albuquerque, NM 87106, USA

Published online: 10 September 2008

Abstract The use of extended offset femoral components and acetabular liners helps restore preoperative offset during hip arthroplasty. We report a relatively high acetabular component aseptic loosening rate with the use of offset polyethylene liners. We reviewed 1919 primary and 346 revision total hip arthroplasties (THAs). A 7-mm offset acetabular liner was used in 120 of the primary and 100 of the revision THAs. The aseptic loosening rate in the primary THA group was 0.12% in the standard offset and 4.2% in the extended offset groups at a minimum of 2 years (mean, 3.6 years; range, 2–9 years) followup. The aseptic loosening rate in the revision group was 1.7% in the standard and 7% in the extended offset groups at a mean of 4 years (range, 2–9 years) followup. Although extended offset acetabular liners help restore hip offset, torsional force applied to the implant-bone interface may have a detrimental effect on fixation. We found a relatively high failure rate in our primary and revision acetabular components used with an offset liner.

Level of Evidence: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

One or more of the authors (MJA, REW) has received funding from Zimmer (Warsaw, IN).

Each author certifies that his or her institution has approved the human protocol for this investigation, that all investigations were conducted in conformity with ethical principles of research, and that informed consent for participation in the study was obtained.

Michael J. Archibeck
Email: archibeckmj@nmortho.net

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