Surface finish of the Exeter Trauma Stem… A Cause for Concern?

1. T. G. Petheram, MSc, FRCS(Tr & Orth), Orthopaedic Registrar1 ;
2. M. Bone, BEng, Research Assistant2;
3. T. J. Joyce, PhD, Professor of Orthopaedic Engineering2;
4. I. Serrano-Pedraza, PhD, Lecturer in Statistics3;
5. M. R. Reed, MD, FRCS(Tr & Orth), Consultant Orthopaedic Surgeon1 ; and
6. P. F. Partington, FRCS(Tr & Orth), Consultant Orthopaedic Surgeon1 

+Author Affiliations

1. 
   
   ¹Wansbeck General Hospital, Woodhorn Lane, Ashington, Northumberland NE63 9JJ, UK.
2. 
   
   ²Newcastle University, Claremont Road, Newcastle upon Tyne NE1 1RU, UK.
3. 
   
   ³Complutense University of Madrid, Campus De Somosaguas, Madrid 28223, Spain.

1. Correspondence should be sent to Mr T. G. Petheram; e-mail:timpetheram@hotmail.com

Abstract

Recent guidance recommends the use of a well-proven cemented femoral stem for hemiarthroplasty in the management of fractures of the femoral neck, and the Exeter Trauma Stem (ETS) has been suggested as an example of such an implant. The design of this stem was based on the well-proven Exeter Total Hip Replacement stem (ETHRS). This study assessed the surface finish of the ETS in comparison with the ETHRS. Two ETSs and two ETHRSs were examined using a profilometer with a precision of 1 nm and compared with an explanted Exeter Matt stem. The mean roughness average (RA) of the ETSs was approximately ten times higher than that of the ETHRSs (0.235 μm (0.095 to 0.452) versus 0.025 μm (0.011 to 0.059); p < 0.001). The historical Exeter Matt stem roughness measured a mean RA of 0.973 μm (0.658 to 1.159). The change of the polished Exeter stem to a matt surface finish in 1976 resulted in a high stem failure rate. We do not yet know whether the surface differences between ETS and ETHRS will be clinically significant. We propose the inclusion of hemiarthroplasty stems in national joint registries.

Cite this article: Bone Joint J 2013;95-B:173–6.

Footnotes

• The authors would like to thank the School of Mechanical and Systems Engineering, Newcastle University, for their help with this study.

  No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.