The effect of stem geometry on stresses within the distal cement mantle in total hip replacement

Article type: Research Article

Authors: Schmölz, W.^{a; *} | Gordon, D.R.^a | Shields, A.J.^a | Kirkwood, D.^a | Grigoris, P.^b

Affiliations: [a] Department of Engineering, Glasgow Caledonian University, Cowcaddens Road Glasgow, G4 0BA, Scotland, UK | [b] Department of Orthopaedic Surgery, University of Glasgow, Western Infirmary Glasgow, G11 6NT, Scotland, UK

Correspondence: [*] Correspondence address: W. Schmölz, Dept. of Engineering, Glasgow Caledonian University, Cowcaddens Road, Glasgow G4 0BA, Scotland, UK. Tel.: +44 141 331 3592; Fax: +44 141 331 3690; E-mail: wsh@gcal.ac.uk

Abstract: Cement-stem debonding is one of the most common reasons for failure in Total Hip Replacement (THR). Four similar THR prostheses design configurations were investigated with reference to the influence of mechanical stress occurring in a cement mantle of differing thicknesses and potentially affecting clinical performance. Non-linear finite element analysis was performed on constant cement mantle thicknesses of 1, 2, and 4 millimetres. The results obtained indicate stress levels within the cement mantle decrease with increasing cement mantle thickness. The prosthesis distal tip is shown to have particular significance. Truncation of the distal tip hemisphere to a flat profile for the fixation of a centraliser increases the cement stresses.

DOI: 10.3233/THC-2000-8106

Journal: Technology and Health Care, vol. 8, no. 1, pp. 67-73, 2000