Medial Placement of a Cementless Acetabular Component in a Modern Alumina-on-Alumina THA

Abstract:

Medial placement of a cementless acetabular component into or beyond the medial wall of a shallow, dysplastic acetabulum is a technique to enhance its coverage during difficult total hip arthroplasty (THA). Dysplastic hips almost always need small size of acetabular component, so an accelerated polyethylene wear can occur when a conventional bearing surface is used. Modern alumina-on-alumina couplings can be an alternative for these patients. We evaluated the clinical results of 43 medially placed cementless acetabular components (PLASMACUP®SC) incorporating a modern alumina bearing surface (BIOLOX® forte). Acetabular components were inserted medially beyond the ilioischial line and, therefore, beyond the level of the cortical bone of the cotyloid notch, and followed up for more than 5 years (range, 60 – 93 months). In 14 hips, the medial acetabular wall was perforated purposefully and the medial aspect of the cup was placed beyond both the ilioischial and the iliopubic line on radiographs. The mean Harris hip score improved from 55.3 points preoperatively to 94.5 points postoperatively. Postoperatively, the hip center migrated 12.1 mm medially and 1.5 mm inferiorly. The average amount of cup protrusion beyond the ilioischial and the iliopubic line was 3.1 mm and 1.9 mm, respectively. The average superolateral coverage of the cup was 98.5 percent. During follow-up, no osteolysis or loosening of acetabular components was observed and no revision was required. Medial placement of a cementless acetabular component into or beyond the medial acetabular wall offers predictable clinical results and durable fixation in modern alumina-on-alumina THA.

• Periodical: Key Engineering Materials (Volumes 330-332)
• Pages: 1243-1246
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.330-332.1243
• Online since: February 2007
• Authors: Jeong Joon Yoo, Hee Joong Kim, Young Min Kim, Kang Sup Yoon, Kyung Hoi Koo, Kwang Woo Nam, Yong Lae Kim
• Keywords: Acetabular Component, Aluminum (Al), Bearing Surfaces, Ceramic, Medial Placement, Osteolysis, Total Hip Arthroplasty (THA)

References

[1] L.D. Dorr, S. Tawakkol, M. Moorthy, W. Long and Z. Wan: J Bone Joint Surg Am Vol 81 (1999), p.83.

[2] Y.H. Kim, J.S. Kim: J Arthroplasty Vol 20 (2005), p.1029.

[3] B. Erdemli, C. Yilmaz, H. Atalar, B. Güzel and I. Cetin. J Arthroplasty Vol 20 (2005), p.1021.

[4] W.H. Harris: Clin Orthop Vol 311 (1995), p.46.

[5] T.P. Schmalzried, M. Jasty and W.H. Harris: J Bone Joint Surg Am Vol 74 (1992), p.849.

[6] J.J. Yoo, Y.M. Kim, K.S. Yoon, K.H. Koo, W.S. Song and H.J. Kim: J Bone Joint Surg Am Vol 87 (2005), p.530.

[7] J.J. Yoo, Y.M. Kim, K.S. Yoon, K.H. Koo, J.W. Kim, K.W. Nam and H.J. Kim: J Biomed Mater Res B Appl Biomater Vol 78 (2006), p.70.

[8] J.J. Yoo, H.J. Kim, Y.M. Kim, K.S. Yoon, K.H. Koo, K.W. Nam and S.I. Shin: Key Eng Mater Vol 309-311 (2006), p.1353.

[9] W.H. Harris: J Bone Joint Surg Am Vol 51 (1969), p.737.

[10] G.M. Rossotti and W.H. Harris: J Bone Joint Surg Am Vol 73 (1991), p.587.