STP1471

    Corrosion of Modular Titanium Alloy Stems in Cementless Hip Replacement

    Published: Jan 2006


      Format Pages Price  
    PDF Version (2.5M) 10 $25   ADD TO CART
    Complete Source PDF (15M) 10 $65   ADD TO CART


    Abstract

    Severe, localized corrosion of titanium-alloy femoral stems has been reported for specific designs of hip prostheses intended for fixation using acrylic cement. The purpose of the present study was to examine the possibility that corrosion might also occur when titanium-alloy stems are inserted without cement, but the body of the stem is modular in design. Fourteen (7 primary and 7 revision) cementless, modular-body, titanium-6 % aluminum-4 % vanadium alloy femoral stems of similar design were removed at revision surgery after 2 to 108 months in situ. The reason for removal was unexplained pain (4), femoral or acetabular loosening (4), infection (3), recurrent dislocation (2), or component malposition (1). The devices and, in selected cases, tissue from the joint psuedocapsule were studied with the use of light and scanning electron microscopy. Fretting corrosion products were characterized using energy dispersive x-ray analysis, selected area diffraction, and micro-Raman spectroscopy. Damage at the modular body connections was absent in 3 stems, mild in 6, moderate in 4, and severe in 1. The surface damage was characterized predominately by fretting scars and by pitting and etching. Thick deposits of mixed titanium oxides were found adherent to the stem at the sites of corrosion and as 0.01 to 200 micrometer particles within histiocytes and multinucleated giant cells in the joint pseudocapsule. Fretting corrosion at the modular-body junctions of titanium-alloy femoral stems can generate solid degradation products, adding to the particulate biu-den of the periprosthetic tissues and potentially accelerating bearing-surface wear by a third-body mechanism. Both of these features can potentiate the development and progression of osteolysis. In addition, fretting corrosion can increase the potential for structural failure of the device. These findings stress the importance of the design of modular junctions to minimize corrosion and the generation of corrosion products.

    Keywords:

    titanium, corrosion, fretting, modularity, particulate debris, metal ions


    Author Information:

    Urban, RM
    Assistant Professor and Director, Implant Pathology Laboratory, Professor and Director Section of Biomaterials Research, and Director, Metal Ion Laboratory, Rush University Medical Center, Chicago, IL

    Gilbert, JL
    Professor and Associate Dean, Syracuse University, Syracuse, NY

    Jacobs, JJ
    Assistant Professor and Director, Implant Pathology Laboratory, Professor and Director Section of Biomaterials Research, and Director, Metal Ion Laboratory, Rush University Medical Center, Chicago, IL


    Paper ID: STP37558S

    Committee/Subcommittee: F04.19

    DOI: 10.1520/STP37558S


    CrossRef ASTM International is a member of CrossRef.