- Components are fixed to bone with polymethylmethacrylate cement.
- Allows prosthesis to fit perfectly to irregularities of bone.
- Immediate stability allows for full activity post operatively
- If and when the prosthesis becomes loose, the loosened cement can grind away bone, leaving less bone stock available for revision surgery.
- Metal surfaces attaching to bone have a roughened surface coat
- Coating may be made of metal, ceramic, polymers, or combination of all these materials
- These materials are formed into beads, irregular particles, or etchings and applied to the prosthesis
- Irregularity allows for increased surface area
- All elbow prosthesis are cemented. Porous coating may be employed as an additional fixation method
|Metal etching about distal humeral and proximal ulnar component|
Flanged humeral components
The flange is built anteriorly, to grasp the humeral cortex and prevent posterior and torsional stresses at the humerus.
|Side view of Coonrad-Morrey humeral component removed from patient. The flange is anterior (blue arrow). The distal stem has a coated metallic bead surface to increase surface area to facilitate fixation. Note residual cement remains (red arrows).|