Fracture of the ceramic femoral ball component
The fracture of the ceramic ball component may have severe consequences due to the character of the fracture. The material scientists call this type of fracture also the “burst” fracture because the ball “explodes” and splinters into several fragments, very many of them are of microscopic size. These small fragments are well dispersed in soft tissues around the total hip.
There the small, hard, and sharp ceramic particles mix with soft tissues and possibly with polyethylene particles and form a very effective abrasive paste. This has one serious consequence: If the soft tissues with abrasive paste are left in place at revision operation, the newly revised total hip – most often a model with a metal ball – will be effectively abraded into failure.
A large French statistics demonstrated that one third of revision operations done for burst fracture of the ceramic ball failed within five years (Allain 2003). 8% of these failures needed two or more further revision operations.
Factors leading to failure of a revision operation were incomplete removal of soft tissues around the fractured ceramic ball, replacement of the fractured ceramic ball with a “soft” stainless steel ball, and when the cup component (although seemingly intact) was left in place.
 Picture: - Ceramic Ball Fracture-Metallos |
Photograph of the second revision operation of a previously failed revision operation. Patient had a burst fracture of the ceramic ball with subsequent revision and replacement of the fractured ceramic ball with a metallic ball component. This metallic ball component (shown to the left in the picture) failed by severe abrasion through hard ceramic abrasion paste. The picture shows the large black deposits of metals abraded from the femoral ball. |
 Picture - Ceramic Ball Fracture - Abraded metallic ball : |
Photograph of the metallic femoral component removed at the second revision operation of the burst fracture of the ceramic head. The picture shows that large part of the ball’s surface was abraded. (Adapted from Allain 2003)
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_It is obvious that fracture of the ceramic ball component although rare is a very serious complication
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Reference:
Allain J et al.: Revision total hip arthroplasty performed after fracture of a ceramic femoral head. J Bone Joint Surg-Am 2003; 85-A: 825-30.