A Comparison of Large Diameter Metal Heads vs. Small Diameter Metal Heads vs/ Dual Mobility Total Hip Replacements
A Comparison of Large Diameter Metal Heads vs. Small Diameter Metal Heads vs/ Dual Mobility Total Hip Replacements
Does having a large diameter metal on polyethylene total hip replacement increase metal ion
 release. Larger metal heads are thought to have increased torsional forces on the trunion
 which would like release more metal ions. Increased metal ion levels have been associated
 with adverse local tissue reactions. Are there any differences comparing these groups to a
 dual mobility type total hip replacement.
Inclusion Criteria:

 -  One total hip replacement, either a large metal head (>40) or a small metal head (<30)
 on a polyethylene bearing surface.

 -  2 to 5 years s/p surgery minimum. No symptoms

 Exclusion Criteria:

 -  Any other bearing surface besides metal on poly, no other joint replacements,
 symptomatic