Trunnionosis: What We Should Know As an Orthopaedic Surgeon
Nishikant Kumar1*, Andalib Kashani1, John Mukhopadhayay1
Journal Title: Journal of Clinical Medical Research
The main question is what is Trunnionosis and what do we need to know as a surgeon. So trunnionosis is basically metallosis. It is the generation of metallic debris from a combination of motion at head on neck junction and an electrochemical corrosion [1,2].
Trunnion is part of the femoral stem where head gets engaged1; Corrosion of this part is called Trunnionosis. Taper is the slotted part of head which fits into trunnion of stem; corrosion of this part is called Taperosis (Fig. 1).
Trunnionosis is basically a electrochemical corrosion and metallosis due to micromotion and both are basically synergestic and generates huge amount of metallic particles . It causes the same adverse local tissue reaction as metal on metal heads as in ALVAL, Pseudotumours. Trunionosis also causes osteolysis .
Trunnion is an independent source of metal ion [3-5]. In Rush Clinical Series, 27 patients of THR were revised for advanced local tissue reaction secondary to head neck corrosion with metal on poly bearings. The revision rates because of trunnionosis was 4.3% between 2009-2013.