What the Surgeon Can Do to Reduce the Risk of Trunnionosis in Hip Arthroplasty: Recommendations from the Literature

Abstract

Trunnionosis, defined as wear and corrosion at the head-neck taper connection, is a cause of failure in hip arthroplasty. Trunnionosis is linked to a synergistic combination of factors related to the prosthesis, the patient, and the surgeon. This review presents analytical models that allow for the quantification of the impact of these factors, with the aim of providing practical recommendations to help surgeons minimize the occurrence of this failure mode. A tighter fit reduces micromotion and, consequently, fretting of the taper connection. The paramount parameters controlling the fixation force are the coefficient of friction and the impaction force. The influence of the head diameter, as well as of the diameter and angle of the taper, is comparatively small, but varus alignment of the taper and heads with longer necks are unfavourable under physiologic loads. The trunnion should be rinsed, cleaned, and dried carefully, while avoiding any contamination of the bore-the female counterpart within the head-prior to assembly. Biological debris, and even residual water, might critically reduce the fixation of the taper connection between the head and the neck. The impaction force applied to the components should correspond to at least two strong blows with a 500 g hammer, striking the head with an ad hoc impactor aligned with the axis of the taper. These strong blows should correspond to a minimum impaction force of 4000 N.

Quantification of assembly forces during creation of head-neck taper junction considering soft tissue bearing: a biomechanical study

“…In conclusion, the assembly forces determined showed a high variance among surgeons and they were low It can be assumed that the actual variance of the assembly forces might be even higher. Heads of different sizes and especially different materials differ in weight and different material combinations of head and stem have different friction properties at the interface [29]. These influencing factors could be investigated in further studies using the in vitro model developed.…”

Impending Trunnion Failure: An Uncommon Radiographic Presentation of Total Hip Arthroplasty Failure

“…Finally, implantation technique may also contribute to the development of trunnion wear. Thorough cleaning of the trunnion and greater impaction force at the time of head assembly are both associated with a decreased risk of trunnionosis [ 15 ].…”

It's worth cleaning – The examination of the female taper could identify a particular cause of trunnionosis at revision 16 years after total hip arthroplasty

“…Failure of metal-on-metal (MoM) total hip replacements (THR) due to local adverse reactions to metal debris (ARMD) is a well-known issue. [1,2] An additional reason for revision might be systemic toxicity of metal ions released from MoM THR, mainly with secondary neurologic, cardiac and immunologic disease. [3][4][5] Both issues lead to increased revision rates of THR with MoM bearings and might even be associated with an increased mortality.…”