Delayed dislocation following metal-on-polyethylene arthroplasty of the hip due to ‘silent’ trunnion corrosion

Abstract

We present a case series of metal on polyethylene total hip replacement (MoP THR) with delayed onset dislocation, associated with unrecognised adverse local tissue reaction to trunnion corrosion and pseudotumour formation. The diagnosis was not suspected in nine of the ten cases, despite the subspecialty nature of the unit at which they were treated. Instead, it was identified at the time of revision surgery, because of the intraoperative findings, subsequently confirmed by histological examination of the resected tissue. Preoperative assessment and culture results ruled out infection.A variety of treatment strategies were employed, including tumour resection and efforts to avoid recurrent dislocation. The rate of complications was high and included three deep infections, two cases with recurrent dislocation, and one recurrent pseudotumour. This series demonstrates that pseudotumour is an infrequent but important cause of delayed instability following MoP THR, and it is easy to overlook in the differential diagnosis, especially if the original implant alignment is less than optimal, leading to an assumption of component malalignment as the cause of the dislocation.Revision is complex, requiring resection of the pseudotumour and modification of the reconstruction. The risk of postoperative complication is high.

A case of bilateral hip mechanically assisted crevice corrosion after staged total hip arthroplasty

“…In addition, recent literature also shows a high complication rate after revision for MACC/ALTR. One recent report has a total complication rate of 25%, with a 22% dislocation rate [14], with other studies noting dislocation rates between 7% and 20% [5], [29], [30], [31], [32]. So the fact that she had a dislocation after her second revision is not unexpected, though the specific cause of this instability is unknown [9].…”

The onset of fretting at the head‐stem connection in hip arthroplasty is affected by head material and trunnion design under simulated corrosion conditions

“…Only a few trunnion failures coupled with ceramic heads have been reported in the literature, while nearly all reported trunnionosis cases occurred with CoCr alloy heads . Retrieval studies and in vitro testing of ceramic heads suggest a reduction, but not the elimination, of trunnion fretting and corrosion .…”

“…Some THAs have been revised for catastrophic failure at the head–neck junction from corrosion‐related complications, while retrieval studies of head–neck couples revised for causes other than trunnion mechanical failure or ALTR have also frequently demonstrated evidence of fretting and corrosion . Severe trunnionosis was reported with the Accolade TMZF (titanium–molybdenum–zirconium–iron alloy), single wedge cementless stems with V40 trunnions and cobalt–chromium (CoCr) alloy heads (Stryker, Mahwah, NJ) . Similar reports were published of failures of Zimmer (Warsaw, IN) 12/14 trunnions on titanium alloy single wedge and CoCr alloy cementless stems with CoCr heads with additional reports of trunnionosis with the Zimmer 12/14 trunnion on cementless CoCr alloy stems and CoCr alloy heads .…”

Standardizing terms for tribocorrosion-associated adverse local tissue reaction in total hip arthroplasty

“…2). There is some controversy as to whether this is more common in mixed-alloy settings [13,14], which highlights the need for additional research to clarify this finding because there may be bias introduced by evaluating only retrieved implants (retrievals are primarily failed total hips, and corrosion may contribute to a failure, without being recognized [15,16]). Furthermore, retrieval laboratories estimating prevalence of corrosion based on visual inspection may have poor accuracy for lower grades (Goldberg 1-2) [17].…”