Pseudotumor in ceramic-on-metal total hip arthroplasty

Abstract

The increasing demand for total hip arthroplasty (THA) in relatively young, high-demand patients has led to the use of hard-on-hard bearing surfaces. Adverse local tissue reaction/pseudotumor and elevated serum metal ion levels are commonly reported complications encountered in metal-on-metal THA, while audible articulation and rim fracture are reported in ceramic-on-ceramic THA. For this reason, ceramic-on-metal THA was implemented as an ideal hard-on-hard bearing combination. In this report, we describe a case of bilateral simultaneous ceramic-on-metal THA in a 69-year-old woman who presented 7 years postoperatively with unilateral hip pain associated with underlying pseudotumor and elevated serum cobalt and chromium ion levels. Pre-revision workup, intraoperative findings, and postoperative evaluation are included and suggest acetabular malposition as a potential source for complication.

Keywords: Adverse local tissue reaction; Ceramic-on-metal; Hard-on-hard; Pseudotumor; Total hip arthroplasty.

Figure 1

Anteroposterior (AP) pelvis radiograph at time of presentation to our clinic (7 years s/p simultaneous bilateral CoM THA) without signs of osteolysis or loosening.

Figure 2

Axial (T1) and coronal (T2) metal suppression magnetic resonance images of patient now 7.5 years out from simultaneous bilateral CoM THA notable for unilateral (right) cystic lesion (T1 and T2 hyperintense, pseudocapsular disruption, tracking anteriorly/proximally).

Figure 3

Intraoperative photograph of excised pseudocapsule and scar (taken surrounding area of femoral neck).

Figure 4

Intraoperative photographs of ceramic head with marked metal transfer on articulating surface and no significant corrosion/transfer noted in bore.

Figure 5

AP pelvis radiograph at 6 weeks s/p revision right THA with no obvious complication.

Figure 6

Coronal CT at 12 weeks s/p revision right THA, acetabular inclination 52° on right and 40° on left.

Figure 7

Axial CT at 12 weeks s/p revision right THA, acetabular anteversion 45° on right and 27° on left.

Figure 8

Axial (T1) and coronal (T2) metal suppression magnetic resonance images 6 months s/p revision right THA notable for small residual pseudotumor sheath with no fluid accumulation of the right and modestly enlarged left hip effusion.