Published online Feb 18, 2020. doi: 10.5312/wjo.v11.i2.116
Peer-review started: May 23, 2019
First decision: July 31, 2019
Revised: September 19, 2019
Accepted: November 28, 2019
Article in press: November 28, 2019
Published online: February 18, 2020
Processing time: 274 Days and 15.4 Hours
This unique presentation of hip swelling is only the seventh reported case of pseudotumor recurrence in a non-metal-on-metal total hip arthroplasty (THA) construct. The constellation of patient symptoms and laboratory findings contradict the expected elevated serum metal ion levels associated with the formation of pseudotumor. The presentation, lab trends, and imaging findings contribute to the growing base of knowledge surrounding the effects of corrosion in arthroplasty constructs with stem-neck modularity.
A 74-year-old man status post primary THA presented with left hip swelling and elevated serum metal ions five years after implantation of a modular stem-neck prosthesis. The swelling was diagnosed as pseudotumor based on laboratory trends and imaging findings and was treated with revision arthroplasty that completely resolved the initial hip swelling. The patient presented with recurrent hip swelling and recurrent pseudotumor findings on imaging in the same hip four months later. Non-operative management with ultrasound-guided hip aspiration resulted in symptom relief and resolution of the recurrent swelling. After one year of follow-up, the patient had no further recurrences of hip swelling.
This case of post-revision pseudotumor recurrence elucidates attributable patient, surgical, and implant factors with a discussion of diagnostics, management, and prognosis for patients with pseudotumor in non-metal-on-metal arthroplasty constructs.
Core tip: This unique presentation of hip swelling is only the seventh reported case of pseudotumor recurrence in a non-metal-on-metal total hip arthroplasty construct. These patients require a low threshold for clinical evaluation, using multiple modalities such as history, physical exam, magnetic resonance imaging, and serum metal ion level testing. The presentation, lab trends, and imaging findings of this case contribute to the growing base of knowledge surrounding the effects of corrosion in arthroplasty constructs with stem-neck modularity.