Einat Slonimsky 1 , Tammar Kushnir 1 , Assaf Kadar 2 , Aharon Menahem 2 , Alon Grundshtein 2 , Shmuel Dekel 3 , Iris Eshed 4 Show Affiliations »
Abstract
BACKGROUND: Metal-on-metal (MoM) hip prostheses were shown to have high failure rates including the formation of periprosthetic cystic masses called periprosthetic pseudotumor collections (PPCs). PURPOSE: To compare MRI prevalence and size of PPCs in patients after bilateral total-hip-replacement (THR) in which at least one hip was replaced by a MoM prosthesis. MATERIAL AND METHODS: All sequential MRI examinations of patients with bilateral THR in which at least one is MoM (2010-2013) were retrospectively evaluated. MRIs were analyzed separately by two readers for the presence and size of PPCs. These were compared between MoM and non-MoM implants and between patients with unilateral or bilateral-MoM prostheses. Blood metal ion levels were also compared. RESULTS: Seventy hips of 35 patients (male:female ratio, 9:26; mean age, 64 years; age range, 35-82 years) were assessed. Sixteen patients (45%) underwent bilateral MoM-THRs and 19 (55%) had one MoM and the other non-MoM, yielding 51 MoM THRs and 19 non-MoM THRs. Twenty-eight PPCs were detected in 19 patients (54%): 26 in MoM THRs (51%) and two in non-MoM THRs (10.5%, P = 0.00009). The mean PPC volume in the MoM implants (107 mm(3)) was higher than that of the non-MoM implants (18 mm(3), P = 0.49). Cobalt/chromium blood levels were 78 µg/L/25 µg/L for bilateral MoM THRs and 21 µg/L/10 µg/L for unilateral MoM implants (P = 0.1 and 0.16, respectively). CONCLUSION: PPCs are more prevalent in MoM THRs compared to non-MoM THRs. Larger PPC volumes and higher blood metal ion levels were detected in patients with bilateral MoM THRs compared to unilateral MoM THRs (P > 0.05). © The Foundation Acta Radiologica 2015.
BACKGROUND: Metal -on-metal (MoM ) hip prostheses were shown to have high failure rates including the formation of periprosthetic cystic masses called periprosthetic pseudotumor collections (PPCs). PURPOSE: To compare MRI prevalence and size of PPCs in patients after bilateral total-hip-replacement (THR) in which at least one hip was replaced by a MoM prosthesis. MATERIAL AND METHODS: All sequential MRI examinations of patients with bilateral THR in which at least one is MoM (2010-2013) were retrospectively evaluated. MRIs were analyzed separately by two readers for the presence and size of PPCs. These were compared between MoM and non-MoM implants and between patients with unilateral or bilateral-MoM prostheses. Blood metal ion levels were also compared. RESULTS: Seventy hips of 35 patients (male:female ratio, 9:26; mean age, 64 years; age range, 35-82 years) were assessed. Sixteen patients (45%) underwent bilateral MoM -THRs and 19 (55%) had one MoM and the other non-MoM , yielding 51 MoM THRs and 19 non-MoM THRs . Twenty-eight PPCs were detected in 19 patients (54%): 26 in MoM THRs (51%) and two in non-MoM THRs (10.5%, P = 0.00009). The mean PPC volume in the MoM implants (107 mm(3)) was higher than that of the non-MoM implants (18 mm(3), P = 0.49). Cobalt /chromium blood levels were 78 µg/L/25 µg/L for bilateral MoM THRs and 21 µg/L/10 µg/L for unilateral MoM implants (P = 0.1 and 0.16, respectively). CONCLUSION: PPCs are more prevalent in MoM THRs compared to non-MoM THRs . Larger PPC volumes and higher blood metal ion levels were detected in patients with bilateral MoM THRs compared to unilateral MoM THRs (P > 0.05). © The Foundation Acta Radiologica 2015.
Entities: Chemical
Species
Keywords:
MRI; blood metal ions; hip replacement; metal-on-metal hip implant; pseudotumor
Mesh： See more »
Year: 2015
PMID： 25940064 DOI： 10.1177/0284185115583930
Source DB: PubMed Journal: Acta Radiol ISSN： 0284-1851 Impact factor: 1.990