Faculty Collaboration Database

Magnetic resonance imaging findings in symptomatic versus asymptomatic subjects following metal-on-metal hip resurfacing arthroplasty. J Bone Joint Surg Am 2013 May 15;95(10):895-902

Date

05/17/2013

Pubmed ID

23677356

DOI

10.2106/JBJS.K.01476

Scopus ID

2-s2.0-84879775931 (requires institutional sign-in at Scopus site)   69 Citations

Abstract

BACKGROUND: Although pseudotumors have been reported at the sites of well-functioning and painful metal-on-metal hip prostheses, there are no objective data on the magnitude of the adverse reaction. This observational study was performed to investigate the ability of modified magnetic resonance imaging (MRI) to detect and quantify adverse synovial responses in symptomatic and asymptomatic subjects following metal-on-metal hip resurfacing. We hypothesized that the magnitude of the synovial reactions would be greater in symptomatic patients.

METHODS: Sixty-nine patients (seventy-four hips) with hip resurfacing were divided into three groups: asymptomatic (twenty-two hips), symptomatic with a mechanical cause (twenty), and unexplained pain (thirty-two). The volume of synovitis was calculated on MRI for all patients.

RESULTS: Synovitis was detected in fifteen asymptomatic hips (68%), fifteen (75%) with symptoms with a mechanical causes, and twenty-five (78%) with unexplained pain. The mean volume (and standard deviation) of the synovitis in these groups was 5 ± 7 cm³, 10 ± 16 cm³, and 31 ± 47 cm³, respectively. The coefficient of repeatability between the examiners was 1.8 cm³ for measurement of synovitis. Of the thirteen subjects with revision arthroplasty, six had an adverse local tissue reaction. This subgroup had the highest volumes of synovitis on MRI.

CONCLUSIONS: An adverse synovial reaction was detected on MRI in both symptomatic and asymptomatic subjects. We found a larger volume of synovitis in symptomatic patients; this increase reached significance only in the group with an adverse local tissue reaction. Synovial volume on MRI may be a valuable marker in the longitudinal assessment of asymptomatic patients with a metal-on-metal hip resurfacing and in identifying patients with adverse local tissue reaction.

Author List

Nawabi DH, Hayter CL, Su EP, Koff MF, Perino G, Gold SL, Koch KM, Potter HG

Author

Kevin M. Koch PhD Center Director, Professor in the Radiology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Arthroplasty, Replacement, Hip
Asymptomatic Diseases
Cohort Studies
Cross-Sectional Studies
Female
Foreign-Body Reaction
Hip Prosthesis
Humans
Magnetic Resonance Imaging
Male
Metal-on-Metal Joint Prostheses
Middle Aged
Osteolysis
Postoperative Complications
Prosthesis Failure
Reoperation
Reproducibility of Results
Synovitis