Meeting Banner
Abstract #1417

Magnetic Resonance Imaging Findings in Symptomatic Versus Asymptomatic Subjects Following Metal-On-Metal Hip Resurfacing Implants

MAGNA25Catherine L. Hayter1, Matthew F. Koff1, Edwin P. Su2, Kevin M. Koch3, Parina Shah1, Stephanie L. Gold1, Hollis G. Potter1

1Department of Radiology and Imaging - MRI, Hospital for Special Surgery, New York, United States; 2Center for Hip Pain and Preservation, Hospital for Special Surgery, New York, United States; 3Applied Science Laboratory, General Electric Healthcare, Waukesha, WI, United States

Metal-on-metal (MOM) hip resurfacing can be associated an adverse local tissue response (ALTR) which may manifest as synovitis or osteolysis. The purpose of this prospective, observational study was to review patterns of osteolysis and synovitis in symptomatic and asymptomatic individuals following MOM hip resurfacing. Synovitis was detected in a similar proportion of symptomatic and asymptomatic patients. Osteolysis was only detected in symptomatic individuals. The volume of synovitis was significantly higher in subjects with ALTR (p=0.01), as were levels of serum Cr (p=0.045) and Co (p=0.01). In the ALTR group there was a significantly higher proportion of females (p=0.048) and subjects with implants with abnormal acetabular component alignment (p=0.03). MRI is the most suitable non-invasive means by which to screen symptomatic and asymptomatic patients for the presence of synovitis. MRI can differentiate individuals with a normal pseudocapsule from those patients with synovitis, which, in combination with clinical findings and serum ion levels, will help to guide patient management. The finding of a high volume of synovitis on MRI should alert the clinician towards the need for close patient monitoring and possible revision surgery, particularly in the setting of elevated serum ion levels, female sex and abnormal component alignment.

Keywords

abnormal according acquisition adjacent adverse alert alignment alternative applied approved arrow arrows assessment asymptomatic axial board body bursa cardiac care categorized channel chromium classified clinical clinician close cobalt coefficient cohort coil collected combination component components comprising confirm consent consistent coronal correlate correlated correlation decompressing demographic despite detected differ differentiate disease divided duff electric elevated enrollment evaluated female females femur finding findings gender general gold good guide heavy help hips histology hospital implant implants increasingly index individuals infiltrate informed institutional intensity invasive laboratory length local manifest manual marrow mass matrix measured mechanical metal monitoring need observational operative overall pain particularly patient patients patterns placement potter presence preservation prospective radiographic radiology rank recorded records replacing response resurfacing review revision safe scanned scanners scanning screen serum setting shah shoulder significance significantly since slice special statistical subjects subset suitable support surgery symptomatic taken thick thin tissue tool towards underwent unexplained utility versus volume zone zones