High grade MRI bone edema in rheumatoid arthritis patients undergoing joint replacement

High grade MRI bone edema is common within the surgical field in rheumatoid arthritis patients undergoing joint replacement and is associated with osteitis in subchondral bone.

Ann Rheum Dis. 2007 May 9
McQueen FM,
Gao A,
Ostergaard M,
King A,
Shalley G,
Robinson E,
Doyle A,
Clark B,
Dalbeth N.
Auckland University, New Zealand.

OBJECTIVES: /B> MRI bone oedema has been observed in early and advanced RA and may represent a cellular infiltrate (osteitis) in subchondral bone. We studied MRI scans from RA patients undergoing surgery, seeking to identify regions of bone oedema and examine its histopathological equivalent in resected bone.

METHODS: /B> Pre-operative contrast-enhanced MRI scans were obtained in 11 RA patients scheduled for orthopaedic surgery to the hands/wrists or feet. In 9, MRI scans were scored by 2 readers for bone oedema (RAMRIS system). Its distribution with respect to surgical site was investigated. In 4 patients, 7 bone samples were examined for a cellular infiltrate and this was compared with MRI bone oedema, scored for spatial extent and intensity.

RESULTS: /B> Inter-reader ICCs for bone oedema were 0.51 (all sites) and 0.98 (bone samples for histology). Bone oedema was observed at 60% of surgical sites vs 38% of non-surgical sites. High grade bone oedema (score = or >50% maximum) was strongly associated with the surgical field (OR 9.3 [3.5-24.2], P<0.0001). r="0.67," p="0.048)" r="0.86," p="0.01).">

CONCLUSION: High grade MRI bone oedema was common within the field of intended surgery and associated with pain. There was concordance between the presence and severity of MRI bone oedema and osteitis on histology, with an MRI threshold effect due to differences in image resolution.

PMID: 17491098 [PubMed - as supplied by publisher]