Related Experiment Video
Updated: Jul 6, 2026
Standardized Histomorphometric Evaluation of Osteoarthritis in a Surgical Mouse Model
Published on: May 6, 2020
High-grade MRI bone oedema is common within the surgical field in rheumatoid arthritis patients undergoing joint
F M McQueen1, A Gao, M Ostergaard
1Department of Molecular Medicine and Pathology, Faculty of Medicine and Health Sciences, University of Auckland, Park Rd, Private Bag 92019 Auckland, New Zealand. f.mcqueen@auckland.ac.nz
Objectives:
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:
Preoperative 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:
Inter-reader intraclass correlation coefficients 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 >/=50% maximum) was strongly associated with the surgical field (OR 9.3 (3.5 to 24.2), p<0.0001). Bone oedema scores correlated with pain (r = 0.67, p = 0.048) and CRP (r = 0.86, p = 0.01). In 4 of the 7 bone samples, there was concordance between bone oedema and subchondral osteitis. In 3, there was no MRI bone oedema, and osteitis was "slight".
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.
Insights
High-grade MRI bone oedema is common in rheumatoid arthritis (RA) patients undergoing surgery and correlates with pain. Histopathology confirms MRI findings, revealing bone oedema as a marker for subchondral osteitis.
Area of Science:
- Rheumatology
- Orthopedics
- Radiology
Background:
- Bone oedema on MRI in rheumatoid arthritis (RA) may indicate subchondral osteitis.
- Understanding this relationship is crucial for surgical planning and patient outcomes.
Purpose of the Study:
- To identify regions of bone oedema using MRI in RA patients undergoing surgery.
- To correlate MRI findings with histopathological examination of resected bone.
Main Methods:
- Contrast-enhanced MRI scans were performed on 11 RA patients prior to surgery.
- Bone oedema was scored using the RAMRIS system and analyzed for distribution.
- Histopathological examination of bone samples was compared with MRI findings.
Main Results:
- Bone oedema was more prevalent at surgical sites (60%) than non-surgical sites (38%).
- High-grade bone oedema was strongly associated with the surgical field (OR 9.3, p<0.0001).
- MRI bone oedema showed concordance with subchondral osteitis in 4 of 7 samples.
Conclusions:
- High-grade MRI bone oedema is frequently observed in the surgical field of RA patients.
- A correlation exists between MRI-detected bone oedema and histologically confirmed osteitis.
- MRI bone oedema is a valuable indicator of subchondral osteitis in RA.
