Patterns of MRI Bone Erosion in Rheumatoid Arthritis – Which Bones Are Most Frequently Involved and Show Most Change?

Mikkel Østergaard1,Uffe Møller Døhn2,Anne Duer-Jensen2,Merete L Hetland, MD, PhD3,Kim Hørslev-Petersen4,Kristian Stengaard-Pedersen, MD, DMSc5,Peter Junker, MD6,Jan Pødenphant7,Bo Ejbjerg8. 1Copenhagen University Hospitals at Hvidovre and Glostrup, Copenhagen, Denmark, Hvidovre,2Copenhagen University Hospitals at Hvidovre and Glostrup, Copenhagen, Denmark,3Rheumatology 232, Copenhagen University Hospitals at Hvidovre and Glostrup, Copenhagen, Denmark, Hvidovre,4KIng Christian X's Rheumatism Hospital, University of Southern Denmark, Gråsten, Denmark,5Rheumatology, Århus University Hospital, Århus, Denmark, Aarhus,6Dept of Internal Med C/Rheum, Odense University Hospital, Odense, Denmark, Odense C,7Copenhagen University Hospitals at Gentofte, Copenhagen, Denmark,8Slagelse Hospital, Denmark

Background: Magnetic resonance imaging (MRI) has been shown to be more sensitive for early bone damage than conventional radiography, and MRI of unilateral wrist and 2nd- 5th metacarpophalangeal (MCP) joints is more sensitive to change for erosive progression than radiography of both hands, wrists and forefeet. However, data on the exact distribution of bone erosions, i.e. the pattern of bone involvement are minimal.

Objective: To investigate which bones in RA wrists and MCP-joints that most frequently show bone erosion and which bones most frequently show erosive progression, in early as well as established RA and during disease-modifying anti-rheumatic drug (DMARD) as well as anti-tumor necrosis factor (TNF) therapy.

Patients and Methods: MRI datasets from 258 RA patients (126 with early RA (disease duration <6 months)) were analysed. 223 patients (126 early RA) had 1-year follow-up MRIs. All patients had MRI of one wrist, whereas 86 had additional MCP-joint images, and 46 had additional images of the contralateral wrist. MRIs were evaluated according to the OMERACT RA MRI scoring system (RAMRIS) for erosions, and presence/absence of erosion at baseline was noted in each bone, as was presence/absence of erosive progression.

Results: The distribution of baseline erosions per wrist bone is shown in Figure 1a, whereas the distribution of bones with progression at year 1 is seen in Figure 1b. The capitate, ulna, lunate, triquetrum and scaphoid were the 5 bones with both most frequent baseline erosion and most frequent erosive progression, whereas metacarpal (M) base 3-4-5 were rarely involved. The patterns were similar in early RA and established RA.
In patients with bilateral wrist MRI available, no apparent major difference between dominant and non-dominant was found (269 versus 277 bones with baseline erosion; 73 versus 85 bones with erosive progression). In the patients in which both wrist and MCP-joint images were available, baseline erosions were still most frequently found in the 5 previously mentioned wrist bones, whereas the 2nd metacarpal head was the most frequently involved MCP-joint bone.



Conclusion: Based on data from 223 RA patients, patterns of MRI bone erosion in RA wrists and MCP joints could be identified. The ulna, scaphoid, lunate, triquetrum and capitate were the most frequently involved bones and showed most change over time. No obvious differences between dominant and non-dominant wrists were identified. Bone involvement patterns should be considered, when joints are selected for MR imaging protocols for clinical trials and practice.

Keywords: magnetic resonance imaging (MRI), rheumatoid arthritis (RA), imaging techniques, MRI, Erosion

Disclosure:

  • Mikkel Østergaard: Nothing to disclose.
  • Uffe Møller Døhn: Nothing to disclose.
  • Anne Duer-Jensen: Nothing to disclose.
  • Merete Hetland:  Nothing to disclose.
  • Kim Hørslev-Petersen:  Nothing to disclose.
  • Kristian Stengaard-Pedersen:  Nothing to disclose.
  • Peter Junker: Nothing to disclose.
  • Jan Pødenphant:  Nothing to disclose.
  • Bo Ejbjerg: Nothing to disclose.