Comparative Analysis of Bone Erosions and -Cysts in Rheumatoid Arthritis, Psoriatic Arthritis and Erosive Hand Osteoarthritis

Transcription

1 Comparative Analysis of Bone Erosions and -Cysts in Rheumatoid Arthritis, Psoriatic Arthritis and Erosive Hand Osteoarthritis Stephanie Finzel Department of Internal Medicine 3 Rheumatology & Immunology University of Erlangen-Nuremberg Germany

2 Conflict of Interest No Conflicts of Interest! 2

3 Objectives: Aim of this study: to investigate the differences in the pattern of erosion formation in patients with rheumatoid arthritis (RA), psoriatic arthritis (PSA) and erosive hand osteoarthritis (EHOA) by a high-resolution micro-computed tomography scanner (µct). 3

4 Methods I Altogether 75 patients from our Outpatient Clinic were included into this study: 25 patients with Rheumatoid Arthritis (RA) fulfilling the old and new ACR classification criteria 25 patients with Psoriatic Arthritis (PSA) according to CASPAR classification criteria 25 patients with erosive hand Osteoarthritis (EHOA) Individuals were included age- and gendermatched 4

5 Methods II hrpqct (XtremeCT SCANCO medical AG, Brüttisellen, Switzerland) at a resolution of 82 x 82 x 82 μm voxel size Scan of the metacarpophalangeal joint (MCP) of the clinically more affected hand 5

6 Methods III Scan: 80 slices distal and 242 slices proximal of the upper margin of the third metacarpal head (MCH III) 6

7 Methods IV: Analysis of Erosions Localization, number and severity of bone erosions 24 different joint compartments MCP 2 MCP 3 Erosion: Periarticular cortical break of at least 500 µm MCP 4 7

8 Methods V: Bone Cysts and Joint Spaces MCP 2 MCP 3 MCP 4 Localization and number of bone cysts Bone Cysts: absence of trabecular structure in a circumscript area without cortical break Width of joint spaces 8

9 Methods IV: Scoring system µct Grade 0 Grade 1 Grade 2 Grade 3 Erosion no erosion with a erosion with a destruction of Score evidence cortical break cortical break normal joint (ES) for erosions <1.9mm >1.9mm structure 9

10 Results I: Number and Localization of Erosions Total number of erosions in RA and PSA similar to EHOA Specific distribution pattern of erosions in EHOA: - MCP III and IV show more erosions than in RA - metacarpal heads (MCH) >> phalangeal bases (PB) - involvement of ulnar quadrants >> radial regions EHOA shows a PSA-like pattern of bone erosion 0,9 0,8 0,7 0,6 0,5 0,4 0,3 0,2 0,1 The 4 different quadrants (Q1: palmar; Q2: ulnar, Q3: dorsal, Q4: radial) of each joint compartment were analysed separately. Green bars indicate: EHOA, red bars: PSA, blue bars: RA. Mean Values are shown. 0 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 10

11 Results II: Severity of Erosions Bone erosions in EHOA were less severe as compared to RA MCP 4 more severely affected metacarpal heads (MCH) >> phalangeal bases (PB) severity of erosions in ulnar quadrants >> radial quadrants 0,9 0,8 0,7 0,6 0,5 0,4 0,3 0,2 0,1 0 The 4 different quadrants (Q1: palmar; Q2: ulnar, Q3: dorsal, Q4: radial) of each joint compartment were analysed separately. Green bars indicate: EHOA, red bars: PSA, blue bars: RA. Mean Values are shown. Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 11

12 Example: Pattern and Size of Erosions Image 1: RA wide, U-shaped erosion radial quadrant of MCH II bare area affected Image 2: PSA small cortical break Omega -shaped both MCH and PB affected 12 Image 3: EHOA small cortical breaks irregular linings localized both in subchondral and peripheral regions erosions predomin. ulnar and radial

13 Results III: Distribution Pattern of Bone Cysts Image 1: RA Bone Cysts in 24% of patients Image 2: PSA Bone Cysts in 36% of patients 13 Image 3: EHOA 92% of patients had bone cysts positive correlation of higher age, male sex and postmenopausal state with bone cysts

14 Results IV: Mean Width and Depth of Erosions EHOA RA PSA Mean Width of Erosion (mm) Mean Depth of Erosion (mm) 1,499 2,090 1,397 1,739 2,040 1,604 14

15 JS width (mm) Gelenkspaltweite (mm) width JS (mm) Results V: Comparison of Joint Spaces Joint Spaces (JS) in EHOA are reduced as compared to PSA and Comparison of Joint Spaces RA. 2,10 1,90 1,70 1,50 EHOA: green line PSA: red line Joint Spaces RA RA: blue line Joint Spaces PSA Joint Spaces EHOA Mean Values ± SD. 1,30 1,10 D2 D3 D4 MCP joints 2-4 MCP Gelenke 2-4 MCP joints

16 Results VI: Comparison of joint Young spaces men and women in men and women 2,00 1,80 1,60 1,40 1,20 1,00 0,80 premenopausal women men <45 years of age 0,60 0,40 0,20 0,00 men <45 years of age D2 D3 D4 premenopausal women 16

17 Example: bone alterations and joint spaces in men and women with EHOA 37-year-old woman; joint spaces are intact, bone structure is almost normal 32-year-old male: joint spaces are unaffected, MCP 3 shows a bone cyst 17

18 Results VII: Comparison of joint Aged spaces men and womenin men and women 2,00 1,80 1,60 1,40 1,20 1,00 0,80 postmenopausal women men >45 years of age 0,60 0,40 0,20 0,00 men >45 years of age D2 D3 D4 postmenopausal women 18

19 Example: bone alterations and joint spaces in men and women with EHOA 62-year-old woman; joint spaces are slightly reduced, small cysts in PB and MCH 3; subchondral erosive lesion in MCH3 62-year-old male: MCPs 2+3 show distinct bone cysts, erosions and joint space narrowing 19

20 Summary: High-resolution µct imaging shows profound differences in periarticular bone changes between RA, PSA and EHOA. Our data indicate that it is possible to differentiate between inflammatory- and degeneratively triggered erosion formation by advanced imaging technology. This suggests different mechanisms to be involved in bone remodeling in RA, PSA and EHOA. 20

21 Acknowledgements Department of Internal Medicine 3, University Clinic of Erlangen-Nuremberg: Barbara Herz, Sarah Schmidt, Christian Ernet Jürgen Rech, Matthias Englbrecht Jochen Zwerina, Christian Stach Georg Schett 21