In the radiological grading of rheumatoid arthritis, which Larsen grade indicates the presence of large erosions with extensive destruction of joint architecture while the original bone outline is still partly visible?
- A Grade II
- B Grade III
- C Grade IV ✓
- D Grade V
Correct answer: C. Grade IV
Explanation
In the Larsen grading system for RA, Grade IV (marked abnormality) shows large erosions with partial loss of original bone outline but some architecture preserved. Grade V represents mutilating changes where the original bone outline is completely lost. Grade III (medium abnormality) shows definite erosions with intact bone outline. Grade II shows small erosions. This grading is critical for monitoring disease progression and treatment response.
Reference: Grainger & Allison's Diagnostic Radiology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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