Severity of articular cartilage abnormality in patients with osteoarthritis: evaluation with fast spin-echo MR vs arthroscopy.
OBJECTIVE
The purpose of this study was to assess the accuracy of fast spin-echo MR imaging for depicting the severity of articular cartilage abnormalities in patients with osteoarthritis.


METHODS
Twenty-three subjects (10 volunteers less than 35 years old and 13 patients with proved, symptomatic, idiopathic osteoarthritis of the knee of 6 months' to 10 years' clinical duration) underwent fast spin-echo MR imaging of the knee. Two observers graded each articular surface using a five-category scale that took into account abnormalities in the signal intensity of cartilage as well as thickness and contour. The 13 patients also underwent arthroscopic evaluation (as part of a separate protocol) in which cartilage abnormalities were graded by using a similar five-category grading scale, without the graders knowing the results of MR imaging. Articular cartilage was assumed to be normal in the volunteers.


RESULTS
One hundred thirty-seven joint surfaces were graded; one surface was obscured by artifact and was excluded. The Spearman rank linear correlation between arthroscopic and MR grading was highly significant (p < .002) for each of the six articular regions evaluated. The MR and arthroscopic grades were the same in 93 (68%) of 137 joint surfaces, they were the same or differed by one grade in 123 surfaces (90%), and they were the same or differed by one or two grades in 129 surfaces (94%).


CONCLUSIONS
Our results suggest that fat-presaturated fast spin-echo MR imaging depicts the severity of articular cartilage abnormalities in osteoarthritis with reasonable accuracy, as compared with arthroscopic evaluation as the standard of reference.
Broderick
L S
LS
Department of Diagnostic Radiology and Nuclear Medicine, Rush Medical College and Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60612.
Turner
D A
DA
Renfrew
D L
DL
Schnitzer
T J
TJ
Huff
J P
JP
Harris
C
C
D000328:Adult; D001182:Arthroscopy; D002358:Cartilage, Articular / Q000473:pathology*; D006801:Humans; D007719:Knee Joint / Q000473:pathology; D008279:Magnetic Resonance Imaging; D010003:Osteoarthritis / Q000175:diagnosis*