[MRI evaluation of the patellar articular cartilage in patients with subluxation of the patella].
In patients with subluxation of the patella, injury of the patellar articular cartilage is frequently observed and correct evaluation is important to manage these patients. We examined 11 patients with subluxation of the patella and five normal volunteers. In 12 patellofemoral joints of seven patients with subluxation of the patella, the abnormalities observed on MRI were compared with those on arthroscopy and/or at operation. MRI was performed with a Magnetom 1.5 T (Siemens) using the round surface coil. Pulse sequences were SE (TR 400 ms/TE 19 ms), FLASH (TR 320 ms/TE 15 ms FA 90 degrees and 40 degrees), and SE (TR 2000 ms/TE 26, 70 ms). We analysed MR findings of the 12 abnormal joints and 10 normal joints according to the following classification of abnormalities observed on arthroscopy. (1) normal appearance (n = 3 joints), (2) softening and fibrillation (n = 6), (3) fragmentation (n = 3), and (4) erosion to bone (n = 0). In only one of the six cases with softening and fibrillation observed on arthroscopy, MRI could visualize the thickening of patellar articular cartilage, but in all three cases with fragmentation observed on arthroscopy, MRI could visualize the thin inhomogenous cartilage with irregular surface. The combination of SE (TR 400 ms/TE 19 ms) and FLASH (TR 320 ms/TE 15 ms FA 90 degrees) are extremely effective pulse sequence to detect the abnormalities of patellar articular cartilage. We conclude that MRI is a useful noninvasive method of detecting advanced changes in patellar articular cartilage.
Nakanishi
K
K
Department of Radiology, Osaka University Medical School.
Inoue
M
M
Harada
K
K
Murakami
T
T
Kim
S
S
Fujita
N
N
Sakurai
K
K
Kozuka
T
T
D000293:Adolescent; D000328:Adult; D002358:Cartilage, Articular / Q000473:pathology*; D002648:Child; D005260:Female; D006801:Humans; D004204:Joint Dislocations / Q000175:diagnosis*; D007718:Knee Injuries / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging; D008297:Male; D010329:Patella / Q000293:injuries*