Radiological features of lumbar spinal lesions in patients with rheumatoid arthritis with special reference to the changes around intervertebral discs.
BACKGROUND
Compared with the cervical spine, little attention has been paid to rheumatoid arthritis (RA)-related lumbar disorders. Only a few articles have described the status of the lumbar spine affected by RA based on plain X-ray films and magnetic resonance imaging (MRI).


OBJECTIVE
To describe the features and prevalence of radiological changes of the lumbar spine of patients with RA and to clarify the correlations of such features with disease activity.


METHODS
Transverse radiological study.


METHODS
We radiographically examined 104 patients with RA whose age ranged from 21 to 78 years (mean, 51.0). In each, the duration of RA exceeded 10 years (mean, 17.7 years).


METHODS
Clinical outcomes included Ochi's classification, Lansbury index, C-reactive protein (CRP) (mg/dL), rheumatoid factor (RF) (U/mL), and platelet (count/mm). Radiological outcomes included radiography and MRI.


METHODS
One hundred four RA patients were included in this study regardless of the presence/absence of low back pain. We examined discs from L1-2 to L5-S, including endplates, in each patient on plain X-ray films and magnetic resonance images and used a comprehensive grading system to evaluate each feature of the lumbar spine affected by RA based on the present findings and published reports. The correlations of these radiological features with RA activity and Ochi's classification were examined. To quantify disease activity, we determined the Lansbury index, serum CRP (mg/dL), RF (U/mL), and platelet count (count/mm) at the time of radiological examinations.


RESULTS
Of the 104 patients, 47 (45.2%) exhibited a lumbar lesion. There were two types of lumbar disc lesions related to RA: disc narrowing and disc ballooning. The Lansbury index of patients with the most severe lesions was significantly higher than that of patients with less severe lesions (p<.01). The frequency of lumbar involvement also increased as the number of affected peripheral joints increased, and Ochi's classification appeared to be useful in predicting the occurrence of lumbar lesions.


CONCLUSIONS
Of 104 patients, 47 (45.2%) exhibited abnormalities on X-ray films and MRI. There were two types of disorders, disc narrowing and disc ballooning. Both the Lansbury index and Ochi's classification reflected the severity of lumbar lesions in RA patients.
Sakai
Toshinori
T
Department of Orthopedics, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15 Kuramoto, Tokushima 770-8503, Japan.
Sairyo
Koichi
K
Hamada
Daisuke
D
Higashino
Kosaku
K
Katoh
Shinsuke
S
Takata
Yoichiro
Y
Shinomiya
Fumio
F
Yasui
Natsuo
N
D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging* / Q000473:pathology; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012720:Severity of Illness Index; D013130:Spinal Stenosis / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology