Characteristics of lumbar scoliosis in patients with rheumatoid arthritis.
BACKGROUND
Although a substantial percentage of patients with rheumatoid arthritis (RA) experience low back pain, the characteristics of lumbar spine pathology in RA patients has been poorly investigated. In our institutions, lumbar spine radiographs indicated scoliosis in 26 patients. The present study aimed to clarify the characteristics of lumbar scoliosis in RA patients.


METHODS
This is a retrospective study of 26 RA patients with lumbar scoliosis. Patient characteristics such as disease duration, disease stage and class according to Steinbrocker's classification, and medication for RA and osteoporosis were reviewed. Radiologic evaluation of scoliosis was performed at two different time points by measuring Cobb angles. The progression of scoliosis per year was calculated by dividing the change in Cobb angles by the number of years. Apical vertebral rotation, lateral listhesis, and the level of the intercrestal line at the first observation were also measured. The correlation between different factors and changes in the Cobb angles per year was analyzed.


RESULTS
Majority of the patients had a long disease duration and were classified as stage 3 or 4 according to Steinbrocker's classification. During the observation period, most patients were treated with glucocorticoids. Unlike the previous studies on degenerative scoliosis, apical vertebral rotation, lateral listhesis, and the level of the intercrestal line at initial observation were not significantly related to the progression of scoliosis. Initial Cobb angles were inversely related to the progression of scoliosis. Patients who were treated with bisphosphonates showed slower progression of scoliosis.


CONCLUSIONS
Our results indicate that the characteristics of lumbar scoliosis in RA patients differ from those of degenerative lumbar scoliosis. Bone fragility due to the long disease duration, poor control of disease activity, and osteoporosis is possibly related to its progression.
Department of Orthopaedic Surgery, Faculty of Medical Sciences, Graduate School of Medicine, Kyushu University, 3-1-1 Maidashi Higashiku, Fukuoka 812-8582, Japan. mohishi@ortho.med.kyushu-u.ac.jp.
Masanobu
M
Ohishi
Hisaaki
H
Miyahara
Masakazu
M
Kondo
Yasuharu
Y
Nakashima
Kazumasa
K
Terada
Yukio
Y
Esaki
Nobuo
N
Kobara
Katsumi
K
Harimaya
Yoshihiro
Y
Matsumoto
Yukihide
Y
Iwamoto
D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012189:Retrospective Studies; D012600:Scoliosis / Q000000981:diagnostic imaging* / Q000453:epidemiology*