Can you diagnose for vertebral fracture correctly by plain X-ray?
BACKGROUND
A wrong diagnosis of latent vertebral fracture is often made when it is based on plain X-ray imaging. Magnetic resonance imaging (MRI) has a high degree of accuracy for the definite diagnosis. This study was designed to identify ways to support improvements in the diagnostic accuracy of plain X-ray (X-P).


METHODS
We studied X-P and MRI images of 120 women and men (age range: 50-96 years). Five orthopedists and two radiologists interpreted front and lateral thoracolumbar X-Ps and MRI images. The correct diagnosis rate for the presence and location of incident vertebral fractures and the correct diagnosis rate according to morphological classifications were analyzed.


RESULTS
A correct diagnosis of incident fractures was made in 51.5% of cases overall. Diagnoses of non-incident fracture based on X-P in those cases with incident fracture based on MRI (false positive) occurred in 24.8% of the patients, while diagnoses of incident fracture based on X-P in those cases without incident fracture based on MRI (false negative) occurred in 6.5% of the patients. The application of morphological classifications (the primary osteoporosis diagnostic criteria and Yoshida's classification) resulted in the correct diagnosis rate being significantly higher in the group without prevalent fracture even when there were morphological changes (wedge, indented, protruding type) in the anterior bone cortex. Odds ratios were investigated for factors that would affect the correct diagnosis rate, including age, body weight, lumbar vertebrae bone mineral density, and examiner ability. In an overall investigation, age (OR=0.660), body weight (OR=2.082), and examiner ability (p=0.0205) affected the correct diagnosis rate.


CONCLUSIONS
The correct diagnosis rate for incident vertebral fractures with X-Ps was low (24.8%) and in cases with prevalent fractures, the rate was even lower (16.8%), but the number of prevalent fractures and BMD did not exert an effect. One key improving the correct diagnosis rate may be to pay attention to morphological changes in the anterior bone cortex.
Ito
Z
Z
Department of Orthopedic Surgery, National Center for Geriatrics and Gerontology, 36-3 Gengo Morioka-cho, Obu, Japan. z.ito@med.nagoya-u.ac.jp
Harada
A
A
Matsui
Y
Y
Takemura
M
M
Wakao
N
N
Suzuki
T
T
Nihashi
T
T
Kawatsu
S
S
Shimokata
H
H
Ishiguro
N
N
D000368:Aged; D000369:Aged, 80 and over; D001827:Body Height; D001835:Body Weight; D015519:Bone Density; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010024:Osteoporosis / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D011859:Radiography; D016103:Spinal Fractures / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000209:etiology