Roux et al developed a score for predicting vertebral fractures in postmenopausal women with osteoporosis and back pain. This can help identify women who should have imaging studies of the spine performed. The authors are from the Universite Paris-Descartes.
Patient selection: postmenopausal woman with osteoporosis and back pain
Parameters:
(1) age
(2) intensity of the back pain (on a 10 cm visual analogue scale, VAS)
(3) loss of height in centimeters
(4) history of non-vertebral fractures (pelvis, forearm, rib, hip)after low-impact trauma
(5) sudden onset of pain
(6) pain localized to thoracic spine
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Parameter
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Finding
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Points
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age of the patient in years
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< 65 years
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0
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|
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65 - 69 years
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1
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|
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70 - 74 years
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2
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|
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75 - 79 years
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3
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|
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>= 80 years
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4
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back pain intensity
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moderate to severe or worse (>= 6.5 cm on VAS)
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2
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less than moderate to severe (< 6.5 cm on VAS)
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0
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loss in height
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< 3 cm
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0
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3 to 5.99 cm
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2
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>= 6 cm
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4
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history of nonvertebral fracture after low impact
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no
|
0
|
|
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yes
|
1
|
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sudden onset of pain
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no
|
0
|
|
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yes
|
4
|
|
pain localized to thoracic spine
|
no
|
0
|
|
|
yes
|
1
|
total score =
= SUM(points for all 6 parameters)
Interpretation:
• minimum score: 0
• maximum score: 16
• The higher the score the greater the chance of a vertebral fracture.
• A score >= 7 is associated with a vertebral fracture in 43% of patients.
• A score <= 2 is associated with a vertebral fracture in < 20% of patients.
Performance:
• The area under to ROC curve is 0.77.
• The positive predictive value is 71% and the negative predictive value is 69%.
Alternatively a logistic regression formula can be used (see pages 83-84):
X =
= (0.0734 * (age in years)) + (0.6129 if pain >= 6.5 cm on VAS) + (0.6622 if height loss 3 to 5.99 cm) + (1.1723 if height loss >= 6 cm) + (0.4793 if history of low impact fractures) + (0.4852 with thoracic localization of pain) + (1.2146 for suddon pain onset) - 7.1082
probability of an osteoporotic vertebral fracture =
= 1 / (1 + EXP((-1) * X))
