Postfracture instability of vertebrae with simulated defects can be predicted from computed tomography data.
METHODS
Structural properties of vertebrae with simulated defects were measured from computed tomography data. Relations between structural properties and postfracture stability were tested using linear regressions.


OBJECTIVE
To determine whether the postfracture stability of lumbar and thoracic vertebrae can be predicted from noninvasive, prefracture measurements of structural properties.


BACKGROUND
Sensitive and specific guidelines are needed that can predict fracture risk and spinal stability after pathologic fractures. Such guidelines may help determine whether treatment is needed to prevent neurologic complications. Simple measurements made from computed tomography data can predict the load-bearing capacity of intact vertebrae and vertebrae with simulated and actual metastatic defects. It is not known whether these same measurements can also predict postfracture stability.


METHODS
Simulated metastatic defects were created in human three-vertebrae segments from the lumbar and thoracic spine. Axial rigidity was calculated from quantitative computed tomography data, and failure load and postfracture stability were measured.


RESULTS
Postfracture stability was linearly correlated with both failure load (r2 = 0.3-0.6) and axial rigidity (r2 = 0.3-0.6).


CONCLUSIONS
The postfracture stability of three-vertebrae segments with simulated defects was modestly related to noninvasively measured, prefracture structural properties.
Windhagen
H
H
Department of Orthopedic Surgery, Hannover Medical School, Hannover Germany.
Hipp
J A
JA
Hayes
W C
WC
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D016014:Linear Models; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000293:injuries / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016059:Range of Motion, Articular; D016103:Spinal Fractures / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D013125:Spinal Neoplasms / Q000150:complications / Q000556:secondary; D013314:Stress, Mechanical; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging* / Q000293:injuries / Q000503:physiopathology; D014057:Tomography, X-Ray Computed