Ex Vivo Comparative Study On Lumbar Spine Disc Height And Curvature Between Axially-loaded MSCT And Conventional MSCT Scanning

ObjectiveTo study the function of axially-loaded MSCT scanning, and analyse the value of this method in the diagnostic of slipped lumbar intervertebarl disc using a compression device, by comparing lumbar spine disc height and intervertebral angle of spine healthy volunteers.Method16 volunteers, age 21-32 years , firstly were examined by conventional CT scanning, and then ,they were axially compressed with a force equivalent to 50% of body weight. Original data then were re-constructed, acquiring MPR images. Middle sagitta images were selected to measure intervertebral angle and disc height. Lay out all the results and the statistical meathod used was paired t test.ResultEach intervertebral angle in conventional CT scanning and in axially loaded CT scanning was as follows: L1/2 0.7±0.4 degree and 3.3±2.9 degree;L2/3 4.7±3.5 degree and. 3±6.0 degree;L3/4 7.9±2.4degree and 11.1±4.6 degree;L4/5 14.3±3.3 degree and 14.9±1.7 degree;L5/S1 25.8±5.2 degree and 20.8±6.0 degree。A significant difference between values in conventional CT scanning and axially loaded CT scanning was obtained at L3-L4 and L5-S1. Each disc height in conventional and axially loaded CT scanning was as follows: L1/2 9.05±0.86mm and 8.36±0.28mm;L2/3 9.0±0.96mm and 8.45±0.88mm;L3/4 8.96±0.83mm and 8.26±0.55mm ; L4/5 8.69±1.07mm and 5.95±0.93mm;L5/S1 9.86±0.81mm and 8.53±0.97mm。There was a significant decrease in disc height only at L4-5 during compression.ConclusionAxially-loaded CT scanning on spine healthy volunteers, intervertebral angles changed a lot in L3/4 and L5/S1, disc height changed significantly in L4/5, reflecting disc height and curvature changes in compression, can simulate the upright lumbar spine alignment.