Measurement of Cervical Spinal Cord Pressure Using Artificial Cord

Cho, Tai Hyoung; Kwon, Teak Hyun; Park, Jung Yul; Chung, Yong Gu; Suh, Jung Keun; Lee, Hoon Kap

Abstract

It has long been thought that in individuals with congenitally narrower spinal canals, the risk of spinal cord injury might be increased. The purpose of the present study was to quantitatively assess spinal cord pressures in cadaveric human cervical spines with narrow and wide canals, and with normal and degenerative columns. Twelve human cadaveric cervical spine preparations were evaluated on the basis of their level of degeneration and canal size. A drop mass assembly was constructed with different combinations of masses to produce 24 possible drop combinations for each spine preparation. These resulted in input energies from 100 to 1000 'gram-centimeters'. Cadaver cervical spine was instrumented with a collagen encased artificial spinal cord and seven sensor transducer arrays recorded pressures on the cord during the impact event. The results indicated that depending on the extent and and level of degeneration, degenerated spinal columns produced distinctly different patterns of cord pressure. Normal spinal columns produced consistent patterns of high pressures under the impact site, but this decreased caudally and cranially. In specimens with narrow spinal canals, cord pressures under the impact site were significantly higher than in specimens with wide canals. For the higher drop energies(800 and 1000 'g-cm') the disparity between narrow and wide canal specimens increased. This implies that for the same inpt drop energy, the propensity for spinal cord injury is higher for narrower spinal canals than for those which are wider.