Fig. 2. A tracing of a sagittal X-radiograph of the lower thoracic and lumbosacral
spine (excised, unloaded, ligamentous) of a 2.34 kg male Macaca
fascicularis. In contrast to the in vivo dorsal curve during
sitting (see Figs 1 and
3), here the lumbosacral spine
is hyper-extended. P, S, L and T indicate the pelvis and the sacral, lumbar
and thoracic vertebrae, respectively. The length of the lumbar column (L1-L6)
is approximately 10cm. The calculation in this study focuses on the lumbar
column; the angles between these unloaded lumbar intervertebral joints were
estimated by measuring the angles between lines drawn parallel to the long
axes of the vertebral centra.
