Question

5. Compare and contrast lumbar curvature and waist to hip ratio specifically in terms of the research. Where is the research lacking? Where are there good point? (Evolutionary biology course PLZ answer it in a broad and clear way. Thank you!) Expert Answer

Answer 1

Wedging in the lumbar vertebrae extends the tailbone relative to the rest of the spine. This results in acute angle between the thoracic back and buttocks. Lumbar curvature and waist to hip ratio are the characteristics that evolved to create obligate bipedalism.

The higher waist to hip ratio i.e., WHR equal to or greater than 0.85 cause increase lumbar lordosis and sacrum slant angle. This may result in lower back pain. The lumbar curvature and waist to hip ration are therefore related. The research indicated that the waist circumference alone does not contribute to the deviation in lumber angle; however, the higher waist to hip ratio has close association with lumbar lordosis.

Lumbar curvature and WHR are important factors for the effective weight bearing, efficiency of para-spinal muscles, and maintaining erect posture. Changes in lumbar curvature such as hypo or hyper lordosis can increase the load on facet joint and disc, increase the compression of nerve root, degeneration of disc and facet joints, contracture of para-spinal muscle and sprain of para -spinal ligaments.