Now, on the posterior side, you find, as well, another line, letâs say, but this time called the intertrochanteric crest that is also between the neck of the femur and the shaft and runs, as well, from the greater trochanter all the way down to the lesser trochanter.
The upper back has the most structural support, with the ribs attached firmly to each level of the thoracic spine and very limited movement. The lower back (lumbar vertebrae) allows for flexibility and movement in back bending (extension) and forward bending (flexion).
The twelve thoracic vertebrae are numbered T1 to T12. The range of motion in the thoracic spine is limited. Lumbar (low back) - the main function of the lumbar spine is to bear the weight of the body. The five lumbar vertebrae are numbered L1 to L5.