Contraction of the erector spinae muscles can produce either unilateral flexion of the spine, or when they are used bilaterally they produce extension of the spine, which is more properly called the vertebral column.
The erector spinae
Erector spinae
Erector spinae
Erector Spinae
a muscle
yes
erector spinae
The erector spinae
Erector Spinae
The erector spinae
Erector Spinae
Rectus Abdominis