There are four abdominal muscles in the
External Oblique, Internal Oblique, Transversus abdominis, and the
It is the large and outermost abdominal muscle you will first see in
dissection. Its fibers are running obliquely downward, hence the name. It is
covered anteriorly by the
Latissimus Dorsi. Origin, on the ribs and in the lumbodorsal fasica,
Insertion, aponeurosis that passes through the linea alba, Action, constrictor
of the abdomen.
The Internal Oblique are just below the External Oblique. Origin, second
sheet of the lumbodorsal fascia and the pelvic girdle. Insertion, linea alba,
Action, compressor of the abdomen.
This muscle is the innermost abdominal muscle. Origin, second sheet of the
lumbodorsal fascia and the pelvic girdle. Insertion, linea alba, Action,
compressor of the abdomen.
To see this muscle, first remove the extensive aponeurosis sitruated on the
ventral suface of the cat. Its fibers are extremely longitudinal, on each side
of the linea alba. It is also traversed by the inscriptiones tendinae, or
what others call myosepta.