Popliteal Artery Bypass Procedure
(At any time you can rotate the image or add or subtract structures. Clicking the link will always bring you back to a starting point. Remember to use rollovers to see the labels for the various structures. Also, by moving the axial plane to any point in the image on the right, you can see the cross-section on the lower left. Any coloration in the right image will be shown in the cross-sections.)
Be sure to add or remove skin as needed to confirm
your orientation. Explore the
preset images by rotating them or adjusting the plane of section. To enhance the 3D quality of the image,
use the control (PC) or command (Mac) keys
plus the right and left arrows to rotate the image back and forth.
In this case, the vessel to
be bypassed is the femoral
artery. Note its location in the adductor canal. Rotate the image 180 degrees to see it
enter the popliteal fossa.
First consider the physical
exam. Part of the diagnosis
involved palpating the femoral, popliteal, and tibial
or dorsal pulses. The femoral
pulse is found inferior to the inguinal ligament; observe how it is close
to the skin. The popliteal pulse is found in the popliteal
fossa where the popliteal artery is very deep. Notice how deep it is on the
axial section and by restoring the skin. Try to palpate it with
your knee extended. It is difficult
to feel because all the tissue is taught.
Instead, bend the knee and feel how soft the tissue becomes. That is because the fossa is mostly fat,
as can be seen on the axial section. The posterior tibial pulse is easily palpated halfway between the
medial malleolus and the posterior end of the calcaneal bone. The dorsalis pedis
pulse is palpated between the first two metatarsals.
In our case, the patient had
a strong femoral pulse, but the popliteal and tibial and
dorsalis pedis pulses were
absent. Together with imaging studies, these findings indicate stenosis along
the course of the femoral artery.
The first step in the
procedure is to tie-off the common femoral artery near the
inguinal ligament both proximal and distal to the site of the bypass
graft. It is also necessary to tie-off
the deep femoral artery.
Anasomotic connections about the hip would
allow blood to flow into the graft site via the deep femoral artery. Note the close proximity of the femoral nerve, femoral vein
and lymph nodes. Rotate the image back and forth to
appreciate how superficial some of the nodes are.
The second step would be to
tie-off the graft site of the popliteal artery. Access to the artery is gained via the
medial side of the knee.