MRCS Part B (OSCE) - Online Resources

"

• The psoas major originates along the lateral surfaces of the vertebral bodies of T12 and L1-L5 and their associated intervertebral discs.
• The iliacus originates in the iliac fossa of the pelvis.
• Psoas major unites with the iliacus at the level of the inguinal ligament and crosses the hip joint to insert on the lesser trochanter of the femur.

"

"The iliopsoas acts conjointly to flex and laterally rotate the hip joint. If the limb is fixed, it helps in flexion of the trunk. "

"

• The mid-inguinal point is halfway between the pubic symphysis and the anterior superior iliac spine.
• The femoral artery crosses into the lower limb and can be palpated at this anatomical landmark.

"

The femoral sheath is a shaped fascial tube, the femoral sheath, extends 3-4 cm inferior to the inguinal ligament and encloses the proximal parts of the femoral vessels and the femoral canal. It is a continuation of the transversalis fascia anteriorly and the iliopsoas fascia posteriorly. The sheath ends by becoming continuous with the adventitia covering the femoral vessels. It allows the femoral vessels to glide deep to the inguinal ligament during movement of the hip.

 

The femoral sheath encloses the proximal parts of the femoral artery, femoral vein and femoral canal. The femoral sheath does not enclose the femoral nerve.

 

The femoral sheath is subdivided into three compartments (lateral, intermediate and medial) by vertical septa which are derived from extra-peritoneal connective tissue of the abdomen that extends along the vessels. The femoral canal is the medial compartment of the femoral sheath. The femoral canal allows the femoral vein to expand during increased venous return of the lower limb.

 

The femoral canal contains fat, lymphatics and Cloquet’s node.

Cloquet’s node drains the lower limb, perineum and anterior abdominal inferior to the umbilicus. It may be enlarged in cases of carcinoma or infection at these sites.

The base of the femoral canal (the abdominal end) is directed superiorly and, although oval-shaped, is called the ‘femoral ring’.

 

 Anterior : Inguinal ligament.
 Posterior : Pectineal ligament.
 Medial : Lacunar ligament.
 Lateral : Femoral vein.

 

Femoral hernias can enter the thigh through the femoral ring. They may present as a tender mass in the femoral triangle, infero-lateral to the pubic tubercle. The hernia is bounded by the femoral vein laterally and the lacunar ligament medially.

 

• The external iliac artery becomes the common femoral artery at the level of the inguinal ligament (mid-inguinal point).
• Approximately 4 cm into the femoral triangle, the common femoral artery divides into the deep profunda femoris artery and the superficial femoral artery.
• The profunda femoris artery gives off the medial and lateral circumflex femoral arteries.
• The superficial femoral artery runs to the apex of the femoral triangle, enters the adductor canal and exits the adductor hiatus to form the popliteal artery.