Pre-Clinical Clerkship

Session 5: Abdominal and Peripheral Vascular Exams

(note to mac users. You may have to manually switch between Male and Female data sets. The pulldown menu is above the right window. Start with the male and switch to the female when instructed.)

This exercise is keyed to your PCC syllabus.

The construction of this lesson is in progress, but you should be able to use the links that are in place to guide your study.

(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.)

Note: The male donor is used in this exercise, solely because the female donor has not been prepared for use in this software. The female pelvis has been completed and we await the advance of this project to include additional regions.

Clinical Anatomical Landmarks

Begin with the skeleton. Key ribs and vertebrae are highlighted. Anterior view ; Posterior view

Key organs and vessels (with full rib cage, with only key ribs): The lungs have been omitted (feel free to add them in) to see the heart better, as you rotate the image. Hint: The image will rotate continuously if you hold the directional arrow on your key board down.

Infer the position of the Midsternal Line, MidClavicular Line, Anterior Axillary Line (add back skin!)

Estimate the inferior lines of pleural reflection from the superior surfaces of the liver and spleen. The subclavian artery is included to help you estimate the superior lines of pleural reflection, as this vessel arcs over the apex of the lungs and pleural cavity. Add and remove skin with the slider to help keep reference to surface landmarks.

Note that the umbilicus of the Male individual is atypically located at L5. The female individual is more typical, with the umbilicus at L3 (just below the subcostal plane). The position of the umbilicus also varies with obese individuals.

The kidneys are percussed at the costovertebral angle between the 12th rib and spine.

The span of the liver is percussed, anteriorly, along the midclavicular line starting at the 4th to 6th ribs (where the lungs are -- right middle lobe) and traveling inferiorly (to roughly 2 cm below the costal margin in a normal individual. The liver edge is palpated along MCL below the costal margin on deep inspiration. (Sorry, we can't show that!)

Castell's point for splenic percussion: 9th LICS at AAL. Note the location of the spleen in the cross-section (if the green plane is not showing in the main window, type ctrl-p; the plane corresponds to the X-section). Look a few sections higher (8th LICS at AAL) . The spleen can push the splenic flexure and fat around to expand anteriorly and then medially. Organs or the body wall block its expansion in other directions. A very large spleen would be palpable where the MCL meets the costal margin.

CT of enlarged spleen (compare to 9th LICS at AAL)

 

Additional Abdominal Pelvic Maneuvers - iliopsoas and obturator signs

These signs are useful to detect free fluid in the abdomen or pelvis. When the patient is in the prone position the posterior body wall is in the dependent position. The excess fluid will pool on top of the psoas muscle in the abdomen or the internal obturator muscle in the pelvis (female example). On the axial image, roll over the levator ani next to the rectum. The attachment of the levator ani divides the internal obturator into pelvic and perineal portionis. The superior/anterior portion of the internal obturator is in the pelvis where fluid would accumulate between the rectum and bladder (male) or the rectouterine pouch of Douglas (female). Because of the lordotic curve of the back, there is a ridge such that fluid will pool either superiorly (cranially) in the abdomen or inferiorly (caudally) in the pelvis, as illustrated below.

The iliopsoas participates in hip flexion. Note its attachment on the lesser trochanter of the femur. Hip flexion and extension will tighten and relax the muscle and the fluid will irritate the over-lying peritoneum in the abdomen.

The internal obturator particpates in hip rotation. Note its attachment on the greater trochanter. Hip internal and external rotation will tighten and relax the muscle and the fluid will irritate the peritoneum over-lying the pelvic portion of the internal obturator.

Abdominal pulses (where to auscultate renal or iliac bruits)

The renal arteries lie approximately in the subcostal plane. A common way of finding the renal arteries is to listen for them 2-cm above the umbilical (or subcostal) plane, but as in this individual, the subcostal plane is more reliable. (Note that the plane selected for the axial image is roughly 2-cm above the subcostal margin)

The iliac arteries course from L4 (plane of iliac crests), or often just below the umbilicus) to the midpoint of the inguinal ligament)

Lower extremity pulses

Popliteal Artery (Tibia is white to help see branches of the artery). Use the axial image to see how deep the artery is. Add in muscles. The image is rotated so that you can see through a gap in the muscles to see the artery.

Posterior tibial artery runs half-way between the medial malleolus and the tip of the calcaneus (left foot in this view, with corresponding axial view).

Dorsalis pedis artery is an extension of the anterior tibial artery and can be palpated between the first two metatarsals (right foot in this view, with corresponding axial view).

©2007 Cheryl Walters, Lawrence Rizzolo, Yale School of Medicine