Clinical Cases: Limbs

Question 1

Explain the arterial occlusive disease of the leg: intermittent claudication

Answer 1

-ischemia of the muscles produces a cramp like pain with exercise. Patient is forced to stop walking after a limited distance because of the intensity of the pain. With rest the pain re-occurs

• femoral artery: thigh and calf
• popliteal artery: calf, ankle and foot

Question 2

What is the collateral for the proximal part of the femoral artery?

Answer 2

Through the Cruciate and trochanteric anastomosis

Question 3

How can the femoral artery in the adductor canal be bypassed?

Answer 3

The femoral artery in the adductor canal can be bypassed by perforating branches of the deep femoral artery, descending branch of the lateral femoral circumflex and the Articular and muscular branches of the popliteal arteries

Question 4

What are pelvic fractures?

Answer 4

Commonly result from “high energy” trauma (motor vehicle collisions, falls). These fractures have significant associated morbidity and mortality arising from 1) complications of the fractures themselves, and 2) commonly associated injuries (such as head injuries, etc. that can also occur in high energy trauma)

Except in small children (high elasticity of bones/ligaments), single fractures/ligamentous disruptions of the bony pelvis are uncommon- imagine trying to break a pretzel in one place

Question 5

How deadly is a pelvic fracture?

Answer 5

Morbidity and mortality from the fractures themselves makes it important to recognize the injuries and patterns of injuries, so that appropriate treatments can be implemented earlier rather than later

Question 6

What is pelvic hemorrhage?

Answer 6

Is the most serious immediate complication of a pelvic ring fractures-pelvic veins and/or arteries are disrupted is as many as 3/4 of patients

Venous bleeding arises from disruptions of the pelvic venous plexus or from the marrow space of broken bones

Arterial bleeding occurs when there is direct injury as arterial branches pass close to a bony injury (typically branches of the internal iliac artery- such as the gluteal arteries as they travel near the greater sc8aatic foramen)

Question 7

What are the main mechanisms for pelvic ring fractures?

Answer 7

1. Anterior-posterior compression

2. Lateral compression

Question 8

Explain anterior posterior compression of the pelvic ring

Answer 8

Most commonly result from head on motor vehicle collisions (can also occur with motorcycle collisions or when pedestrians are struck by a vehicle)

Initially, the pubic symphysis is disrupted (either through the fibrocartilage fibers or through a rim of pubic bone on one side or the other

The hemipelvis (one or both) is externally rotated (opened up like a book) - when sufficient force is present, the sacrotuberous and sacrospinous ligaments are disrupted

Question 9

Explain lateral compression of the pelvic ring

Answer 9

Result from side impact such as pedestrian vs vehicle or side impact motor vehicle collisions

The sacrum “buckles” (impacted fracture-typically on the side where the force is applied) and the pubic rami fracture (one side or both) as the hemipelvis is forcefully rotated internally

Question 10

Describe distal femoral fractures

Answer 10

• Seen in high velocity collisions
• Pain and inability to bear weight
• Risk of compartment syndrome

Question 11

Summarize blood supply to the knee

Answer 11

5 genicular arteries from popliteal artery

• Superior medial genicular artery
• Superior lateral genicular artery
• Inferior medial genicular artery
• Inferior lateral genicular artery
• Middle genicular artery

Reccurent branch of anterior tibial artery

Two descendant genicular arteries

• One from femoral artery
• One from the lateral circumflex