Blue boxes: popliteal fossa and leg

Question 1

Describe popliteal access and tumors. How do they spread and why?

Answer 1

The spread superior and inferiorly because of the toughness of the popliteal fossa

Question 2

How would you palpate for the popliteal pulse?

Answer 2

Prone position with the knee flexed; go to the inferior part of the fossa

Question 3

Describe a popliteal aneurysm and hemmorage

Answer 3

• caused by edema and pain; can be differentiated due to palpable pulsations and abnormal artery sounds
• may compress the tibial nerve because the artery is deep to it

Question 4

What is a concern given that the popliteal artery and vein are so close in proximity?

Answer 4

Following an aneurysm or a hemorrhage the artery and vein could merge together into an arteriovenous fistula which is emergent

Question 5

Describe an injury to the tibial nerve. How can it occur? What happens if it is severed?

Answer 5

It can occur from the posterior dislocation of the knee joint or deep laceration

A severed tibial nerve can lead to paralysis of the flexor muscles of the leg, intrinsic muscles of the sole of the foot, and an inability of to plantar flex the toes and a loss of sensation in the sole of the foot

Question 6

How does inflammation in the anterior and posterior compartments spread? A lateral infection?

Answer 6

Anterior and posterior: spread distally

Lateral: spread proximally and can go into the popliteal fossa via the fibular nerve

Question 7

Describe the problems that can arise with a compartmental infection in the leg

Answer 7

Since the septum of the leg are strong, it can result in an increase in pressure due to infections

Question 8

Describe shin splints. Why do they occur? What happens to the muscles that are in the anterior compartments?

Answer 8

Results from micro trauma to the tibialis anterior and usually occur secondary to trauma and overuse injuries

The anterior compartment muscles swell which leads to a decreased blood flow to the muscles and tendons secondary to the edema

Question 9

Describe the evolution of the human foot and the fibularis muscle

Answer 9

Feet of higher primates are inverted so that they can walk on the outer border

Humans feet are more inverted so the soles lay on the ground which is secondary to the migration of the fibularis longs muscle across the sole of the foot and the development of the fibularis tertius muscle that is attached to the 5th metatarsal

Question 10

What is the most commonly injured nerve of the lower limb and why?

Answer 10

Common fibular nerve because it wraps around the fibular neck

Question 11

What happens in the event of a severed fibular nerve?

Answer 11

flaccid paralysis of the muscles in the anterior and lateral compartments

Question 12

What happens with an injury to the common fibular nerve?

Answer 12

Loss of dorsiflexion which leads to foot drop; and opposed inversion of the foot with a “clomp” during walking

Question 13

What are the three ways in which people can compensate for a lower limb that is too long ?

Answer 13

1. Waddling gait – individual leans to side opposite long limb
2. Swing-out gait – long limb is abducted to allow toes to clear
3. Steppage gait – extra flexion of the thigh to raise knee as high as necessary

Question 14

Describe deep fibular nerve entrapment, what are two causes? What is another name for the injury?

Answer 14

Excessive use of the anterior compartment which causes edema to the muscles which can compress the nerve

The nerve may become compressed in the inferior extensor retinaculum which leads to pain in the dorsal of the foot

called “ski boot syndrome”

Question 15

Describe superficial nerve entrapment and what causes it

Answer 15

Chronic ankle sprains produce recurrent stretching of this nerve and may cause pain along the lateral side of leg and dorsum of the ankle and foot

Question 16

Who is the fabella?

Answer 16

A sesamoid bone that may be present in the lateral head of the gastrocnemius and articulates with the lateral femoral condyle in 3-5% of people

Question 17

Describe calcañal tendinitis

Answer 17

• Inflammation of the calcaneal tendon happens from microscopic tears of the collagen fibers, particularly just superior to its attachment to the calcaneus
• Usually occurs in individuals who suddenly increase their training, but may also result from poor footwear

Question 18

Describe a ruptures calcaneal tendon

Answer 18

• Usually happens to people with calcaneal tendinitis
• This injury typically happens as an audible snap during push-off (plantarflexion w/knee extended) with a sudden dorsiflexion following immediately
• Most severe muscular problem because individual cannot plantarflex…can only walk when foot is in eversion and without push off
• Obviously, there will be bruising and a lump in the calf bc of shortening of triceps surae

Question 19

What dermatome does the calcneal tendon reflex test?

Answer 19

S1 and S2

Question 20

Which muscles will try to compensate in the absence of plantar flexion? (if the calf muscles are paralyzed or a calcanea tendon is ruptured

Answer 20

gluteus maximus and hamstrings can push off
hamstrings can extend the thigh and the quads can extend the knee

Will rotate the foot as far laterally as possible to disable passive dorsiflexion

Question 21

Describe calcañal bursitis

Answer 21

• Inflammation of the deep bursa of the calcaneal tendon

* Occurs commonly during long distance running, basketball, and tennis

Question 22

When a person is standing, what does the venous return of the leg depend on? how does it work?

Answer 22

It depends on the muscular activity of the triceps surae

Venous plexus that is deep to the the muscles and contraction pumps the blood superiorly

Question 23

Where is the accessory soles?

Answer 23

• Usually appears as a distal belly medial to the calcaneal tendon (3% of people)

Question 24

Where is the posterior tibial pulse?

Answer 24

• Palpated between the posterior surface of medial malleolus and medial border of the calcaneal tendon
• Important to have person invert the foot because the tibial artery is deep to the flexor retinaculum
• Essential for patients with occlusive peripheral artery disease; assess bilaterally
• Absence of pulse is normal in 15% of young people, but is a sign of disease in people older than 60