MSK Lower Extremity Best (up to slide 28)

Question 1

Hip Flexors:

Answer 1

L2-3

Question 2

Knee Extensors:

Answer 2

L4

Question 3

Heel Walking:

Answer 3

L4/5

Question 4

Ankle dorsiflexion:

Answer 4

L5

Question 5

Great Toe extension:

Answer 5

L5

Question 6

Walk on Toes/Plantar Flexion =

Answer 6

S1

Question 7

Muscles of the hip:

Answer 7

Question 8

Tendons and ligamentous structures of the hip

Answer 8

Question 9

Anterior tendon and ligamentous structures

Answer 9

• Anterior inferior iliac spine
• greater trochanter of the femur
• pubofemoral ligament
• iliofemoral ligament

Question 10

Posterior tendon and ligamentous structures

Answer 10

Question 11

What happens to the distal fragments in a Femoral Neck Fracture?

Answer 11

• Fragments are acted upon by the muscles.
• Strongest muscles will determine movement of the distal fragments.

Question 12

What changes occur with a hip fx?

Answer 12

rotation and foreshadowing

• if the Pt has fractured the hip:
• their greater trochanter will be externally rotated by the gluteus muscle, and the adductors will pull the distal femur proximally and the adductors will pull also
• you would expect rotation and foreshortening (due to the external rotation of the distal leg in relation to the proximal pelvis)

Question 13

Answer 13

Hip fx-intertrochanteric

Question 14

Avascular necrosis

Answer 14

• Usually seen in the Femoral Head
• Increasingly common, accounts for 10% of Total Hip Replacements
• Femoral Head is an end organ system with poor collateral circulation. Compromise of the arterial supply, especially the Medial Circumflex artery, causes ischemia. This can be seen secondary to:

–Trauma

–Vasculitis

–Vasospasm - decompression

–Circulating microemboli -

• Hemoglobinopathies (Sickle Cell Disease)
• Fat emboli
• Hypercoagulable States
• Decompression Sickness

–Steroid Therapy

–Alcoholism

–Pancreatitis

–Dialysis

Question 15

Where else can avascular necrosis occur? (think hand)

Answer 15

• Similar phenomenon occurs in Scaphoid bone with compromised circulation
• Seen with alcoholism, steroids, Bends, arterial embolism/thrombosis, Sickle Cell Anemia.

Question 16

Describe the blood supply to the femoral head

Answer 16

primarily via the Medial circumflex femoral artery, and to a lesser extent the Lateral Circumflex artery. There is also blood flow via the artery to the Ligamentum teres (a branch of the Obturator artery). Compromise to this latter artery can also lead to Avascular Necrosis of the Femoral Head

Question 17

Thigh: anterior compartment innervation

Answer 17

anterior compartment (Quads) – Femoral Nerve

Question 18

thigh: medial compartment innervation

Answer 18

medial compartment=adductors–> via obturator nerve

Question 19

Thigh: posterior compartment innervation

Answer 19

hamstrings–> via sciatic nerve

Question 20

Leg (lower leg)– Generalizations – Sciatic N to Common Fibular nerve and Tibial Nerve

Answer 20

–Lateral Compartment and innervation – CFN to Superficial Fibular Nerve

–Anterior Compartment and innervation – CFN to Deep Fibular Nerve

Posterior Compartment and innervation – Tibial Nerve

Question 21

Communication Pathways between Pelvis and Lower Extremity (

Note major nerves of the Thigh and what compartments they innervate

See SGT FOS

Answer 21

Question 22

Gluteal Injection Site: what do you want to make sure YOU DONT stick?

Answer 22

• injection site is in the gluteus medius
• Gluteal injection site (you want to make sure you don’t stick the sciatic nerve !!!!!!! You want the upper lateral quadrant of the posterior buttock area

Question 23

Proximal thigh :

• list superficial veins
• list deep veins (what can occur in deep veins?)

Answer 23

superficial veins: Long Saphenous –-medial and superficial, not deep

deep veins – Femoral and Profunda Femoris

**Deep veins (DVT) are where. Dangerous clots occur that break off to cause Pulmonary Emboli

Question 24

Mid thigh

Answer 24

Note Profunda femoris/Deep Femoral artery and vein.

Note Femoral artery and vein.

Note Greater Saphenous vein.

Question 25

Distal thigh: is the entrance to the _____

Answer 25

politeal fossa

• Note veins, both the superficial Long/Greater Saphenous and the Short/Lesser Saphenous veins.
• The deep Popliteal vein.–>DVT occur in the deep veins

Question 26

Biarticular muscles =

-(list ex’s)

Answer 26

•Muscles that cross two joints:

–Sartorius – Flexes hip and flexes knee

–Semitendinosus, Semimembranosus, and Biceps femoris – extend hip and flex knee

–Rectus femoris – flexes hip and extends knee

–Gastrocnemius – flexes knee and plantar flexes ankle

Question 27

Biarticular Muscles of the Lower Extremity

Answer 27

Question 28

Biarticular Muscles of the Lower Extremity: note which 2 muscles DO NOT cross 2 joints

Answer 28

Note: The Plantaris and Popliteus do not cross two joints

-sartorius is another m that helps with movement of the lower extemity

Question 29

which muscles are knee extensors?

Answer 29