The Lower Extremities

The pelvic girdle is made of two bones, the os coxae (sing. - os coxa) or hip bones. Each os coxa is formed from three embryonic bones. These are the large, superior ilium, the posterior, inferior ischium, and the anterior, inferior pubis. The three embryonic bones fuse to form a single os coxa.

The os coxa has several important bone markings. The large fossa in the os coxa is the acetabulum which articulates with the femur of the leg. The obturator foramen is between the pubis and the ischium. The sciatic notch is located on the ilium. The superior ridge of the ilium is the iliac crest.

Femur DiagramFemur Diagram
Figure 11.2 Right Hand

Capitate (X2) Carpus Hamate (X2) Lunate (X2) Trapezium (X2) Trapezoid (X2) Triquetrum (X2)

Metacarpal V Phalanges Pisiform (X2) Scaphoid (X2) 84

Figure 11.3 Os Coxa, Lateral Aspect

Acetabulum Iliac crest Ilium Ischium Obturator foramen Pubis Symphysis pubis Sciatic notch

The upper leg bone is the femur. The head of the femur is a rounded projection which articulates with the acetabulum of the os coxa. Lateral to the head is a large, blunt projection, the greater trochanter, which serves as a site for muscle attachment.

At the distal end of the femur are two projections, the lateral condyle and the medial condyle. Projecting from each condyle is an epicondyle, the lateral and medial epicondyles.

Articulating with the distal end of the femur is the tibia. The tibia has a lateral condyle and a medial condyle which articulate with the corresponding condyles of the femur. Distal to the condyles of the tibia and on the anterior surface is the tibial tuberosity, another site of muscle attachment. At the distal end of the tibia is a prominent, medial projection, the medial malleolus which holds the foot in position.

Label Distal Medial Head Femur
Figure 11.4 Lower Extremeties

Femur Fibula Head of femur Head of fibula Greater trochanter Ilium Ischium Lateral condyle of femur Lateral condyle of tibia Lateral epicondyle Lateral malleolus Medial condyle of femur Medial condyle of tibia Medial epicondyle Medial malleolus Patella Pubis Talus Tibia Tibial tuberosity

Anterior to the joint formed by the femur and the tibia is a sesamoid bone, the patella. The knee joint is made of these three bones: femur, tibia, and patella.

The smaller of the lower leg bones is the fibula. This bone does not articulate with the femur. Instead, the head of the fibula articulates with the tibia, distal to the lateral condyle of the tibia. The distal end of the fibula has a lateral malleolus which prevents the bones of the foot from sliding laterally.

There are three groups of bones in the foot: the tarsus, the metatarsus, and the phalanges. There are seven tarsals in each tarsus. (Recall that there were eight carpals in the wrist!) The superior tarsal is the talus. This is the only bone of the foot which articulates with the tibia and the fibula. The heel bone is the calcaneus. Anterior to the talus is the navicular. Anterior to the calcaneus is the cuboid. The final tarsals are the three cuneiforms which are medial to the cuboid and distal to the navicular. The cuneiforms are named first, second, and third from the medial side. A mnemonic phrase to aid in memory of the tarsals is "Charles III Never Climbs Tall Curbs." There are three cuneiforms, a navicular, cuboid, calcaneus, and a talus. The phrase does not deal with the bones in any particular order.

Distal to the tarsals are the five metatarsals. The metatarsals are numbered from the big toe, so metatarsal I is medial and metatarsal V is lateral. Note that the metacarpals are numbered from the thumb, so metacarpal I is lateral. This is a difference between the upper and lower extremities.

Attached to the metatarsals are the fourteen phalanges. Like the thumb, the big toe has only two phalanges. All other toes have three phalanges: proximal, middle, and distal.

Exercise 11.2

It is interesting to count the number of bones in the hands and feet. There are phalanges in each hand and foot for a total of_phalanges. Counting both hands and both feet there are a total of_carpals, metacarpals, tarsals, and metatarsals. Thus, the total number of bones in the hands and feet together is_, more than in the rest of the body put together!

SUPERIOR

SUPERIOR

Labeing Bones Phalanges
Figure 11.5 Right Foot

Calcaneus Cuboid Cuneiforms Metatarsals Navicular Phalanges Talus Tarsus

1. Label all of the bones on the diagram

Practice Labeling Bone Markings

3. __The head of the humerus articulates the (3) of the scapula.

4. __The head of the femur articulates with the (4) of the hip bone.

5. __The head of the ulna is (proximal/distal).

6. __The head of the radius articulates with the (6) of the humerus and the (7) of the ulna.

8. __True or false. The head of the fibula joins the femur at the knee.

9. __Which tarsal joins the tibia?

10. __Which tarsal joins the fibula?

11. __Which bone of the extremities is located within a tendon?

12. __How many carpals are there?

13. __True or false. The thumb is attached to metacarpal V.

14. __Which bone process is the elbow?

15. __Which fossa articulates with the trochlea?

16. __Which bone process fits into the coronoid fossa?

17. __On which bone is this process (#16) located?

18. __On which bone is the coronoid fossa located?

19. __What is the purpose of the greater trochanter?

20. __Describe the exact location of the greater trochanter.

21. __Which muscle attaches to the deltoid tuberosity?

22. __On which bone would you find the deltoid tuberosity?

24. __How many bones are in a tarsus?

25. __How is the name of the upper arm bone correctly spelled?

26. __In alphabetical order list the two bones of a shoulder girdle.

28. __The collar bone articulates with the (28) of the scapula.

29. __The ridge of bone at the back of the shoulder is the (29) .

30. _ Name the process anterior and superior to the glenoid cavity of the scapula.

32. _ The two processes which hold the bones of the wrist are the

33. _ Collectively the bones of the wrist are known as the (33) .

34. _ True or false. The fingers have three phalanges, while the thumb has two.

35. _ True or false. Unlike the fingers, all the toes have only two phalanges.

37. _ Name the large hole in the os coxa.

38. _ Name the ridge of bone at the hip.

39. _ Which bone of the axial skeleton articulates with the os coxae?

40. _ Which part of the ox coxa articulates with the other os coxa?

41. _ Which two processes prevent lateral and medial movement of the talus?

42. _ The sciatic nerve travels through a groove on the ilium.

What is the name of the groove?

43. _ Name the distal row of carpals from lateral to medial.

47. __How many phalanges are there in the entire body?

48. __What is the singular of the word "phalanges?"

49. __The capitulum articulates with the (49) of the radius.

50. __The olecranon of the (50) articulates with the (51) of the humerus.

52. __What is the purpose of the tibial tuberosity?

CHAPTER I Z-

Essentials of Human Physiology

Essentials of Human Physiology

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Responses

  • keegan
    Is the femur condyle at the distal end of the tibia?
    7 years ago
  • ritva
    What fibula marking articulates with the tibia?
    6 years ago
  • ambrosia
    What is the name of the distal medial process of femur?
    6 years ago
  • Tuomas
    Where are the greater trochanter and iliac crest located (hat bones)?
    6 years ago
  • milen filmon
    Where is the lateral malleolus of the femur?
    6 years ago
  • Tiffany
    Which part of the ox coxae articulates with the other os coxa?
    6 years ago
  • paula
    What is the ilium vs. iliac fossa?
    6 years ago
  • sebastian
    Which muscle attaches to the condyles of the femur?
    6 years ago
  • nuguse
    How many metatarsals are in the lower an upper extremities?
    5 years ago
  • minto brandybuck
    What is guws medial info?
    5 years ago
  • aili
    What feature of the ox coxa forms a joint with the femur?
    5 years ago
  • hana
    What is objective lower extremity of human bones?
    3 years ago

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