A&P 106: Chapter 8 - Appendicular Skeleton
What is the only bone in the ankle that articulates with the tibia and the fibula?
Talus The talus is the only bone in the ankle that articulates with the tibia and the fibula. The transmission of force from the weight of the body proceeds from the tibia through the talus and to the toes. The articulation of the talus and the fibula is through the lateral surfaces of both bones. This connection functions to stabilize the ankle. The calcaneus makes up the heel bone and does not articulate with the tibia or the fibula. The navicular and cuboid do not articulate with the tibia or the fibula.
What is the name of the large, concave socket that articulates with the head of the femur?
Acetabulum The acetabulum is the name of the large, concave socket that articulates with the head of the femur. The coxal bone and femur form a very stable ball-and-socket joint. This socket is formed from the three fused bones of the coxa: the ilium, the ischium, and the pubis. The obturator foramen is an opening between the pubis and the ischium. The iliac fossa is a depression in the ilium. The greater sciatic notch does not articulate with the femur.
Which part of the foot provides a cushioning or shock-absorbing effect?
The longitudinal arch Ligaments and tendons maintain the longitudinal arch by tying the calcaneus to the distal portions of the metatarsal bones. The lateral or calcaneal portion of the arch has much less curvature than the medial or talar portion of the arch. The talar portion has more elasticity. The elasticity of the talar portion absorbs shock from sudden changes in weight loading. This springiness helps distribute the weight over the whole foot and thus has a cushioning effect.
The appendicular skeleton has many long bones. Which of the following is NOT characteristic of long bones? a. They are as long as they are wide. b. They have epiphyses. c. They have a diaphysis. d. Many have a head joined to a neck that would articulate with another bone.
a. They are as long as they are wide. Each long bone shares common features with other long bones. They have a proximal and distal epiphysis. They have a diaphysis called a shaft. However, they are much longer than they are wide.
Which of the following is found on the distal portion of the humerus? a. trochlea b. head c. surgical neck d. greater tubercle
a. trochlea The trochlea is the medial aspect of the distal end of the humerus. This is a grooved area in the condyle that articulates with the trochlear notch of the ulna. The head, surgical neck and the greater tubercle are part of the proximal end of the humerus.
The surfaces of the scapulae and clavicles are extremely important as sites for __________.
muscle attachment The surfaces of the scapulae and clavicles are extremely important as sites for muscle attachment. The scapulae and clavicles articulate with the humerus at the shoulder joint, which is one of the most unstable synovial joints in the body. Many of these attachment sites serve the group of muscles known as the rotator cuff. This group of muscles stabilizes the humerus in the shoulder joint. The surfaces of the scapulae and clavicles are not important as sites for the positions of nerves and blood vessels, nourishment of muscles and bones, and support and flexibility.
A prominent ridge that runs across the posterior surface of the scapula is __________.
the scapular spine The acromion is continuous with the scapular spine, a prominent ridge that crosses the posterior surface of the scapular body before ending at the medial border. The spine is an important landmark and an attachment site for muscles of the shoulder and posterior neck.
The large medial bone of the leg is the ____________.
tibia The large medial bone of the lower leg is the tibia. The tibia is responsible for transferring the weight of the body to the ankles and feet. The distal end of the tibia forms the medial malleolus.
The small, pea-shaped pisiform bone sits anterior to the __________ bone.
triquetrum The small, pea-shaped pisiform bone sits anterior to the triquetrum bone. This carpal bone is classified as a proximal carpal bone due to its distance from the shoulder and torso. This is in contrast to the distal carpal bones, which are closer to the phalanges.
Which of the following is the largest and heaviest bone in the body?
Femur The femur is the largest and heaviest bone in the body. This is a classic long bone with a shaft known as the diaphysis, the region that houses the medullary cavity, which contains red and yellow marrow. The proximal and distal ends of the femur are known as epiphyses. These regions contain the epiphyseal plates, which allow long bone growth to occur and increase height during maturation. The humerus is the largest upper limb bone. The tibia is the largest bone of the lower leg. The sternum is a flat bone on the axial skeleton.
The body of the scapula is valuable for what reason?
It is the attachment site for muscles that move the arm. The anterior and posterior surfaces of the scapula are muscle attachment sites for muscles that move the arm. The posterior surface is marked with small ridges and lines where smaller muscles attach. The anterior surface of the body is smooth and concave. This depression is called the subscapular fossa. This fossa is where one muscle attaches to move the arm.
What is the prominent ridge that runs along the center of the posterior surface of the femur and serves as an attachment site for muscles that adduct the femur?
Linea aspera The linea aspera is the prominent ridge that runs along the center of the posterior surface of the femur and serves as an attachment site for the muscles that adduct the femur.This landmark is an area of increased surface area and serves to attach tendon to muscle. The fibula is the lateral bone of the lower leg. The patella is also known as the kneecap. The calcaneus forms the heel bone.
Which feature of the ulna forms the point of the elbow?
Olecranon The olecranon is the part of the ulna that forms the elbow. This structure forms a projection known as the olecranon process, that slides into the olecranon fossa in the humerus. This articulation enables flexion and extension at the elbow, which is a hinge joint. The coronoid process is the inferior lip of the trochlear notch. The styloid process is at the distal end of the ulna. The radial notch is inferior to the elbow articulation.
The superior lip of the trochlear notch of the ulna is formed by the __________.
Olecranon The superior lip of the trochlear notch of the ulna is formed by the olecranon. The olecranon is a bony projection also known as the elbow. The inferior lip of the trochlear notch is formed from the coronoid process. The trochlea of the humerus articulates with the ulna to form the elbow joint. The styloid process is on the radius. The ulnar tuberosity does not form the lip of the trochlear notch.
What is the large sesamoid bone found in the tendon of the quadriceps femoris?
Patella The patella is the large sesamoid bone found in the tendon of the quadriceps femoris. This bone is also known as the kneecap. The patella, along with the tibia and the femur, form articulations at the knee joint. The patellar ligament connects the patella to the tibia inferiorly while the patellar tendon connects the patella with the quadriceps femoris.
What structural characteristics of the shoulder joint allow for a great deal of movement?
Relatively weak joint Since the shoulder joint is a relatively weak joint, its range of movement is much more extensive. Joint stability and range of movement are two qualities that are inversely related, so as one increases, the other decreases. For a joint to have a near maximum range of movement, the strength and stability of the joint has to be compromised. Dense bones and strong ligaments will not increase range of movement.
Which bone articulates with the humerus to form the shoulder joint?
Scapula The humerus articulates with the scapula at the glenoid cavity to form the shoulder joint. This joint is also known as the glenohumeral joint, which is reinforced and stabilized by various ligaments and muscles. The ulna and radius form the bones of the forearm. The hamate is one of the carpal bones.
The condyle of the humerus is made up of which structures?
The capitulum and the trochlea At the distal end of the humerus is the articular surface called the condyle. At the condyle, the humerus articulates with the radius and ulna, the bones of the forearm. The condyle is divided into two articular regions: the trochlea and the capitulum. The trochlea is the spool-shaped medial portion and the capitulum is the lateral rounded portion.
When a person fractures the fibula, why does walking become difficult?
The fibula provides lateral stability to the ankle joint. The fibula provides lateral stability to the ankle joint. Unlike the tibia, the fibula does not transfer weight to the feet. However, the fibula does form a stabilizing structure in the ankle joint known as the lateral malleolus. This bone is an important attachment site for muscles that move the feet and toes. The fibula does not transfer weight to the ankle joint. The fibula creates the lateral aspect of the ankle joint and is not part of the knee joint.
Why is it NOT possible to move the bones of the leg like you can move the bones of the forearm, even though there are two bones in each?
The joints and connective tissue between the tibia and fibula are different than the joints and connective tissue between the radius and ulna. The joints and connective tissue between the tibia and fibula are different than the joints and connective tissue between the radius and ulna, which is why it is NOT possible to move the bones of the leg like you can move the bones of the forearm, even though there are two bones in each. The head of the tibia articulates with the articular facet on the anterior inferior surface of the lateral tibial condyle. However, this joint is not a freely moveable joint. The medial border of the thin shaft of the fibula is bound to the tibia by the interosseous membrane, which extends to the lateral margin of the tibia. This membrane stabilizes the position of the two bones but restricts movement between the tibia and fibula.
Which of the following would occur if you broke your collarbone?
The stability of the scapula would decrease. The clavicles stabilize the position of the scapula. When you move the scapula, you can feel the sternal end of the clavicle move. The clavicle limits the movement of the scapula. If you broke the clavicle, the mobility of the scapula would increase but the stability would decrease. The scapula and arm could still move, but the scapula would not be as stable.
What is the unusual compromise of the articulations in the appendicular skeleton?
The stronger the joint, the more restricted the range of motion. The stronger the joint, the more restricted the range of motion. With regard to joints, mobility and stability are mutually exclusive. In order to increase the stability of a joint, movement must be restricted. On the other hand, if mobility is to be increased, stability must be sacrificed to enable a greater range of motion. "The weaker the joint, the more restricted the range of motion" is false since restricting motion stabilizes a joint. "The stronger the joint, the less restricted the range of motion" is false since a stronger joint will have less motion associated with it. "The strength of the joint and the range of motion are unrelated" is false since they are inversely related.
The trochlea of the humerus articulates with what bone?
Ulna The trochlea of the humerus articulates with ulna. This articulation of the trochlea is with the trochlear notch of the ulna. This articulation forms the medial portion of the elbow joint. The lateral portion of this joint is formed between the humerus and radius. The radius articulates with the capitulum of the humerus. The scapula and the clavicle do not articulate with the humerus.
Which of the following is NOT a feature of the femur? a. Lateral malleolus b. Patellar surface c. Linea aspera b. Greater trochanter
a. Lateral malleolus The lateral malleolus is NOT a feature of the femur but is a part of the fibula, which is the smaller of the lower leg bones. This bone does not actually support any weight and mainly functions to stabilize the ankle. Like the forearm, the fibula and the tibia are bound together by an interosseous membrane. The greater trochanter is a large projection at the proximal end of the femur. The linea aspera is a roughened ridge on the diaphysis of the femur. The patellar surface is on the anterior and inferior surface of the femur.
Which of the following features, found on the tibia and fibula, provide(s) support for the ankle joint? a. Malleoli b. Trochanter c. Condyle d. Tuberosity
a. Malleoli The malleoli are found on the tibia and fibula and provide support for the ankle joint. The malleoli are projections from the distal ends of the tibia and fibula that articulate with the tarsal bones. A tuberosity is a rounded projection. A condyle is a rounded protuberance. A trochanter is a bony protuberance of the femur.
Compared to the axial skeleton, which of the following is not a function of the appendicular skeleton? a. Protecting abdominal and thoracic organs b. Allowing movement from place to place c. Taking notes in a lecture class d. Texting a friend with a cell phone
a. Protecting abdominal and thoracic organs The appendicular skeleton is composed of the bones of the appendages and the girdles that attach the appendages to the body. Think of all the things you do with your arms and legs: standing, walking, writing, turning pages, dressing, shaking hands, and texting. It is the axial skeleton that protects thoracic and abdominal organs.
Which of the following changes in the skeleton does not happen from the time of birth to young adulthood? a. Reduction of the mineral content of the bony matrix b. development of the major curves of the vertebral column c. closure of the fontanelles d. fusion of the epiphyseal cartilages to form epiphyseal line
a. Reduction of the mineral content of the bony matrix Beginning at age 30-45, there is gradual reduction in the mineral content of the bony matrix. This can lead to osteoporosis and a greater risk of fractures. Generally, people are protected from mineral loss during the early years of life.
Which of the following is a common difference between the male and female skeleton? a. The mandible is larger and more robust in males. b. The cranium is larger in the female skeleton. c. Teeth are larger in the female. d. The pelvic girdle is narrower in the female.
a. The mandible is larger and more robust in males. Because testosterone has a stronger stimulatory effect on bone growth than does estrogen, it is very common for males to have greater bone mass and density. On average, males may grow taller. They have thicker bones and more muscle mass attached to the bones. This will apply to the mandible, which, in males, is larger and more robust.
Which of the following statements is most accurate comparing the differences in male and female pelvic girdle? a. The pelvic inlet in the female is more open and circular. b. The pubic angle in the female pelvis is less than 90 degrees. c. The female ilium is more vertical. d. The female sacrum is more curved.
a. The pelvic inlet in the female is more open and circular. The female pelvis is adapted to childbirth. The ilium bones are less vertical. That makes the female pelvic inlet more open and circular. The pelvic outlet is larger. This will allow the baby to be passed through the pelvic girdle more easily. The adaptations of the female pelvis also help support the weight of the baby during pregnancy.
Which of the following tarsals forms the bone of the heel? a. calcaneus b. talus c. medial cuneiform d. cuboid
a. calcaneus The calcaneus is the tarsal bone that forms the heel of the foot. This bone is a major area of mechanical impact during walking and running. This bone also connects to the gastrocnemius (calf muscle) through the calcaneal tendon, which is also known as the Achilles tendon. The talus is the tarsal bone that articulates with the tibia. The medial cuneiform is an anterior tarsal bone. The cuboid articulates with the calcaneus.
Which of the following is commonly known as the collarbone? a. clavicle b. sternum c. ulna d. scapula
a. clavicle The clavicle is also known as the collarbone. These curved bones connect medially to the manubrium and laterally to the scapula. With the scapula, the clavicle forms the pectoral girdle. This girdle forms a scaffold from which the upper and lower arms can hang. The scapula is also known as the shoulder blades. The ulna is a bone of the forearm. The sternum is also known as the breastbone.
Which of the following is NOT one of the three fused bones that form each coxal bone? a. coccyx b. pubis c. ischium d. ilium
a. coccyx The coccyx is NOT one of the bones that fuse to form the coxal bones. The coxal bones are formed from three bones fused together: the ilium, the ischium, and the pubis. The coxae are major scaffolding in the lower torso that serves to protect the abdominopelvic organs. These bones also serve as major attachment sites for muscles and connective tissue.
What rough area of the ilium marks the site of articulation with the sacrum?
auricular surface Auricular surface is the rough area which marks the site of articulation between the ilium and the sacrum. These two bones form the sacroiliac joint, which functions as an absorber of shock during walking. This articulation has some movement but mainly functions to ensure stability of the pelve. Anterior gluteal line is not an articular surface. Ischial tuberosity is an inferior projection at the bottom of the pelvis. Iliac crest is at the most superior ridge of the ilium.
Which body region is NOT included in the appendicular skeleton? a. pelvis b. head c. leg d. arm
b. head The head is NOT a part of the appendicular skeleton. Rather, it is a component of the axial skeleton. The head forms the most superior part of the axial skeleton, with the vertebral column, ribs, and sternum forming the rest of this part of the skeleton.
The general appearance of the female pelvis is different from that of the male pelvis in that the female pelvis is __________.
broad, light, and smooth The general appearance of the female pelvis is different from that of the male pelvis in that the female pelvis is broad, light, and smooth. Since the female pelvis is designed for childbearing, the pelvis is broad and has more space within its structure than the male pelvis. This greater amount of space helps accommodate the expansion seen during pregnancy and the growth of the fetus. A robust, heavy, and rough appearance is seen in the male pelvis. "Relatively deep" and "Heart shaped" are not features of the female pelvis.
Which of the following is NOT a feature of the scapula? a. coracoid process b. spine c. trochlea d. acromion
c. trochlea The trochlea is NOT a part of the scapula; instead, it is a structure found in the distal part of the humerus. The trochlea is a medial aspect of the condyle. This grooved portion of the humerus articulates with the trochlear notch of the ulna. The acromion and the coracoid process are bony projections of the scapula. The spine is a posterior aspect of the scapula.
What is the name for the heel bone?
calcaneus The ankle consists of seven tarsal bones. The calcaneus or the heel bone is the largest of the tarsal bones. When you stand normally, most of the weight is transmitted from the tibia to the talus, then to the calcaneus, and then to the ground. The posterior portion is a roughened process to which the calcaneal tendon from the calf muscles is attached.
The largest carpal bone in the hand is the __________.
capitate The capitate is the largest of the carpal bones. This bone is among the distal carpal bones of the hand and sits between the trapezoid and hamate. The capitate is superior to metacarpal III.
Which bone provides the only fixed support for the pectoral girdle?
clavicle The clavicle provides the only fixed support to the pectoral girdle. The clavicle, together with the scapula, form the pectoral girdle, which is also known as the shoulder girdle. The joint formed by these two bones is known as the acromioclavicular joint and forms this V-shaped structure. In contrast to the scapula, the clavicle forms a joint at its sternal end with the manubrium of the sternum. Scapula has no articulation other than with the clavicle. The pelvis is not a part of the pectoral girdle. The acetabulum is a part of the pelvis.
The bones of the pectoral girdle include the __________.
clavicle and scapula The bones of the pectoral girdle include the clavicle and scapula. The pectoral girdle is also known as the shoulder girdle. This girdle, along with the humerus, form the shoulder joint, which is one of the most unstable synovial joints in the body. This structure provides an area of articulation for the humerus and the bones of the pectoral girdle The ilium and ischium are components of the coxal bones. The humerus and scapula do not form the pectoral girdle. The ulna and radius are bones that make up the forearm.
The only joint between the upper appendage and the axial skeleton involves which bones?
clavicle and sternum The medial anterior end of each scapula articulates with the manubrium of the sternum. These articulations are the only direct connection between the pectoral girdles and the axial skeleton. Skeletal muscles support the scapula, which has no direct bony or ligamentous connections to the thoracic cage.
Which of the following data could be determined by studying the bones of a skeleton? a. The person's sex b. The person's muscular development c. The person's age d. All of the listed responses are correct.
d. All of the listed responses are correct. All of the listed responses are correct. A person's age may be deduced from such things as the relative density of the bones, the ossification of cartilaginous regions, the reduction in size of bone markings, etc. Muscular development may be deduced from the density of bone since bone density increases with mechanical stresses. Sex may be determined from the relative size and shape of the skull and pelvis.
The head of the ulna is located __________ to the ulnar tuberosity.
distal
When someone is told they have a "broken hip" or a hip fracture, what bone is actually broken?
femur A hip fracture actually involves the femur and not a hipbone. The two types of hip fractures are femoral neck fractures and intertrochanteric fractures. In a femoral neck fracture, the femoral head is separated from the femur and its blood supply. There is no disconnection from the blood supply in an intertrochanteric fracture. As a result, such fractures may be repaired with a metal plate and screws.
What bone articulates, or forms a joint, with the acetabulum?
femur The femur forms a joint with the acetabulum. The acetabulum is a socket in the coxae that articulates with the head of the femur. Together, these two bones form the hip joint. This is a ball-and-socket joint like the shoulder joint. However, in contrast to the shoulder joint, the hip joint is formed from an actual socket in the coxae, which makes this a much more stable joint than the shoulder joint. The humerus is the largest upper arm bone. The pubis is part of the acetabulum. The tibia is a lower leg bone.
The term "phalanges" is used for the bones of the __________.
fingers and toes The term "phalanges" is used for the bones of the fingers and toes. The phalanges are among the smallest bones of the appendicular skeleton and are the most distal bones of the body. The thumb and big toe have their own names, the pollex and the hallux, respectively. Bones of the wrist are referred to by the term "carpals." Bones of the toes and the fingers are referred to by the term "phalanges."
What is the term given to the big toe?
hallux Hallux is the term for the big toe. This toe is the most medial and contains only a proximal and a distal phalanx. This is in contrast to the other toes, each of which has three phalanges. "Pollex" is the term for the thumb. A talus is a tarsal bone. A pisiform is a carpal bone.
The more superior, broad, and wing-like bone of the pelvic girdle is the __________.
ilium The ilium, ischium, and pubis are fused together to form the coxal bones. The ilium forms a broad curved surface that provides an extensive area for the attachment of muscles. This bone is the most superior of the three bones.
The enlarged roughened projection that bears your weight when you are sitting is the __________.
ischial tuberosity The ischial tuberosity is a roughened projection located at the posterior and lateral edge of the ischium. When you are sitting, it bears your body weight. This process is the origin for the hamstring muscles of the posterior thigh.
The malleolus of the fibula is always on the __________ aspect of the leg.
lateral The malleolus of the fibula is always on the lateral aspect of the leg. A malleolus is a projection from a long bone, either the tibia or the fibula, in the lower leg. The medial malleoulus is part of the tibia. Together, these two bony projections make up what are commonly known as the ankles.
Weight transfer occurs along the __________ of the foot.
longitudinal arch Weight transfer occurs along the longitudinal arch of the foot. This arch is a framework of bones, tendons and ligaments which provides some elastic rebound associated with the landing of the feet on the ground. This arch also enables blood vessels and nerves on the inferior surface of the foot to remain uncompressed. The linea aspera is a landmark along the shaft of the femur. The calcaneus is also known as the heel bone. The hallux is also known as the big toe.
The clavicles articulate with a bone of the sternum called the __________.
manubrium The clavicles articulate with a bone of the sternum called the manubrium. This bone is the most superior portion of the sternum, above the sternal body and xiphoid process. The clavicles articulate with the manubrium at their sternal end, which is the most medial edge of the clavicle.
Which part of the scapula is closest to the vertebral column?
medial border The scapula is a triangle-shaped bone. The three sides are the superior border, the medial border, and the lateral border. The medial border, sometimes called the vertebral border, is closest to the vertebral column. In fact there are muscles that originate on the vertebrae that move the scapula.
Which bones form the palm of the hand?
metacarpals The metacarpals form the palm of the hand. These bones are identified with Roman numerals and are numbered I - V starting laterally. Distally the metacarpals articulate with the proximal phalanges, while proximally the metacarpals articulate with the distal carpal bones. Metatarsals form the sole of the foot. Phalanges are the bones of the fingers and toes. Carpals are the bones of the wrist.
What is the structure that joins the femoral head to the shaft?
neck The neck is the structure that joins the femoral head to the shaft. The neck is a short, angular structure and is one of the main sites of hip fractures. When the neck is fractured, the femoral head is separated from the femur itself. The linea aspera is a landmark along the shaft of the femur. The lateral condyle is distal to the neck. The greater trochanter is inferior to the neck.
What structure do the scapula and the clavicle make up?
pectoral girdle Each arm articulates with the trunk at a pectoral girdle or shoulder girdle. The pectoral girdle consists of an S-shaped clavicle and a broad irregularly shaped scapula.
The primary function of the pectoral girdle is to __________.
position the shoulder joint and provide a base for arm movement The primary function of the pectoral girdle is to position the shoulder joint and provide a base for arm movement. The pectoral girdle is also known as the shoulder girdle. This area articulates with the humerus to form the shoulder joint, which is the most unstable joint of the body as well as the most mobile. The primary function of this girdle is not to provide areas for articulation with the verbal column, protect the organs of the thorax, or support and maintain the position of the skull.
The olecranon fossa on the humerus is located on the bone's __________ surface.
posterior The olecranon fossa on the humerus is located on the bone's posterior surface. This is a depression in the surface of the humerus that accommodates the articulation with the olecranon on the ulna during extension at the elbow joint.
The spine of the scapula is located on the bone's __________ surface.
posterior The spine of the scapula is located on the bone's posterior surface. This spine is a major landmark on the scapula and serves as an attachment site for muscles associated with the rotator cuff. The scapular spine is not located on the anterior, medial, or the lateral side.
The bones of the forearm are the __________.
radius and the ulna The bones of the forearm are the radius and the ulna. These two bones are stabilized in position by connective tissue known as the interosseous membrane. When the hand is in anatomic position, with the palm facing anteriorly, these two bones are parallel. When the hand is rotated medially, these two bones cross each other. This rotation is known as pronation. the humerus is in the upper arm and the clavicle forms part of the pectoral girdle
At its proximal end, the round head of the humerus articulates with the __________.
scapula At its proximal end, the round head of the humerus articulates with the scapula. This articulation with the scapula occurs at the glenoid cavity. This joint is the glenohumeral joint, also known as the shoulder joint. It has the greatest range of motion compared to all other joints in the body. This also means the shoulder joint is the most unstable joint in the body. The radius does not articulate with the humerus at the proximal end. The clavicle does not articulate with the humerus.
The coracoid process and acromion are parts of the __________.
scapula The coracoid process and acromion are parts of the scapula. These are scapular processes which extend beyond the border of the glenoid cavity. The smaller anterior projection is the coracoid process. The acromion is the larger, posterior process. The acromion articulates with the clavicle at the acromioclavicular joint. Both of these processes are attached to ligaments and tendons associated with the shoulder joint.
Which bone has a glenoid cavity that is the site of articulation with the humerus in the pectoral girdle?
scapula The scapula has a glenoid cavity that is the site of articulation with the humerus in the pectoral girdle. The scapula connects with the lateral aspect of the clavicle to form the pectoral girdle, which is also known as the shoulder girdle.
Which two bones articulate at the glenoid cavity?
scapula and humerus The lateral margin of the scapula supports a cup-shaped structure called the glenoid cavity. At the glenoid cavity, the scapula articulates with the humerus, the proximal bone of the upper limb. This articulation, also known as the glenohumeral joint, is the shoulder joint.
What attaches the scapula to the trunk of the body?
skeletal muscle The medial anterior end of each clavicle articulates with the manubrium of the sternum. These articulations are the only direct connections between the pectoral girdles and the axial skeleton. Thus, there are no bony connections between the scapula and the trunk. Skeletal muscles support and position the scapula on the thoracic cage.
On the clavicle, the __________ articulates with the manubrium.
sternal end On the clavicle, the sternal end articulates with the manubrium. This connection also serves as a meeting point between the axial and the appendicular divisions of the human skeleton in the upper torso. The clavicle, which is also known as the collarbone, forms the pectoral girdle as it articulates with the scapula laterally. The conoid tubercle and coracoid process do not articulate with the manubrium. The acromial end of the clavicle articulates with the scapula.
The bony point of the shoulder that you feel along the superior margin of the shoulder joint is __________.
the acromion process Two large scapular processes extend beyond the margin of the glenoid cavity superior to the head of the humerus. The smaller projection is the coracoid process. The acromion or acromion process is the large posterior process. If you run your fingers along the superior surface of the shoulder joint, you will feel this process.
As a group, the metatarsals are the bones that comprise __________.
the arch of the foot The metatarsals are five long bones that form the distal portion of the foot, or metatarsus. They form most of the arch of the foot. The metatarsal bones are identified by Roman numerals I-V, proceeding from medial to lateral. In their role as the arch of the foot, they articulate proximally with the cuneiform tarsals and the cuboid, and distally with the phalanges.
The sacrum and the coccyx are curved in __________.
the male pelvis The sacrum and the coccyx are curved in the male pelvis. Since the male pelvis is not designed for childbearing, the volume within this bony structure is much smaller than that within the female pelvis. In contrast, the female pelvis has the sacrum and coccyx pointed inferiorly. The female pelvis is much broader and curved, which also creates more space within the structure. The female pelvis does not have a curved sacrum and coccyx.
What structures limit the extension of the forearm?
the olecranon and the olecranan fossa The olecranon forms the superior lip of the trochlear notch. The trochlear notch fits onto the trochlea. This forms part of the elbow joint. At the limit of extension, movement that straightens the forearm and arm, the olecranon swings into the olecranon fossa on the posterior surface of the humerus.
The joint between the two coxal bones is called the __________.
the pubic symphysis The anterior and medial surface of the pubis has a roughened area at the site of articulation with the pubis on the opposite side. This articulation is the pubic symphysis. The two pubic bones are attached to a median pad of fibrocartilage.
The pollex is the __________.
thumb The pollex is also known as the thumb. This digit is the only one which has two phalanges instead of three as is seen with the rest of the fingers. This digit is also the only place in the body where you will see a saddle joint. The elbow is the olecranon. The heel bone is also known as the calcaneus. The big toe is also known as the hallux.
The large medial bone of the leg is the ____________.
tibia The large medial bone of the lower leg is the tibia. The tibia is responsible for transferring the weight of the body to the ankles and feet. The distal end of the tibia forms the medial malleolus. The fibula is the smaller of the two lower leg bones. The femur is the largest and heaviest bone in the body. The humerus is the largest upper limb bone.
The distal carpals are the __________.
trapezium, trapezoid, capitate, hamate These bones, which make up part of the wrist, are immediately superior to the metacarpal bones that make up the palm of the hand. The proximal carpal bones are the scaphoid, lunate, triquetrum, and pisiform. The trapezium, scaphoid, trapezoid, and lunate, capitate, triquetrum, and hamate are not all distal carpals.
What bony processes are unique to the femur and are found at the junction of the neck and shaft of the femur?
trochanters The greater and lesser trochanters are large rough processes that originate at the junction of the neck and the shaft of the femur. The greater trochanter projects laterally. The lesser trochanter projects posteriorly and medially. They are muscle attachment sites.
