Skeletal System (Excluding Axial) Flashcards

1
Q

What bones articulate with the calcaneous?

A

The Cuboid and Talus

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2
Q

What are the bones of the feet?

A

Talus, Calcaneous, Navicular, medial-intermediate-lateral Cunieform, Cuboid, Metatarpals (1-5), Proximal-Intermediate-Distal Phalanx (no intermediate for big toe).

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3
Q

What bones does the Tibia articulate with?

A

DISTALLY- the talus via the talocrural joint
PROXIMALLY- the femur via the lateral and medial condyles of the femur
LATERALLY- Fibula attaches to the proximal/distal-lateral aspect of the Tibia via the proximal & distal tibiofibular joints.

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4
Q

How do you differentiate between the left and right Tibia if handed nothing but the two bones?

A
  1. Look for the proximal end by locating the LATERAL & MEDIAL CONDYLES (femur articulation) and the intercondular eminence (flat spot between the two condyles).
  2. Distinguish anterior vs posterior by looking for the TIBIAL TUBEROSITY (bony prominence where patellar ligaments attach) on the proximal anterior surface, or ANTERIOR CREST (anterior surface of the tibia).
  3. Locate the MEDIAL MALLEOLOUS (a point out of the distal end of the tibia will distinguish medial side of bone).
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5
Q

What purpose does the fibula serve?

A

To maintain alignment of the tibia

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6
Q

What is the function of the tibia?

A

To accept and distribute the weight from the knee to the ankle

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7
Q

What is the soleal line?

A

A visible line found on the posterior tibia, moving in a distal -> medial direction on the proximal 3rd of the tibia.

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8
Q

What bones articulate with the Cuboid?

A

Calcaneous, lateral cuneiform, 4th and 5th metatarsal

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9
Q

Where does the head of the femur join the hip?

A

At the Lunate Articular Surface of the Acetabulum of the hip

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10
Q

How can you differentiate between the anterior and posterior surface of the femur?

A

The Linea Aspera runs along the posterior length of the shaft of the femur

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11
Q

Why is the neck of the femur important?

A

Connects the head and shaft of the femur

Most of the blood supply to the head of the femur runs along the neck (injury can lead to avascular necrosis)

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12
Q

What is the longest bone in the body?

A

The Femur

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13
Q

What bones do the 1st, 2nd, & 3rd metatarpals articulate?

A

1- Medial Cuneiuform & Proximal Phalanx of 1st digit
2- Intermediate Cuneiform & Proximal Phalanx of the 2 digit
3- Lateral Cuneiform & Proximal Phalanx of 3 digit

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14
Q

What is the Fovea Capitis?

A

A small ‘dimple’ found on the head of the femur, where the ligamentum teres resides.

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15
Q

What projections are found at the proximal surface of the shaft extending upwards near the neck of the femur?

A

The Greater and Lesser Tochanter.

greater is closer to the head

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16
Q

Where is the Gluteal Tuberosity?

A

Proximal, posterior part of shaft of femur.

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17
Q

What are the projections at the distal end of the femur?

A

Lateral epicondyle is on the lateral side of the femus, the condyle is posterior.
Same with the medial (epi)condyles.

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18
Q

How do you determine the left from the right femur?

A
  1. Find Linea Aspera (indicates posterior femur)

2. Head of the femur points medially

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19
Q

Where is the Lateral malleoulous found?

A

The lateral, distal surface of the fibula

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20
Q

What is the tibial tuberosity?

A

The anterior bony prominence on the proximal surface of the tibia.
The origin of the Tibialis anterior muscle.

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21
Q

What is the anterior crest?

A

The thin, bony prominence, found anteriorly, that moves from the base of the tibial tuberosity down the length of the shaft.

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22
Q

What is the interosseous membrane?

A

Found between Tibia and Fibula / Radius and Ulna

-a fibrous network membrane that attaches the bones and adds some rigidity.

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23
Q

What are the 3 regions of the hip?

A

Ilium (superior, largest), Ischium (lateral, inferior), Pubis (Medial, inferior)

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24
Q

What is the anterior part of the Iliac crest?

A

The anterior superior iliac spine (ASIS).

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25
What is the greater sciatic notch?
Large indentation, within the ilium, opposite side of the anterior superior iliac spine. Between the posterior inferior iliac spine and the ischial spine.
26
What are important landmarks in the Ischium?
Ischial Spine- Bump, closest to greater sciatic notch Ischial Tuberosity- below the ischial spine, thickening of the ischium Ischial Rami (2)- Inferior Ramus (ascending) is the thinner, inferior aspect of ischium, helps form Obturator Foramen (hole), and attached to the inferior ramus of the pubis. Superior Ramus (descending) projects down/posterior of the body. Ischial Body- Attaches the two rami, forms part of the lunate surface of the acetabulum.
27
What are important structures in the Pubis?
On the opposite side of the greater sciatic notch. Pubic Symphesis- Joins two pubes Pubic Rami (2)- Inferior ramus meets the ischial ramus forming the ischiopubic ramus. Superior ramus forms upper portion of obturator foramen Pubic Body- Joins the two ramus of the pubis. Pubic Tubercle- Forward facing projection on upper, medial portion of superior ramus of the pubis,
28
What is the Acetabulum?
Large, basin like concavity that lays in the Pubis, Ischium, and Ilium, where the head of the femur meets the hip.
29
Where does the sacrum sit?
Between the two Ilium. | Between the posterior superior iliac spine and the posterior inferior iliac spine of both ilium.
30
How are the hips fused together?
The pubic symphesis- via fibrocartilage
31
What is the pubic angle?
The connection between the inferior ramus of the ischium and pubis below the pubic synthesis, where an angle is formed (forming what looks like a triangle). It is larger in females.
32
How do you differentiate between right and left hip bones?
1. Locate GREATER SCIATIC NOTCH (large projection) 2. Use the Greater Sciatic Notch to find the PUBIS (inferior, and opposite side of the GSN) 3. Find ACETABULUM, and orient it so this side of the hip is facing you. 4. Whatever direction the pubis is facing, is the same as the hip. (i.e. Pubis facing the right, it is the right hip bone).
33
What is the scientific name for the hip bone?
Os Coxae
34
What part of the humerus attaches to the shoulder joint?
The head of the humerus
35
Where are the tubercles of the Humerus?
Greater (opposite side of the head, the lateral) and lesser tubercle (between greater tubercle and the head, slightly inferior). Both found at proximal part of humerus, near the head.
36
What is the name of the groove found between the greater and lesser tubercles of the humerus?
Inter-tubercular groove
37
Where and what is the deltoid tuberosity?
Mid-way down, laterally, on the humerus bone. Seen anteriorly and posteriorly. Where the deltoid muscle attaches.
38
Where are the Medial and lateral epicondyle found
Found distally, on the femur and humerus. Medial is larger.
39
What are the 3 ridges on the distal end of the humerus called?
Medial & Intermediate -trochlea | Lateral -Capitulum
40
Where does the ulna articulate with the humerus?
Olecranon Process of the Ulna articulates with the Olecranon Fossa (seen posteriorly, distally on the humerus). Together the Olecranon process and fossa form the humeroulnar joint. The Trochlear Notch (formed by the olecranon and coronoid process) of the Ulna articulates with the trochlea of the distal aspect of the humerus (articulation seen anteriorly)
41
How do you determine left from the right humerus?
1. Find the head of the humerus (should point medially) | 2. Find the 3 ridges (Indicates anterior view).
42
Which is more lateral, Radius, or Ulna?
The Radius
43
How can you differentiate between the Ulna and Radius?
The radius is shorter, and the Ulna has a 'hook' (olecranon process) at the proximal end where it attaches to the humerus
44
What is the Olecranon Process?
The 'hook" at the proximal end of the Ulna, where it sticks into the humerus (at the olecrenon fossa).
45
What is the groove beside the Olecranon Process called?
The Trochlear Notch. | It is where the trochlea of the humerus articulates and sits in.
46
What is the radial notch of the Ulna?
A lateral, proximal notch on the ulna where the head of the radius sits.
47
Where is the Radial Tuberosity?
On the medial, proximal side of the radius, just beneath the neck of the radius. Divided into a rough portion (posterior, insertion of tendon of the biceps brachii) and smooth portion.
48
What are the distal bumps sticking down on both the radius and ulna that do not help the radius and ulna to articulate with eachother?
The styloid processes of the radius/ulna
49
What does osseous mean?
Bone, typically 'os' prefix refers to bone
50
What is a long bone?
A bone longer than it is wide.
51
What are the regions of Long bones?
Epiphyses-there are 2, the proximal epiphysis, and distal- term meaning the ends of the long bone Diaphysis - the shaft- it is hollow, filled with yellow bone marrow). Metaphysis- lays between each epiphysis and diaphysis. Contains the epiphyseal line.
52
What are the layers of long bones?
Periosteum- Outer layer, most superficial. | Endosteum- Inner lining of the bone. Forms the lining of the Medullary cavity (the hollow spot in the shaft).
53
What is the hollow internal area of the shaft of a long bone called?
Medullary Cavity. Contains bone marrow.
54
What are the types of tissue (bone) within a long bone?
Compact Bone- Very strong & dense, exists between the peri and endosteum. Spongy Bone- (aka. cancellous or trabecular bone). Found in the metaphysis and epiphyses. Looks porous. Function is to reduce the weight of the bone and as a shock absorber. Deeper within the bone.
55
Where is bone marrow found?
In the medullary cavity (yellow bone marrow) of the diaphysis in the shaft of long bones and between the trabecula of spongy bone (red bone marrow).
56
What type of cartilage is found at the epiphysis of the long bones?
Articular cartilage- protective, prevents bone from rubbing on the bone (breakdown of this cartilage called osteoarthritis).
57
What is the anatomy of compact bone?
Contains OSTEONS (functional component)- each has a central (Haversian) canal, and several lamillae around the central canal, many osteocytes are found surrounded by lacunae.
58
How do osteocytes communicate with eachother?
Through arm like projections that extend through Canaliculi
59
What is the anatomy of Spongy bone?
Very porous, these pores contain bone marrow (in youth, it is typically red marrow, but most is converted to yellow bone marrow in diaphysis with red in epiphysis in adulthood). Trabeculae (the bony parts of the spongy bone, which has osteocytes sitting in lacunae). Endosteum- The lining of the trabeculae Periosteum- Superficial region.
60
What is bone marrow?
``` Used in production of white blood cells. Found within the porous regions of spongy bone. Produces Megakaryocytes (precursor to platelets) and Granulocytes (class of white blood cell containing neutrophils, eosinophils, and basophils). ```
61
What is a major difference between Compact and Spongy Bone?
Compact bone has osteocytes in lacunae organized into OSTEONS. Spongy bone has osteocytes in lacunae, not osteons.
62
What are the types of bone cells?
Osteoblasts, Osteocytes, & Osteoclasts
63
What are osteoblasts?
Cells that secrete bone matrix (which is hard) to form bone (build).
64
What are the two components of osteoblasts matrix?
Organic- contains the collagen proteins, and adds flexibility Non-Organic- Hydroxyapatite (all calcium salts that exist in the matrix), which gives the bone its hardness.
65
What happens when an Osteoblast works to build bone?
They secrete the bone matrix around themselves until the matrix is condense and hard enough that nutrients needed for cells (oxygen, glucose) have difficulty reaching the osteoblast. Eventually, the low O2 and glucose signal to the osteoblast to differentiate into new cell type, osteocytes.
66
What does an Osteocyte do?
Functions in maintaining the cell tissue and becomes the resident cell of the Lacunae.
67
What is the structure of the osteon?
Central Canal (Haversian)- in the centre of the osteon, contains vessels that supply blood to/from the osteocytes. Lamillae- Surrounding the canal in concentric circles (in rings) Lacunae- hold the osteocyte within it, found between the Lamellae Canaliculi- allow for communication of osteocytes with others in different lacunae.
68
What is the difference between interstitial and concentric lamelae?
Interstitial is found between the osteons, concentric forms concentric circles within the osteons and surrounds the lacunae.
69
What is an osteoclast?
A cell that removes collagen and hydroxapitate from the matrix to decrease the density of the bone matrix
70
What is the precurosor of an osteoblast?
Osteoprogenitor cell
71
What is bone deposition?
The process when the osteoblast builds bone
72
What is the precursor to osteoclasts?
From macrophages (which come from monocytes). Macrophages migrate to the bone, several will fuse together (forming a GIANT CELL), which is stimulated to differentiate into an osteoclast.
73
What is the ruffled border that is found in a type of bone cell?
The part of oseoclasts that move over the bone and secretes the degratory fluid.
74
What are the steps in bone resorption, include names of the degrading components released by osteoclasts.
2 Steps: 1. Dissolution of inorganic components (70%- minerals, hydroxyapatite crystals)- release of hydrogen ions (pumped by V-ATPase), 2. Digestion of organic materials (30%- collagen and ground substances that are phagocytosed by osteoclast)- Lysosomes release; Matrix Metalloprotease, Cathepsin K, Collagenases.
75
What happens to the calcium that is broken down from bones?
It goes back into the blood.
76
What elevates osteoclast activity?
Low blood calcium, elevated Para-Thyroid Hormones (causes osteoblast to secrete cytokine, osteoclast-stimulating factor. PTH is released by parathyroid when calcium is low to stimulate osteoclast activity, also inhibits osteoblasts), and decreased calcitonin (antagonist to PTH).
77
What is the epiphyseal line?
A bony region in the metaphysis of long bone, that came from the ossification of growth plates (aka. epiphyseal plate), which is a region of cartilage that allows the bone to grow in length during adolescents and ossifys during puberty.
78
Starting from the most medial, proximal part of the hand and moving in a clockwise motion, what are the carpals of the hand called?
Pisiform, Hamate, Capitate, Trapezoid, Trapezium, Scaphoid, Lunate, Triquetrum
79
What bones of the hand articulate with the radius?
Scaphoid and Lunate- forming the radiocarpal joint (wrist joint- synovial)
80
What bones of the hand articulate with the metacarpal of the thumb?
Trapezium
81
What bones of the hand articulate with the ulna?
None, it is prevented from articulation by the fibrocartilaginous ligament (articular disk).
82
Where are the heads of both the radius and ulna found?
Radius- proximal end, pointing medially. | Ulna- Distal end, pointing laterally (more lateral than the styloid process)
83
What are the carpals of the proximal row of the hand moving from most lateral to medial?
Scaphoid, Lunate, Triquetrum, Pisiform
84
What are the carpals of the distal row of the hand moving lateral to medial?
Trapezium, Trapezoid, Capatate, Hamate
85
Flip for helpful carpal mnemonic.
Lateral -> Medial 'She Looks Too Pretty' - Proximal Row 'Try To Catch Her' - Distal row
86
What are the main joints of the hands?
Carpo-Metacarpal Joints (Trapeziometacarpal joint for thumb) Metacarpal-Phalangeal Joints Proximal/ Distal Interphalangeal Joints (PIP and DIP- everything but thumb) Interphalangeal Joint of Thumb
87
What happens to the bones when there is low blood calcium?
Bone resorption is activated. Parathyroid glands (has calcium-sensing receptors) on posterior thyroid release Para-Thyroid Hormone from chief cells. PTH works to ^ blood Ca by stimulating osteoclasts (^ osteoblast release of cytokine, osteoclast-stimulating factor) and inhibiting osteoblast activity, while ^ Ca re-absorption at kidneys. PTH triggers formation of calcitriol from Vit D, which ^ intestinal absorption of Ca. PTH decreases thyroid release of calcitonin, which inhibits osteoclast activity. Osteoclasts will degrade bone tissue and release calcium in to the blood.
88
What is calcitriol?
The active form of Vitamin D, needed for absorption of calcium from the gut
89
What happens when blood calcium is high?
``` Parafollicular cells (or C-Cells) of the thyroid release Calcitonin. Calcitonin hormone inhibits osteoclasts and stimulates osteoblasts to deposit more bone matrix (by taking calcium from blood) resulting in bone deposition. ```
90
How do you differentiate between right and left scapula?
1. Find the spine of the scapula (indicates posterior view) and the inferior angle (indicates inferior portion of scapula) 2. Follow the spine out and up and it will point to the lateral side, indicating which side it belongs to.
91
What is the most lateral part of the scapula?
The Acromion
92
What bones articulate with the scapula?
1. The clavicle articulates with the acromion of the scapula to form the acromioclavicular joint. 2. The Humerus articulates with the glenoid cavity of the scapula (glenohumeral joint).
93
What is the most anterior part of the scapula?
The coracoid process.
94
What is the basin like cavity found on the lateral aspect of the scapula?
The Glenoid Cavity | This is where the head of the humerus articulates to form the glenohumeral joint (should joint).
95
What are the 3 fossas found on the scapula?
1. Supraspinous Fossa (above the spine, where the superspinatus muscle sits) 2. Infraspinous (below the spine, where the infraspinous muscle and teres minor sit) 3. Subscapular Fossa (houses rotater muscles and form shoulder joint).
96
What are the 2 ends of the clavicle?
1. The Acromial End- articulates with the acromion of the scapula 2. Sternal End- Articulates with the menubrium of the sternum forming the sternoclavicular joint.
97
Which end of the clavicle is the sternal?
The thicker and rounder end
98
What is in place of periosteum within cartilage?
Perichondrium
99
What are the shapes of bone types?
Long (femur), short (cuboidal- i.e. carpus), irregular (i.e. face), flat (typically protective function, i.e. cranium), sesamoid (protect tendon from excessive wear i.e. patella).
100
How does cartilage obtain oxygen and nutrients?
Diffusion, cartilage is avascular
101
What are the two kinds of ossification?
Endochondral Ossification- ossification of cartilage | Intramembranous Ossification- Direct ossification of mesenchyme cells
102
Where are bones derived from in terms of lineage?
Mesenchymal stem cells from the mesoderm
103
What is the process of endochondral ossification?
Mesenchymal cells condense into chondroblasts -> differentiate into chondrocytes forming cartilage -> cartilage calcifies (impregnated with Ca) and periosteal capillaries grow into the cartilage to supply inside -> capillaries and osteogenic cells form periosteal bud -> capillaries initiate primary ossification -> Primary ossification centre becomes the diaphysis
104
How does compact bone receive its nutrients?
Small branches of the periosteal arteries, without the periosteum, bone dies.
105
What is the nutrient foramina of bone?
The small openings which arteries and veins pass through the bone, typically at the epiphysis. Long bones with red bone marrow have large veins.
106
Where are lymphatic vessels found within the bone?
In the periosteum
107
Is there any nerve supply to bones?
Periosteal nerves is a sensory nerve supplying pain fibres to the periosteum Vasomotor nerves cause vasoconstriction/dilation within the bone itself to control blood flow, but that is it for within the bone.
108
What are the types of joints?
Synovial, fibrous, cartilaginous
109
Describe synovial Joints
Articulating bones joint by Joint Capsule (outer fibrous layer with inner serous synovial membrane) Synovial membrane secrete synovial fluid into inner space Inside capsule, articulating bones are covered with articular cartilage Most common, reinforced by accessory ligaments
110
Describe Fibrous Joints
Fibrous tissue unites articulating bones Types: Syndesmosis joint (more mobile, joins bones using fibrous tissue or ligament. I.e. interosseous membrane of radius and ulna) Dento-Alveolar Syndesmosis join (between tooth and its alveolar process of jaw, allows for minor movement).
111
Describe Cartilaginous Joints
Bones united by hyaline or fibrocartilage Primary Cartilaginous Joints- bones united by hyaline cartilage, some movement permitted. Typically not permanent (i.e. epiphyseal plate). Secondary Cartilaginous Joints- Bones joined by fibrocartilage, allowing for strength, shock absorption, and some flexibility (i.e. joints of spinal column)
112
What movement does a pivot joint allow, name an example?
Uniaxial Rotation around central axis I.e. the axial bone (C2)
113
What movement does a condyloid joint allow, name an example?
Biaxial Can perform adduction/abduction, and extension/flexion, but circumduction is limited metacarpophalangeal joint
114
What movement does a saddle joint allow, name an example?
Biaxial Can perform adduction/abduction, extension/flexion, and circumduction, however bones are shaped like a saddle. Carpometacarpal joint of 1st digit
115
What movement does a ball and socket joint allow, name an example?
Multiaxial Can perform flexion/extension, abduction/adduction, medial/lateral rotation, circumduction (however structures can limit freedom) Head of femur in acetabulum of hip
116
What movement does a plane joint allow, name an example?
Uniaxial Allows sliding of bones across surfaces Intercarpal joints
117
What movement does a hinge joint allow, name an example?
Uniaxial Back and forth motion Ulna-Humerus Joint
118
Do joints receive any blood or nerve supply?
Yes, articular arteries form network (anastomose) to joint, and articular veins carry blood away. Yes, articular nerves have sensory nerve endings in the joint capsule supply joints. Hilton law states nerves supplying a joint also supply the muscles moving the joint and the skin covering their distal attachments. Articular joint nerves also contribute to proprioception
119
How does Rickets impact the bone?
Rickets is a low mineral density in the bones causing bending of bone from the weight of the body. Vitamin D is normally converted to calcitriol which is needed in Calcium absorption in the gut, but without, Calcium absorption is lowered causing low mineral density in bones. Increasing incidence in Scotland due to low sunlight exposure in kids
120
What is Osteogenesis Imperfecta?
Genetic mutation causing deficiency in collagen production which results in bone that is easily fractured.
121
What is the diploe?
The name for bone-marrow-containing spongy bone within the skull
122
How can long bones grow?
Interstitial growth by cartilage undergoing mitotic division on the bone's surface (near epiphyseal plate) and calcifying Appositional growth- growth occurring from the periosteum or endosteum that increases bone width by building bone on top of existing bone
123
What is a herniated spinal disc, and where is it most common?
When the intervertebral disc becomes dislodged, or pushed out. Most common in lumbar part of vertebral column (carries the most weight)
124
What are the girdles of the body?
``` The groups of bones that connect the limbs to the body. Pectoral Girdle (Scapula, clavicle) connect upper limbs Pelvic Girdle (Ileum, Ischium, Pubis) connect lower limbs ```
125
What is the bone that connects the upper limbs to the body?
Only the clavicles | Allows for lots of movement
126
What is the difference between appositional and interstitial growth?
Interstitial growth is when chondrocytes replicate and create more matrix, increasing the bone's length at the diaphyseal side of the epiphyseal plate. Appositional growth is when chondrocytes within the perichondrium divide and produce matrix contributing to increased bone thickness.
127
What are the types of bone growth?
Endochondral | Intramembranous
128
Describe is the process of endochondral bone growth.
Mesenchymal cells differentiate into chondroblasts which build cartilage, chondroblasts which are surrounded by cartilage matrix mature into chondrocytes. Chondrocytes in the matrix begin to hypertrophy, and will burst, causing a change in pH which signals ossification. The ossification causes death of the chondrocytes, which leaves small spaces, lacunae. Periosteal Bud penetrates perichondrium, initiating mesenchymal cell differentiation into osteoblasts which form bone collar beneath the perichondrium, eventually leading to periosteum. Osteoblasts are carried to matrix and begin to form spongy bone within the centre of the bone, which is broken down by osteoclasts to form the medullary cavity, and eventually the diaphysis, this is PRIMARY OSSIFICATION. SECONDARY OSSIFICATION occurs at the epiphysis in a similar process, however, the centre of spongy bone is left, and the osteoblasts develops from the inner portion and grows outwards, and mesenchymal stem cells grow from the externus inwards
129
Describe the process of intramembranous ossification.
Mesenchymal stem cells directly condense and differentiate into osteoblasts (not chondroblasts). Osteoblasts secrete organic bone matrix (collagen) around themselves, and once surrounded, they mature into osteocytes in lacunae. Non-organic bone matrix is added later forming bony spicules. The matrix forms spongy bone consisting of trabeculae, and blood vessels that were in this region differentiate into red bone marrow. Mesenchyme on outside of bone condenses into compact bone, and most external portions of spongy bone are remodelled into compact bone.