smooth, contoured ends of bones that form joints with other bones.
cylindrical to rounded end.
spherical to rounded surface
Depressions and Openings
result from compressive forces or allow passage of soft tissues.
pocket or cup
prominences on bones resulting from tension (pulling) forces, attachment points for ligaments and tendons.
breakdown of bone matrix by osteoclast secretions
formation of new bones by osteoblasts
deposition of mineral salts in bone by osteoblasts and osteocytes.
Bone Remodeling Process
bone resorption, ossification, calcification
resorption=ossification and calcification
hormone that inhibits osteoclasts. Negative feedback loop in response to high blood calcium. Produced by thyroid. Less bone is resorbed and more calcium remains in the bone.
Negative feedback loop in response to low blood calcium. Produced by the parathyroid gland. Stimulates osteoclasts. More bone resorbed, and calcium released from bone matrix enters bloodstream.
Steps of Fracture Repair
fracture hematoma (forms within hours), Cartilage Callus (forms within weeks), bony callus (forms within months), bone remodeling (months to years)
injured bone tissue forms a clot. Phagocytic cells and osteoclasts remove damaged tissue.
fibroblasts enter hematoma and differentiate into chondroblasts (outside bone) and osteoblasts (inside bone). Produce hyaline cartilage
Beginning near healthy bone ends, osteoblasts replace cartilage callus with spongy bone. Bridges broken ends and stabilizes fracture.
bony callus replaced with "normal" bone.
bones arranged around body's longitudinal axis
surrounds and protects brain.
create cavities containing special senses (nasal cavity, orbits, mouth); assist in eating.
cavities in some bones. Lined with mucous membranes and connected to the nasal cavity; produce mucus. Act as resonating chambers. Moisturizes and warms inhaled air.
midsagittal division of nasal cavity. Formed by vomer and ethymoid bones and septal cartilage.
separates nasal cavity from mouth. Formed by incisive, maxillary and palatine bones.
Spine. Flexible rod that surrounds and protects the spinal cord, and serves as an attachment site for the head, thoracic cage and hind limbs.
Solid, ventral portion of vertebrae. Articulates with adjacent vertebral bodies.
fibrocartilage discs between vertebral bodies. Have a soft, pulpy center which acts as a cushion. Form cartilaginous joints which are slightly moveable.
Dorsal to the body.
hole in the arch which contains the spinal cord.
formed by all vertebral foramina lined up.
transverse, spinous, cranial and caudal articular processes.
Lateral, muscle attachment sites.
Dorsal, muscle and ligament attachment sites.
Cranial and Caudal Articular Processes
Sites of intervertebral articulation; joint surfaces called facets. Intervertebral joints--synovial gliding joints.
Divisions of Vertebral Column
cervical vertebrae, thoracic vertebrae, lumbar vertebrae, sacrum, coccygeal vertebrae.
Found in neck. Usually seven.
C1. Holds up skull. Ring of bone with two large ala (attachment sites for muscle). Articulates with head.
C2. Dens (peg-like processes) articulates with atlas. Has the atlantoaxial joint--synovial pivot joint.
found in chest. Usually 13-18. Body and transverse processes have facets for articulation with ribs.
found in lower back. Usually 5-7. Largest, thickest vertebrae.
3-5 fused vertebrae. Attachment site for pelvic girdle.
found in tail. Highly variable numbers between and within species.
encloses and protects organs of thoracic cavity.
usually 1 pair for each thoracic vertebra. Dorsal end articulates with vertebral body and transverse processes. Contain synovial gliding joints that allow thoracic cage to expand when breathing.
attach to sternum via costal cartilages.
don't attach to sternum. Attach to costal cartilages of other ribs.
asternal ribs. most caudal ribs with no ventral attachment.
space between adjacent ribs.
breastbone. made up of rod like bones called sternebra. Manubrium is the cranial sternebra and the xiphoid is the caudal sternebra.
connection between two bones, bone and cartilage, or bone and teeth.
how to name joints
usually named after the articulating structures. some large, complex joints are given special names. skull joints are named using directional terms.
connected by fibrous connective tissue. no movement. Found in sutures, and gomphoses (tooth joints).
connected by cartilage. slightly moveable as cartilage compresses. Ex: pubic and mandibular symphysis.
slightly moveable joint.
freely moveable joint.
freely moveable joints. two bones covered by articular cartilage. Contain a joint cavity, joint capsule, synovial membrane and synovial fluid.
small space between bone ends.
connective tissue enclosing joint cavity. Fibrous outer layer made of dense irregular connective tissue.. Attaches to the periosteum.
inner loose connective tissue layer of the joint capsule.
secreted by synovial membrane. viscous fluid that lubricates the joint.
Structures associated with synovial joints
ligaments, menisci, bursae, tendon sheath.
dense fibrous connective tissue that attaches bone to bone. Extracapsular: outside joint capsule. Intracapsular: inside joint capsule.
extra pads of fibrocartilage between articulating bones. stabilize joint and provide extra cushioning.
sac-like, synovial structures located at points of friction, associated with joint. filled with viscous fluid to provide cushioning.
tube-like bursa surrounding tendons at sites of friction.
Types of synovial joints
gliding joint, hinge joint, pivot joint, ellipsoid joint, ball-and-socket joint.
surfaces are relatively flat, glide over each other (intercarpal joints).
one rod-like and one groove-like surface, allows monaxial flexion or extension (elbow).
one pointed and one ring-like surface. One bone rotates around the other (atloaxial joint, C1-C2 vertebrae).
one convex oval and one concave oval surface. Allows biaxial movement (metacarpophalangeal joints).
one ball-like one cup-like surface. Allows multiaxial movement (shoulder and hip).
bones of the limbs. function as levers for movements of skeletal muscles.
shoulder blade. Does not articulate with axial skeleton. Strongly attached to the thorax by muscles.
brachium of forelimb. Proximal end attaches to scapula, creating the synovial ball-and-socket joint. Distal end articulates with radius and ulna creating the synovial hinge joint (elbow).
antebrachium of forelimb. Proximal end articulates with medial humerus. Distal end connects with lateral carpus.
antebrachium of forelimb. Main weight bearing bone. Proximal end articulates with lateral humerus. Distal end connects with medial carpus.
two rows of short bones forming three joint regions. Radiocarpal joint, intercarpal joint (proximal row connects with distal row), carpometacarpal joint (distal row connects to metacarpals)
bones of forepaw. Numbered 1-5 starting medially. Cats and dogs have all five. Ruminants have 3 and 4 fused, with 2 and 5 as remnants. Horse has only the 3rd metacarpal with 2 and 4 as remnants. (splint bones)
digits of forepaw. Most digits have 3 phalanges--proximal, middle and distal. Cats and dogs have 5, ruminants have 4, horses have 1 digit..
2 coxal bones.
2 coxae articulate with each other. Slightly moveable cartilagenous joint.
coxae articulate with sacrum. Attach directly to axial skeleton. Synovial gliding joint.
form from three embryonic bones which fuse. Form the ilium, ischium and pubis.
craniodorsal portion of pelvis. Forms the sacroiliac joint.
caudal portion of pelvis.
ventromedial portion. Forms pubic symphysis.
formed by ischium and pubis. Makes the pelvis lighter.
deep, rimmed socket which articulates with femur. Formed where ilium, ischium, and pubis join.
hip joint. Synovial ball-and-socket joint.
hindquarter or thigh region.