Skeletal+part+2.docx

Skeleton Part 2 Chapter 6 Objectives To continue identifying the bones in the axial skeleton Examine the characteristics of each Begin identifying the bones of the appendicular skeletal system & Examine their characteristics Hyoid Bone Also called the hyoid apparatus Located in the neck Suppo...

Skeleton Part 2 Chapter 6 Objectives To continue identifying the bones in the axial skeleton Examine the characteristics of each Begin identifying the bones of the appendicular skeletal system & Examine their characteristics Hyoid Bone Also called the hyoid apparatus Located in the neck Supports the base of the tongue, pharynx, larynx It aids in swallowing Vertebral Column Characteristics Extend from the skull to the tail Divided into 5 regions Cervical Thoracic Abdominal Sacral Coccygeal Vertebrae Characteristics Typical vertebrae consists of: Body Arch Processes Three kinds of processes Spinous process Transverse process Articular process Vertebrae Consist of a body, an arch, and processes Intervertebral disks: cartilage separating bodies of adjacent vertebrae Houses the Spinal Column Intervertebral discs Adjacent vertebrae are separated from each other by little shock absorbers Cervical Vertebrae Neck 7 vertebrae (C1-C7) First two vertebrae Atlas (C1) Larger of the two Has wing like transverse processes Axis (C2) Large blade like spinous processes Fits into the caudal aspect of the atlas Thoracic Vertebrae Dorsal to thorax Number varies according to species Dog and Cat (T1-T13) Characteristics Tall spinous processes Lateral articular facets Forms a joint with the ribs Lumbar Vertebrae Dorsal to Abdomen Varies according to species and sometimes within a species Dog and Cat (L1-L7) Characteristics Biggest Support all the weight of the abdominal organs Sacral Vertebrae Dorsal to the pelvis Dog and Cat (S1-S3) Characteristics Fused together to forms a single structure called the sacrum Forms a joint with the pelvis Sacroiliac joint Coccygeal Bones of the tail Varies significantly with species and within species Cat (Cy5-Cy23) Dog (Cy20-Cy23) The appearance of the first coccygeal vertebrae are similar to other vertebrae but the caudal vertebrae are just rods of bone Ribs Flat Bones Form the lateral walls of the thorax Dorsal ends articulate with the thoracic vertebrae These joints aid in ventilation Help support and protect the structures of the thorax Ribs usually equal the number of thoracic vertebrae Paired Ribs Ribs are divided into two parts Dorsally made of bone Ventrally made of cartilage Called costal cartilage Junction of the bone and cartilage is called the costochondral junction The costal cartilage either joins the sternum (sternal ribs) or the ribs above them (asternal ribs) The cartilage of the last two ribs may not attach to anything -These are called floating ribs Sternum Breastbone Made up of rod like bones called sternebrae Important landmarks Manubrium First and most cranial Xiphoid process Made of cartilage Appendicular Skeleton Front leg-thoracic limb Scapula Humerus Radius Ulna Carpal bones Metacarpal bones Phalanges Hind Leg-pelvic limb Pelvis Femur Tibia Fibula Tarsal bones Metatarsal bones Phalanges Scapula Shoulder blade Flat Triangular bone Prominent longitudinal ridge on its lateral surface (spine of the scapula) It articulates (glenoid cavity) with the humerus Humerus Long Bone Greater tubercle-process where the shoulder muscles attach Distal end forms the elbow joint along with the radius and ulna Condyles: articular surfaces Trochlea: articulates with ulna Capitulum: articulates with radius Olecranon fossa: indentation above condyle Epicondyles: non-articular Radius Form the forearm or antebrachium Main weight bearing bone between the radius and ulna Along with the ulna helps form the elbow joint Ulna Forms the major portion of the elbow joint Olecranon process-point of the elbow Site of tendon attachment Anconeal process-tucks into the olecranon fossa located on the distal end of humerus when the elbow is straightened Carpal Bones Two rows of short bones Parallel to each other Proximal row and a distal row Proximal row Radial carpal bone Ulnar carpal bone Accessory carpal bone (palmar aspect) Distal row are give numbers Moving medially to lateral 1st-4th Metacarpal Bones Extend distally from the distal row of carpal bones to the proximal phalanges Corresponds to our fingers Named moving medial to lateral Metacarpal I-V Phalanges Digit is an anatomical term for one of our fingers or toes Each digit is made of 2-3 phalanges Phalanges are individual bones that make-up digits Each digit has a proximal, middle and distal phalanx They also have two proximal sesamoid and one distal sesamoid bone Dewclaw has only two bones a proximal and distal phalanx http://vet.osu.edu/index.php?id=2379 Review Know the two internal bones of the cranium and face Location of the hyoid bone and its function Describe the design and function of the vertebral column, know the vertebral formulas for the dog, cat and horse Know the characteristics of the sternum and the landmarks Know how the appendicular skeletal system is divided Be able to identify the bones of the thoracic limb