Anatomy Exam 1 (copy)

Osteology

the description of the skeleton

Arthrology

the description of the Joints

Myology

the description of the muscles

 Splanchnology

the description of the Viscera including the following subdivisions of the soft organs of the body

Angiology

the description of the organs of circulation

Neurology

the description of the nervous system

Aesthesiology

the description of the sense organs and common integument

Regional Anatomy

rather than focusing on individual organs or systems, it examines the anatomical features of a particular area of the body

Topographic Study

methods by which the relative positions of various parts of the body are accurately determined.

Anatomical Position

 the body is assumed to be standing, the feet together, the head and eyes facing forwards and palms of the hands facing downwards.

Head Motion

extends/flexes (YES motion) at the occipital-atlantal joint and rotates (NO motion) at the atlantal-axial joint

Spine Motion

extends dorsally and flexes ventrally

Pelvic Girdle

made up of two hip bones that are connected at the middle front part called the pelvic symphysis, and at the back, they connect with the sacrum. Each hip bone, also known as the os coxae, is formed by the fusion of three main bones: the ilium, ischium, and pubis.

Shoulder Girdle

Scapula, coracoid, and clavicle

Ilium

largest and most cranial pelvic bone and articulates with the sacrum.

Ischium

most caudal pelvic bone

Pubis

Ventromedial to the ilium and cranial to the large obturator foramen.

Acetabulum a socket

formed where the three pelvic bones meet. It receives the head of the femur in the formation of the hip joint.

Round ligament

connects the fovea capitis (a depression on the head of the femur) to the acetabulum (a socket in the hip bone)

The Hindlimbs Acetabulum corresponds to what forelimb bone?

Glenoid cavity

The Hindlimbs femur corresponds to what forelimb bone?

Humerus

The Hindlimbs tibia/fibula corresponds to what forelimb bone?

Radius/ulna

Pubic symphysis in males

Convex

Pubic symphysis in females

Concave

Tuber coxae

“Hook bone”

Obtrator foramen

Largest foramen in the body

Ischiatic tuber

“Pin bone”

The sacropelvic joint

joint between the sacrum and the two iliac bones of the pelvis.

The articulate line

line that separates the upper two-thirds of the ilium from the lower one-third. Marks the transition point between the thick, weight-bearing portion of the ilium and the thinner, non-weight-bearing portion as serves as a point of muscle attachment.

The obturator foramen

a hole in the pelvic bone that is covered by the external and internal obturator muscles as well as a membrane. This foramen allows the passage of blood vessels and nerves through it. Damage to this structure can happen particularly during childbirth and can cause difficulty in moving the hip and leg.

Adult acetabula

sockets of the hip bones that connect with the femoral head to form the hip joint, are fused and fully developed. This fusion provides stability and structural integrity to the hip joint.

Young acetabula

are not fully fused. They contain growth plates or cartilaginous areas that allow for further development and growth of the hip joint. This flexibility that enables adjustments and adaptations to accommodate the growth of the bones and tissues during the growth phase

Ramus

refers to a branching part of a bone. It's like a branch extending from the main body of the bone. It provides extra surface area for muscle attachments and helps the bone withstand forces. It plays a crucial role in the bone's strength, stability, and movement.

Largest bone in the body

Femur

The caudal surface of the femur

plays a role in the movement of abduction

The cranial surface of the femur

plays a role in extension

The patella locking mechanism

a biomechanical mechanism that helps stabilize the knee joint during extension. It involves the interaction between the patella and the trochlear groove on the femur. As the knee extends, the patella slides within the groove, and when the knee reaches full extension, the patella locks into place within the groove.

The fabella

a small sesamoid bone found behind the knee joint, embedded within the tendon of the lateral head of the gastrocnemius muscle.

The cruciate ligaments

connective tissue located within the knee joint, specifically in the area known as the intercondylar fossa. There are two in each knee: the ACL and the PCL. They form an "X" shape, crossing each other within the knee joint. They play a crucial role in stabilizing the knee and controlling its movements

The tibia and fibula, when considered together, are commonly referred to as

the true leg or the crus

The interosseous space

the area between the tibia and fibula. It contains a collagenous membrane.

The meniscal ligaments

The caudal ligaments connect the back part of the medial meniscus to the tibia bone, while the cranial meniscal ligaments connect the front part of the medial meniscus to the tibia bone. These ligaments help stabilize and support the medial meniscus during knee movements

The axial skeleton

the vertebral column, rib cage, skull, and sternum. Supports the trunk, carries the skull, and protects the spinal cord. Provides attachment for the ribs & back muscles. Moves as flexion, extension, and lateral flexion but is limited by shape

Vertebrae structure

share a common basic structure: a body (Except the C1), arch, processes, and foramen. The vertebrae are classified as short bones (ossa brevia). 

Nutrient foramen

Provides nutrients to the bone

What passes through the vertebral channel

Spinal cord, meninges, intervertebral foramina, ligaments, nutrient foramina, connective tissue (CT), and fat

Meninges

protective layers of membranes that surround and support the spinal cord

Vertebral foreman 

Single space between the arch disappears as the tail progresses caudally. 

The first (atlas) and second (axis) cervical vertebrae

are highly modified to allow free movement of the head. It is not present in ruminants.

The zygapophyseal joint

a synovial joint located between the superior and inferior articular processes of adjacent vertebrae. These joints are found on both sides of the vertebral column and play a crucial role in stability, movement, and limiting excessive motion. 

Transverse foramen 

Houses the vertebral artery

Facet

Flat or slightly convex surface found on a bone.

Fovea

Shallow pit or depression found on a bone. 

Vertebrae in carnivores

7 cervical vertebrae, 12-14 thoracic vertebrae, 6-7 lumbar vertebrae, 3 sacral vertebrae 20-23 caudal vertebrae.

Cartilaginous joint

United by cartilage (hyaline cartilage or fibrocartilage), have no cavity, and have little or no movement. Examples are: pubic/ischiatic symphysis, mandibular symphysis

Mandibular symphysis in pigs

stronger that other animals, almost equal to skull size and is tightly connected

Synovial joint 

“True joints” united by a joint capsule, have a joint cavity, are freely moveable, and contain fluid helps lubricate the joint.

Ginglymus (hinge) joints

Joints move only in their sagittal plane (flexion, extension hyperextension) uniaxial allowing unidirectional movements at right angles (fetlock, elbow). Type of Synovial joint 

Plane joints

Have only slight gliding movement between relatively flat apposed surfaces: (carpal bones, cranial and caudal articulations between vertebrae). Type of Synovial joint 

Trochoid (pivot) joints

Rotary movement occurs around one axis: uniaxial (atlanto-axial joint). Type of Synovial joint. “No” movement

Spheroid (ball and socket) joints

Consists of a spheroidal head fitting in a socket allowing universal movement (shoulder and hip joint). Type of Synovial joint 

Condylar joint

Bonvex articular condyles articulates with concave articular surface, can perform flexion, extension and little rotation (temporomandibular joint, femorotibial joint). Type of Synovial joint

Ellipsoid joint (ginglymus)

Baxial joint formed by ellipsoidal convex surface fitting into concavity of another bone. Can perform flexion, extension, abduction, addiction and small rotation (atlantooccipital joint).  Type of Synovial joint. “Yes movement”

Diarthrosis

Freely moveable joints

Amphiarthrosis

Slightly moveable joints

Synarthrosis

No movement within the joint

Meniscus

acts as a shock absorber. Intracapsular and are not covered by synovial membrane. Prominent in stifle and TMJ

Ligament

Connective tissue bands that extended from bone to bone

Tendons

Connective tissue bands that connect muscle to bone 

Synsarcosis

muscle is the means of articulation, not a “true joint”. Found in the forelimb-trunk and also connects hyoid-sternum joint

ACL

limits knees forward movements

CCL

limits knees backward movement

TMJ

condylar joint between mandibular fossae of the temporal bone and condyloid process of the mandible. Has a meniscus/articular disc

Clavicle/collar bone

variable size with accordance with the type of locomotion and coordinated movements made by the thoracic limbs. It is reduced in animals that lean on the thoracic limbs to walk. Development and complexity vary, being maximum in man.

Clavicle in dogs/cats

it is a vestigial bone that is not articulated. It is buried in the shoulder region muscles and doesn't connect with other bones (Synsarcosis)

the clavicle of the mouse

well developed and articulates with the sternum and also participates in the shoulder joint, where it contacts the acromion of the scapula.

Feline scapula

broad and short, spine is tall. The metacriion, suorahamate, acromion, and hamate are all present and the caracoid process is elongated

Canine scapula

slim and tall, scapula spine is short. Both the metacromion and suprahamate are absent. The acromion and hamate are present, and the caracoid process is short.

Scapula fractures

rare due to protection from the muscle attachments

Intervertebral disc

Inner layer is nucleus pulposus. Outer layer is annulus fibrosis

Atlanto occipital joint

“Yes joint” (synovial joint in the vertebral column)

Atlanto axial joint

“No joint” (synovial joint in the vertebral column)

Muscles

are the structures formed by the bundles of muscle cells in the form of fibers and possess the property of contraction on stimulation. They are derived from mesenchymal cells.

Skeletal muscles

are long, striated, and voluntary. They attach to bone, fascia, and cartilage, and their fibers are bundled together. Each fiber has coverings, and the entire muscle is enveloped. Muscle fibers contain various components and have rapid contractions but fatigue easily.

Smooth muscles

are involuntary, spindle-shaped muscles with a single nucleus. They are short in length and primarily found in the walls of hollow visceral organs

Cardiac muscle

is a type of muscle that performs involuntary actions. It is characterized by intercalated discs, multinucleation, striations, and a branched structure.

Myofilient

Proteinous structure that forms myofibrils which form myofibers (muscle fibres) that form fasciculus (muscle tissue)

Accessory process

Assists the caudal articular process to prevent excessive movement. Some vertebrae don't have mammalian or accessory processes. Mammalian process only last 3 thoracic v and on all lumbar. Accessory process present on lumbar absent in thoracic.

Collagen type 1

Strongest type found in the vertebral fibrocartilaginous joint.

Costal fovea

Provides attachment points for the ribs

Ligamentum nuchae/nuptial ligament

Provides attachments and helps connect vertebrae to each other.

Nucleus pulposus

Jelly-like material that acts as a shock absorber between the vertebrae. Can herniate into the intervertebral foramen and compress the spinal cord, causing back pain.

Sacral Fusion

three bones in dogs (as many as five in ruminants). Triangular in shape, zero potential movements within the vertebrae.

Sacrum fusion ages

Dogs and pigs fuse within approximately 1.5 years. Ruminants fuse within 3-4 years. Horses fuse within 4-5 years.

Thoracic vertebra size

thoracic vertebrae generally increases from the first thoracic vertebra (T1) to the last thoracic vertebra

Thoracic inlet

Formed by T1, 1st pair of ribs, and manubrium.

Origin

The proximal fleshy and fixed end. Near joint

insertion

The distal fibrous narrow or flat end. Away from joint

Tendon

tendon When the insertion is a fibrous cord. Are made up of closely packed bundles of collagen and have a shiny white appearance. They connect muscles with bones. The collagenous bundles in are continuous with the collagenous bundles of perichondrium or periosteum at one end and with those of the fibrous muscle sheath (epimysium) at the other end.

Aponeurosis

When the insertion is a thin sheets and provides the muscle a wide area of attachment.