The interactive dog atlas · for the classroom
27 cards, six per A4 sheet, to cut along the lines. Choose the set and, if you want an exercise, hide the name (the student writes it) or the text (the student writes the definition). No student names, no score.
musculus temporalis
The most massive muscle of the head in carnivores, thick and elastic. It arises from the temporal fossa (and from the sagittal crest) and inserts by a tendinous sheet on the coronoid process of the mandible. It closes the mouth, so it bites, and it guards the temporomandibular joint against forward luxation.
Where: On the sides of the skull, in the temporal fossa, from above the eye to the nape.
musculus masseter
It arises from the lower edge of the zygomatic arch and inserts on the lateral face of the mandible (the masseteric fossa). It raises the mandible, that is, closes the mouth; together with the temporalis it gives the bite its force. The only masticatory muscle that opens the mouth is the digastricus, on the underside of the jaw.
Where: On the cheek, between the zygomatic arch and the mandible.
musculus brachiocephalicus
It links the arm to the head and neck and has two parts, separated by the clavicular intersection, where the vestige of the clavicle lies: the cleidobrachialis, attached to the humerus, and the cleidocephalicus, attached to the nape and the mastoid process. It pulls the limb forward; when the limb is fixed under the body's weight, it extends the neck or turns the head.
Where: The band on the front of the neck, from the head to the humerus.
musculus sternocephalicus
It arises from the manubrium of the sternum and runs up the underside of the neck to the mastoid process and the occipital region of the skull. It flexes the head and neck; when only one side contracts, it tilts and rotates the head toward that side.
Where: On the underside of the neck, from the sternum to the head.
musculus trapezius
A broad, triangular muscle with a cervical part and a thoracic part, separated by an aponeurotic zone. It arises from the dorsal midline, from the third cervical vertebra to the ninth thoracic, and inserts on the spine of the scapula. It raises the forelimb and pulls it forward.
Where: On the withers and the upper part of the thorax, above the shoulder blade.
musculus latissimus dorsi
A broad muscular sheet that arises from the thoracolumbar fascia (the lumbar and last thoracic vertebrae, the last ribs) and converges on the teres major tuberosity of the humerus. It pulls the free limb backward and brakes its advance; in the greyhound it is among the muscles that produce most of the mechanical work of acceleration.
Where: On the sides of the thorax, behind the shoulder blade, from the loin to the upper arm.
musculus deltoideus
In the dog it has two parts, scapular and acromial. It arises from the spine and the acromion of the scapula and inserts on the deltoid tuberosity of the humerus. It flexes the shoulder joint and raises the humerus.
Where: Over the shoulder joint, from the shoulder blade to the humerus.
musculus triceps brachii
The strongest muscle of the forelimb. The long head arises from the caudal border of the scapula, the other heads from the humerus (in the dog there are four, although the name says “three”); all insert on the olecranon, the point of the elbow. It extends the elbow at every stride; the long head also flexes the shoulder.
Where: The back of the upper arm, from the shoulder blade and humerus to the point of the elbow.
musculus biceps brachii
In the dog it has a single head. It arises from the supraglenoid tubercle of the scapula and inserts by a branched tendon on the tuberosities of the radius and ulna. It flexes the elbow and extends the shoulder.
Where: The front of the upper arm, mostly on the medial face; from the side only its edge is visible.
musculi pectorales
Extrinsic muscles that fasten the limb to the sternum. The superficial pectorals insert on the crest of the greater tubercle of the humerus and support the limb, pulling it inward; the deep pectoral, the heaviest muscle of the forelimb in the greyhound, pulls the trunk forward over the supporting limb and extends the shoulder.
Where: On the chest, from the sternum to the humerus; from the side their edge shows below the thorax.
musculus serratus ventralis
It arises by digitations from the ribs and the cervical vertebrae and inserts on the medial face of the scapula. Since the forelimb has no bony joint with the thorax, this muscle is the “sling” that carries the weight of the trunk between the two shoulder blades; it also helps with inspiration.
Where: On the sides of the thorax, below the shoulder blade; it shows as a band with “teeth” on the ribs.
musculus obliquus externus abdominis
Its fibers arise from the caudal ribs and the thoracolumbar fascia and run obliquely downward and backward, to an aponeurosis attached to the linea alba. It compresses the abdominal viscera (the “abdominal press”), which helps with expiration, and supports the abdominal wall.
Where: The lateral wall of the abdomen, from the last ribs to the linea alba.
musculus longissimus
The epaxial muscles lie dorsal to the spine and extend it; the largest of them, the longissimus, runs from the pelvis to the head and is the longest muscle in the body. At the gallop, flexion and extension of the spine greatly lengthen the stride: these muscles are part of the engine of running.
Where: Along the vertebral column, above it, from the pelvis to the head; in the drawing, the band below the trapezius and latissimus.
musculus gluteus medius
It arises from the gluteal surface and the crest of the ilium and inserts on the greater trochanter of the femur. It extends the hip joint, so it pushes the body forward; it also tends to rotate the femur with the stifle inward, a tendency counterbalanced by the caudal hip muscles.
Where: On the croup, above the hip, on the wing of the ilium.
musculus gluteus superficialis
It arises from the gluteal fascia, from the sacrum and from the sacrotuberous ligament, and inserts on the third trochanter of the femur. It extends the hip joint.
Where: On the croup, behind the gluteus medius, toward the tail.
musculus biceps femoris
The largest of the muscles at the back of the thigh (the “hamstrings”). It arises from the ischiatic tuberosity and the sacrotuberous ligament and inserts widely on the fascia lata and crural fascia, on the tibia and, through the calcaneal tendon, on the calcaneus. It supports the body in the stance phase, flexes the stifle at the start of the swing and extends the hock; together with the adductor it is the strongest extensor of the hip.
Where: The lateral and rear part of the thigh, from the ischium to the stifle and hock.
musculus semitendinosus
It arises from the lateral angle of the ischiatic tuberosity, between the biceps femoris and the semimembranosus, and inserts on the medial face of the tibia and on the calcaneus. It extends the hip and hock and flexes the stifle of the free limb; it is one of the main extensors of the hip, so part of the engine of propulsion.
Where: The rear edge of the thigh, from the ischium to the tibia and calcaneus.
musculus quadriceps femoris
Four heads: the rectus femoris arises from the ilium, the three vasti from the femur. All insert on the patella, and the patella is linked to the tibial tuberosity by the patellar ligament. It extends the stifle; the rectus femoris also flexes the hip and is especially powerful in the greyhound.
Where: The front of the thigh, from the pelvis and femur to the patella.
musculus gastrocnemius
It has two heads, which arise from the lateral and medial supracondylar tuberosities of the femur, and it inserts on the calcaneus through the common calcaneal tendon. It mainly extends the hock and slightly flexes the stifle; its lever arm at the hock stays large over the whole range of motion.
Where: The back of the lower leg, from the femur to the point of the hock.
tendo calcaneus communis
It is not a single tendon: its core is formed by the tendons of the gastrocnemius and the superficial digital flexor, with contributions from the biceps femoris, semitendinosus and gracilis. That is why a dog could still stand even if the gastrocnemius and the superficial digital flexor were paralyzed.
Where: Above the point of the hock, on the back of the lower leg.
diaphragma
A large, flat, dome-shaped muscle that completely separates the thoracic cavity from the abdominal cavity. It arises from the lumbar vertebrae (the crura of the diaphragm), from the ribs, the costal cartilages and the xiphoid process, and inserts on the central tendon. It is the main muscle of inspiration; the muscles of the thoracic wall help, especially during exertion.
Where: Inside the trunk, between the thorax and the abdomen; in the drawing, the dotted line bulging forward.
m. orbicularis oris · orbicularis oris
The orbicularis oris lies in the thickness of the lips, around the opening of the mouth, with no attachment to bone. In carnivores, the part in the upper lip is interrupted on the midline by a raphe, and in the dog the muscle is weakly developed. Each half is supplied separately by the facial nerve of its own side. The platysma, the cutaneous muscle of the neck, usually attaches to it.
Where: In the thickness of the lips, around the opening of the mouth.
m. levator nasolabialis · levator nasolabialis
The levator nasolabialis starts broadly from the frontal and nasal bones, in the dog also from the upper edge of the maxilla, and runs down under the skin to the upper lip and the wing of the nostril. It lifts the upper lip, pulling it laterally, and pulls on the wing of the nostril. In carnivores it is very broad and without clear limits. Its motor nerve is the dorsal buccal branch of the facial nerve.
Where: From the forehead and the nasal bones, past the orbit, to the upper lip and the wing of the nostril.
m. buccinator · buccinator
The buccinator is the flat muscle of the cheek, stretched parallel to the axis of the mouth; its molar part arises from the maxilla, above the cheek teeth. In the dog it is broad and very thin, with two planes of crossed fibers. It pulls the corner of the mouth backward and laterally and keeps the food between the teeth. It is supplied by the buccal branches of the facial nerve, mainly the dorsal one.
Where: In the cheek, parallel to the axis of the mouth, between the masseter and the corner of the lips.
m. orbicularis oculi · orbicularis oculi
The orbicularis oculi surrounds the opening of the eye; its fibers form the middle, fibromuscular layer of the eyelids and lie next to the tarsus. In the dog, the cutaneous muscle of the face sends a layer toward the lower eyelid that merges with the orbicularis, the malaris muscle. It is supplied by the facial nerve, through the zygomatic branch, the one serving the eyelids and the region of the nose.
Where: In the eyelids, around the opening of the eye.
m. digastricus · digastricus
The digastricus arises from the paracondylar process of the occipital bone and inserts on the ventromedial edge of the mandible. It opens the mouth: when the masticatory muscles relax, it pulls the mandible down. It has two bellies, with different nerve supply, from the trigeminal and from the facial nerve. In Sisson's old nomenclature it appears as the occipitomandibularis, with the same attachments.
Where: From the base of the skull, behind the ear, to the lower edge of the mandible.
mm. auriculares · auricular muscles
The auricular muscles are the small groups of muscles that move the pinna: the rostral group, which contains the scutiform cartilage, a flat plate in front of the ear, and the caudal group. Sisson lists in the dog the scutularis, the anterior auricular muscles, the helicis, the antitragicus and the parotidoauricularis. All are supplied by the facial nerve, which serves the superficial muscles of the head and of the external ear.
Where: Around the base of the ear, with the scutiform cartilage in the front group.