LAB 7 – Review Lab
Lab instructions:
Use this lab to review the axial skeleton, neck, back, thoracic wall and abdominal wall content. Plan to be prepared for the lab and to focus on topics or specific structures that you/your dissection team, wish to gain more understanding of, particularly with the assistance of instructors. Below, we have provided the list of links to lab review videos and a compilation of the terms lists, for Sections 2 and 3.
Review Videos
Carnivore skull osteology – 38 min, ignore details on foramina for now
Ungulate skull osteology – 17 min, ignore details on foramina for now
Cow cervical vertebrae osteology – Watch until 2:40
Horse nuchal ligament in motion – 15 sec
Ungulate thoracic osteology – 5 min
Terms
Print optimized terms list (Missing Lab 6 Terms, will try to update)
Lab 1
Regions and spaces of the Skull | |||
Osteology |
Comments | Species Differences | |
Cranium | Part of skull that encloses the brain. | ||
cranial cavity | Created by the bones of the cranium, brain resides in this cavity | ||
calvaria | Roof of the cranium. | ||
Face (facies) | Part of skull that encloses respiratory and alimentary tracts |
Bones of the Skull | |||
Osteology |
Features |
Species Differences/identify in |
|
Bones of the cranium | |||
Frontal bone | Cornual process | Ruminant | |
Parietal bone | External sagittal crest | Carnivore, horse | |
Temporal lines | Horse, ruminant | ||
Interparietal bone | |||
Occipital bone | External occipital protuberance | ||
Occipital condyles | |||
Paracondylar processes | |||
Nuchal crest | |||
Foramen magnum – where brainstem exits cranial cavity to continue as spinal cord | |||
Basisphenoid bone | |||
Presphenoid bone | |||
Pterygoid bone | |||
Temporal bone | Squamous part | Zygomatic process | |
Mandibular fossa | |||
Retroarticular process | |||
Tympanic part | Tympanic bulla | Contains tympanic cavity that is subdivided in cat by septum bulla | |
External acoustic meatus | |||
Petrous part | Mastoid process | ||
Ethmoid bone | Cribriform plate | ||
Vomer | Singular bone of skull on ventral midline, supports nasal septum | ||
Bones of the face | |||
Maxilla | Facial crest | Horse | |
Facial tuberosity | Ruminant, pig | ||
Nasal bone | |||
Nasoincisive notch between nasal and incisive bones | |||
Incisive bone | |||
Lacrimal bone | |||
Palatine bone | |||
Zygomatic bone | Forms zygomatic arch along with portions from temporal and frontal bones | In carnivore, pig: connects to orbital ligament. | |
Mandible | Body | ||
Ramus | |||
Coronoid process | |||
Condylar process | |||
Angular process | Carnivore | ||
Os rostrale (rostral bone) | supports the snout | Pig |
Additional features and joints of the Skull | |
Feature | Description/Species Difference |
Nasal aperture | bony opening to nasal cavity |
Nasoincisive notch | created by nasal and incisive bones, prominent in ungulates. |
Orbit | Orbital margin – consists of multiple bones combining to form rim. |
Orbital ligament – carnivore, pig; bridges frontal to zygomatic bone, usually fibrous, may ossify in mature cats to form a complete bony rim. | |
Zygomatic arch | Formed by zygomatic, temporal and sometimes frontal bones; species variation |
Pterygopalatine fossa | caudoventral to orbit, skull region between maxilla and pterygoid process of basisphenoid bone |
Temporomandibular joint | synovial joint |
Intermandibular articulation | (= mandibular symphysis), |
Hyoid apparatus |
|
Bone | Species Difference/comments |
Tympanohyoid (not seen) | joins stylohyoid to temporal bone |
Stylohyoid | Divides guttural pouch compartments in horse |
Epihyoid | Carnivore, ox (vestigial in horse) |
Ceratohyoid | Surgical removal to treat temporohyoid osteoarthropathy in horse |
Basihyoid | |
Lingual process | Horse and ox |
Thyrohyoid |
Vertebral formula | |||||
Cervical (C) | Thoracic (T) | Lumbar (L) | Sacral (S) | Caudal (Ca) | |
Carnivore | 7 | 13 | 7 | 3 | 20 |
Horse | 7 | 18 | 6 | 5 | variable |
Ruminant | 7 | 13 | 6 | 5 | variable |
Pig | 7 | 14/15 | 6 | 4 | variable |
Osteology of the vertebral column | |
Osteology | Features and comments |
All vertebrae |
Body (except C1, which has a ventral arch instead) |
(Dorsal) Spinous process | |
Transverse process | |
Articular process | |
Vertebral foramen | |
Arch (consists of two pedicles and a lamina) | |
Vertebral canal | |
Intervertebral foramen – for spinal nerves to exit vertebral canal. | |
Cervical vertebrae | |
C1 = Atlas | Wings of atlas (= transverse processes) |
Transverse foramen – for pathway of vertebral vessels and nerve. | |
Lateral vertebral foramen – for exit of C1 spinal nerve | |
C2 = Axis | Dens |
Transverse foramen | |
C3-C7 | Transverse foramen (except C7) |
Ventral lamina of C6 (sled runners) | |
Thoracic vertebrae |
Costal fovea |
Anticlinal vertebra | |
Lumbar vertebrae |
As above for all vertebra |
Sacral vertebrae (sacrum) |
Sacral foramina – for exiting of branches of sacral spinal nerves. |
Auricular face – articulates with ilium (to form sacroiliac joint) | |
Promontory – ventral border of cranial base of sacrum | |
Caudal (coccygeal) vertebrae |
Hemal arches (V shaped fusion of processes on ventral aspect of caudal vertebra, bovine and carnivore. |
Features of the vertebral column |
||
Feature | Landmark | Species Difference |
Atlanto-occipital joint |
the ‘yes’ joint | |
Dorsal atlanto-occipital ligament (membrane) | ||
Atlantoaxial joint | the ‘no’ joint | |
Dorsal atlantoaxial ligament | ||
Transverse ligament of atlas | Examine in carnivore models. | Present in carnivore and pig. |
Intervertebral disc | Anulus fibrosus | |
Nucleus pulposus | ||
Supraspinous ligament | Between consecutive tips of spinous processes of thoracic and lumbar vertebrae. | |
Yellow ligament | between adjacent vertebral arches, dorsal margin. | |
Intercapital ligament | between paired rib heads | for ribs 2-10 in the dog. |
Lab 4
Muscles/structures |
||
Epaxial mm. | Iliocostalis system | |
Longissimus system | ||
Transversospinalis system | ||
Semispinalis capitis m. | Carnivore, horse, ruminant | |
Splenius | all; has 2 parts in ungulates | |
Hypaxial mm. | Longus capitis m. | |
Longus colli m. | ||
Nuchal ligament | Funiculus nuchae | Dog, horse, ruminant |
Lamina nuchae (paired) | Horse, ruminant | |
Lamina nuchae (un-paired) | Ruminant – identify in calf | |
Bursa | Supraspinous bursa | Horse – often hard to specifically identify but let’s have a good crack at it. |
Cranial (and caudal if present) nuchal bursa | Horse – don’t look for these but be aware of location | |
Rectus capitis dorsalis mm. | Horse, ruminant | |
Obliquus capitis caudalis m. | Horse, ruminant |
Muscle attachments and actions |
||
Muscle/structure | Attachments | Action |
Iliocostalis system | Overlapping fascicles from ilium to rib 1 | Extension and lateral movement of vertebral column |
Longissimus system | Overlapping fascicles from ilium to skull | Extension and lateral movement of vertebral column |
Transversospinalis system | Overlapping fascicles from sacrum to skull | Extension and lateral movement of vertebral column |
Semispinalis capitis | Thoracic vertebrae to skull | Extend head and neck, lateral flexion of neck |
Splenius | Spinous processes T1‐3 and median raphe to skull | Extend and raise head and neck, lateral flexion of neck |
Longus colli | Ventral vertebral bodies and transverse processes T6 to C1 | Flex neck |
Longus capitis | Transverse processes cervical vertebrae to skull | Flex atlanto‐occipital joint and draw neck ventrally |
Lab 5
Thorax osteology and arthrology |
|
Thoracic vertebrae |
Canine 13, Ruminant 13, Pig 14-15, Horse 18 |
(Dorsal) spinous process | |
transverse process | |
cranial/caudal articular processes | |
body | |
arch (consisting of two pedicles and the lamina) | |
costal fovea | |
anticlinal vertebra (T11) in canine | |
Ribs – paired. Same number as thoracic vertebrae | Head |
Neck | |
Tubercle | |
Body | |
Costochondral junction | |
Costal cartilage | |
Costal arch | |
Intercostal space | |
Sternum – sternebrae and number |
carnivore 8, horse and ruminant 7, pig 6 |
Manubrium | |
Xiphoid process | |
Thoracic inlet | define boundaries |
Thoracic outlet | define boundaries |
Thoracocentesis |
define typical location as described |
Thoracic wall myology and comments |
|
Serratus dorsalis mm. | cranial and caudal divisions |
Scalenus m. | multiple slips or divisions |
External intercostal mm. | |
Internal intercostal mm. | |
Rectus thoracis m. | |
Transversus thoracis m. | Learn on a model at this time |
Lab 6
Abdominal Muscles | |
External abdominal oblique m. | |
Internal abdominal oblique m. | |
Transversus abdominus m. or Transverse abdominal m. | |
Rectus abdominis m. |
Abdominal wall/muscle structures | |
Linea alba | |
External rectus sheath | |
Internal rectus sheath | |
Superficial inguinal ring | |
Inguinal canal | define (dissected later) |
Deep inguinal ring | not identified yet, understand as part of inguinal canal anatomy |
Flank | Ruminant, horse |
Paralumbar fossa | Ruminant, horse |
Lumbar vertebrae | All, note number and that L1, L6 in live ox are typically not palpable. |
Subiliac lymph nodes | Ungulates only |
Elastic abdominal tunic | Horse, ruminant – yellowish appearance |
Deep circumflex iliac vessels | Horse flank |