Equine Anatomy SG 1

  1. What is the vertebral formula of the horse?
    C7 T18 L6 S5 Cd~15
  2. What is the relationship of the cervical vertebrae to the dorsal midline?
    Gently sloping backwards "s" curve
  3. What are the anatomical differences of the nuchal ligament in the horse and the dog?
    • Dog (1 component) - from spine of T1 to spine of axis
    • Horse (2 components) - funiculus nuchae (cord-like) from skull to spines of thoracic vertebrae of withers where it becomes continuous w/supraspinous ligament; lamina nuchae (sheet-like) from spines of T2-3 to spines of C2-6
  4. Where are the bursae located in relation to the nuchal and supraspinous ligaments?
    • Cranial nuchal bursae - between the arch of the atlas (C1) and the funiculus nuchae
    • Caudal nuchal bursae - between the spine of the atlas (C2) and the funiculus nuchae
    • Supraspinous bursa - over the whithers at the junction of the funiculus nuchae cranially and the supraspinous ligament caudally
  5. What clinical conditions involve these bursae?
    • Poll evil - inflammation/infection of cranial nuchal bursa
    • Fistulous withers - inflammation/infection of the supraspinous bursa
  6. What condition affects the cervical vertebrae causing compression of the spinal cord and ataxia in horses?
  7. Where is the crest? What is the composition of the tissue in this area?
    Located on the dorsal midline of the neck; composed of fat
  8. Identify the topographic position of the wing of the atlas
    Can be palpated near the base of the poll
  9. Identify the superficial muscles of the ventral surface of the neck
    • Cutaneous colli
    • Brachiocephalicus - cleidomastoideus + cleidobrachialis
    • Omotransversarius
    • Sternocephalicus
    • Sternothyrohyoideus - sternothyroideus + sternohyoideus
  10. Identify the deep muscles on the ventral aspect of the neck
    • Omohyoideus
    • Longus capitis
    • Longus colli - cervial part + thoracic part
    • Scalenus
  11. Identify the superficial muscles on the lateral surface of the neck
    • Trapezius - trapezius cervicis + trapezius thoracis
    • Rhomboideus - rhomboideus cervicis + rhomboideus thoracis
    • Splenius
    • Serratus ventralis - serratus ventralis cervicis + serratus ventralis thoracis
  12. Identify the first deep layer of muscles on the lateral aspect of the neck
    • Semispinalis capitis
    • Longissimus capitis/Longissimus atlantis (fused at origin)
    • Longissimus cervicus
  13. Identify the second deep layer of muscles on the lateral aspect of the neck
    • Multifidus cervicis
    • Intertransversarii cervicis
    • Spinalis system
  14. What is the poll? Identify the cranial and caudal oblique muscles
    • The poll is the back of the head
    • Obliquus capitis cranialis
    • Obliquus capitis caudalis
    • Rectus capitis muscles (deep to obliques)
  15. How many cervical nerves are present in the horse?
    8 pairs
  16. The accessory nerve has a dorsal and ventral branch; which cervical muscles are innervated by each?
    • Dorsal branch - trapezius, brachiocephalicus, omotransversarius
    • Ventral branch - sternocephalicus
  17. Where are the transverse nerve of the neck and the cervical branch of the facial nerve located?
    • Transverse nerve of the neck - branches of C2 & C3; innervates mandible
    • Cervical branch of facial nerve - runs with external jugular vein
  18. Identify the origin of the phrenic nerve and brachial plexus
    • Phrenic n. - ventral branches of C5, C6, C7
    • Brachial plexus - ventral branches of C6-8, T1 & 2; deep to scalenus m.
  19. Identify the major vessels supplying the cervical musculature
    • Deep cervical artery
    • Vertebral artery
  20. Identify the superficial and deep cervical lymph nodes
    • Superficial cervical lymph nodes - located near the deep aspect of the brachiocephalicus
    • Deep cervical lymph nodes - run along the trachea
    • Cranial - around the thyroid gland
    • Middle - middle of neck
    • Caudal - thoracic inlet
  21. Which muscles show a degree of fusion in the cervical region?
    • Brachiocephalicus
    • Sternothyrohyoideus
    • Omohyoideus
    • Longissimus capitis/Longissimus atlantis
  22. What is Viborg's triangle? Where are its borders?
    • Surgical landmark for the gutteral pouch and related retropharyngeal lymph nodes
    • Cranial border - ramus of mandible
    • Ventral border - linguofacial vein
    • Dorsal border - tendon of sternocephalicus
  23. What is the jugular groove? What are the borders of this groove?
    • Location of the jugular vein
    • Dorsal border - cleidomastoideus
    • Ventral border - sternocephalicus
    • Deep border - omohyoideus
  24. What is the significance of the omohyoideus in the horse?
    "Protects" the common carotid a. from deep venipuncture by acting as a barrier between the carotid a. and jugular v.
  25. What is the relationship of the trachea and esophagus through the cervical region?
    The esophagus begins at the pharynx dorsal to the trachea, then moves to the left side at the level of C4, dorsal to trachea at thoracic inlet
  26. What are the borders of the lateral pectoral groove? Which major venous structure is found in this groove?
    • Borders: cleidomastoideus + descending pectoral
    • Cephalic v. + deltoid br. of superficial cervical a.
  27. What are the borders of the median pectoral groove?
    Between left and right descending pectoral mm.
  28. Which structures are contained in the carotid sheath?
    • Common carotid a.
    • Vagosympathetic trunk
    • Recurrent laryngeal n.
    • Internal jugular v. (variables)
  29. Classify the dorsal and ventral spinal nerve roots as sensory or motor structures. Are the dorsal and ventral branches of the spinal nerve sensory or motor or mixed?
    • Dorsal spinal nerve root - sensory information to the cord
    • Ventral spinal nerve root - motor information from the cord
    • Dorsal and ventral branches of spinal nerve - mixed
Card Set
Equine Anatomy SG 1