Module 4: Bones-Appendicular-Forelimb Flashcards
Clavicle
Present in some mammals, may be vestigial/absent
May be useful for species ID
Fish have, turtles have in plastron, birds-wishbone
Ribs
12 per side-24 total, sometimes more
First 7 articulate w sternum (true ribs)
8,9,10 articulate via common cartilage (false ribs)
11- do not articulate (floating ribs)
Vary according to species
Head articulates w body of 2 vertebrae (double articular facet on head)
Caudal ribs have single articular facet
Neck-between head and tubercle; articulates with transverse process
Shaft-flat segment, broadens towards center then tapers towards eternal end
Width increases then decreases cranial to caudal
Costal groove-houses artery, vein, nerve=sharp caudal border
Cranial border-rounded and thicker
Head articulates with 2 thoracic bodies, tubercle articulates with transverse fovea of thoracic vertebra of same #
Anatomical order of ribs
Superior/cranial ribs have acute/right angle between head and tubercle
Central ribs have roughly straight line
Inferior/caudal ribs have head and tubercle at angle to each other
Ribs “fit” within each other
Curves follow each other-if one rib margin “dives” steeply from other, do not go together
Siding ribs
In anatomical position, head dorsal and sternal end is ventral.
Tubercle dorso-medial and head points ventro-medial
Thicker border-cranial
Thinner border-caudal
Cranial border can be thinner in more cranial ribs, costal groove is still evident on caudal border-will help with orientation and siding
Head and sternal ends relatively easy to side, isolated shaft pieces can be more difficult
Differences in human vs other mammals limb bones
Mammals-more sculpted, joints in particular-more ridges, tuberosities, notches
Scapula
Dorso-lateral surface of mammals
Elongated for muscle attachments
Subscapular fossa
Medial/internal surface of the scapula
Concave
A few ridges, oblique ridges for attachment of subscapularis muscle and tendons
Scapular spine
Dominates lateral/external surface of scapular; divides the bone into cranial (supraspinous fossa) and caudal (infraspinous fossa) halves
Some species have larger infraspinous fossa, some have secondary smaller spine dorsal to scapular spine
Spine points toward Glenoid fossa
Glenoid fossa
Articular joint for the humerus
Ovoid to rounded
Shallower than the acetabulum
Supraglenoid fossa
Superior to the Glenoid fossa
Attaches to biceps brachii
Infraglenoid tubercle
Inferior to the fossa
Attaches to the triceps brachii/teres minor
Acromion process
Dorso-laterally from the spine to the side of the Glenoid fossa
Can be well developed in some species and reduced in others
Coracoid process
Cranial to the Glenoid fossa
More developed in some species than others
Scapular notch
Posterior to the coracoid process; more notch-like in some species than others
Cranial border
Thickens as it progresses medially/dorsally
Both cranial and medial/dorsal borders tend to be thinner than the caudal border, which can be buttressed in some species
Cranial and dorsal borders meet at the cranial angle and the dorsal and caudal borders meet at the caudal angle
Siding the scapula
Glenoid fossa is always lateral and spine on external surface
Spine increases in size/thickens and develops flares from lateral to medial side
When fossae are uneven, smaller (supraspinous) is cranial and larger is caudal
Caudal border-thickest border
Looking at spine with caudal border down, Glenoid fossa is on the side the bone belongs (fossa to the right=right scapula)
When looking at the Glenoid fossa, coracoid processes curve more medially/towards the internal surface
With coracoid process up, curves toward the side the bone belongs, or acromion process is on opposite side from where the bone belongs
Humerus
Humeral head articulates with Glenoid fossa
Head is rounded and allows for rotation, more ovoid in species that require less rotation
Head oriented more posteriorly in quadrupeds for articulation with downward facing scapula
Lesser tubercle is small projection ventro-medial to head and greater tubercle is large projection dorso-lateral to the head. Between-intertubercular sulcus/bicipital groove
Shaft below tubercles
Nutrient foramen mid-shaft on posterior surface and opens superiorly (blood vessel would run down into foramen)
Proximal half of shaft is more ovoid cranio-caudally in cross section while distal half is more rounded to slightly ovoid medio-laterally in cross section
Deltoid tuberosity on shaft on lateral aspect
Humerus pt. 2
Distal aspect=3 fossae; posterior-olecranon: largest and accommodates olecranon process of ulna, can have perforation/septal aperture; anterior-coronoid:on more medial side for coronoid process of the ulna; lateral of anterior surface-radial: for head of radius
On distal, joint that articulates w radius/ulna. Rounded eminence on lateral side: capitulum for articulation with radius and spool-shaped structure on medial side: trochlea for articulation with ulna
Borders of these flanked by lat/med epicondyles, medial more prominent
Siding the humerus
At cranial side of shaft w head away from you, w head up, intertubercular groove is on side bone belongs, deltoid tuberosity opposite, muscle ridge swoops down from deltoid tuberosity to medial epicondyle or to side bone belongs
At caudal aspect w head facing you, medial epicondyle elevated in comparison to lat. medial epicondyle/border thicker than lat. at posterior aspect, thinner side is side where bone belongs. On posterior aspect, depression above olecranon fossa slopes down laterally/towards the side bone belongs while trochlea slopes away
Radius
& ulna fuse in adults mostly
Radius compressed cranio-caudally. Superior aspect is head-articulates with capitulum. Depression in head-fovea capitis.
Head-ovoid and sometimes very sculpted. Rotation non-essential.
Large head-articulates w both condyles->head w 2 facets, medial larger
On caudal aspect of head is articular circumference for articulation w ulna. Radial tuberosity is inferior to head on medial border, biceps brachii inserts on this
Radius cont.
Slightly cranial/anterior to ulna, interosseus crest on medial to posterior/caudal surface. Cranial side of shaft convex and smooth, caudal slightly concave and roughened. Nutrient foramen on medial to posterior surface, opens inferiorly. Shaft of radius consistent through length then flairs at distal end
Distal end articulates with ulna and 2 carpals. Caudal surface is ulnar articulation. Bump on bone opposite this articulation is medial styloid process. Cranial surface-3 grooves, medial:small/oblique w tendon for abductor digiti I longus. Middle groove: wide and vertically oriented and houses extensor carpi radialis, lateral groove: wide, indistinct, vertically oriented and houses common digital extensor
Siding radius
Looking at head of the radius with notch down or interosseus crest up, bump of bone/slightly larger side is the side the bone belongs/larger articular surface is on the side it belongs. Divided articular heads-at with ridge of bone between facets going up or interosseus crest down, larger facet on the side.
When looking at interosseus crest with head up, styloid process on opposite side bone belongs and crest is slightly to side it belongs.
Looking at distal articular surface w interosseus crest down, elevated bone of styloid process is on the side.
For artiodactyla (even toed ungulates), looking at distal articular surface with interosseus crest down, slightly convex articular surface with ridge to side the bone belongs.
Ulna
Superior aspect dominated by olecranon process, trochlea (semilunar notch) articulated with trochlea of humerus. Anterior has coronoid process-medial and lateral in Somme species-medial larger. Radial notch is articulation for head of radius. Radial head and notch form floor of semilunar notch. Below medial coronoid process is ulnar tuberosity, insertion for biceps brachii
Interosseus crest on lat/ant surface of shaft and roughened
Nutrient foramen is also lat/ant and opens dismally
Distal aspect tapers to lateral styloid process
Ulna
Superior aspect dominated by olecranon process, trochlea (semilunar notch) articulated with trochlea of humerus. Anterior has coronoid process-medial and lateral in Somme species-medial larger. Radial notch is articulation for head of radius. Radial head and notch form floor of semilunar notch. Below medial coronoid process is ulnar tuberosity, insertion for biceps brachii
Interosseus crest on lat/ant surface of shaft and roughened
Nutrient foramen is also lat/ant and opens dismally
Distal aspect tapers to lateral styloid process
Siding the ulna
Looking at semilunar notch, coronoid projects to side it belongs. Radial notch is opposite side.
At head of olecranon, with semilunar notch up, head leans away from side it belongs
On distal aspect, looking at roughened side with articular surface, styloid process leans to side bone belongs, at smoother side process leans away
Forelimb
Familiarity with changes in shape of shafts and orientation of nutrient foramen will help with determining which end is cranial vs caudal in shaft pieces, which can allow you to side them
To help with remembering which direction nutrient foramen open, look at dog lying down. When looking from the front, you can look into nutrient foramen on long bone shafts, or can open towards you.
Carpals/metacarpals/phalanges
Less frequently collected in archaeological situations. Reference manuals rarely detail these.
Sesamoid bones also common in many species, appear rounded and do not have any articulations, form in tendon at stress points for extra leverage.
Particularly at metacarpophalangeal joints
In dogs, often additional sesamoid between intermedioradial and Distal I. Also 2 proximal and 1 dorsal at each meacarpophalangeal joint of forepaw and frequently at prox and intermediate phalangeal joint
Carpals
Up to 8: radial/scaphoid, intermediate/lunate, ulnar/cuneiform, accessory/pisiform, distal I/trapezium, distal II/trapezoid, distal III/magnum, Distal IV/unciform
Radial and intermediate can fuse: intermedioradial or scapholunate
Distal carpals can also fuse
1st distal carpal smallest, 4th largest
More tightly articulated, less mobility
Radial
Largest carpal bone. Large convex fact and on concave side, 3 facets that look like M/W
Siding-looking at convex side with flatter side on thumb, process/nubin up and point to side bone belongs to
Ulnar
Next largest. Z shaped. One side concave, other convex
Siding-looking at convex side, bone looks like duck, beak points away from side of bone.
Accessory
Has a bulbous end and concave facet at other end
Siding-with bulbous “head” up and bone laying on tape so it doesn’t rock, styloid to the side it belongs
Distal carpals
Distal carpals 1-3 progressively larger
Distal carpal 4 is “pyramid” with large concave facet on bottom
Siding-when pyramid is upright and bulbous projection is towards you, bone leans to side/more inclined slope is the side it belongs.
Metacarpals
Often 5, but reduced in various species, some only 1. Roman numerals
1st is shortest, 3rd and 4th longest
Base at proximal end, shaft, then head at distal end
Flatter in their cross section than metatarsals
Flatter surface is plantar
Metacarpals shorter/thicker than metatarsals
Head often have raised ridge in center and bases vary
Cow and deer have anterior and posterior groove, anterior deeper than posterior, and deeper on metatarsal than metacarpal
Siding metacarpals (dog/coyote)
When looking at base, pinched/plantar surface is down
Hold dorsal surface up and flat
MC 11 D shaped shaft with medial surface flatter and lateral more rounded, base w shaped. Looking at dorsal, longer side of W is the side, at base forms swoosh/moon towards side it belongs/triangle points to side
MC III has slight W to slightly concave base and from medial/lateral side, very U-shaped. At base, bottom tapers to point and leans toward side
MC IV has convex base at shaft, medial side has slight process. Lateral side distinct L/backwards J facet. At dorsal surface, L facet on side, at base, bottom away from side
MCV J shaped facet on medial side and bony prominence and no articulation on lateral side or side bone belongs
Siding metacarpals (cow, deer, horse)
Looking at base with flat side down, base is pinched/smaller articular facet on side it belongs
Phalanges
Proximal, intermediate and distal row totaling 14 (thumb has only proximal and distal)
Can be reduces as number of toes/fingers is reduced
Get smaller from proximal to distal
Also comprised of base at proximal end, shaft, and head at distal end
Head have 2 lobes and bases have a 2 lobed indention to accommodate head
Distal phalange often has ungual process-claw/hoof
Sesamoid bones common. Many have 2 on palmar surface of metacarpal-phalangeal joint and/or one sesamoid on velar surface of MC-P or interphalangeal joints
