Small Animal Anatomy Pelvic Limb

os coxae

3 major bones fused together:

1. illium

2. ischium

3. pubis

-flat bones

-pelvic symphysis- cartillaginous joint between left and right os coxae

sacroilliac joint

joint of stability between sacrum and the illium

rump region

body region of the pelvis

thigh region

region from the hip joint to to ginual joint

-femur found there

crus region

"leg"

-stifle to tarsal joints

-fibula and tibia

pes regoin

hindpaw region

-tarsus

-metatarsus

-phalanges

-weight bearing digits: 2-5

-variable dewclaw

coxal joint [hip joint]

- between head of femur and acetabululum

-ball and socket

-full range of motion

ginual [stifle] joint

-femur and tibia + patella

tarsal joints

joints between tarsal bones

digital joints

3 joints/ digit

-proximal: metatarsophalangeal

-proximal and distal interphalangeal joints

hip joint flexor angle

cranial surface

ginual joint flexor angle

caudal surface

tarsal joints flexor angle

dorsal surface

digital joint flexor angle

plantar aspects

illium

most cranial bone

2 parts:

1. wing

-illiac crest: cranial edge

-tuber sacrale- dorsal part of the wing between 2 bumps, near sacrum

-tuber coxae- ventral part of wing between 2 bumbs

-gluteal surface: concave surface of the lateral wing

-sacropelvic surface- where sacroilliac joint will sit, medial wing

-auricular surface- 2 smooth surfaces on the sacropelvic surface

-area for rectus femoris- bump cranial to the acetabulum

-arcuate line: medial ridge

2. body

-greater ischiatic notch: caudal half of dorsal border that is concave

Ischium

caudal part of the os coxae

1. Body: caudal to ascetabulum

-ischiatic spine

-lesser ichiatic notch

2. Table of the ischium: flat horizontal portion

3. ischiatic tuberosity: thick caudolateral margin

-ischiatic arch: between both tuberosities, where external genetalia will be

4. ramus- medial "branch"

pubis

"L shaped"

1. body of pubis: at the angle

2. cranial ramus

-illiopubic eminence: bump that projects from cranial border

-pecten- roughened cranial border

-obturator sulcus: groove for obturator nerve

3. caudal ramus

acetabulum

where head of femur joins

- deeply concave

-acetabular notch: gap in circumference of articular surface

-acetabular fossa: formed by ischium and acetabular bone

obturator foramen

A large hole that's formed as the pubic bone fuses with a part of the ischium. It's the largest foramen in the body.

femur

thigh bone, long bone

1. head

2. neck

3. body

4. condyles (medial and lateral)

head of femur- parts

1. fovea capitis- shallow fossa

2. greater trochanter

3. lesser trochanter

4. third trochanter

5. intertrochanteric crest

6. trochanteric fossa

dital extremities of the femur

1. trochlea- patella rides in

2. condyles

3. intercondylar fossa

4. medial and lateral supracondylar tuberosities

5. epicondyles

6. extensor fossa- between lateral condyle and crest of trochlea

tibia

larger of the lower leg bones

1. proximal end

2. body

3. distal end- coclea and medial malleolus

proximal tibia features

1. medial and lateral condyles- 2 flattened smooth surfaces on top

2. intercondylar eminence- two small bumps

3. cranial intercondylar area

4. caudal intercondylar area

5. popliteal notch- caudal and between two condyles

6. tibial tuberosity- cranial process

7. cranial border- ridge that runs distal to tibial tuberosity

8. extensor groove of tibia- small smooth groove at the junction of the lateral condyle and the tibial tuberosity

fibula

1. head- no grooves

2. body

3. lateral malleolus- has deep lateral and caudal grooves

tarsal bones features

proximal row: two large bones

distal row: three bones

-fourth bone is "two stories": causes gap between proximal and distal rows

- central tarsal bone

tarsal bones- proximal row features

1. calcaneus- large proximal projection, lateral bone

-tuber calcanei: project proximally and caudally

-sustentaculum tali: bony process on medial surface that props up the talus

2. talus- trochlea (attaches to coclea or tibia)

tarsal bones distal row features

consists of bones 1-4

-tarsal bone 4 connects with metatarsals 4 and 5

metatarsal bones

base- proximal

body

head- distal

-numbered 2-5

digits of hindpaw

phalanges + sesamoid bones

-similar to forepaw

where can you find the most movement in the tarsal joints?

between the coclea of the tibia and the trochlea of the talus. The tarsocrural joint

name the muscle groups of the pelvic limb

1. Caudal thigh

2. Medial thigh

3. Lateral pelvis [rump]

4. Caudal hip

5. Cranial Thigh

6. Craniolateral leg

7. Caudal leg

major action of the caudal thigh group

extend the hip

major action of the medial thigh

adduct the limb, extend hip

major action of the lateral pelvis muscles

extend hip joint, rotate limb medially, abduct limb

major action of the caudal hip muscles

rotate limb laterally- opposes action of the lateral pelvis muscles to keep limb on the sagittal plane

major actions of the cranial muscles of the thigh

necessary to bear weight, flex hip joint

major action of the muscles of the craniolateral leg

flex tarsal joints and extend digital joints (flexing foot)

major action of the caudal muscles of the leg

extend tarsal joints, flex digital joints (pointing toe)

major origins and insertions of the caudal thigh muscles

O: ischiatic tuberosity

A: tuber calcanei (biceps and semitendinosis); biceps femoris- fascia lata to patella and cranial tibia; semitendiosus- distocranial tibia; semimembrinosus- distocaudal femur and medial condyle of tibia

major origins and insertions of medial thigh muscles

O: illium, pelvic symphysis

I: patella, cranial tibia, tuber calcanei (gracillis), caudal femur (pectineus)

lateral pelvis muscle origins and insertions

O: surfaces of the pelvis and sacrum

I: trochanters of the pelvis, lateral femoral fascia (tensor fasciae latae)

major caudal hip muscle origins and insertions

O: inner and outer surfaces of ischium

I: femur

major cranial thigh origins and insertions

O: femur and illium; lumbar vertebrae and illium (iliopsoas)

I: tibial tuberosity; lesser trochanter