Unit 8 - Osteology + Muscles of Proximal PL

What are the attachments of the dorsal sacroiliac ligament?

- Attached to the tuber sacrale and the summits of the sacral spines

- Triangular sheet attached cranially to the tuber sacrala and adjacent part of the medial border of the ilium dorsal to the greater ischiatic notch and ventrally to the lateral border of the sacrum

What does the dorsal sacroiliac ligament blend with ventrally and caudally?

- Blends ventrally with the sacroiliac ligament and caudally with the caudal fascia

What does the ventral sacroiliac ligament surround?

- The sacroiliac joint

The ventral sacroiliac ligament is strong _____________. Where is it located?

- Dorsally

- Located between the ilium and the wing of the sacrum

What are the sublumbar muscles?

- Psoas minor muscle

- Psoas major muscle

- Iliacus m.

- Quadratus lumborum m.

What is the origin, insertion, action and innervation of the psoas minor m.?

- O: Horse = Bodies of T16-L5 vertebrae, vertebral ends of 16th and 17th ribs; Ruminants = Bodies of T12-L5 vertebrae

- I: Psoas minor tubercle on the ilium

- Action: Some flexion of sacroiliac joint; move the pelvis to the side

- Innervation: Lumbar spinal nn.

What is the origin and insertion of the psoas major m.?

- O: Lumbar transverse processes, last two ribs

- I: Lesser trochanter of femur with iliacus

What is the origin and insertion of the iliacus m.?

- O: Sacroiliac surface of ilium, ventral sacroiliac ligaments, wing of sacrum (psoas minor tendon in the horse; body of L6 vertebrae in ruminants)

- I: Lesser trochanter of femur with psoas major

What is the action and innervation of the psoas major m. and the iliacus m.?

- Action: Flex hip and rotate thigh laterally

- Inn: Lumbar spinal nn. and femoral n.

What two muscles join to form the iliopsoas m.?

- Psoas major m.

- Iliacus m.

What is the origin, insertion, action, and innervation of the quadratus lumborum m. in the horse?

- O: Ventral surface of last two ribs dorsally, lumbar transverse processes

- I: Wing of sacrum ventrally, ventral sacroiliac ligament

- Action: Fix the last two ribs and the lumbar vertebrae; bend the lumbar region laterally

- Innervation: Lumbar spinal nn

What is the origin, insertion, action, and innervation of the quadratus lumborum m. in the ruminant?

- O: Bodies of last four thoracic vertebrae, caudal border of last rib, lumbar transverse processes

- I: Transverse processes of succeeding vertebrae, ventral sacroiliac ligaments, wing of ilium ventrally

- Action: Fix the last two ribs and the lumbar vertebrae; bend the lumbar region laterally

- Innervation: Lumbar spinal nn

What are the lateral muscles of the hip and thigh?

- Tensor fasciae latae m.

- Superficial gluteal m.

- Middle gluteal m.

- Accessory gluteal m. (Accessory head of the middle gluteal m.)

- Deep gluteal m.

- Biceps femoris m.

- Gluteobiceps m.

- Semitendinosus m.

- Semimembranosus m.

What is the origin, insertion, action and innervation of the tensor fasciae latae m.?

- O: Tuber coxaeq

- I: Horse - Fascia lata, thus indirectly on the patella; lateral patellar ligament; cranial border of the tibia; Ruminants = Fascia lata and femoral fascia, numerous indirect attachments to the patella and tibia

- Action: Tense the fascia lata, flex the hip joint, extend the stifle joint

- Innervation: Cranial gluteal n.

In which species is the superficial gluteal m. absent?

- Ruminants

What is the origin, insertion, action and innervation of the superficial gluteal m. in the horse?

- O: Tuber coxae, adjacent part of ilium, gluteal fascia

- I: Third trochanter of femur

- Action: Abduct the limb and flex the hip joint

- Innervation: Cranial and caudal gluteal nn

What is the origin, insertion, action and innervation of the middle gluteal m. in the horse?

- O: Aponeurosis of longissimus

lumborum as far cranially as L1 vertebra, gluteal surface of

ilium, sacroiliac and

sacrosciatic ligaments, gluteal fascia

- I: Caudal part of greater trochanter of femur, crest ventral to greater trochanter,

intertrochanteric crest

- Action: Extend the hip joint and abduct the limb; by connection with longissimus lumborum, involved with rearing, kicking and propulsion

- Innervation: Gluteal nn

What is the origin, insertion, and action of the middle gluteal m. in the ruminant?

- O: Sacrosciatic ligament, tuber coxae, gluteal surface of ilium, fascia over longissimus lumborum

- I: Greater trochanter and trochanteric crest of femur

- Action: Extend the hip joint and abduct the limb

What is the origin and insertion of the accessory gluteal m. (accessory head of middle gluteal m.) in the horse?

- O: Ilium

- I: Crest ventral to the greater trochanter

Where is the trochanteric bursa located?

- Located between the tendon of accessory gluteal m. and the cranial part of the greater trochanter

What is trochanteric bursitis?

- The accessory head (accessory gluteal m.) is more fibrous and is prone to tearing. Damage may occur if the horse is not warmed up properly. This causes pain when the horse brings the leg forward; They will be reluctant to take big strides and will attempt to travel sideways

What is the origin and insertion of the accessory gluteal m. in ruminants?

- O: Crest of ilium

- I: Lateral surface of the femur - just distal to the greater trochanter

What is the origin, insertion, action and innervation of the deep gluteal m.?

- O: Ischiatic spin, adjacent body of ilium (and tuber coxae, sacrosciatic and sacroiliac ligaments in ruminants)

- I: Cranial part of greater trochanter

- A: Abduct the thigh and rotate it medially

- Inn: Cranial gluteal n.

What are the two heads of the biceps femoris m. in the horse and their origins?

- Vertebral head: last 3 sacral vertebrae via the sacroiliac ligament, sacrosciatic ligament, gluteal and caudal fascia

- Pelvic head: Tuber ischiadicum

What is the insertion and innervation of the biceps femoris m. in the horse?

- I: Cranial part = Near the third trochanter of the femur, patella; Middle part = Cranial border of tibia, lateral patellar ligament; Caudal part = Tuber calcanei via common calcaneal tendon

- Inn: Caudal gluteal, sciatic and fibular n.

What is the action of the biceps femoris m. in the horse generally? What is the action of each part?

- General action: Extent the limb, as in propelling the body, rearing or kicking, and to abduct the limb

- Cranial part: Extend the stifle and hip joints and abduct the limb

- Middle part: Extend the hip and with semitendinosus may flex the stifle

- Caudal part: Assist in extending the hock

What is the origin, insertion, action, and innervation of the gluteobiceps m. in the ruminant?

- O: Sacrum, sacrosciatic ligament, tuber ischiadicum, ischium near obturator foramen

- I: Lateral patellar ligament, fascia lata, crural fascia, common calcaneal tendon

- Action: Extend the hip and stifle, flex the stifle, abduct the limb and extend the hock

- Innervation: Caudal gluteal and sciatic or tibial nn

What are the two heads of the semitendinosus m. in the horse and ruminant and their origins?

- Vertebral head (Horse): Transverse processes of first two caudal vertebrae, caudal fascia

- Pelvic head (Horse and ruminant): Ventral surface of tuber ischiadicum

What is the insertion, action, and innervation of the semitendinosus m.?

- O: Cranial border of tibia, crural fascia, tuber calcanei by way of common calcaneal tendon

- Action: Extend the hip and hock joints, flex the stifle, rotate the limb medially

- Innervation: Caudal gluteal and sciatic nn

What are the two heads of the semimembranosus m. in the horse and ruminant and their origins?

- Vertebral head (Horse): Caudal border of sacrosciatic ligament

- Pelvic head (Horse and ruminant): Ventral surface of tuber ischiadicum

What is the insertion, action, and innervation of the semimembranosus m.?

- I: Medial epicondyle of femur

- A: Extend the hip joint and adduct the limb

- Inn: Sciatic n.

In ruminants, the semimembranosus m. has a _____________ insertion.

- Wide

What are the cranial muscles of the thigh?

- Quadriceps femoris m.

- Sartorius m.

What are the four parts of the quadriceps femoris m.?

- Rectus femoris

- Vastus lateralis

- Vastus medialis

- Vastus intermedius

What are the attachments of the quadriceps femoris m. in the horse?

- Rectus femoris: from body of ilium topatella

- Vastus lateralis: from lateral border of femur to lateral part of patella and tendon of rectus femoris

- Vastus medialis: from medial surface of femur to medial border of patella, parapatellar fibrocartilage, proximal part of medial patellar ligament, and tendon of rectus femoris

- Vastus intermedius - from cranial surface of femur (proximal to distal third) to patella and femoropatellar joint capsule

What is the action and innervation of the quadriceps femoris m. in the horse?

- Action: Extend the stifle joint; raise the femoropatellar joint capsule during extension of the joint; rectus femoris also flexes the hip joint

- Innervation: Femoral n

What is the origin, insertion, action, and innervation of the sartorius m. in the horse?

- O: Iliac fascia and psoas minor tendon

- I: Medial patellar ligament, tibial tuberosity

- Action: Flex the hip joint and adduct the limb

- Innervation: Saphenous n

What is the origin, insertion, action, and innervation of the sartorius m. in the ruminant?

- O: Cranial head = Iliac fascia and psoas minor tendon; O: Caudal head = Body of the ilium

- I: Crural fascia medial to the stifle, medial patellar ligament(ox)

- Action: Flex the hip joint and adduct the limb

- Innervation: Saphenous or femoral n

What passes between the two heads of origin of the sartorius m. in the ruminant?

- Femoral vessels and nerves

What are the medial muscles of the thigh?

- Gracilis m.

- Pectineus m.

- Adductor m.

What is the origin, insertion, action and innervation of the gracilis m.?

- O: Ventral median raphe of the pelvis and prepubic tendon

- I: Medial patellar ligament (horse and ox), tibia, crural fascia

- Action: Adduct the limb

- Innervation: Obturator n

What is the origin, insertion, action and innervation of the pectineus m.?

- O: Prepubic tendon and cranial border of pubis

- I: Medial border of femur

- Action: Adduct the limb and flex the hip joint

- Innervation: Obturator n

What is the origin, insertion, action and innervation of the adductor m.?

- O: Ventral surface of pubis and ischium, symphyseal tendon

- I: Caudal surface of femur and medial collateral ligament of the stifle joint in the horse

- Action: Adduct the limb, extend the hip joint

- Innervation: Obturator n. (and sciatic and tibial nn. in ruminants)

What are the muscles of the hip joint?

- Gemelli m.

- Internal obturator m.

- Quadratus femoris m.

- External obturator m.

What is the origin, insertion, action and innervation of the gemelli m.?

- O: Horse = Lateral border of the ischium near the ischiatic spine; Ruminants = Ventrolateral part of the ischium and medial surface of tuber ischiadicum

- I: Trochanteric fossa and crest of the femur

- Action: Rotate the femur laterally

- Innervation: Sciatic n

What is the origin, insertion, action and innervation of the internal obturator m.?

- O: Ischiopubic head = Pelvic surface of pubis and ischium around the obturator foramen; Iliac head = Pelvic surface of body of ilium, wing of sacrum

- I: Trochanteric fossa

- Action: Rotate the femur laterally

- Innervation: Sciatic n

In which species is the internal obturator m. absent?

- Ruminants

What is the origin, insertion, action and innervation of the quadratus femoris m.?

- O: Ventral surface of ischium

- I: Caudal surface of femur near lesser trochanter

- Action: Assist in extending the hip joint and adducting the thigh

- Innervation: Sciatic n.; (obturator and sciatic nerves in ruminants)

What is the origin, insertion, action and innervation of the external obturator m. in the horse?

- O: Ventral surface of pubis and ischium and margin of obturator foramen

- I: Trochanteric fossa of femur

- Action: Adduct the thigh and rotate it laterally

- Innervation: Obturator n

What are the two portions of the external obturator m. in the ruminant?

- Regular (extrapelvic) portion

- Intrapelvic portion

What is the origin, insertion, action and innervation of the regular (extrapelvic) portion of the external obturator m. in the ruminant?

- O: Ventrolateral ischium and pubis

- I: Trochanteric fossa with intrapelvic portion and gemelli mm.

- Action: Adduct the limb and rotate it laterally

- Innervation: Obturator n.

What is the origin, insertion, action and innervation of the intrapelvic portion of the external obturator m. in the ruminant?

- O: Pelvic surface of ischium and pubis

- I: Trochanteric fossa with external obturator and gemelli mm.

- Action: Rotate the femur laterally

- Innervation: Obturator n

What is the origin, insertion, action and innervation of the coccygeus m.?

- O: Spine of ischium, medial surface of sacrosciatic ligament

- I: Horse = Transverse processes of caudal vertebrae 1-5; Ruminants = Transverse processes of caudal vertebrae 1-3

- Action: Flex the tail and move it laterally

- Innervation: Caudal rectal n

What are the muscles of the pelvic diaphragm?

- Levator ani m.

- Coccygeus m.

What is the origin, insertion, action, and innervation of the levator ani m.?

- O: Spine of ischium, medial surface of sacrosciatic ligament

- I: Blends with the external anal sphincter

- Action: Fix the anus during defecation

- Innervation: Caudal rectal n