Lecture 2 -- Functional Anatomy of the Proximal Hindlimb

Which spinal nerves provide nerve supply to the hindlimb?

L5, L6, L7, S1, S2

What are the two branches of the Sciatic nerve at the level of the stifle joint?

Tibial and Fibular/Peroneal

What two structures make up the hip joint?

Head of femur and Acetabulum of pelvis

What type of ligaments does the hip joint NOT have?

No collateral ligaments

How is the stability of the hip joint maintained without collateral ligaments?

Round ligament + Surrounding muscle mass

Name the bony prominences of the pelvis that can be palpated.

Dorsal iliac crest

Tuber sacrale

Tuber coxae

Tuber ischium

Palpation of what structure allows location of the hip joint?

Greater trochanter

What are the sources of blood supply to the head of the femur?

1. Vessels from periosteum

2. Vessels from medulla

3. Joint capsule attached round neck

4. Vessels run from neck – head

What movement is associated with protraction?

Hip flexion

What are the hip abductors?

Gluteal muscles

What is the origin and insertion of the Gluteal muscles (superficial, middle, and deep)? What nerve innervates the Gluteal muscles?

O (superficial): From gluteal fascia and sacrotuberous ligament

O (middle): Gluteal surface and lilac crest

O (deep): Shaft of Ileum

I: Greater trochanter

N: Gluteal Nerve

What are the hip adductors?

Gracilis, Adductor , Pectineus and External obturator = GAPE

On which aspect of the hip is 'GAPE' located?

Medial

What is the origin and insertion of the Gracilis muscles? What nerve innervates the Gracilis muscles?

O: Pelvic symphysis

I: Medial tibia + Calcaneus via common calcanea tendon

N: Obturator nerve

How many bellies do Adductors have? What is the origin and insertion of the Adductor muscles? What nerve innervates the Adductor muscles?

O: Pelvic symphysis

I: Medial femur

N: Obturator nerve

What is the origin and insertion of the Pectineus muscles? What nerve innervates the Pectineus?

O: Iliopubic eminence + pubic tubercle via prepubic tendon

I: Medial femur

N: Obturator nerve

What is the origin and insertion of the external obturator muscles? What nerve innervates the External Obturator muscles?

O:Ventral part of pelvis, surrounding the obturator foramen

I: Trochanteric fossa of femur

N: Obturator nerve

From which aspect can we appreciate the trochanteric fossa and intercondyloid fossa?

caudal aspect

What muscles are responsible for hip flexion and limb protraction, and on which aspect are these muscles located?

1. Tensor fascia latae

2. iliopsoas muscle

3. Sartorius

4. Quadriceps - Rectus femoris

Cranial to hip joint

What is the origin and insertion of the Tensor fascia latae muscles? What nerve innervates Tensor fascia latae?

O: Ventral aspect of ilium

I: Fasica latae

N: Gluteal nerve

What is the origin and insertion of the iliopsoas muscles? What nerve innervates Iliopsoas muscle?

O: Ventral aspect of lumber vertebrae & ilium

I: Lesser trochanter of femur (medial aspect)

N: Femoral nerve

How many heads of sartorius muscle? What is the origin and insertion of the sartorius muscles? What nerve innervates sartorius muscles?

2 heads BUT 1 head in cats

• Cranial part
  O: Ilium crest + Thoracolumbar fascia
  I: Distal aspect of femur

• Caudal part
  O: Ventral iliac spine
  I: Tibial tuberosity via patellar ligament
  

BOTH I: Medial femoral fascia around the stifle

N: Femoral nerve

What is the origin and insertion of the rectus fermoris muscle? What nerve innervates rectus fermoris muscle?

O: Ilium

I: Tibial tuberosity via patellar ligament

N: Femoral nerve

How can we appreciate the rectus femoris of the quadriceps?

Cut off biceps fermoris from lateral aspect → Expose the vastus lateralis → Rectus femoris is beneath it

What are the muscles that are responsible for limb retraction and hip extension?

Biceps femoris, semitendinosus, semimembranosus muscles

What is the origin and insertion of the biceps femoris muscle? What nerve innervates biceps femoris muscle?

O (Large cranial head): Sarcrotuberous ligament and Tuber ischium

O (Small caudal head): Tuber ischium

I: Fasica latae + Calcaneus via common calcanean tendon

N: Sciatic nerve

What is the origin of biceps femoris if there is absent of sacrotuberous ligaments in cats?

Solely tuber ischium

What is the origin and insertion of the semitendinosus muscle? What nerve innervates semitendinosus muscle?

O: Tuber ischium

I: Tibia → Calcaneus via common calcanean tendon

N: Sciatic nerve

What is the origin and insertion of the semimembranosus muscle? What nerve innervates semimembranosus muscle?

O: Tuber ischium

I (Short head): Femur

I (Long head): Tibia → Calcaneus via common calcanean tendon

N: Sciatic nerve

What are the different between semimembranosus and semitendinosus?

Semitendinosus has one single belly; semimembranosus has two bellies

Where is the femoral triangle?

Proximal medial thigh

What are its boundaries?

Cranial edge of the pectineus

Caudal edge of Caudal belly of sartorius

Dorsally by iliopsoas

What structure lies within the femoral triangle?

Femoral nerve

Femoral artery

Femoral vein

= Femoral neurovascular bundle (VAN)

Why is the femoral triangle clinically significant?

Anatomical landmark for vascular access + take pulse

Does femoral neurovascular bundle lie superficially or deeply within the femoral triangle?

Superficially

What is the function of tibia?

Weight bearing

Which bone is longer, the tibia or the fibula?

Tibia

Which bone lies laterally?

Fibula

How many centres of ossification of tibia?

4

Proximal end

Tibial tuberosity

Body

Distal end

How many centres of ossification of fibula?

3

Proximal end

Body

Distal end

What are the palpable landmarks in tibia and fibula?

Tibal crest

Medial malleolus (Tibia)

Lateral malleolus (Fibula)

Identify the muscles in the lateral aspect of the thigh.

Identify the muscles in the caudal aspect of the thigh.

Identify the muscles in the medial aspect of the thigh

Which muscles are shown in the picture?

Semimembranosus

Blue: Lateral head of semimembranosus

Orange: Medial head of semimembranosus