Hindlimb - Blood, Lymph and Nerve Supply

Reminder: what nerves supply the hindlimb and produce the lumbosacral plexus?

• Spinal nerves

• L5, L6, L7, S1, S2.

• Dorsal branches - dorsal structures

• Ventral branches - lumbosacral plexus

• Emerging peripheral nerves to hindlimb: (are all paired)

• Gluteals

• Obturator

• Femoral

• Sciatic - tibial

- fibular / peroneal

Describe the route and function of the gluteal nerve.

• Route:

• Runs over dorsal surface body of ilium, is very short

• Function:

• Gluteal muscles

• Hindlimb abductors - in the dog

• (Horse - hind limb retractor / hip extensor)

• No areas of cutaneous sensation

• Gluteal nerve is a motor nerve, contributing to movement

Describe the route and function of the obturator nerve.

• Route:

• Passes through obturator foramen

• Short route to medial thigh region

• Function:

• Supplies movement to the Hindlimb adductors:

  • Gracilis

  • Adductor

  • Pectineus

  • External obturator

No areas of cutaneous sensation

What are important clinical considerations for the obturator nerve. 

• Clinical considerations:

• Problem in cows if damaged during parturition by:

• Oversized calves - as it passes through pelvic cavity, they may damage the nerve

• Cows stand up hind end first, will do the splits and fall

  • Down cow ('Doon coo')

  • TVA fig 31-12

• Not a problem in horses:

• No oversized foals, as we do in cows

• Stand up front end first

Describe the route and function of the femoral nerve.

Route: Short route to cranial thigh

• Function:

• Cranial thigh muscles, AND provides cutaneous sensation to the medial aspect of the limb

• Illiopsoas

• Sartorius

• Quadriceps (all heads)

• Hip flexors / limb protractors

• Stifle extensors

AND has a branch called the saphenous branch

How does the femoral nerve provide cutaneous sensation?

• Cutaneous sensation:

• Saphenous branch - running down the full length of the limb

• (Femoral triangle)

What nerve is associated with the patellar reflex?

• Local reflex involving the femoral nerve

• Patellar ligament - quadriceps - extension of stifle

Damage to the femoral nerve might result in?

Damage:

• Cannot extend stifle

• cannot weight bear

• no compensation

• Loss of patellar reflex → key indicator that damage has occured

Describe the route and function of the sciatic nerve.

• Route:

• Runs over dorsal surface body of ilium

• Passes caudal to hip

• Runs deep to biceps femoris

• Function:

Motor nerve to:

• Caudal thigh muscles:

• Biceps femoris

• Semitendinosus

• Semimembranosus

• Hip extensors / limb retractors

• Stifle flexors

How does the sciatic nerve branch?

• What are the routes and functions of these branches?

Two branches:

Tibial Nerve - runs on caudal/plantar aspect of the limb

• Function: provides motor and cutaneous sensation

• (Cutaneous - caudal/plantar sensation)

• Caudal tibial muscles:

• Gastrocnemius

• Superficial digital flexor

• Deep digital flexor

• Hock extensors

• Digital flexors

• Peroneal / fibular Nerve (Branch of Sciatic)

• Function: cutaneous sensation of dorsal and cranial aspect, lateral thigh

• Cranial tibial muscles

• Cranial tibial

• Peroneus group

• Long digital extensor

• Hock flexors

• Digital extensors

What may cause sciatic nerve damage?

• Damage may cause a loss of supply to which structures?

• What movements are still possible?

Hip trauma or surgery

Femoral fractures

• Lose supply to:

• Hip extensors/ stifle flexors

• Hock extensors/ digital flexors

• Hock flexors/ digital extensors

• Cutaneous sensation

• Still possible to:

• Abduct (Gluteals)

• Adduct (Obturator N)

• Protract limb / flex hip / extend stifle (Femoral N)

Describe the two branches of the tibial nerve in the equine.

• Tibial Nerve:

1/ Plantar nerves

• become plantar digital nerves

2/ Plantar metatarsal nerves

• Peroneal / Fibular nerve:

• 3/ Dorsal metatarsal nerves

• Medial and lateral branches

Describe the arterial supply found in the hindlimb.

• External iliac artery

• Leaves abdominal aorta & becomes

Femoral artery

• Runs through thigh region

• Popliteal artery

• Various branches

• Distal limb well supplied

• Foot injuries bleed!

Describe the venous drainage found in the hindlimb.

• deoxygenated blood back to heart

• Deep system:

• Follows arterial supply (Vein Artery Nerve often run together)

• Superficial system:

• Lateral saphenous vein

• Access to systemic circulation

• Drains into vena cava

• Medial saphenous vein

• More prominent in cats & horses

What is the femoral triangle?

• What are the anatomical boundaries?

• What is contained within this structure?

triangular shape in the medial aspect of the thigh

• Boundaries:

• Caudal - Pectineus (& Adductor)

• Cranial - Sartorius

• Contents:

• Femoral Vein Artery & Nerve

• Pulse - Femoral Artery

• Intravascular catheters - Femoral vein

• Femoral nerve = saphenous branch

What are the lymph nodes found in the hindlimb region, which of these are palpable?

• Hindlimb lymph nodes:

• Dog - Popliteal (caudal to stifle joint)

• Cow - Prefemoral (cranial to femur)

• Both palpable