Monday, 26 October 2015

Fibularis Brevis - a lower leg muscle

Fibularis Brevis is the sister muscle to Fibularis Longus and lives in the lateral compartment of the lower leg.  Lateral meaning 'furthest away from the midline (center) of the body 
- opposite of  'Medial'.

Fibularis: referring to the fibula (lower lateral leg bone)

Longus: if a muscle name includes the word longus - there is a good chance that there is a shorter version of this muscle.

Now would be a good time to mention that the fibularis muscles are also known as The Perroneal muscles - Perroneus Longs & Brevis - more of an old-school term ;) I prefer fibualris because these muscle run along side the fibula bone.

Fibularis Brevis Muscle Attachment Points

Origin:  Distal 1/2 of the lateral fibula
(distal meaning the half of the fibula bone that is furthest away)

Insertion:  Lateral surface of the base of the 5th metatarsal
(the 5th metatarsal is one of five long bones in your foot - it eventually turns into your pinky toe!)

The distal tendon of both brevis and longus  extend down to the outside ankle (aka lateral) just behind the lateral malleolus.

Fibularis Brevis Muscle Actions

a) plantarflexion of the foot at the ankle joint
b) eversion of the foot at the ankle joint 

a) Plantar-flexion aka "pump the breaks" - another way to plantar-flex would be 'heel lifts' (going from standing to balancing on your toes/balls of your feet)

b)  Eversion - big toe down! pinky toe up ! 

This is a great exercise - the fibularis muscles are weak on most people and need to be strengthened! 

Until next time! Where we'll be continuing down into the foot..