Lower Leg Anatomy Flashcards
What compartments are leg muscles split into?
- Lateral
- Anterior
- Posterior
What nerves supplie the leg muscles?
Common fibular nerve:
- > Sup. Fibular nerve supplies lateral comp.
- > Deep Fibular nerve supplies Ant. Comp.
Sciatic Nerve -> Tibial Nerve -> Post. Comp.
What type of joint is the ankle and what bones articulate?
Synovial Hinge Malleolar mortise (malleoli & tibia form this bony arch) with trochlea of talus
When is the malleolar grip strongest in the ankle?
During Dorsiflexion
When is the ankle joint most unstable?
During Plantarflexion
Describe the ligaments making up the ankle joint capsule?
Thin on front and back
Strong on the sides thanks to Medial & LAteral Collateral Ligament
Describe the parts of the ankle medial collateral ligament? (Aka deltoid ligament)
3 slips arise from the medial malleolus (tibia) to:
- Talus
- Calcaneus
- Navicular
Together they form a large, triangular strong ligament
Function of the medial collateral ligament of the ankle?
Stabilises the joint during eversion
Describe the parts and clinical relevance of the lateral collateral ligament of the ankle?
3 slips:
- Anterior Talofibular
- Posterior Talofibular
- Calcaneofibular
Its weaker than the medial so its the most commonly injured
What muscles are responsible for Dorsiflexion of the ankle?
- Tibialis Anterior
- Extensor Digitorum Longus
- Extensor Hallucis Longus
- Peroneus
What muscles undertake plantar flexion of the ankle?
Gastrocnemius Soleus Plantaris Tibialis Post. Flexor Hallucis Longus Flexor Digitorum Longus
What movement causes ankle sprains?
Inversion
What is a pott Fracture?
Ankle dislocation
What is Footballer’s Ankle?
Repetitive strain injury to the ant capsule of the ankle
What is Tarsal Tunnel Syndrome
Tibial nerve compression deep to the flexor retinacula
What are the layers of the foot from plantar->in?
Layer 1 - Plantar Aponeurosis
Layer 2 - Lateral plantar nerve/artery
Layer 3 - Medial plantar nerve/artery
Layer 4 - Plantar then dorsal interossei
Major bones of the foot?
Talus - ankle joint Calcaneus/Os Calcis - Heel bone Tarsal bones Metatarsals Phalanges
AT what joints does the ankle move?
Subtalar or Talocalcaneal joint
Transverse tarsal joint
What muscles handle inversion/eversion?
Inversion - Tibialis post & Ant
Eversions - Fibularis Longus & brevis
Purpose of the arch of the foot?
Shock absorption by deforming on contact
Distribute weight over foot
Springboard during running/walking/jumping
Parts of the arch of the foot?
1 longitudinal arch made of 3 parts:
- Medial (most important)
- Lateral
- Transverse
How is the integrity of the foot arch maintained?
- Shape of united bones
- Plantar aponeurosis
- Long/short plantar ligaments
- Spring Ligament (Calcaneoclavicular)
- Intrinsic foot muscles
List some conditions related to foot arches?
- High arched foot can be congenital
- Acquired flat feet due to TIbialis post dysfunction
- Flat Feet is also common in old people and kids
What muscles form the Achilles Tendon?
Gastrocnemius & Soleus (plantar flexers)
How does ankle arthritis arise?
Mostly Post-traumatic
If theres no trauma history and they’re young (<50) it may be haemochromatosis
How do we treat ankle arthritis?
Ankle replacement
What is a cavovarus foot?
Cavo = high arch
Varus = medially slanted hindfoot
Calves may also be atrophic
What causes a cavovarus foot?
Congenital
Neuro disorders
Post-traumatic
Leads to muscles weakness:
- Intrinsic muscles - clawed toes
- Peroneus Brevis - Hindfoot varus
- Tibialis anterior - Equinus (can’t dorsiflex properly) and adducted forefoot.
How do we spot a varus?
Look from the front, if you can see the heel medially its called the “peekaboo” sign
How would a cavovarus foot present to us?
- Plantar calluses and shoe problems
- Ankle instability
- Altered Gait
- Stress fracture to lateral metatarsals
How do we test for a cavovarus foot?
Diagnosed clinically but coleman block test differentiates hindfoot varus or forefoot driven hindfoot varus
