Lecture 20 Flashcards
What are the features of the femur?
Head Greater trochanter Inter trochanter line Neck Fovea (pit) for ligament of head Lesser trochanter Anterior surface of body Supracondylar lines – lateral and medial Lateral epicondyle Lateral condyle Adductor tubercle Medial epicondyle Medial condyle Patella surface Trochanteric fossa Intertrochanteric crest Gluteal tuberosity Spiral line Pectineal line Medial lip of linea aspera Lateral lip of linea aspera Nutrient foramen Popliteal surface Intercondylar line Intercondylar fossa
What are the features of the tibia?
Medial conylde Lateral condyle Apex of head Tubercles of intercondylar eminence Medial tibial plateau Lateral tibial plateau Tibial tuberosity Shaft – sharp, cutaneous Body Medial malleolus Soleal line Nutrient foramen Medial border Groove for tibialis posterior tendon
What are the features of the fibula?
Head Body Lateral malleolus Apex of head Posterior border Interosseous membrane
What are the features of the patella?
Base
Sesamoid apex at distal end
Medial facet
Lateral facet
Articular surface
Rough on anterior side for quadriceps to form a tendon
Facets make contact with condyles of tibia
What type of fracture is most common in the lower leg?Where does it occur and why does it occur here?
Tibial occurs most often.
Most tibial fractures occur at the junction of the middle and inferior thirds.
Boot top fracture in skiers.
Bone is narrowest and poor blood supply in this region.
Osgood Schiatter syndrome – tibial tuberosity/epiphysis can develop inflammation and infection, the entire epiphysis can slide off the tibia and tibial condyles.
Fractures often comminuted – produces lots of little fragments of bone.
Pott’s fracture – a fracture of the lower end of the fibula, usually associated with a dislocation of the ankle.
Fracture of the tibia is associated with fibula fracture – common fibular nerve endangered proximally.
What are the three fascial compartments and what types of muscles do they contain?
Anterior
Dorsiflexors
Inverters
Lateral
Evertors
Posterior Planterflexors Invertors Superficial Deep
What is crual fascia?
Thick Continuous with: Fascia lata superiorly Periosteum of tiba anteiorly Intermuscular septa (deep) Ankle retinaculae inferiorly
What are the types of ankle retinaculae?
1 flexor 2 extensors 2 fibular Bind tendons Create tarsal tunnels (anterior and posterior)
What is compartment syndrome? Which compartment of the leg is most commonly compressed? What structures are compressed? What are the symptoms? How can it be resolved?
Muscles surrounded by tight fascia are unable to expand on exertion.
If swelling in neurovascular bindle occurs structures are susceptible to compression – compartment syndrome.
Anterior compartment of leg is most commonly compressed.
Lymphatics, veins, arteries, nerves (and vessels to nerves – ischaemia of nerve).
Symptoms: pain (on exertion), pain, pulse less, paraesthesia (lack of sensation).
Fasciotomy to release fluid and decompress.
What are the 4 anterior lower leg muscles and what nerve are they innervated by?
Tibialis anterior:
Dorsiflexion (of ankle).
Inversion.
Proximal aspect of the tibia to the base of the first metacarpal/arch of foot.
Extensor hallucis longus:
Deep to tibialis anterior.
Inserts on extensor expansion of big toe.
Extensor digitorum longus:
Lateral to tibialis anterior.
Inserts onto extension expansion of 4 lateral toes.
Fibularis tertius: Dorsiflexion. Eversion. Lateral compartment. Goes under extensor retinaculum to insert onto superior aspect of 5th metatarsals.
Deep fibula nerve
What are the 2 lateral lower leg muscles and what nerve are they innervated by?
Fibularis longus:
Inserts onto 1st metatarsal and medial cuneiform .
Important role in maintaining transverse arch of foot.
Fibularis brevis:
Inferior.
Inserts onto inferior aspect of the base of 5th metatarsal.
Superficial fibula nerve.
Where is the common fibula nerve and what is it’s clinical significance?
Common fibular nerve passes behind head and neck of fibula.
Divides into superficial and deep.
Superficial fibular nerve supplies muscles then becomes cutaneous and innervates skin of distal leg and dorsum of the foot.
Deep fibular nerve pierces anterior intermuscular septum to anterior compartment.
Common fibular nerve compression against head of fibular
Dorsiflexion and eversion is compromised causing foot drop and steppage gait.
Unopposed plantarflexion and unopposed inversion occurs.
Where is the popliteal fossa and what does it contain?
Between hamstring tendons (superiorly) and gastrocnemius (inferiorly).
Contains:
Sural nerve
Lesser saphenous vein
Tibial and common peroneal nerves
Popliteal artery and vein – branches and tributaries
Popliteal lymph nodes
What are the superficial posterior lower leg muscles?
What nerve are they innervated by?
Gastrocnemius Power Two heads (lateral and medial) Condyles of femur to achilles tendon – calcaneal tuberosity Plantarflexion Plantaris Deeper Might not always be present Soleus Postural Antigravity muscle Originates tibia/fibula/interosseous membrane Inserts onto calcaneal tuberosity
Tibial nerve
What are the deep posterior lower leg muscles?
What nerve are they innervated by?
Popliteus Small, deep Begins intracapsular Inserts onto proximal part of tibia Unlocks the knee – from a weight bearing to non weight bearing position. Deep to retinaculum through tarsal tunnel Tibialis posterior deepest Flexor digitorum longus Flexor hallucis longus Through tarsal tunner to big toe
Tibial nerve
