17 Flashcards
What muscles are in the anterior compartment
- tibialis anterior
- extensor hallucis longus
- extensor digitorum longus
What muscles are in the lateral compartment of the leg
- fibularis longus
- fibularis bevis
Femoral artery passes under which ligament?
Ingunal
Main blood supply to all compartments of the thigh is..?
- deep femoral artery
What does the popliteal artery split into?
Anterior and posterior tibial arteries
Fibular artery is a branch of the _____ artery
Posterior tibial
Sciatic nerve devices into:
- common fibular nerve
- tibial nerve
Where does the division of the sciatic nerve into tibial and common fibular nerve occur?
Usually in the lower third of the posterior thigh
What muscles do the tibial nerve supply ?
Posterior thigh
- biceps femoris long head
- biceps femoris short head
- semim?endinosis
What does the tibial nerve innervate ?
- posterior compartment of the thigh
- posterior compartment of the leg
What would be the consequence of injury to the tibial nerve
- can’t flex knee
- can’t Plantarflexion
- can’t extend hip
- inversion damaged
What does the common fibular nerve innervate?
Short head of biceps femoris
What two branches does the common fibular nerve divide into?
- superficial and deep branches near the head of the fibula
Where does the deep fibular nerve descend in and along with what?
- depends in leg along with the anterior tibial artery and vain
Functions of the deep fibular nerve
- dorsiflexion (all)
- toe extension (EHL, EDL)
- inversion (tibialis anterior)
What does the superficial fibular nerve innervate ?
Lateral compartment of the leg
Function of the superficial fibular nerve
- eversion
- Plantarflexion
What is the most common nerve in the lower limb to be damaged?
Common fibular nerve
Why is the common fibular nerve so prone to damage?
It is relatively unprotected at the fibular neck
- very superficial 33
What things may cause a common fibular nerve injury ?
Trauma: fracture of fibular head
Compression, e.g. plaster cast
What would be the consequence of injury to the common fibular nerve ?
Supplies anterior and lateral compartments
- lose dorsiflexion
- weakened inversion
- lose evision
Swing phase versus stance
Swing - a foot is off the ground
Stance - both on the ground
Note that the stance phase of one limb does not end immediately when the opposite limb strikes the ground (i.e., there is a time when both limbs are on the ground) - period of double support
How does running differ to gait
- no period of double support during running
- time and frequency of stance phase is reduced
- times when both feet are off the ground (float/aerial phase)
What main muscle groups maintain standing ?
Primarily extensor muscles of the back and plantarflecors
- resctus spinae
- solues
When standing what is happening at the lower limb joints?
- hip and knee joint are extended
- hip joint ligaments are all taut (doesn’t have to use much muscle energy to maintain upright)
The centre of gravity is anterior to the ankle joint, so people tend to fall forward, but plantarflexors counteract this “fall”
What is the repetitious sequence involved in the gait cycle?
- propulsion
- support
From standing position, what is the gait cycle initiated by?
- relaxation of plantarflexors
- dorsiflexion of the ankle joint
- then the limb enters the swing phase
4 main phases of the gait cycle
- Heel-strike (stance)
- Support (stance)
- Toe off (stance)
- Carry through (swing)
stance phase, what does it begin with, what does it end with ?
Stance begins with heel strike, ends with toe off
What must the limb do in the stance phase of the gait cycle?
Limb needs to accept weight, decelerate mass, stabilise pelvis, preserve foot arches
Factor to consider at each phase of the gait cycle
- position of each lower limb joint
- muscles that position the joint
Whats happening in the hip at the keel strike?
- hip joint is flexed
- rectus femoris
- illospoas
What is happening at the knee during heel strike?
- knee joint is extended
- quadriceps
What is happening at the ankle joint in heel strike ?
Ankle is dorsi-flexed
- tibialis anterior
- EDL + EHL
D
B
A
D
Features of hip joint during initial contact
- shock absorption
- flexed hip is extended after heel strike
- hip extensors are active - concentric contraction (hamstrings, glutemax)
Hip flexed
Concentric vs essentric vs isometric
- concentric - muscle is shortening to produce a contraction
- essentric - muscle is elongating
- isometric - muscle isn’t changing
Features of the hip joint during mid stance
- progress body over stationary foot
- maintain limb and trunk stability
- hip extension
- hip abductors (to keep pelvis level)
Hip in anatomical position
Features of the hip joint during late stance
- progress body beyond supporting foot
- accelerate body
- hips start to flex is preparation for swing
Change from hip extension to flexion
Features of the hip joint during mid swing
- limb advancement
- foot clearance off the ground
- hip flexors are doing concentric contraction
Hip in approximate anatomical position
Features of the hip joint during late swing
- complete limb advancement
- prepare for stance phase (deceleration)
- hip extensors contract to decelerate the forward movement - concentric contraction
Hip is flexed
Features of the ankle joint during heel strike
- initial impact, deceleration
- shock absorption
- dorsiflexors contract to lower foot to ground (ACTING ESSENTRICALLY)
Ankle is dorsiflexed
Features of the ankle joint during the mid stance
- foot has been lowered to the ground
- movement forward
- dorsiflexors contract to pull tibia forwards over the foot, then gravity and momentum take over
Ankle in anatomical position
Features of the ankle joint during late stance
- prepare for swing phase
- accelerate body forward
- plantarflexors are undergoing concentric contraction
- toe-off propulsion - FHL is a key muscle that propels the body forwards
Ankle plantarflexed
Fearture of the ankle joint during mid swing
- limb advancement
- foot clearance off the ground
- dorsiflexors: concentric contraction
- toe extensors: concentric contraction
Ankle dorsiflexed
Toes extended
Features of the ankle joint during late swing
- complete limb advancement
- prepare for stance phase (deceleration)
- dorsiflexors and toes extensors ensure foot is in optimal position for heel strike
- at heel strike, dorsiflexors immediately contract eccentrically, to control lowering of the foot to the ground
Ankle dorsiflexed
What do high heeled shoes do?
- Increased pressure on metatarsophalangeal joints during stance
- Prone to hallux valgus (bunion), calluses, metatarsalgia
- increased Plantarflexion which leads to increased knee flexion and increases lumbar lordosis
- increased muscle activity.. may lead to fatigue earlier
How does gait change with age?
- muscles get weaker / atrophy
- flexed posture in lower limb during standing, flexed neck
- balance compromised
- gait is slower, decreased stride length, increased stance time, more time in double stance, less propulsive forces developed
Other causes of change in gait
- hip pain (osteoarthritis, osteoporosis)
- medical treatment such as androgen therapy in men
- post-total hip joint replacement
- reduced muscle force
- step width increases
- forward acceleration decrease sets
——^- at risk of falling and bone fracture
What changes in gait can cause a risk of falling and bone fracture
- reduced muscle force
- step width increases
- forward acceleration decreases
Fat infiltrate
Fat infiltrate
Fat infiltrate
Hip abductors - gait changes
- gluteus, medius, minimus . Tensia fachalada
- unable to maintain pelvis level during single leg stance (contralateral drop)
Compensation: leans to the opposite side
