Musculoskeletal System: Complex Movemnts ( Standing And Gait ) - Lecture 11 Flashcards
What is quadrupedal standing
On 4
Gives lots of stability
Limbs are active at many joints and demands energy
What is bipedal standing
-Relatively small area of contact with ground
-planter surface of feet
-energy efficient
- special atomically features at joints to assist balance
- standing is achieved with very like muscular support - mostly at ankle joint
What is line of gravity
Gravity forms this line through our body and gravity is trying to make us fall over, but the arrangement of our joints allow us to stand up right for long periods of time and be energy efficient.
And how we maintain this upright stance is that we need atomical solutions
- posterior to the hip
- anterior to the knee
- anterior to the ankle
In bipedal standing ( hip ) where is the line of gravity
Line of gravity is posterior to the joint and pushes joint to extension and the ligaments surrounding the hip joints become tight in response to the posterior force excreted by the line of gravity and it locks the hip joint in a stable, extended position and this means that no energy is spent
Capsular ligaments of the hip
Hip in flexion:
When the hip is in flextion the capsular ligament are loose anteriorly ( in front of the joint ) and then become tight posteriorly ( benhind the joint ) during hip flexion. This loose anteriorly and tight posteriorly allows for thr range of motion required during hip flexion while still maintaining stability and support around the joint
Hip in Extension
- the capsular ligaments become tight anteriorly ( in front of the joint ) and loose posteriorly ( behind the joint )
Bipedal standing - knee ( line of gravity )
Line of gravity for the knee is anterior to the joint and then pushes joint to extension and then ligaments are tight so this means that the joint is locked and no energy is spent
Bipedal standing - ankle ( line of gravity )
The line of gravity for the ankle is anterior and then it pushes it into dosiflexsion and so the joint is NOT locked and the planterslexors needed to stabilise and energy is consumed
What is the giat cycle
Complex series of movements made up of stance phase and swing phase and transition phases between the heel strike and toe off and involves a lot of movement and muscles
What is stance phase and swing phase
Limb comes off the ground and swings through the air to come in front and then foot hits the ground and weight is transferred to the foot and when the foot is on the ground this is called stance phase and double stance phase is when both feet are touching the ground
Swing phase has one job, to bring the limb in front of the body and make sure we don’t fall down
What happens at early stance + heel strike
Hip
- in front of the body, so in flexion but moving into extension
- agonist = gluteus maximus and hamstring, so this is the muscles that cause extension at hips
Knee
- in extension ( locked for stability ) making the best use for minisci ( shock absorbers )
- stabilisers : quadriceps femoris, hamstrings and gastrocnemius
Ankle
- in dorsiflexion ( stable - best bony congruence ), but moving into plantarflexion, preparing for the push off phase
- Agonist = triceps surae
- antagonist = tibialis anterior needed to control rate of foot drop to ground, ensuring a smooth transisition from dorsiflexion to planter flexion
Mid stance
Hip
- continuing movement into extension, with the aim of maintaining stability and supporting body weight
- agonist = gluteus maximus and hamstrings, these he,p extend the hips further
Knee
- moving from extension to sight flexion
- agonist = hamstring and gastrocnemius, helping to absorb shock and maintain balance as we start to move forward.
Ankle
- continue to move to planter flexion
- agonist = triceps surae
Late stance ( includes toe off )
Hip
- in extension
- gluteus maximus and hamstrings
Knee
- in extension due to position of body
- hamstrings and gastrocnemius contracting ready for next movement
Ankle
- in full planterflexion
- triceps surae ( strong for propulsion )
Early swing
Hip
- in extension, moving to flexsion as the leg swings forward
- agonist = iliopsoas and rectus femoris. These muscles contract to lift the thigh and swing through leg forward during early swing
- antagonist = gluteus maximus and hamstrings control rate of swing and prevent excessive movement
Knee
- in flexsion, to lift the foot from the ground
- agonist = hamstring and gastrocnemius, these muscles contract and to bend the knee and lift the foot off the ground during early swing
Ankle
- in dorsiflexion to allow Clearance of toes during swing
- agonist = tibialis anterior. This muscle will contract and lift the foot and toes upward, ensuring clearance
Mid swing
Hip
- in flexion, allowing the thigh to continue swinging forward
- agonist = iliopsoas and rectus femoris. These muscles contract to maintain flexsion of the hip during mid swing
- antagonist = gluteus maximus and hamstrings control rate of swing by resisting excessive movement
Knee
- in flexsion to continue lift foot from ground
- agonist = hamstring and gastrocnemius. These muscles contact to maintain flexsion of the knee
Ankle
- in dorsiflexion to allow clearance of toes during swing
- agonist = tibialis anterior. This muscle contracts to lift the foot and toes upward.
Late swing
Hip
- in flextion, preparing for the upcoming heel strike
-agonist = iliopsoas and rectus femoris. These muscles continue to contract to maintain hip flexsion during late swing
Knee
- moving from flexsion into extension to prepare for heel strike
- agonist = quadriceps femoris. This muscle contracts to extend the knee and prepare the leg for weight bearing during late swing
Ankle
- in dorsiflexion for most stable joint position for heel strike
- agonist = tibialis anterior to pull the foot upward into dorsiflexion
- stabiliser = triceps surae to keep ankle stable, ensuring proper foot positioning for heel strike
