1st ray Flashcards
1st ray axis and deviation. what is the primary action
45 deg transverse, 45 deg sagittal
deviation from dorsal-medial-proximal–>lateral-plantar-distal
dorsiflexion/plantarflexion
what is the total range of motion? ROM for dorsi/plantarflexion
total ROM: 10 mm, ROM dorsi/plantar: 5mm
when is the 1st ray considered hypermobile? what does this indicate
15-20mm, there is too much dorsiflexion, therefore limits ROM for MPJ–>leads to hallux limitus
when is 1st ray plantarflexed? what is needed for plantarflexion?
midstance and propulsion for proper 1st MPJ function by allowing dorsiflexion of proximal phalanx in toe off.
stable midtarsal joint, supinated subtalar joint
what is responsible for the stabilization of the lesser tarsus and 1st metatarsal against ground allowing for plantarflexion? allow supination to be more effective
peroneus longus
what is responsible for the actual plantarflexion
abductor hallucis
what are the axis and motion of 1st MPJ
vertical axis: passive transverse motion
transverse axis: 4 centers of motion (moves with motion of 1st MPJ)
1st MPJ ROM
60-65 deg dorsiflexion
5-10 deg plantarflexion
what are the gait requirements of 1st MPJ
stability and plantarflexion of 1st ray
normal sesamoid function–>acts as pulley for muscles acting on hallux for stabilization during propulsion
normal function of 1st MPJ muscle stabilization
describe the 1st MPJ motion from midstance to toe offf
1st MPJ acts as hinge for 1st 20 deg of motion
arthroidal motion:
sliding motion with plantarflexion of 1st ray with heel lift, STJ supination, and normal sesamoid function
dorsiflexion to end ROM during propulsion with 35 deg knee flexion and 20 deg ankle plantarflexion
what is the motion/function of lesser rays?
pure dorsiflexion/plantarflexion
what is the axis/motion/function for 5th ray?
axis:
20 deg transverse
35 deg sagittal
Proxmal/plantar lateral–>distal/dorsal/medial
mainly dorsi/plantarflexion wiht some abd/add and eversion and inversion
function: plantarflexion required for5th MPJ dorsiflexion during propulsion
Lesser MPJ axis
vertical: passive ROM
transverse: dorsiflexion and plantarflexion
what are the muscle stabilizers to the toes?
what causes the lesser MPJ to dorsiflex?
flexor digitorum brevis and longus, interossei and lumbricals
dorsiflexion: extensor digitorum longus through extensor sling
what is required from lesser mPJ for gait?
dorsiflexion required during propulsion
