first metatarsophalangeal joint

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first metatarsophalangeal joint

; 1 MTPJ synovial joint at the articulation of the base of proximal phalanx, head of first metatarsal, plantar aspect of head of first metatarsal and hallucal sesamoids (embedded within tendon of flexor hallucis brevis muscle); ginglymoarthrodial joint allowing both sagittal-plane hinge movement (dorsiflexion/plantarflexion) of hallux toward the dorsum of first metatarsal head, and gliding sagittal-plane movement as first metatarsal head moves through an arc in a plantarwards direction; combined ginglymoarthrodial 1 MTPJ movement ensures that, immediately before toe off, the pulp of the hallux is in ground contact and the first metatarsal is at almost 90° to the horizontal plane (see Table 1)
Table 1: Features of the neutral or reference position of the joints of the foot and lower limb
JointCharacteristics at neutralAvailable motion
HipThe legs are in line with the trunk, parallel to one another and in the sagittal plane
The femoral condyles lie in the frontal plane
Flexion/extension
Adduction/abduction
Internal/external rotation
KneeKnee joint fully extended
Thigh and lower leg in line in sagittal and frontal planes
Flexion
AnklePlantar aspect of the foot on the horizontal plane/weight-bearing surface
Lower leg perpendicular to the sagittal and frontal planes/weight-bearing surface
Dorsiflexion/plantarflexion
SubtalarBisection of the posterior aspect of the calcaneum perpendicular to horizontal plane/weight-bearing surfaceSupination/pronation
Midtarsal complexPlantar aspects of the metatarsal heads lie in horizontal plane/on weight-bearing surface
Joint maximally pronated
Supination
First rayPlantar aspect of the first metatarsal head in same plane as lesser metatarsal heads, and horizontal planeDorsiflexion/plantarflexion
Inversion/eversion
Second/third/ fourth raysMaximally dorsiflexed on horizontal plane/weight-bearing surfacePlantarflexion
Fifth rayPlantar aspect of the fifth metatarsal head in same plane as lesser metatarsal heads, and horizontal planeDorsiflexion/plantarflexion
Inversion/eversion
First metatarsophalangeal jointPlantar aspect of hallux in ground contact on horizontal plane and the hallux neither adducted nor abductedFlexion/extension
Adduction/abduction
Circumduction