FOOT ARTHROLOGY Flashcards
Subtalar joint
Hind foot
Classification: synovial simple plane multi axial
Articulations:
▪️Talus: concave inferior/ posterior
▪️Calcaneus: convex superior/anterior -covered in articulations hyaline cartilage
Fibrous capsule of subtalar
Loose fibrous capsule attaches to all joint margins
Thickened medially laterally and posteriorly - talocalcaneal ligaments
Thinnest anteriorly attaches to sinus tarsi
Forms interosseous ligament at talocalcaneonavicular
Ligaments (caspular thickenings)
Subtalar
a. Lateral talocalcanean ligament:
Lateral process of talus—- lateral calcaneus
b. Medial talocalcenean ligament:
Medial tubercle (posterior process) of talus——
Sustentaculum tali
c:Posterior talocalcanean ligament:
Lateral tubercle (posterior process) of talus—
Posterior calcaneus
Accessory ligaments of subtalar joint
d. Interosseous talocalcaneal ligament
- Most important ligamentous structure unites talus and calcaneous prevents separation
- Strong – dense fibrous tissue
- Anterior and posterior parts are both quadrilateral and attach from the floor of the sinus tarsi
Anterior fibers – run superior and anteriorly attach behind articular surface of head of talus
Posterior fibres – superiorly and posteriorly attach in front of concave articular surface of underside of talus
•Direction of fibres: axis in between ant and post fibres means movement of upper body will result in fibres being under tension = SUPPORT
e. Ligamentum cervicis
Strong cord like structure at lateral end of sinus tarsi limits inversion of hind foot
*calcaneofibular talofibular ligament(LCL) and tibionavicular ligament( deltoid ligament) act as accessory ligaments for subtalar joint
Midtarsal joint
Lateral:
•Calcaneocuboid joint
Synovial, simple, plane, multi-axial
Medial:
•Talocalcaneonavicular joint
Synovial, compound, ball and socket, multi axial
Midtarsal joint - Talocalcaneonavicular joint
Ball and socket – formed both of bone and fibrous tissue
Ball: head of talus
Socket:
• anteriorly: formed by concave posterior surface of navicular
Posteriorly: formed by concave facet on the sustenraculum tali And the anterior upper surface of the calcaneous
Inferiorly: Medially formed by plantar calcaneonavicular ligament (spring)
Latterly by bifurcate ligament
Midtarsal joint - Talocalcaneonavicular
Capsule and synovial membrane
True fibrous capsule present on posterior and dorsal aspect
Anteriorly: navicular, anterior tibiotalar, plantar calcaneal, bifurcate
Posteriorly blends with subtalar at sinus tarsi forming interosseous ligament
Synovial embrane lines all non-articular surfaces – fat pad assists in fluid distribution
Planter calcaneonavicular ligament (spring ligament)
Thick dense fibroelastic ligament
Anterior and medial sustentaculum tali to entire width of inferior navicular and tubercle
smooth superior surface contains a fibrocartilaginous plate for articulation with head of talus reduces friction
Resists inferior displacement of talus
Dorsal talonavicular ligament
Attaches from the neck of talus to the dorsal surface of navicular
Tense in inversion
Bifurcate ligament calcaneonavicular
Complete socket laterally
Attaches from upper anterior calcaneous to adjacent lateral navicular
Midtarsal joint - Calcaneocuboid joint
Reciprocally shaped shared undulations roughly quadrilateral joint
. surface of anterior facet on calcaneal
. posterior facet on cuboid
Midtarsal joint - Calcaneocuboid joint
Fibrous capsule and synovial membrane
Simple complete fibrous capsule surrounds the joint lined by synovial membrane
Thickened dorsally forming the dorsal calcaneocuboid ligament
Calcaneocuboid Ligaments- dorsal
Dorsal calcaneocuboid ligament:
Passes between dorsal surfaces of calcaneous and cuboid
Thin yet broad caspular thickenings
Bifurcate ligament:
Arises from same origin as calcaneonavicular part upper anterior calcaneus
Attaches to the dorsomedial angle of cuboid
Calcaneocuboid Ligaments- plantar
- Long planter ligament:
Superficial to short planter ligament
Posteriorly attaches between the medial and lateral processes of the canlcaneal tuberosity
Supports the lateral planter aspect of foot
Direction of fibres–
Deep fibre is attach to the ridge of the cuboid
Intermediate fibres attach beyond the groove of the cuboid – form of fibrous arch over the peroneus longus
Superficial fibre is attached to base of lateral 4 metatarsals
2.Short planter calcaneocuboid ligament:
Blends with joint capsule inferiorly
Strong and short
Arises from a rounded eminence on the inferior calcaneus to attach to the inferior cuboid posterior to the groove of the peroneus longus
Movements of the subtalar and midtarsal joints
Complex combined movements of three joints
Movement of the foot in a modified frontal plane as ankle itself is a uniaxial joint movement only occurs in the sagittal plane
Enables:
•Maximal for contact with the floor over uneven surfaces
•Changes in direction particularly moving at speed
Inversion
Inversion: Sole of foot turned inwards towards midline of body
Supination and adduction of foot
Combination of movement of other movements of the foot
Arthrokinamatics:
Navicular moves medially which is adduction and superiorly which is supination while the cuboid moves downwards
Tension in dorsal talonavicular ligament, bifurcate ligament and ligamentum cervicis
Eversion
Enversion : Sole of foot turned outwards away from the midline of the body
Pronation and abduction of foot
Combination of movement of other movements of the foot
Has a smaller range of movement due to the extent of joint surfaces in this direction
Arthrokinamatics:
Cuboid moves laterally which is abduction and superiorly which is permission for the navicula moves downwards
Tension in bifurcate ligament, short plantar calcaneocuboid ligament
Arches of the foot
Functions
Functions:
Distribute body weight to the weight-bearing areas he’ll heads off first and fifth metatarsals
Absorbs force and shock
Stores force for use in propulsion(windglass effect) during locomotion
Phone concavity provide safe passage for neuro vascular structures nerves veins and arteries throughout the foot
Arches of the foot
1) Medial longitudinal arch:
TALUS IS KEY STONE
1st Metatarsal ,medial cuneiform ,navicular, talus, calcaneus
2) Latetal longitude Arch:
CALCANEUS IS KEY STONE
5th metatarsal, cuboid, calcaneus
Shallower and Lower to floor more ridgid
3) Transverse arch
2nd MT IS KEYSTONE
Heads of metatarsal 1-5 (2nd MT)
Navicular, cuboid, cuneiform
Spring ligament
Medial longitudinal arch
Because the talus is receiving weight from the body and because of its wedge shape at this point It wants to push between the navicular and calcaneous that’s where the spring ligament is so important at resisting that maintains height of arch
Tarsometatarsal and intermetatarsal
The tarsometatarsal and intermetatarsal joints are synovial/plane joints supported by dorsal, plantar and interosseous ligaments. These joints are flexible and allow the foot to adapt to uneven surfaces.
Metatarsophalangeal and interphalangeal joints
The metatarsophalangeal joints are synovial/condyloid joints, while the interphalangeal joints are synovial/ hinge joints. They are both supported by medial and lateral collateral ligaments, and plantar ligaments.
Supporting ligaments of the subtalar joint
a. Medial talocalcanean ligament;
b. Posterior talocalcanean ligament;
c. Lateral talocalcanean ligament;
d. Interosseous talocalcanean ligament; and
e. Ligamentum cervicis.
Midtarsal joint- talocalcaneonavicular joint ligaments
a. dorsal talonavicular ligament;
b. plantar calcaneonavicular (‘spring’) ligament
c. bifurcate calcaneonavicular ligament
(2 parts = calcaneonavicular + calcaneocuboid)
Midtarsal joint- calcaneocuboid joint ligaments
a. dorsal calcaneocuboid ligament;
b. plantar calcaneocuboid ligament (short plantar);
c. plantar calcaneocuboid ligament (long plantar)
d. bifurcate ligament (calcaneocuboid part)
