Download FOOT AND ANKLE—LECTURE 1 ANATOMY Includes Bones, joints, muscles

FOOT AND ANKLE—LECTURE 1
ANATOMY
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Includes
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Bones, joints, muscles, ligaments, nerves
Is important for diagnosis and treatment
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For example, it’s good to look at all lower extremity problems when you look at ankle pain
Important landmarks to know:
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Tibia, tibial tuberosity, fibula, fibular head, interosseus membrane, medial and lateral malleoli,
anterior tibial-fibular ligament, talo-fibular ligaments (anterior and posterior), deltoid ligament
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Tibial tuberosity—patellar tendon pulls on this as you grow older and it hypertrophies.
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An ankle sprain can be transmitted up to the fibula and to the fibular head—
Maisonneuve fracture
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Anterior tibiofibular and anterior talofibular ligaments are the most commonly sprained
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Base of the fifth metatarsal can have a dancer’s fracture associated with it—it is always
good to check on these
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Remember bones of the foot.
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The talus is the keystone of the foot
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It only has one blood supply
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Is the “scaphoid” of the foot
FUNCTIONAL ARCHES
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Arches are formed by dense connective tissue suspended between the bony surfaces of the foot
to maintain foot structure upon weight-bearing and aid in shock absorption
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Lateral longitudinal arch (weight bearing arch)
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Is made up of calcaneus, cuboid, and 4th and 5th metatarsals
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Common dysfunction is INFERIOR CUBOID somatic dysfunction (SD) which is most
frequently secondary to a talocalcaneal dysfunction in which the talus is anterior and the
calcaneus is IR
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Is supported by the long plantar ligament
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Medial longitudinal arch (or spring arch)
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Is made up of talus, navicular, cuneiforms, 1st-3rd metatarsals
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This is the major shock absorbing arch;
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Most common dysfunction is anteromedial lesion of talus on the calcaneus which moves
the navicular inferiorly
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This is a frequent cause of foot pain
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Is supported by the plantar fascia and tibialis posterior muscle
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Can be a source of plantar fasciitis—if you stretch this fascia, it helps
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Can also form bone spurs on the calcaneus where this fascia inserts
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Is contiguous with the gastroc and soleus fascia
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Transverse arch
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Is a rigid arch which maintains the osseous architecture of the foot while the more
flexible longitudinal and metatarsal arches provide the function of the foot
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There are OMM techniques that we discussed in lab for dysfunctions in this arch
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MUSCULAR ATTACHMENTS FOR TRANSVERSE ARCH
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These muscles support the arch:
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Peroneus/fibularis longus m. induces the eversion/pronation of the
CUBOID
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Cuboid rotates laterally
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Moves laterally around an anterior-posterior axis
(eversion)
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The edge of the cuboid is prominent on the midline of the
plantar surface
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Tibialis anterior m. induces the inversion/supination of the
NAVICULAR
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Navicular rotates medially
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Moves medially around an anterior-posterior axis
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The edge is prominent on the midline of the plantar surface
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This arch can be flattened, and you can palpate tenderness as the bones slip
down in SD—cuneiforms most common (especially the second
cuneiform)
Metatarsal arch
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Is free of muscle attachments so the foot can adjust to uneven ground
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The arch flattens with weight bearing
GAIT AND ARCHES
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As you walk, you start off on the lateral arch, then move to the medial arch before toeing off
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If you lost your big toe, you may have issues with balance
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KNOW what these arches are made up of
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Problems with arches include pes planus and pes cavus
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Pes planus—flat feet
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Feet are everted as you stand on them
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Somatic dysfunction in flat feet can radiate up the leg into the SI joint
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You can also have a hypertrophied deltoid ligament in pes planus
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Muscle control of the foot aids in proprioception and balance
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Muscular retraining and strengthening of the foot muscle should be the first step in gait training
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Increased tone and therefore improved arch function also takes “shock” strain off of other joints
(knees, hips, low back, etc.)
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When you walk the weight shifts from heel to the lateral border of the foot, then to metatarsal
heads and finally to the hallux to push off
KEY MUSCLES OF THE FOOT
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Fibularis longus
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Acts to plantarflex the foot at the talocrural joint
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Acts to evert/pronate the foot at the subtalar joint
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Supports the transverse arch of the foot
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Originates on the head of the fibula/interosseus membrane
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Inserts on the medial cuneiform and the base of the first metatarsal
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Tibialis anterior
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Acts to dorsiflex the ankle at the talocrural joint
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These two actions allow the cuneiforms to depress
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The motions are named for a midline point on the plantar
surface of the bone
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When these bones glide down, the foot flattens
Acts to invert/supinate the foot at the subtalar joint
Originates on the tibia and the interosseous membrane
Inserts on the medial and plantar surface of the medial cuneiform, and the medial base
of the first metatarsal
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Tibialis posterior
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Originates on the fibula and tibia
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Inserts on the navicular tuberosity and the medial, intermediate, and lateral cuneiforms
and the bases fo the 2nd-4th metatarsals
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Action is to plantarflex the foot at the talocrural joint
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Also inverts/supinates the foot at the subtalar joint
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Supports the longitudinal and transverse arches of the foot
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Fibularis/peroneus longus
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Is the antagonist to tibialis posterior
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Extensor hallucis longus
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Have patient extend their big toe to test for the L5 reflex, as there is no DTR for L5
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Remember our muscles on the bottom of the foot that we must palpate through
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Gastrosoleus complex
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You can get Achilles tendonitis
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Bad if you rupture the Achilles tendon
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Can be tested using Thompson’s—squeeze the gastroc and the foot should
plantarflex
ANKLE JOINTS
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Tibiotalar joint and pes—“ankle” and “foot”
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Components include
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Tibia, fibula, talus, calcaneus, navicular, cuboid, cuneiforms (3), metatarsals
(5), phalanges (14)
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AXIS OF MOTION:
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MAJOR AND MINOR MOTIONS:
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Dorsiflexion with posterior glide
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Plantarflexion with anterior glide
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TIBIOTALAR JOINT IS THE TRUE ANKLE JOINT/ANKLE MORTISE
TALOCALCANEAL JOINT/SUBTALAR JOINT
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Act as shock absorbers for the foot—distributes forces
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AXIS OF MOTION:
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Motions:
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Posteriolateral glide with foot inversion
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Anteromedial glide with foot eversion
Pronation and supination occurs here around an oblique axis
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Each of these are COMBINATIONS of TRIPLANAR MOVEMENTS
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SUPINATION—PIA (pia mater)
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Plantarflexion
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Overall motion:
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The joints plantarflex, invert, and supinate at the same time
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This is the most common way to dislocate your ankle
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The more mobile a joint is, the more prone to dislocation it is, and the ankle is
more mobile in inversion
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Another example: shoulder dislocations
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The foot tends to stay inverted all the time in chronic ankle sprains
LIGAMENTS OF THE FOOT
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Medially, we have:
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the deltoid ligament
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Is made up of anterior tibiotalar, tibionavicular, tibiocalcaneal, and posterior
tibiotalar ligaments
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Is very strong
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The plantar calcaneonavicular (spring) ligament helps maintain the medial arch
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Laterally we have:
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Anterior talofibular ligament
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Calcaneofibular ligament
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Is the second most commonly sprained
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Posterior talofibular ligament
ANKLE AND FOOT ROM—physiologic motions of the ankle
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Be mindful of what muscles are contributing to motion
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Not all patients are identical – a ballet dancer will have more motion than a
factory worker
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DORSIFLEXION20
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Talus goes posterior during this motion
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Tibialils anterior, tibialis posterior, extensor hallucis longus, extensor
digitorum longus contribute
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PLANTARFLEXION50
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Has the greatest ROM
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Talus goes anterior during this motion
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Tibialis posterior, gastroc, soleus, peroneus longus and brevis, flexor hallucis
longus, flexor digitorum longus, tibialis posterior contribute
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INVERSION5
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Tibialis posterior, tibialis anterior contribute
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EVERSION5
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Fibularis group (LBT), extensor digitorum longus contributes
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ABDUCTION10
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ADDUCTION20
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Supination
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Combination of inversion, forefoot adduction and flexion
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Pronation
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Combination of eversion, forefoot abduction, and extension
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Supination and pronation are both triplanar motions
TAKING A HISTORY
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OLDCARTS
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Location of pain, severity, type of pain, alleviating and aggravating factors, radiation,
previous injury, previous surgery, meds, allergies, social history (work status), family
history, ROS
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Remember chief complaint
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Ask what meds and OTC drugs they bought
PHYSICAL EXAM
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Objective portion of SOAP
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Inversion
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Adduction
PRONATION—DEA (drug enforcement agency)
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Dorsiflexion
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Eversion
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ABduction
Includes
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Vitals, general appearance, gait evaluation, inspection, palpation, ROM, strength testing,
stability tests (anterior drawer, talar tilt), special tests, neuro and vascular status
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Be sure to check for dancer’s fracture on the fifth metatarsal
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INSPECTION
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Look at the foot and ankle
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Note areas of swelling, ecchymosis, deformity, scars, infection
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Compare both sides
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Blanching the nails should make color come back quick
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if color comes back late, may be circulatory problem
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may also indicate anemia
FUNCTIONAL ARCH ASSESSMENT
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Inspection
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Functional tests
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Forward squat test
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Have your patient squat keeping heels on the ground, and if they pronate they
have flat feet
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Assess arch pronation as well as heel cord tightness
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PES PLANUS
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Longitudinal and transverse arches fall
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Talocalcaneal joint axis is more horizontal
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Tarsal somatic dysfunction
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Navicular prominence is noted on the medial side of the foot
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PES CAVUS
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Arches rise
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Axis is more vertical
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Navicular is LESS prominent
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Is usually hereditary
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These will affect structures farther up the back
GAIT AND FOOT MECHANICS
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Heel strike happens on outer 1/3rd of heel
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You see a heel wear pattern
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Weight bearing is on lateral longitudinal arch
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Weight is transferred to 1st, 2nd, and 3rd metatarsals
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You push-off with great toe
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MAKE SURE TO ASSESS GAIT
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Remember that you have a dominant foot as well as a dominant hand
PALPATION
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Palpate specific structures: you should be able to find these, even if it takes the patient moving
the joint to find (also assess joint glide)
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Anterior
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Tibialis anterior, extensor hallucis longus and brevis, extensor digitorum,
dorsalis pedus, midfoot
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Medial
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Tibialis posterior, flexor digitorum, flexor hallucis, posterior tibial artery, deltoid
ligament
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Remember that you can have gout in the first MP joint, but also in the
ankle
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FEEL FOR PULSES
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Remember Tom, Dick, AN’ Harry
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Lateral
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Peroneus longus and brevis, ATF, CF ligaments, cuboid, 5th MT base
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Plantar
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Plantar fascia, sesamoids of 1st MTP, cuboid, MT heads, calcaneal tubercle
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Posterior
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Calcaneus and Achilles tendon
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Position and expose the patient for maximal opportunity to compare sides
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Systemic approach
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Delay the examination of the painful part until last
Anatomic knowledge is key to diagnosis
MORE ANATOMY
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Palpate the entire length of the tibia and fibula—don’t ignore superior fibula
Maisonneuve fracture is associated with syndesmotic injury
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Force moves up into the fibular head and up interosseous membrane
BONY ANATOMY
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You should be able to palpate and identify the following bony landmarks; you should note on the
SOAP note any specific areas of bone tenderness
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Tibia and fibula
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Medial/lateral malleolus
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Tarsals (7)
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Calcaneus (subtalar joint)
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Talus (ankle joint)
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Navicular
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Cuboid
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Cuneiforms
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Metatarsals
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5th MT base
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Phalanges
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MTP, IP joints
STRUCTURAL SUPPORT
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Anterior and posterior tibio-fibular ligaments maintain the mortise joint – the intact mortise
provides stability to the ankle; when these ligaments are injured, the patient has suffered a
HIGH ANKLE SPRAIN
MORTISE JOINT
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Ankle stability is increased in dorsiflexion, where the wide anterior talus fits in to the tibia/fibula
mortise
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Achilles tendon and plantar fascia can have tender points as well – pain on metatarsal
heads/march fractures happen when people are on their feet all the time
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High ankle sprains can mess up the mortise itself
ROM
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This can be done with a goniometer to be more precise
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Gross ROM testing
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Performed with pat seated
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Knees together with feet and legs exposed
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Test both active and passive ROM
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If they move more, less stable—plantarflexed ankles is a common diagnosis
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Good to do for ankle rehab—ankles need some love too!
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SWING TEST
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For talar dysfunction; can detect subtle loss of motion
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The foot is kept parallel to the floor with the knee flexed.
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If there is a plantarflexed talus (anterior dysfunction) then the foot will
plantarflex toward the ground at the barrier
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Monitoring is best done with the thumbs adjacent the anterior tendons at the ankle joint.
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Mechanics:
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For dorsiflexion to occur, the talus must dorsiflex and glide posteriorly into the
mortise with dorsiflexion of the ankle.
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If there is abnormal motion, there is said to be “anterior dysfunction of the
talus” (talus is restricted in posterior motion.)
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Compare to opposite side
PHYSIOLOGIC MOTIONS OF THE ANKLE
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STABILITY TESTING
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Anterior drawer
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tests anterior talo-fibular ligament.
Position hands as shown. Slight 5-10o plantar-flexion. Slide foot forward while
stabilizing tibia. You should feel an endpoint.
An abnormal exam would be an asymmetric increased motion or lack of endpoint. The
figure shows the direction of force. The black arrow shows the talar prominence that is
sometimes apparent at the endpoint of the drawer test.
o
Talar tilt test
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Tests the integrity of the Calcaneal Fibular Ligament.
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Second most common ligament sprained
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The hands are placed so that the right hand fingers are monitoring the space just below
the lateral malleolus.
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The talus and calcaneus are rotated toward the medial side.
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Note in the picture the distance between fingers and lateral malleolus is widened (red
circle).
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Always compare to the opposite side.
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Reverse talar tilt
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Tests integrity of Deltoid ligament.
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Essentially the reverse of the above.
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Rotation is toward the lateral maleolus.
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You are trying to rotate the talus out from under the medial maleolus.
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Deltoid ligament injuries usually require a surgical consultation.
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Note the arrow showing where monitoring should occur.
MANUAL MUSCLE TESTING
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TESTING INDIVIDUAL MUSCLES
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Subjective scale of 5
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Always compare both sides
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0 – no motion
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1 – flicker of motion
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2 – motion with gravity
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3 – motion against gravity
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4 – some resistance
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5 – full strength
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Patient should be stronger that you
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Remember inversion—tests L4
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Remember eversion—tests S1
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POSTERIOR TIBIALIS
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Test by making the patient plantarflex and invert foot
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Should see posterior tibialis tendon just anterior and inferior to the medial malleolus
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Peroneals/fibularises
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Test by having patient plantarflex and evert, resisting the examiner’s inversion force
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Peroneals may be seen tensing behind the lateral malleolus or where peroneus brevis
inserts on the 5th MT head
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Tibialis anterior testing
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Tested by having the patient hold the foot in dorsiflexion and resisting the examiner’s
plantarward force
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You should see tendon on the anterior part of the ankle
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Gastroc/soleus
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Test by toe walking
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Size and contour of both should be similar
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Also test stamina by doing a series of exercises—lack of stamina can indicate pathology
SPECIAL TESTS
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External rotation test
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Detects high ankle sprains or injuries to the anterior or posterior tibio-fibular ligaments
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Test is performed with the ankle at 90 degrees, stabilizing the leg with one hand and
forcefully externally rotating the foot on the ankle
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If the affected side opens 15 degrees greater than the normal side, the test is positive
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Also positive for injury if there is pain
Squeeze test
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Tests for high ankle sprains
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Performed by compressing the tibia and fibula together on the mid leg
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Pain is felt at the mortise joint of the ankle in a positive test
Thompson test
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Squeeze of the calf plantar flexes the foot if Achilles tendon is intact
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Done against gravity to increase sensitivity
Ankle drawer test
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Tests integrity of the anterior and posterior talofibular ligaments (also medial/lateral and
superior/deep deltoid)
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Test anterior talofibular ligament
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Patient supine, stabilize distal tibia, grasp posterior heel, slowly pull anterior
with posterior tibial counterforce
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Test posterior talofibular ligament
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Switch hands and force
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“clunking” or movement greater than 5mm is positive
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Steps
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With foot in slight plantarflexion, Dr. stabilizes tibia
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POSTERIOR DRAWER
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Dr. adds a posterior force on dorsum of foot
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Assesses posterior talofibular ligament
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ANTERIOR DRAWER
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Dr. adds an anterior force on the heel
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Assesses anterior talofibular ligament
Considered positive if there is increased laxity
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MIDFOOT PALPATION
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Twist of the midfoot injures ligaments
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Move this way to reproduce pain
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These ligaments connect navicular, cuboid, cuneiforms to proximal MTs
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Test motion of midfoot
MTP, PIP, DIP MOTION
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First MTP dorsiflexion is important for gait (push off)
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Usually at least 60 degrees
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Test MTP, PIP, DIP joint stability medially/laterally, as well as plantar/dorsally
INNERVATION
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L4-L5-S1
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Saphenous nerve, superficial and deep fibular/peroneal nerves, sural nerves
PULSES
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Posterior tibial artery and dorsalis pedis
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Posterior to medial malleolus—posterior tibial artery
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Dorsum of foot for dorsalis pedis
ANATOMY OF AN ANKLE SPRAIN
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Inversion occurs more frequently than eversion b/c of relative strength of deltoid ligament
Common mechanism of ankle sprain:
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Inversion, plantarflexion
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Anterior talofibular ligament is usually injured
Exam findings
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Edema, decreased ROM, pain at ATF, increased anterior drawer, talar tilt, positive swing
test, late ecchymosis
80% of all ankle sprains are inversion sprains
Ligament involvement includes
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Anterior talofibular ligament—TYPE I
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Calcaneofibular ligament and anterior talofibular ligament—TYPE II
Posterior talofibular ligament, calcaneofibular ligament, and anterior
talofibular ligament—TYPE III
o
INVERSION SPRAIN MECHANICS
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Eversion of calcaneus
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Posterolateral glide of talus
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Posterior fibular head
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External rotation with anteromedial glide of tibia
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Internal rotation of femur
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Posterior ipsilateral innominate
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Neutral ipsilateral sacral oblique axis (forward torsion on ipsilateral side)
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Neutral lumbar vertebrae dysfunction
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Strain can affect entire leg and be stored as somatic dysfunction at any point
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Occurs in supination
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Ligaments involved are
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Anterior talofibular
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Calcaneofibular
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Posterior talofibular
ANKLE EXAM
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Perform evaluation
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Dorsiflexion, plantarflexion, inversion, and eversion
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Note excessive inversion, which happens with history of inversion sprain, often multiple
sprains
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A tibiotalar dysfunction may cause a discrepancy in your ankle drawer test
o
ANKLE SPRAINS
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1st degree
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Ligament here are intact
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Conservative care
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2nd degree
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Partial tearing (slight laxity)
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Usually no need for surgery
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3rd degree
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Complete rupture
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Immobilization
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Surgery rarely indicated
o
Traumatic inversion strains the fibularis longus and brevis muscles
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shortening of these muscles pulls the fibula inferiorly and posteriorly
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the plantar attachment of the fibularis longus pulls the 1st cuneiform MT joint inferiorly
stressing and flattening the medial arch
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this is all compounded by the sprain of the lateral ankle ligaments to varying degrees
leading to joint instability
o
MOTION ISSUES SECONDARY TO TRAUMA
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Shape of talus
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Inversion, plantar flexion puts narrow posterior talus in the mortise joint
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Offers little stability; forces ligaments and muscle effort for stability
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Fibularis muscles
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Rapidly eccentrically loaded
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Talus jammed into joint
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Weight of body coming down ‘jams’ the talus into the crural articulation
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Talus inversion
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Anterior talofibular ligament is pulled tight
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Pulls distal fibula anterior
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Proximal fibula moves posterior and becomes locked
o
Fibular motion with gait
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Motion is anterolateral to postero-medial
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Relates biomechanics to motion deficits
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OMT can have a positive effect on acute ankle injuries in the ED.
CHRONIC VS ACUTE ANKLE SPRAINS
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Remember fibular head moves posterior during ankle INVERSION
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Fibular head moves anterior during ankle EVERSION
OTHER PROBLEMS RELATED TO THE LOWER LEG:
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Shin splints
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The complaint is usually of pain at the medial border of the tibia, the bone on the inside
of the lower leg.
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It involves degeneration and micro-tearing of the tendons of the muscles that flex the
toes and the forefoot- the flexor digitorum longus, flexor hallucis longus and tibialis
posterior.
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The usual biomechanical source of the syndrome is either functional lowering
of the longitudinal arch together with hyperpronation which is normally
compensated for by the tendons of those muscles; or through weakness and
overloading of the muscle in front of the shin, the tibialis anterior.
o
ACHILLES TENDONITIS
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The Achilles tendon represents the extension of the calf muscles into and around the
heel, into the plantar fascia, extending to the ball of the foot
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Essentially, there is a degenerative change in the tendinous region associated with
microtears
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This is the result of a combination of faulty biomechanics and repetitive
overload stress such as occurs in running
OSTEOPATHIC EVALUATION OF TALAR DYSFUNCTION
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Commonly plantarflexed
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Restricted in dorsiflexion
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AKA anterior dysfunction (posterior restriction)
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Usually due to traumatic inversion ankle injury
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Associated with plantar fasciitis
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Or chronically tight posterior calf muscles
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Patient may complain of
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Anterior talar pain
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Sense of jamming with attempted dorsiflexion
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Reduced calf stretch when attempted
DIAGNOSIS OF ANTERIOR DYSFUNCTION OF TALUS
o
Swing test
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Ankle dorsiflexion
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Involves posterior rotation and glide of the talus
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Flex knee, maintain foot parallel to ground
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Induce dorsiflexion of ankle
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Anterior talus will cause foot to point plantar-ward at the barrier
PLANTAR FASCIA:
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The function of the plantar fascia is to provide static support for the longitudinal arch of the foot
and to assist with shock absorption during foot strike.
o
During the heel-off phase of gait, tension increases on the plantar fascia, which acts as a storage
of potential energy.
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During toe-off, the plantar fascia passively contracts, converting the potential energy into kinetic
energy and imparting greater foot acceleration.
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Plantar fasciitis
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This condition causes pain by inflammation of the insertion of the plantar fascia on the
medial process of the calcaneal tuberosity
PES PLANUS
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Longitudinal and transverse arches fall
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Subtalar arch is more horizontal
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There is tarsal somatic dysfunction
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Navicular is prominent on the medial side of the foot
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Plantar fasciitis may be seen from decreased ligamentous arch stability (flattened arches)
OMT
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Test glide (talus on calcaneus) in an anteromedial/posterolateral direction as limited by
talocalcaneal ligament:
Somatic dysfunction is named for the direction it wants to go
Eversion—anteromedial shift
Inversion—posterolateral shift
IN PLANTAR FLEXION SOMATIC DYSFUNCTION
TEST:
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Patient is supine with examiner at feet
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Grasp metatarsal heads and dorsiflex feet bilaterally
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Compare left and right for relative restrictions in dorsiflexion
o
TREAT FIBULA BEFORE ANKLE AND FOOT!
o
OMT—TALAR TUG
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Patient supine, leg extended, operator at end of the table
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Operator grasps foot and curls 5th finger around head of talus, the other 5th finger
reinforces
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Remaining fingers are across dorsum of foot with both thumbs on plantar surface of foot
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The ankle is now dorsiflexed to engage the restrictive barrier
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Maintain steady caudal traction at the ankle joint
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Corrective force is short, quick, caudal HVLA thrust carried from the 5th fingers through
the talus
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RECHECK
TALOCALCANEAL DYSFUNCTION
o
ARTICULATORY TECHNIQUE WITH TRACTION
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Patient is seated at the end of the table with legs dangling
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Operator grasps heel with one hand and dorsum of foot near ankle with other hand
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Traction is exerted by a downward pull on the calcaneus while the other hand articulates
the talocalcaneal joint through its full range of inversion and eversion—CIRCULAR
MOTIONS IN BOTH DIRECTIONS
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RECHECK
SOMATIC DYSFUNCTION—TRANSVERSE ARCH
o
SUPINE DIRECT ARTICULATORY TECHNIQUE WITH PATIENT COOPERATION
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Patient supine with operator at the end of the table
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Contact the area over the cuboid and navicular bones by crossing your thumbs and
grasping dorsum of foot
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Apply tension to separate the components of the transverse arch
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Encourage a normal arch, by taking up the slack to approach the barrier
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Have patient plantarflex while operator applies a counterforce with their thumbs
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Take up the slack as per ME protocol, engaging the new barrier
o
PLANTAR HISS WHIP—DYSFUNCTIONAL CUBOID, NAVICULAR, CUNEIFORM
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A flexion/extension motion is instituted by swinging the limb toward and away from the
knee
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o
o
TALUS
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Notice the increase in resistance at the point when the femur is perpendicular to the
ground – this is the point where the thrust will be directed
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For cuboid, thrust is slightly lateral
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For navicular, thrust is slightly medial
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For cuneiform, thrust is straight down
Patient is prone with leg hanging off the table
Operator grasps foot with dysfunction
Place one thumb over specific bone to be treated (navicular, cuboid, cuneiform)
Reinforce with opposite thumb
Interlace fingers on dorsum of foot