What muscles lay in the first layer of the foot?
Abductor hallucis, flexor digitorum brevis, abductor digiti minimi
What muscles lay in the second layer of the foot?
Quadratus plantae, lumbricals (flexor digitorum longus and flexor hallucis longus pass through this layer)
What muscles lay in the third layer of the foot?
flexor hallucis brevis, adductor hallucis, flexordigit minimi brevis
What muscles lay in the fourth layer of the foot?
Plantar interossei and dorsal interossei (peroneus longus and tibilias posterior pass through this layer)
How much ROM is require for normal gait?
20-30 degrees of PF and 6-10 of DF
What is the windlass mechanism of the foot?
Toe DF produces supination and thereform creates a medial longitudinal arch
What are the four common arches of the normal foot?
Medial (formed by calcaneus, talus, navicular, & 3 cuneiforms) and lateral calcaneus, cuboid( metatarsals 4&5) longitudinal arch; proximal (navicular, three cunieforms, & cuboid) and distal (5 metatrasal) transverse
What is pes planus?
a foot that exhibits no longitudinal arch and an ankle that is everted (valgus); there is rigid (caused by tarsal coalition, verticle talus) and flexible
What is pes cavus?
high arch; may be related to muscle imbalances – toe walkers with tight tight tendo achilles and limited DF or neuromucular disease
What percentage of weight does the fibula bear?
Describe the function of the deltoid ligament?
prevents eversion and abd of the talus; higher potential to avulse secondary to strength
What are the lateral collateral ligaments of the foot?
ant talofibular, post talofibular, calcaneofibular; ATF most commonly sprained with inv injury with PF
Define Lisfranc's ligament:
tarsometatarsal spanning from the medial cuneiform to the base of the second metatarsal; can avulse
What is the spring ligament:
Calcaneonavicular ligament from the plantar aspect of the sustentaculum tali to the navicular; primary static stabilizer of the medial longitudinal arch
What is chopart's joint:
midtarsal joint: talonavicular and calcaneocuboid
How does a widening of the motise after a syndesmotic injury change the WB'ing surface of the ankle?
1 mm increase decrease the WB'ing surface by 40%; 3 mm >60%, 5mm ~80%; will increase likelihood of early degerative joint disease
What increases the risk for anterior talus impingement?
osteophytes, scar tissue, or overly compressed ORIF
What is the sinus tarsi?
opening between the talus and calcaneus
What are the contents of the tarsal tunnel?
Tom, Dick, And Very Nervous, Harry; T – posterior Tibial Tendon; D – Flexor Digitorum longus; ANV – posterior tibial artery, vein, and nerve; H – flexor hallucis longus
What are the 5 nerves that cross into and supply motor and sensory fibers to the foot?
1.) sural nerve (post lat) 2.) Superficial peroneal nerve (ant lat) 3.) deep peroneal nerve (ant) 4.) saphenous nerve (ant med) 5.) post tibial nerve (post med)
Define porta pedis
anatomic opening on the plantar surface of the foot that medial and lateral plantar nerve and compression of the plantar nerves
What structure is referred to as the “freshman's nerve”
plantaris tendon which attaches onto the medial aspect of the posterior calcaneus tuberosity
What is meant by an accessory bone of the foot?
An ossicle or bone that separates from the normal bone (most commonly caused by fracture or a secondary ossification center)
What is the function of the seasmoids?
transfer loads through the soft tissues to the metatarsal head and increase the lever arm of the flexor hallucis brevis to aid in push off
what effect does hallux valgus increase have on PF force at push off?
angle of 40 degrees decreases push off strength by 78%
How many muscles attach to the talus?
What is the difference between achilles tendonitis and tendonosis?
Tendonitis is an inflammatory process casued by overuse activities or a specific disease process; tendonosis is beyond the inflammatory stage where the tendon has failed to heal, with possible thickening of the tendon
Other differential Dx for achilles complex?
insertional tendinopathy and inflamed retrocalcaneal bursa
What treatments are there for achilles tendonitis and tendonosis?
Heel lifts, NSAIDs, eccentrics