Q8-3. Fascia of the Foot Flashcards
What is the difference between the superficial fascia on the dorsum and that on the sole?
Dorsum: little fat
Sole: thick, fat-filled in key weight-bearing areas (toes, ball of foot, lateral side, and heel)
where are the areas of thicker superficial fascia on the plantar foot?
what do these spaces correlate to?
- thicker SF:
- lateral margin of heel
- proceeds to MT5, then medial MTs,
- lateral toes and hallux
- correlate w/ the pressure distribution during gait
what separates superficial fascia (SF) on dorsum from SF on the sole?
fusion of the deep fascia (DF) to the dermis
what is continuous with the deep fascia of the foot?
crural fascia
the deep fascia of the foot and the crural fascia contributes to the formation of what?
retinacula
(a band around tendons that holds them in place)
name of the deep fascia on the dorsum of the foot?
fascia dorsalis pedis
*between which layers are the TA, EHL, EDL, and FT?
between superficial and deep layers of the deep fascia
the deep layer of the deep fascia splits to enclose which muscles?
- extensor digitorum brevis and
- extensor hallucis brevis
what contents run between the deep fascia and the bone?
- dorsalis pedis artery
- terminal branches of deep fibular nerve
What is the deep fascia called on the sole of the foot?
plantar fascia/
plantar aponeurosis
what are the divisons of the plantar aponeurosis?
medial,
central,
lateral
medial plantar aponeurosis:
prox and distal attachments
- prox:
- continuous w/ flexor retinaculum, & (?) medial process of calcaneal tuberosity
- distal:
- medially: fascia dorsalis pedis
- laterally: central plantar aponeurosis
lateral PA:
prox and distal attachments
- proximal:
- lateral process of calcaneal tuberosity
- distal:
- medially: central plantar aponeurosis
- laterally: fascia dorsalis pedis
calcaneometatarsal ligament:
define
thick band of lateral plantar aponeurosis;
passes from lateral process of calcaneus to MT 5 tuberosity
which division of the plantar aponeurosis is the strongest?
central PA
central plantar aponeurosis:
attachments and divisions
- prox: medial process of calcaneal tuberosity
- divisions *@ midtarsal level
- linked via transverse extensions of connective tissue to keep them properly aligned w/ each other and long axis of foot
at level of the MT head, each digitation splits into a…
- superficial slip/tract
- deep slip/tract
superficial slip/tract:
define
- contributes to the formation of the superficial transverse metatarsal ligament (STML)
- then attaches to the dermis
deep slip/tract:
define
- Divides into 2 parts that lie on either side of the flexor tendons (forming flexor sheaths of lateral toes; attaching to sesamoids of hallux)
- Pass deep/dorsally to connect to the:
- plantar metatarsophalangeal ligament/plantar pad or plate
- deep transverse MT ligament
- base of proximal phalanx
what simple machine is the plantar aponeurosis compared to?
in what ways does it act like this machine?
- compared to windlass/pulley system
- actions
- initated by heel rise
- MTPJs passively dorsiflex
- w/ passive dorsiflexion –> deep digital slips attached to the bases of the PPs are wound around their respective MT heads
- winding tightens the PA, causing osseous compression in the midfoot –> raising the MLA and creating midfoot joint stability needed for propulsion on weight-bearing foot
the medial plantar aponeurosis both covers and provides partial origin to which muscle?
abductor hallucis
The central plantar aponeurosis both covers and provides partial origin to which muscle?
flexor digitorum brevis (FDB)
The lateral plantar aponeurosis both covers and provides partial origin to which muscle?
abductor digiti minimi (ADM)
what separates the 3 portions of the plantar aponeurosis?
grooves created by septa running between plantar aponeurosis and bone;
- medial intermuscular septum
- lateral intermuscular septum
characteristics of the intermuscular septa running between plantar aponeurosis and bone?
- septa are relatively thin, irregular sheets perforated for the passage of tendons and neurovascular structures
what are the components creating the 3 major osteofascial compartments?
- bones
- plantar aponeurosis
- septa
intrinsic muscles of foot:
medial compartment
- abductor hallucis
- flexor hallucis brevis (*could be in central compartment)
intrinsic muscles of foot:
central compartment
- Flexor Digitorum Brevis
- Quadratus plantae
- Lumbricals
- Adductor hallucis
intrinsic muscles of foot:
lateral compartment
- Abductor digiti minimi
- Flexor digiti minimi brevis
what separates the deeper/more superior interosseous compartment from the central compartment?
interosseous fascia
contents of the interosseous compartment of the plantar foot
- 4 dorsal interossei (DABs)
- 3 plantar interossei (PADs)
although there are many variations of compartments of extrinsic muscles, what was the one example Dr. G provided?
5 compartments
- medial compartment of sole
- central compartment of sole
- lateral compartment of sole
- interosseous compartment of foot
- dorsal compartment of foot
extrinsic muscles of:
medial compartment (example)
- abductor hallucis
- flexor hallucis brevis
- FHL tendon
- medial planar nerve & vessels
extrinsic muscles of:
central compartment (example)
- Flexor Digitorum Brevis
- FHL tendon
- FDL tendon
- Quadratus plantae
- Lumbricals
- Adductor hallucis
- Lateral Plantar Nerve & Vessels
extrinsic muscles of:
lateral compartment
- Abductor digiti minimi brevis
- Flexor digiti minimi brevis
extrinsic muscles of:
interosseous compartment
- MTs
- Dorsal & Plantar Interossei
- Deep plantar & MT vessels
*note, interosseous compartment is located in the forefoot only
extrinsic muscles of:
dorsal compartment
- Extensor hallucis brevis
- Extensor digitorum brevis
- Branches of the dorsalis pedis & deep fibular/peroneal nerve
*Draves (1986) subdivides this compartment into 3 layers based on splitting of the deep fascia as detailed on slide 4 of this conference
a puncture wound or perforating ulcer can penetrate where and cause what?
can penetrate deep central plantar spaces,
leading to abscess/ deep infection of the foot
CC: deep infections of the foot
symptoms and sequelae if left untreated
- sxs, esp along instep:
- swelling
- pain
- erythema (redness, rash)
- if untreated –>
- can spread proximally to the posterior compartment of the leg
extrinsic muscles of:
central compartment
- Flexor Digitorum Brevis
- FHL tendon
- FDL tendon
- Quadratus plantae
- Lumbricals
- Adductor hallucis
- Lateral Plantar Nerve & Vessels
CC: compartment syndrome of foot;
diagnosis
- sxs
- increasing pain, exaggerted by toe stretching
- swelling w/ loss of skin wrinkling
- neurovascular deficits
- May use needle stick measurements in unconscious patients
CC: compartment syndrome of foot;
treatment, and sequelae if left untreated
- treatment: emergeny fasciotomy to release interosseous compartments
- sequelae if left untreated:
- chronic pain
- numbness
- deformities like rigid claw and hammer toes
- plantar muscle atrophy
- callus formation
- cavus foot
CC: compartment syndrome of foot;
cause
high energy injuries to the foot;
can also lead to compartment syndrome of the leg (e.g. calcaneal fracture)
