Trauma Skeletal Radiology - Dani's EDyazdani.co.uk/wp-content/uploads/2016/05/foot.pdf · Trauma...
Transcript of Trauma Skeletal Radiology - Dani's EDyazdani.co.uk/wp-content/uploads/2016/05/foot.pdf · Trauma...
Trauma Skeletal Radiology
A Practical Guide
Foot
L J Brimicombe
Clinical Specialist
Skeletal Radiology
FOOT
Systematic Film Evaluation
Alignment
Bones
Cartilage
Soft Tissue
Evaluate the ABC’S!
Alignment
Bowing
Normal position
of bones
Spaces between
bones
Symmetry
Angulations
Bones
Anomalies in the cortex, breaks, overlaps &
steps.
Changes in trabecular pattern
Changes in densities
Periosteal Reaction
Cartilage
Look for avulsion
fractures
Misalignment
Effusions
Soft Tissue
1. Defect on normal contours
2. Obvious swelling
3. Foreign body (e.g. glass) in
soft tissues
4. A fluid/solid interface
5. A gas/fluid interface
FOOT FOREFOOT
– Metatarsals' + Phalanges
MIDFOOT – Navicular, Cuboid +
– Lat, Middle & Medial Cuneforms
HINDFOOT – Talus + Calcaneum
Foot Anatomy
Foot Anatomy
Foot Anatomy
Ossification Centres
Calcaneus, talus - at birth
Cuboid - after birth
Lat Cuneform - about 1 yr
Med Cuneform - about 2yrs
Middle Cuneform - about 3yrs
Navicular - 5yrs
Epiphysis at the base and head of the phalanx centres appear about 4yrs and fuse at 18yrs
Dislocation of phalanx
Metatarsal Fracture
5th Apophysis & Fracture
March/Stress Fracture
Peroneus Brevis
Avulsion fractures are
common at the tuberosity
at the base of 5th
metatarsal.
This is at the insertion of
the peroneus brevis
tendon
Avulsions occur due to
inversion injuries
Jones Fracture >1.5 cm distal to 5th MT tuberosity
•Poorer prognosis than avulsion fractures
•Requires non-weight bearing treatment
Children's 1st metatarsal injury
LisFranc Fracture Dislocation
Lisfranc injury is a fracture at the base of the 2nd metatarsal with subluxation laterally from the tarso-metatarsal joint
Most common foot dislocation
20% missed on initial plain films
Trauma but also associated with charcot
Normal Foot Alignment
AP OBLIQUE OBLIQUE
Lisfranc Fracture Dislocation
Cuneform Fractures – wedge shaped
Cuboid Fracture
Avulsion Fracture Nutcracker Fracture
Navicular Fracture
Navicular
Latin for boat shape
Scaphoid like bone
Avulsions of Navicular & Talus
Avulsion fractures of the dorsal surface of the navicular and head of talus are common and often missed. These can only be identified by a lateral view:
Talus Aviators Astragalus
Talus – Latin Astragalus – Greek
1919 Anderson, consulting surgeon to the Royal Flying
Corps in WW1 described 18 cases of fracture and
dislocation of the talus. The association of injuries of
the talus with aircraft crash was so strong that he
named them “Aviator’s Astragalus.”
Fractures include compression fractures of the talar
neck, fractures of the body, fractures of the posterior
process, or fracture dislocation injuries
Talus - Aviators Astragalus
Talar neck is the most frequently injured site
The talus is the second most injured bone in the foot
Talus - Aviators Astragalus
Avascular necrosis
is a potential
complication of
neck fractures
Talus Posterior Pole # - Snowboarders!
Subtalar Dislocation Basketball Disloc.
Calcaneum – Most common fractured tarsal
Calcaneum – compression
Bohler’s Angle not within
normal limits
Calcaneum – Anterior Process
Bifurcate ligament:
Connects the anterior process of the
calcaneus to both the cuboid and
navicular
Inversion stress of the foot will result
in stretch of this ligament or avulsion
fracture of the anterior process
Calcaneum Avulsion
A 2nd common site is seen
lateral to the calcaneum
Only seen on a foot x-ray
At the insertion of the extensor
digitorum brevis muscle
Accessory Ossicles Posterior
1= Os cuneometatarsale I plantare
2= os uncinatum
3= os sesamoideum tibialis posterior
4= os sesamoideum peroneum
5=os cuboideum secundarium
6=os trochleare calcanei
7=os in sinus tarsi
8=os sustentaculum tali
9=os talocalcaneale posterius
10=os aponeurosis plantaris
11=os subcalcaneum
More Accessory Ossicles - Anterior
12=os sesamoideum tibialis anterior
13=os cuneometatarsale tibiale
14=os intermetatarsale
15=os cuneometatarsale dorsale
16=os paracuneiforme 17=os cuneonaviculare
18=os intercuneiforme 19=os intermetatarsale
20=os talonaviculare 21=os vesalianum pedis
22=os tibiale externum 23=os talotibiale dorsale
24=os supratalare
25=os calcaneus secundarius
26=os subtibiale 27=os subfibulare
28=os retinaculi
29=os calcaneus accessorius
30=os trigonum 31=os supracalcaneum
32=os tendinis calcanei
Most Common Accessory Ossicles
Usually originate from
secondary centres of
ossification that do not
unite with the main
centres
Differentiated from
fractures:
- bilateral presentation
- smooth rounded well
and corticated border
Os Naviculare
Os Tibiale Externum
Os Peroneum
Os Trigonum
Osteochondritis Dissecans
Seen in young athletic people in trauma
• Subchondral bone below the articular
cartilage loses its blood supply
• The bone and its overlying cartilage
become damaged, a fragment of bone
may separate to form loose bodies in
the joint
• The process occurs particularly in the
femoral condyles of the knee, and also
in the talus and hip joints
Charcot Neuro-osteoarthropathy
A degenerative disease with progressive
destruction of the bones and joints.
It is seen in patients with neurological disorders
with sensory loss of the feet, including tabes
dorsalis, leprosy, diabetic neuropathy, and
other conditions involving injury to the spinal
cord.
Charcot Foot
In the early stages radiographic abnormalities
are not present.
The acute stage of Charcot neuro-
osteoarthropathy shows rapid and progressive
bone and joint destruction within days or
weeks.
Immobility by total contact casting can prevent
further bone and joint destruction.
On the right an image of a patient with diabetic
neuropathy and a red hot foot. Normal x-rays
may not exclude the diagnosis of acute
Charcot neuro-osteoarthropathy.
Within 4 months there is progressive decrease
of calcaneal inclination with equinus deformity
at the ankle. Destruction of the tarsometatarsal
joint is seen, with the typical rocker-bottom
deformity.
Charcot Foot
Progressive neuro-
osteoarthropathy of
the tarsometatarsal
joints.
Lisfranc dislocation
subchondral cysts
erosions,
.
Pitfalls - Foot
Over penetration for toes
Cutting the soft tissue off
X-raying the whole foot when a toe is specified
Over turning oblique's so the metatarsals
overlay each other
Questions?