06/03/2021 [hand/foot bones, vagina disease, radiology, stomach anatomy, SVT] Flashcards
Three bone types in the hand
Carpal bones [x8]
Metacarpals [x5]
Phalanges [x14]
= 27
Name the carpals in the hand
Some Lovers Try Positions They Can’t Handle:
[Scaphoid, Lunate, Triquetral, Pisiform, Trapezium, Trapezoid, Capitate, Hamate]. Split into distal 4, and proximal 4.
What do the carpal bones form?
Collectively, they form the coronal plane
What covers the carpal bone?
The flexor retinaculum [carpal tunnel]
What forms the wrist joint?
The proximal carpals [scaphoid and lunate] articulating with the wrist joint.
Typical cause and clinical features of a scaphoid fracture
Cause: falling on an outstretch hand [FOOSH]
Feature: pain and tenderness in the anatomical snuffbox.
Particular risk of a scaphoid fracture? Why is this so?
Avascular necrosis; retrograde blood supply to scaphoid which enters distal end.
Pts with missed scaphoid fracture more likely to develop OA later in life.
What are the two common fractures of the metacarpals?
Boxer’s fracture: fracture of the 5th metacarpal neck; usually caused by clenched fist striking a hard object. Distal part of the fracture disaplced anteriorlty, producing shortening of the affected finger.
Bennett’s fracture: fracture of the 1st metacarpal base, caused by forced hyperabduction of the thumb.
Why are the metacarpals concave?
To allow the attachement of the interossei muscles.
How many phalanges in each finger/thiumb?
x3 fingers, x2 thumb
Three groups of bones in the foot?
Tarsals [x7]
Metatarsals [x5]
Phalanges [x14]
= 23 [though apparently 26?]
How are the the tarsal bones organised?
- Proximal group or hind-foot [talus and calcaeneus]
- interrmediate group [the navicular]
- Distal or midfoot [cuboid and cuneiforms]
What are the articulation of the talus in the hindfoot?
- Superiorly: ankle joint [talus and bones of the leg [tibia and fibula]
- Inferiorly: subtalar joint [talus and calcaneus]
- Anteriorly: talonavicular koint [talus and navocular]
Why is there a high risk of avascular necrosis to the talus?
Numerous ligaments attach tot he talus, no muscles originate or insert onto it. So high risk of AN as vascular supply dependent on fascial structures.
Articulations of the calcaneus. Also, what is it?
It is the largest tarsal bone lies underneat the talus where it constitutes the heel.
Articulations:
- superiorly: subtalar joint
- anteriorly: calcaneocuboid joint
Where does the Achilles tendon attach on the foot?
Posterior aspect at the calcaneus tuberosity.
Where does the tibialis posterior attach to the foot?
Plantar surface of the navicular, tuberosity for the attachment of the tendon.
Distal group bones in the foot
Cuboid, three cuneiforms [lateral, intermediate, medial].]
Which muscles attach to the distal tarsals?
Medial cuneiform - tibialis anterior [tibialis posterior and fibularis posterior and longus]
Lasteral cuneiform - flexor hallucis brevis
Commonest fracture types foot
Talus and calcaenues [as where forces transmitted to the ground]
When do talus fractures typically occur?
Neck fractures to the talus; high energy dorsiflexion of the foot.
Body fractures typically occur jumping from high height.
Danger of talus fractures
Avascular necrosis
When is the calcaneus typically fractured?
Axial loading, typically falling from a height.
In axial loading, what should patients also be assessed for?
Associated injuries siuch as fractures of the lumbar spine/lower limb.