Lower Limb Bones Flashcards
What is the name of the only bone in the thigh? What type of bone is it?
Femur
Long bone (longest in the body)
What is the main function of the femur?
Transmits force from the tibia to the hip joint
The femur can be divided into which three portions?
Proximal
Shaft
Distal
The proximal area of the femur articulates with the…
Pelvis to form the hip joint
Name 6 landmarks on the proximal femur
Head Neck Greater trochanter Lesser trochanter Intertrochanteric line Intertrochanteric crest
What sort of structures are the greater and less trochanters?
Bony processes
The head of the femur articulates with…
The acetabulum of the pelvis to form the hip joint
What is the purpose of the depression on the medial aspect of the head of the femur?
For the attachment of the ligament of head of femur
The neck of the femur connects the head of the femur with the…
What shape does it have?
In which direction does it project?
What is the purpose of this angle?
Shaft
Cylindrical
Superomedially
Allows increased range of movement at the hip joint
What is the greater trochanter? Where is it located?
A projection of bone on the femur that originates from the anterior aspect just lateral to the neck of the femur
Can the greater trochanter be found on both the anterior and posterior sides of the femur?
Yes
Which muscles attach at the greater trochanter?
Many muscles of the gluteal region
Gluteus medius
Gluteus minimus
Piriformis
Where is the lesser trochanter?
Projection on the posteromedial side of the proximal femur - just inferior to the neck/shaft junction of the femur
Which muscles attach at the lesser trochanter?
Psoas major
Iliacus muscles
What is the intertrochanteric line?
A ridge of bone on the anterior surface of the femur connecting the two trochanters
When is the intertrochanteric line known as the pectineal line?
After its passes the lesser trochanter on the posterior surface
What structure attaches at the intertrochanteric line?
Iliofemoral ligament
What is the intertrochanteric crest?
Ridge of bone that connects the two trochanters on the posterior surface of the femur?
Where is the quadrate tubercle? Which muscle attaches here?
On the superior half of the intertrochanteric crest
Quadratus femoris
Fractures of the proximal femur can be classified into which two main groups?
Intracapsular fractures
Extracapsular fractures
In which group of people are intracapsular fractures of the proximal femur most common? What can cause them?
Elderly - especially women
A minor trip or stumble
What is a intracapsular fracture of the proximal femur? Which vessel can be damaged by this type of fracture? What complications can this have to the femur?
Fracture that occurs within the capsule of the hip joint
Femoral circumflex artery
Can result in avascular necrosis of the femoral head
What happens to the distal fragment of bone in an intracapsular fracture of the proximal femur? How does this clinically present?
Puller upwards and rotated laterally
Shorter leg length with toes pointing laterally
Extracapsular fractures of the proximal femur are common in which group ages of people?
Young
Middle aged
How does an extracapsular fracture of the proximal femur affect the blood supply to the femoral head?
Does not affect the femoral circumflex artery, so blood supply is intact and no avascular necrosis can occur
What are the clinical features of an extracapsular fracture of the proximal femur?
Same as intracapsular fractures
Toes pointing laterally
Shorter leg length
The shaft of the femur descends in a slightly _________ direction
What is the reason for this?
Medial
Knees closer to the centre of the body - increased stability
Where are the linea aspera located on the femur?
Down the posterior surface of the femoral shaft
What are the linea aspera?
Roughened ridges of bone on the posterior surface of the femoral shaft
Proximally, what does the lateral border of the linea aspera become?
What does the medial border become proximally?
Gluteal tuberosity
Pectineal line
What attaches at the gluteal tuberosity?
Gluteus maximus
What does the linea aspera form distally?
Widens and becomes the floor of the popliteal fossa
Medial border becomes medial supracondylar line
Lateral border becomes lateral supracondylar line
What muscle attaches at the adductor tubercle? Where is this located?
Adductor magnus
Where the medial supracondylar line stops
Are fractures of the femoral shaft relatively common or uncommon? Why? What typically causes them?
Uncommon
Requires a lot of force
Traumatic injury - e.g. Car crash
Femoral shaft fractures often occur as a _______ fracture which causes…
Spiral
Leg shortening
What causes the leg shortening seen in fractures of the femoral shaft?
The overriding of bony fragments of the femur as they are pulled by their attaching muscles
Which neurovascular structures be damaged in a high energy injury that is the fracture of the femoral shaft?
Femoral artery or femoral nerve
The distal end of the femur articulates with which bones to form the knee joint?
Tibia
Patella is
How do the medial and lateral condyles articulate?
Posteriorly and inferiorly articulate with the tibia and menisci of the knee
Anterior surface articulates with the patella
What are the medial and lateral epicondyles? What attaches here?
Bony elevations on the non-articular areas of the condyles
Various muscles and collateral ligaments of the knee
What is the intercondylar fossa? What is its function?
Depression between the medial and lateral condyles on the posterior surface of the femur
Contains 2 facets for attachment of internal knee ligaments
Where is the facet for attachment of the posterior cruciate ligament found?
On the medial wall of the intercondylar fossa
Where is the facet for the attachment of the anterior cruciate ligament found?
On the lateral wall of the intercondylar fossa
What is anther name for the patella? Where is the patella located?
Kneecap
Front of the knee joint in the patellofemoral groove of the femur
The patella attaches superiorly to which tendon?
Quadriceps tendon
The patella attaches inferiorly to which ligament?
Patella ligament
What type of bone is the patella? What rough shape does it have? What surfaces does the patella have?
Sesamoid bone
Triangular
Anterior and posterior
Where is the apex of the patella located? Where is the base of the patella located?
Apex - inferiorly
Base - superiorly
The apex of the patella is connected to the ___________ _____________ by the ___________ ligament
Tibial tuberosity
Patellar ligament
The base of the patella provides attachment for the…
Quadriceps tendon
The posterior surface of the patella consists of 2 _________ and articulates with the…
Facets
Femur
What does the medial facet on the posterior surface of the patella articulate with?
With the medial condyle of the femur
What does the lateral facet of the posterior surface of the patella articulate with?
With the lateral condyle of the femur
What are the two main functions of the patella?
Leg extension
Protection
What happens in patellar dislocation? In what direction does it usually dislocate? What commonly causes patellar dislocation?
Patella is displaced out of the patellofemoral groove
Laterally
High force impact on the patella or sudden twisting of the knee (common in sports)
What usually causes patellar fracture? In what groups of people are they most common?
Direct trauma or sudden contraction of the quadriceps muscle
Ages 20-50, males
What will happen if the patella fragments into proximal and distal fragments upon patellar fracture?
Proximal fracture will be pulled superiorly by quadriceps tendon
Distal fragment will be pulled inferiorly by the patellar ligament
What is the main bone of the leg?
The tibia
The tibia is more commonly known as the…
At its distal end it attaches to the…
At its proximal end it attaches to the…
Shin
Ankle
Knee
What is an important main function of the tibia?
Acts as a weight bearing structure
What is the tibial plateau? Where is it located?
A flat surface formed by the medial and lateral condyles on the proximal tibia
The tibial plateau articulates with the…
Femoral condyles to form the major articulation of the knee joint
What is the region between the two condyles of the proximal tibia called?
Intercondylar eminence
What does the intercondylar eminence consist of? What attaches here?
Two tubercles
Ligaments and the menisci of the knee joint
The tibial intercondylar tubercles fit into…
The intercondylar fossa of the femur
Where is the tibial tuberosity located? What attaches here?
On the anterior surface of the proximal tibia, inferior to the condyles
Patella ligament
The shaft of the tibia consists of how many borders and surfaces?
3 borders
3 surfaces
Anterior, Posterior, Lateral
Which structure on the tibia marks the start of the anterior border?
Tibial tuberosity
Which border of the tibial shaft can be palpated on the body as the ‘shin’?
Anterior border
What causes clinical presentations of bruising in the shin area?
Damage to the periosteal covering of the tibia
What is the soleal line? Where on the tibia does it run? Where does it end? What muscle originates where the soleal line ends?
Ridge of bone which marks the posterior surface of the tibia
Runs inferomedially
Medial border of the tibia
Soleus muscle
What is another term for the lateral border of the tibia? What attaches here?
Interosseous border
Interosseous membrane which binds the tibia and fibula
What happens to the shape of the tibia at both the proximal and distal ends?
What is the purpose of this?
It widens
Aids with weight bearing
What is the name given to the bony projection on the medial side of the distal tibia?
Medial malleolus
What does the medial malleolus articulate with?
The tarsal bones to form part of the ankle joint
What is the function of the groove on the posterior surface of the distal tibia?
Where the tibialis posterior muscle attaches (space for the tendon)
What is the fibular notch? What happens here?
Notch on the the lateral side of the distal tibia
Fibula is bound to the tibia
Are fractures of the tibia relatively common or uncommon? In what groups of people do they normally occur?
Common
Middle aged and elderly
If the fibula is not fractured how are fragments of the fractured tibia displaced?
Minimally as the fibula will support the tibia
Which site on the tibia is most vulnerable to fracture? What is a common cause of this? What consequences can result?
Proximal end
Traumatic accident
Condyles may be broken up, ligaments of the knee may be damaged
The medial mallelolus can be fractured. What is the cause of this? What type of fracture results?
Over-inversion of the ankle - talus of foot forced against medial malleolus
Spiral fracture
What is the position and thickness of the fibula compared to the tibia?
Located laterally to the tibia
Much thinner than the tibia
What is the main function of the fibula? Why is it not as important as a weight bearer?
Attachment for muscles
Does not articulate with the femur at the knee joint
What structures are present at the proximal end of the fibula?
Head containing a facet for articulation with the lateral condyle of the tibia
Neck
How does the fibula articulate with the tibia at its proximal end?
Facet of the head of the fibula articulates with the lateral condyle of the tibia
Where on the fibula can the common fibular nerve be found?
Posterior and lateral surface of the fibular neck
The fibular shaft consists of which surfaces?
Anterior, lateral and posterior
What is the continuation of the lateral surface of the distal fibula called?
The lateral malleolus
Which is more prominent, the lateral or medial malleolus?
Lateral malleolus
Can be palpated at the lateral ankle
What part of the fibula is most prone to fracture?
The lateral malleolus
Fractures of the lateral malleolus can be of which two types? Which is more common?
Spiral - more common
Transverse
What causes a spiral fracture of the fibula?
Forced external rotation of the ankle
Force of the talus against the lateral malleolus causes fracture
What causes a transverse fracture of the fibula?
Foot being twisted outwards (eversion)
Talus presses against the lateral malleolus causing fracture
The bones of the foot can be divided into which three categories?
Tarsals
Metatarsals
Phalanges
How many tarsal bones are there? In which area of the foot are they located?
7
Ankle
How many metatarsals are there in the foot? What do they connect?
5 - one for each digit
Phalanges and the tarsals
Phalanges are the bones of the _______
How many phalanges does each toe have?
Toes
Each toe has three phalanges except the big toe which has two
The tarsal bones of the foot are organised into how many rows?
3
Proximal, Intermediate, Distal
What are the proximal tarsal bones?
Talus
Calcaneus
Which is the most superior tarsal bone?
Talus
How many articulations does the talus have? Describe them.
3
Superior - ankle joint - tibia and fibula
Inferior - subtalar joint - calcaneous
Anterior- talonavicular joint - navicular
What is the main function of the talus?
To transmit forces from the tibia to the calcaneus
What is another name for the calcaneus?
The heel bone
Do any muscles attach or originate at the talus?
No - only ligaments attach here
What is the position of the calcaneus relative to the talus?
Located underneath the talus
How many articulations does the calcaneus have? Describe them.
2
Superior - subtalar joint - talus
Anteriorly - calcaneocuboid joint - cuboid
What is the function of the calcaneus?
Transmits forces from the talus to the ground
What marks the posterior aspect of the calcaneus? What attaches here?
Calcaneal tuberosity
Achilles tendon
How many bones are present in the intermediate group of the tarsals?
1 - Navicular
How many articulations does the navicular make? With which bones?
3
Posteriorly - talus
Anteriorly - cuneiform bones
Laterally - cuboid
Where on the navicular is a tuberosity present? What attaches here?
Plantar surface
Tibialis posterior tendon
How many bones are there in the distal group of tarsal bones? Name them.
4
Cuboid
3 Cuneiforms
Where is the cuboid located in the distal row of the tarsal bones? What does it articulate with?
Most laterally
Posteriorly - calcaneus
Anteriorly - 2 metatarsals
A groove is present on which surface of the cuboid? What is it for?
Inferior surface
Fibularis longus muscle
How many cuneiform bones are there? How are they named? What shape do they take?
3
Lateral, Intermediate, Medial
Wedge shaped
Where do the cuneiform bones articulate?
Posteriorly - navicular
Anteriorly - 3 metatarsals
The shape of the cuneiforms contributes to…
The transverse arch that exists across the foot
What are the two most commonly fractured tarsal bones?
Talus
Calcaneus
Fractures of the talus can occur in which two places?
Neck or body of the talus
What causes neck fractures of the talus? What complications can occur in this type of talus fracture?
Excessive dorsiflexion of the foot - neck of the talus pushed against the tibia
Interrupted blood supply - avascular necrosis of the talus
What usually causes fractures of the talus body?
Jumping from a height
Why is there little displacement of fracture pieces in any fracture of the talus?
The malleoli of the leg bones act to hold the fragments together
The calcaneus is often fractured in which sort of injury? What causes the fracture?
A crush type injury - e.g. Falling onto the heel from a height
Talus is driven into the calcaneus
What is meant by a comminuted fracture? Is a calcaneus fracture often a comminuted fracture?
Fracture where the bone breaks into several pieces
Yes
How does the calcaneus appear on X-ray when fractured?
Shorter and wider than normal
What complications can result from a calcaneus fracture, even after treatment?
There can be disruption of the subtalar joint - causing arthritis
Therefore pain upon inversion and eversion - particularly painful when walking on uneven ground
How are the metatarsals named?
Numbered I - V (medial to lateral)
What is the common structure of a metatarsal bone?
Distal head
Proximal base
Joined by a shaft
How many articulations does each metatarsal have?
3 or 4
Describe the articulations of metatarsals
Proximally - tarsometatarsal joints - either cuneiforms or cuboid bones
Laterally - intermetatarsal joints - adjacent metatarsals
Distally - metatarsophalangeal joint - proximal phalanx
What is the most common method of metatarsal fracture?
Direct blow to the foot - e.g. Heavy object dropping on the foot
What are two less common mechanisms of metatarsal fracture?
Stress fracture due to repeated stress to the bone
Excessive inversion of the foot
A stress fracture of the metatarsal is common in which group of people and which metatarsals?
Athletes
2,3 and 4
How can excessive inversion the foot result in metatarsal fracture?
The fiburalis brevis muscle can tear off the base of metatarsal V
How many phalanges do the toes have? How are they named?
All have 3, except the big toe which has 2
Proximal (Intermediate) Distal
What is the general structure of each phalanx?
Each phalanx consists of a body, a proximal extremity and a distal extremity of
