Lower Limb Flashcards
1
Q
Weight-bearing epiphyses are formed as a result of
A
weight bearing pressure
2
Q
Traction epiphyses are formed as a result of
A
attachments of ligaments and muscles that exert force
3
Q
The head of the femur is a ______ epiphysis
A
weight-bearing (fuses early 20s)
4
Q
The greater trochanter is a ______ epiphysis
A
traction
5
Q
The head of the femur is oriented
A
upwards, medially, and slightly anteriorly (ante-verted)
6
Q
T/F The anterior part of the head of the femur is within the socket
A
False, it lies anteriorly outside the socket, protected by the psoas bursa
7
Q
T/F The psoas bursa communicates with the acetabular joint
A
False, but it may
8
Q
The head of the femur articulates with
A
the roof of the acetabulum (thickest cartilage here)
9
Q
What are the intra-articular structures of the hip joint?
A
fat pad, labrum, ligamentum teres
10
Q
What is ligamentum teres?
A
Directs branch of obturator artery to femoral head in development until puberty
11
Q
What is the role of the vertical bundle of trabeculae?
A
Weight-bearing in stance
12
Q
What is the role of the arcuate bundle of trabeculae?
A
Resisting bending forces on the neck of the femur
13
Q
What is the significance of the 2 trabeculae system in the neck of the femur?
A
At the inferior aspect of the arcuate bundle where the 2 intersect becomes a site of weakness in ageing and osteoporosis due to loss of trabeculae
14
Q
At the hip joint, the line of gravity passes _________ the centre of the joint
A
behind
15
Q
At the knee joint, the line of gravity passes _________ the centre of the joint
A
in front of
16
Q
At the ankle joint, the line of gravity passes _________ the centre of the joint
A
in front of
17
Q
What is the ‘close packed position’?
A
Position of greatest stability; articular surfaces meet as best they can with the capsules and ligaments taught - hip extension, abduction, and medial rotation (open packed is sitting cross-legged, least stability)
18
Q
Which ligaments of the hip joint blend with the capsule?
A
Pubofemoral and ischiofemoral
19
Q
Iliofemoral ligament attaches
A
ASIS to intertrochanteric line
20
Q
What is the function of the iliofemoral ligament?
A
Tightens in extension to resist further extension; causes medial rotation in extension
21
Q
Retinacular fibres
A
extension of capsule around neck of femur; transmits retinacular blood vessels to epiphysis (growth) and head of femur (following closure)
22
Q
Disruption of retinacular blood vessels in development causes
A
Perthe’s disease - avascular necrosis of the femoral head
23
Q
What is a screw-home mechanism?
A
The joint gets tighter as it goes into extension - eg in hip, medial rotation occurs with extension to lock the joint
24
Q
_______ rotation occurs in stance, _______ rotation occurs in swing
A
medial; lateral
25
Main movements of the hip are in the ________ plane
sagittal
26
What is the function of gluteus maximus?
hip extension in extreme force/acceleration; stabilizes pelvis when rising from seated position
27
The principal role of the cuff muscles in the hip joint is to
pull the head of the femur into the socket; they can laterally rotate the hip as well
28
Range of flexion at the hip
120 deg
29
Range of extension at the hip
10-20 deg
30
Medial rotation of the hip is associated with
stance
31
Lateral rotation of the hip is associated with
swing
32
Gluteus medius and minimus _______ the thigh
abduct
33
Illiopsoas ________ the thigh
flexes
34
What is the critical role of gluteus medius and minimus?
Keeping the pelvis level in walking by pulling it down to prevent fall to the unsupported side
35
Injury to the gluteus medius and minimus results in
Trendellenberg gait where the pelvis is unstable and drops to the unsupported side
36
The hip joint is innervated by
articular branches of the femoral and obturator nerves
37
Referred pain from the hip via the obturator nerve presents
medial thigh above the knee
38
Referred pain from the lumbar spine and sacro-iliac joints presents
Hip joint
39
Hip flexion myotome
L2 L3
40
Hip extension myotome
L4 L5
41
Knee extension myotome
L3 L4
42
Knee flexion myotome
L5 S1
43
Dorsiflexion myotome
L4 L5
44
Plantar flexion myotome
S1 S2
45
Inversion myotome
L4
46
Eversion myotome
L5 S1
47
Hallicus flexion myotome
S1 S2
48
Hallicus extension myotome
L5 S1
49
Blood supply to the hip joint comes from
retinacular fibres from the medial and lateral femoral circumflex arteries (profunda femoris; femoral a.)
50
Which vessels are susceptible in a #NOF?
retinacular and circumflex vessels
51
Posterior dislocation of the femur endangers
Sciatic nerve
52
What is the normal neck-shaft angle of the femur?
135 deg (smaller in women)
53
Coxa valga
neck-to-shaft angle less than 125
54
Coxa vara
neck-to-shaft angle greater than 125
55
Why does a #NOF present with external rotation and shortening of the limb?
Spasm of gluteal muscles, especially external rotators
56
Pain of osteoarthritis in the hip joint commonly refers via
articular branches of the obturator nerve tf presenting on medial knee
57
How is congenital hip dislocation tested?
Abdudction of the flexed hip joint
58
How is congenital hip dislocation treated?
Hips braced in abducted position so that adductor magnus will pull along the line of the femur and the head of the femur back into the socket
59
What are the two types of hip dislocation?
Traumatic and congenital
60
Rotation of the knee only occurs during
flexion
61
The knee is in closed-pacjed position when in __________
extension
62
Bursae in the knee joint sit
between the patella and the overlying ligament; between the femur and the quadriceps tendon; deep to popliteus and semimembranosus; between ligaments and bone
63
The knee gets its support primarily from
cruciates, collaterals, menisci, and muscles
64
The knee joint is most vulnerable in
flexion and rotation
65
Medial condyles of tibia and femur are
longer and thinner than the lateral
66
The femur rotates ______ on the tibia in moving from flexion to extension
medially
67
What is the screw-home mechanism at the knee?
passive, occurs around the tightening ACL in the last 15-20deg of extension - the femur rotates medially on the tibia
68
________ is responsible for initiating flexion at the knee
Popliteus
69
Locking of the knee in extension is ________ whereas flexion of the knee is ________
passive; active
70
Menisci are made of
fibrocartilage
71
T/F Menisci are covered in synovial membrane
False; this would wear out and cause swelling
72
Menisci are lubricated by
synovial fluid
73
The synovial membrane covers
interior of the joint capsule and cruciates (anterior of PCL and ACL)
74
The cruciate ligaments are _____capsular but ______synovial
intracapsular but extra-synovial (outside the membrane)
75
Why is an ACL tear likely to be accompanied by bleeding?
because the cruciates are covered in synovial membrane which is very vascular
76
What is Osgood-Schlatter disease?
apophysitis of tibial tubercle - inflammation of the patellar ligament at the tibial tuberosity
77
The knee joint capsule is reinforced anteriorly by
patellar tendon and retinacular fibres (lateral and medial)
78
The knee joint capsule is reinforced laterally by
popliteus, biceps femoris, IT band
79
The knee joint capsule is reinforced medially by
pes anserinus tendons
80
The knee joint capsule is reinforced posteriorly by
oblique popliteal ligament from semimembranosus
81
What are the components of pes anserinus?
Say Grace Before Tea: Sartorius, Gracilis, Bursa, semiTendinosus
82
Which bursa communicate with the knee joint?
suprapatellar and those deep to popliteus and semimembranosus
83
What is a Baker's cyst?
Thickening of the lining of the bursa at the back of the knee, becomes irritated in flexion
84
The anterior cruciate ligament travels __________ from the ___________ to the __________
Posterolaterally, anterior tibia to lateral condyle
85
The posterior cruciate ligament travels __________ from the _________ to the __________
anteromedially, posterior tibia to medial condyle
86
What is the function of the ACL?
Stops anterior displacement of the tibia on the femur/posterior displacement of the femur on the tibia
87
What is the function of the PCL?
Stops anterior displacement of the femur on the tibia/posterior displacement of the tibia on the femur in flexion eg going down stairs
88
The ACL is ________ in flexion and ________ in extension
twisted; untwisted & tight (pulls femur medially to lock it)
89
ACL is commonly injured when
rotation occurs in the opposite direction (laterally) on the weight bearing leg - ie moving laterally in extension instead of medially
90
ACL repair grafts are commonly taken from
mid-portion of patellar tendon or a hamstring tendon from the pes anserinus (sartorius)
91
PCL is prone to injury in
falls on flexed knee; bumper bar impact on femur
92
The MCL attaches to
medial femoral epidondyle to medial tibia close to pes; deep part blends w/capsule and inserts into medial meniscus
93
What is the function of the MCL?
Resists valgus (abduction) forces and lateral rotation of the tibia; limit anterior displacement of tibia 2nd to ACL
94
The LCL attaches to
Lateral epidcondyle to head of fibula; separated from meniscus but popliteus tendon
95
What is the function of the LCL?
Resists varus (adduction) forces, medial movement of tibia
96
What is the 'unhappy triad'?
Tearing of the ACL, MCL, and medial meniscus usually due to lateral rotation of the femur on the planted tibia
97
What is the function of the menisci?
Absorb and distribute weight; increase area of contact by 1/3
98
Menisci move with the femur during ________ but the tibia during ________ and _______
rotation; flexion and extension
99
Menisci are endangered in
changing direction with the knee flexed
100
Locked knee occurs when
a flap of torn cartilage gets in the way of the articular surfaces and prevents unlocking
101
The meniscus receives blood supply to the
(because it is fibrocartilage it can have a blood supply) periphery but not the medial zone which is avascular (white)
102
What structures are responsible for stability at the patellofemoral joint?
raised lateral lip of femoral condyle (passive); medial patellar retinaculum/capsule (passive); strong vastus medialis (active)
103
What is the role of vastus medialis in stabilizing the patella?
Pulls patella in position during the last 15-20 degrees of extension
104
The Q angle is between
quadriceps tendon and patellar tendon
105
What is chondromalacia patellae?
inflammation of the underside of the patella and softening of the cartilage
106
Why is fibular fracture common with tibial fracture?
the 2 bones form a ring (ring hypothesis)
107
The tibial tuberosity is a _________ epiphysis
Traction
108
The ___________ eminence sits between the tibial plateaus and serves as attachment for
intercondylar eminence; cruciate and meniscal hook ligaments
109
Fractures in the distal 3rd of the tibia heal more slowly due to
less blood supply than proximal
110
The soleal line runs
obliquely along the posterior tibia (lateral to medial)
111
The superior tibiofibular joint is a ______________ joint and allows _________ movement
plane synovial; some gliding movement
112
The superior tibiofibular joint is supported by
LCL, ant and post tibiofibular ligaments, biceps femoris tendon
113
The inferior tibiofibular joint is a ___________ joint and
fibrous (syndesmosis)
114
The inferior tibiofibular joint functions to
prevent separation of tib and fib in weight bearing
115
The inferior tibiofibular joint is reinforced by
ant and post tibiofibular ligaments, continuous fibres of IOM
116
What is the malleolar mortise?
formed by lateral malleolus, hinge of ankle joint that connects tib and fib to the talus
117
What is a March Fracture?
Stress fracture of the 2nd metatarsal due to it's wedged position between the 1st and 3rd metatarsal bones
118
What are accessory bones?
Secondary centres of ossification that don't fuse with the parent bone
119
Talocrural joint
Between talus and mortice between tib and fib malleoli
120
The taolcrural joint is reinforced by which ligament?
Inferior transverse ligament
121
The talocrural joint is a ____________ joint and permits ____________ and __________ only
synovial hinge; flexion and extension
122
What is the significance of the longer lateral malleolus?
Creates an oblique axis of rotation such that dorsiflexion is associated with eversion and plantar flexion is associated with some inversion - it's not a straight hinge
123
Subtalar joint
talocalcaneal joint
124
Midtarsal joints
talocalcaneonavicular and calcaneocuboid
125
The ankle is more stable in ___________ due to
dorsiflexion; the talus is wider anteriorly and fits better into the mortice in dorsiflexion; hence the ankle is less stable in plantar flexion where the narrower posterior talus sits in the mortice
126
Deltoid ligament
MCL of ankle joint
127
Spring ligament
plantar calcaneonavicular ligament
128
Deltoid ligament/MCL has ___ parts
4
129
LCL at the ankle has ___ parts
3
130
_____% of ankle sprains are ________ injuries
85-90%; inversion
131
The ankle is most vulnerable to injury in
inversion and plantarflexion
132
Inversion injuries to the ankle stress
LCLs and fibularis muscles
133
Pott's fractures are
associated with ankle inversion sprains - fracture of the medial malleolus and fibular shaft
134
Inversion injuries of the ankle commonly fracture
lateral malleolus of fibula
135
Inversion and eversion occur about the ________ joints
subtalar/talocalcaneal and taleocalcaneonavicular (TCN)
136
What is the function of the spring ligament?
Supports the head of the talus inferiorly into the TCN joint
137
What is the significance of the sinus tarsi?
carries the interosseus talocalcaneal ligament which binds the talus and calcaneus together, and the vascular sling which supplies the otherwise avascular talus
138
Where is the sinus tarsi?
between the talus and calcaneus, between the talocalcaneal articular surfaces
139
Fracture of the talus occurs at the _______ and endangers __________
neck; vascular sling - can get avascular necrosis of talus
140
Heel strike in running is in which plane?
eversion
141
Weight transfer to the forefoot in running puts the foot into
inversion (greater ROM)
142
The calcaneocuboid joint is a ___________ joint and allows ____________
plane synovial joint; rotary gliding movement for pronation and supination
143
What occurs in pronation of the foot?
eversion at subtalar and TCN, lateral rotation at calcaneocuboid
144
What occurs in supination of the foot?
inversion at subtalar and TCN, medial rotation at calcaneocuboid
145
What joints form the midtarsal joint?
TCN and calcaneocuboid
146
T/F The calcaneocuboid joint is involved in inversion and eversion with the TCN
False; it provides some rotation but is functionally independent of the TCN
147
Pronation and supination of the foot occur about the ___________ joint
calcaneocuboid (with subtalar and TCN involvement)
148
Pronation and supination of the foot refers to relative movement between
hindfoot (stable) and forefoot around it - up and down movement of the arch
149
What are the arches of the foot?
2 longitudinal: medial (higher) and lateral, 1 transverse hemi-arch
150
Arches of the foot are supported by which ligaments?
Long and short plantar ligaments, plantar aponeurosis
