Joints of Lower Limbs Flashcards
1
Q
Hip joint is a type of
- function
- movement limited
- more stable than?
A
- Multiaxial ball (femoral head) and socket (acetabulum) type
- synovial joint
- can support body weight without muscular exertion
- movement is more limited than shoulder (glenohumeral) joint
- hip joint is also more stable than glenohumeral joint
2
Q
Acetabulum has 3 parts
A
- socket to head of femur
- lunate surface
- acetabular notch
3
Q
What is an acetabular labrum
Transverse acetabular ligament function
A
Acetabular labrum
- fibrocartilage rim that deepens the socket
- retains femoral head in the socket even if ligaments & muscles are severed
2. Transverse acetabular ligament - bridges the acetabular notch helps hold femoral head in place
4
Q
Hip joint capsule
- encloses what
- location anterior/posterior
A
- joints capsule encloses the head and neck of femur
- anteriorly extends to intertrochanteric line
- posteriorly extends to distal part of neck
5
Q
Iliofemoral ligament -nickname -function -characteristic Pubofemoral ligament function Ischiofemoral ligament fucntion
A
Iliofemoral ligament -Y ligament of Bigelow -limits hyperextension -strongest ligament of body Pubofemoral ligament -limits abduction ischiofemoral ligament -limit hyperextension
6
Q
Mechanics of hip joint
- hip flexes
- hip extends and hyperextends
- hip components pulled together
A
- As hip flexes, the ligaments untwist, become more relaxed. hip joint is less stable
- As hip extends and hyperextends, ligaments twist become tighter. Hip joint components pulled together tighter more stable
7
Q
Knee joint
- characteristics
- type of joint
- location
- encompassed
A
- largest joint in the body
- hinge type synovial joint which allows flexion and extension. Some rotation in flexed position
- btw 2 condyles of femur & tibia; btw patella & femur
- encompassed by fibrous capsule & synovial membrane
8
Q
Ligaments of Knee Joint 3
A
- patellar ligament
- lateral (fibular) collateral ligament
- Medial (tibial) collateral ligament
9
Q
rupture of fibular collateral ligament
rupture of tibial collateral ligament
A
- fibular collateral ligament- uncommon; complete rupture may however avulse head of fibula or stretch common fibular n. causing foot drop
- tibial collateral ligament- associated with tearing of medial meniscus of ACL, common in football injury; look out for damage to 3 C’s (collateral ligaments, Cruciate ligaments, Cartilages (menesci)
10
Q
Fibrous capsule of the knee joint
A
- oblique popliteal ligament
- arcuate popliteal ligament
11
Q
Intra-articular of knee joints (4)
A
- anterior cruciate ligament
- posterior cruciate ligament
- medial meniscus
- lateral meniscus
12
Q
Function and characteristics
- Anterior cruciate ligament
- Posterior cruciate ligament
- Medial meniscus
- lateral meniscus
A
- Anterior cruciate ligament- prevents posterior displacement of femur on the tibia and hyperextension of knee joint; it is weak, sometimes torn with tibial collateral ligament and medial meniscus
- Posterior cruciate ligament- stronger; prevent anterior displacement of femur on the tibia and hyperflexion of knee joint
- Medial meniscus- C-shaped; lateral border attached to tibial collateral ligament
- lateral meniscus- posterior meniscofemoral ligament
13
Q
Functions of knee joint ligaments
- cruciate
- collateral ligaments
A
cruciate
-prevent anterior & posterior movement of knee joint
-anterior: taut when knee extended; when knee flexes, femoral attachment of ACL moves anteriorly; ACL relaxes in flexion
-posterior: taut when knee flexed; when knee extends, femoral attachment of PCL moves posteriorly; PCL relaxes in extension
collateral ligaments
-prevent side to side movement
-become taut when knee fully extended
14
Q
Attachment of medial & lateral meniscus
General descriptions of menisci
A
- medial meniscus attached to medial collateral ligament & intercondylar eminence
- lateral meniscus attached to intercondylar eminence & posterior meniscofemoral ligament
- menisci deepen the cup formed by tibial condyles
- menisci penetrated by nerves but almost no blood vessels
- when menisci are torn, pain but no bleeding
- torn meniscus does not heal
15
Q
The menisci formed what and by what?
penetrated by? but no?
when torn, what is present or missing?
A
- menisci deepen the cup formed by tibial condyles
- menisci penetrated by nerves, but almost no blood vessels
- when torn, pain but no bleeding
- torn meniscus does not heal
16
Q
Knee joint most stable when extended because?
- femur & tibia?
- structure
- movement
A
- femur & tibia fit together best in this position
- joint structures are close packed
- tibia (or femur) is rotated to maximize congruence (medial side of tibia rotated anteriorly)
17
Q
What are bursae of the knee joint?
A
- fluid filled sacs to protect the tendons
- one continuous sac but there are 12 named parts
- suprapatellar bursa (or pouch) under the patella
18
Q
Joints of Leg
Tibiofibular J
A
Tibiofibular joint
- proximal (plane synovial joint)
- distal (fibrous joint)
- tibia & fibula are also held together by interosseous membrane
19
Q
Joints of Leg
Ankle J
A
Ankle Joint
- hinged-type, synovial joint
- articulations btw tibia/fibula & talus
- dorsiflexion & plantarflexion
20
Q
- what part of talus trochlea is wider
- when dorsiflexed, which part of trochlea push what
- ankle joint is strongest/weakest in
A
- anterior trochlea wider than posterior trochlea
- when foot dorsiflexed, wide anterior part of trochlea pushed apart distal tibiofibular joint
- ankle joint strongest in dorsiflexion and weakest in plantarflexion
21
Q
Why is the dorsiflexion in ankle joint the strongest? (4)
A
- the trochlea fills the articular space completely
- malleoli grip the talus tighly because anterior part of talus is wider
- grip is further tighten by interosseous ligament and the anterior & posterior tiobiofibular ligaments
- several tendons & ligaments cross over the joint tightly bound down by the deep fascia
- unstable in plantarflexion but can be strengthened by training.
22
Q
Components of lateral collateral ligament of ankle (3) limit?
Components of medial (deltoid) ligament (4) limit?
-which one is stronger? what does it prevents?
-fibrous capsule does?
A
1. lateral collateral ligament of ankle (limit eversion) -posterior talofibular l -calcaneofibular l -anterior talofibular l 2. Medial (deltoid) ligament (limit inversion) -posterior tibiotalar part -tibiocalcaneal part -tibionavicular part -anterior tibiotalar part 3. Deltoid ligament is stronger than lateral ligament. Prevents medial dislocation of ankle joint 4. the fibrous capsule is strengthened by the Deltoid ligament & lateral ligament
23
Q
- which joint most commonly injured?
- which side?
- what happen in a sprained ankle
A
- ankle joint
- lateral ligament is weaker, more likely to injured
- sprained= twisting of ankle and nearly always an inversion injury
- unless foot held in eversion, fracture dislocation of ankle may occur if ankle is severely inverted again.
24
Q
Joints of Foot: Subtalar/talocalcaneal Joint
- type of joint
- movement
- eversion/inversion which is more common injured
A
- gliding type of synovial joint
- considered as combined with talocalcaneal part of talocalcaneonavicular joint
- movements: inversion, eversion, adduction (supination), abduction (pronation), plantarflexion, dorsiflexion
- inversion injuries more common
25
Q
Joints of Foot: Transverse tarsal (2)
-movement
A
- Transverse tarsal:
1. talonavicular
2. calcaneocuboid - inverson & eversion
26
Q
which 4 joints of foot cause flexion & extension
A
- tarsometatarsal
- metatarsophalangeal
- proximal interphalangeal
- distal interphalangeal
27
Q
tarsometatarsal joints
- type
- movement
- description
A
- plane type synovial joint= gliding or sliding
- 3 separate joint cavities
- first joint has max movmeent, 1st metatarsal & medial cuneiform bone
- second strongest is all 3 cuneiform bones and 2nd 3rd metatarsals. Vulnerable stress/march fractures
- third involve cuboid bone and 4th 5th metatarsals
28
Q
metatarsophalangeal
- type
- movement
- description
A
- condyloid synovial joint
- flexion, extension, abduction, adduction
- 1st metatarso-phalangeal joint is largest owing to size of head of first metatarsal bone and the presence of sesamoid bone in the two tendons of flexor hallucis brevis.
29
Q
Function of arch
- 2 arches
- how are arches maintained?
A
- arch of foot supports compressive stress, shock absorbers
- arches maintained by:
1. shapes of interlocking bones
2. strength of ligaments & plantar aponeurosis
3. action of muscles - longitudinal arch= medial & lateral; medial more important
- transverse arch
- body weight divided about equally btw calcaneous and head of metatarsal bones
- plantar ligaments & plantar aponeurosis important in maintaining these arches
30
Q
Ligaments of the foot (6)
A
- plantar aponeurosis
- long plantar ligament,
- provides main support for lateral longitudinal arch
2a. short plantar ligament
- aids in both spring and long ligaments - plantar calcaneonavicular ligament (spring)
- most important, provides resilience to medial longitudinal arch - flexor digitorum longus
- flexor hallucis longus
- fibularis longus
