Anatomy lecture 13: Hip and knee joints (pelvic gircle joints & foot muscles) Flashcards
Femoral head:
Forms 2/3 of a sphere of diameter 4-5cm.
Supported by the neck of femur
Axis runs:
-superiorly
-medially
-anteriorly
Angle of inclination:
head of the femur in adult:
125
Fovea:
impression on the head of the femur for the attachment of the round head.
Angle of anteverison:
head of the femur forms an acute angle of 10-30 degrees with femoral plane
Femoral anteversion:
determined by measuring the angle formed between the long ais of the femoral neck and line parallel to the dorsal aspect of the femoral condyles.
Anteversion:
Increase in angle: causes in-toeing, pigeon toes, as well as genu valgum
Retroversion:
Decrease in angle: out-toeing (external rotation) during standing and walking as well as genu valgum during standing
Acetabulum:
hemispherical and is bounded at the acetabular rim.
lunate surface of acetabulum: lined by horseshoe-shaped articular cartilage, interrupted inferiorly by the acetabular notch
Directed laterally, inferiorly, and anteriorly
Acetabular fossa:
permits movement of the ligamentum teres & importantly serves as a reservoir for synovial fluid when hip is heavily loaded.
When joint surfaces are decreased, synovial fluid returns to the joint space for lubrication and nutrition to the articular cartilages.
Acetabular labrum:
fibrocartilaginous ring at the acetabular rim
Transverse acetabular ligament (TAL):
attached to either side of the acetabular notch & labrum
Ligamentum teres (LT):
flattened fibrous band:
O: acetabular notch
(runs the floor of the acetabular fossa)
I: fovea femoris capitis
-embedded in fibro-adipose tissue
-lined w/ synovial membrane
-Extremely strong
Primary function: carry the vascular supply to the head of the femur
Iliofemoral ligament:
Y-shaped ligament w/ two thick borders (superior & inferior bands)
Covers hip anteriorly & superiorly
Pubofemoral ligament:
-anterior & inferior to hip
-limiting lateral rotation & abduction
Ishiofemoral ligament:
posterior & inferior, limiting rotation
Fibrous layer of the joint capsule:
-extension of the hip joint winds (increases the obliquity) pulling the femur tightly into the acetabulum, increasing stability of joint
-Flexion unwinds the fibers of the capsule
Active hip flexion w/ knee flexed:
70-120 by hamstrings
Active hip flexion w/ knee extended:
70-90 by hamstrings
Hyper extension of the hip:
Is limited to 10-20 by iliofemoral ligament .
when knee is flexed it is less because there is a loss of movement at the knee.
Hip abduction:
45 degrees and usually accompanied by the elevation of the pelvis
Hip adduction:
contact between the two thighs or 0 degrees
legs crossed: 30-40 degrees
Medial rotation of hip:
30 degrees
Lateral rotation of hip:
60 degrees
Flexor muscles of the hip:
1) Psoas major
2) Iliacus
3) Sartorius
4) Rectus femoris
5) Tensor fascia Latae
6) Pectineus
7) Adductor longus
8) Gracilis
9) Anterior fibers of glutei Medius & minimus
First group produces flexion, abduction, and med. rot. (9, 5)
Second group produces flexion, adduction, and lat. rot. (1,2,6,7)
First group of extensor muscles of the hip:
1) gluteus maximus
2) posterior fibers of gluteus Medius
3) posterior fibers of gluteus minimus
(all inserted into femur)
Second group of the extensor muscles of the hip:
4) biceps femoris
5) semitendinosus
6) semimembranosus
7) adductor magnus
(inserts at the vicinity of the knee joint)
Abductor muscles of the hip:
1) anterior fibers of the gluteus medius
2) Gluteus minimus
3) Tensor fascia Latae
4) Gluteus maximus (upper fibers)
5) piriformis
In certain positions other muscles can contribute to the fore of abduction:
-Sartorius
-Obturators
-Gemelli
Adductor muscles of the hip:
1) adductor magnus
2) Gracilis
3) Semimembranosus
4) Semitendinosus
5) Biceps femoris
6) gluteus maximus
7) quadratus femoris
8) Pectineus
9) Obturator externus
10) Adductor longus
11) Adductor brevis
Lateral Rotator muscles of the hip:
1) piriformis
2) Obturator internus
3) Obturator externus
4) Quadratus femoris
5) Gluteus maximus
6) Gluteus Medius
7) Gemelli
Medial rotator muscles of the hip:
1) tensor fascia Latae
2) gluteus minimus (anterior fibers)
3) gluteus Medius (anterior fibers)
Knee joint:
synovial hinge joint
2 DOF
three articular surfaces
-Medial tibio-femoral
-lateral tibio-femoral
-patello-femoral
Functions of the knee:
-withstanding large forces
-providing great stability
-enabling a large ROM
(many sport injuries are preventable through appropriate conditioning and training)
Articular surfaces of the knee joint:
Condyles form the lips of the pully and extend anteriorly by the pully-shaped patellar surfaces.
blunt eminance runing through the center if the superior part of the tibia which acts as a pivot when articulating with the intercondylar notch
Retinacula & ligaments:
reinforce and become integral parts of the capsule.
Proximal tendon of the popliteus:
pierces capsule & attaches to the lateral femoral condyle
Oblique popliteal ligament:
semimembranosus reforms part of this ligament and give off fibers to the MCL.
reinforces the capsule posteriorly.
Arcuate popliteal ligament:
strengthens the joint capsule posterio-laterally.
passes over the popliteus tendon
spreads over the posterior portion of the knee joint.
Collateral ligaments of the knee:
Strengthen the articular capsule on its medial and lateral aspects.
Responsible for transverse stability of the knee during extension.
stretched during extension & slackened during flexion
Medial (tibial) collateral ligament:
O: medial epicondyle of femur
I: upper end of tibia posterior to pes anserine
(runs inferiorly and laterally)
Lateral (fibular) ligament:
O: lateral epicondyle of the femur
I: head of the fibula
Anterior cruciate ligament:
weaker cruciate ligament:
O: anterior intercondylar area of the tibia
I: internal aspect of the lateral condyle of femur
Posterior cruciate ligament:
O: posterior intercondylar area of tibia
I: lateral surface of the medial femoral condyle
Cruciate ligaments are intracapsular but ______________
extra synovial
Menisci:
(semi-lunar fibrocartilages) corrected the lack of congruency in the articular surfaces.
Crescent shaped w/ anterior and posterior horn.
Lateral meniscus come closer so its almost a complete circle.
Medial meniscus is C-shaped
Each horn anchored by the tibial condyle in anterior and posterior intercondylar areas
Important ligament attachments of the menisci:
1) two anterior horns: the transverse ligament of the knee
2) medial collateral ligament
3) lateral collateral of the ligament, separated from its corresponding meniscus by the tendon of popliteus
Movements of the knee joint:
DOF: flexion-extension, & axial rotation
Flexion: 120-150
Hyperextension minimal and will not exceed 15.
axial rotation: occurs in transverse plane when knee is flexed to 90.
Automatic axial rotation called screw-home mechanism:
inevitably and involuntarily linked to movements of flexion and extension.
End of extension or the start of flexion.
Extension=external rotation
Flexion= internal rotation
The patella which is embedded in the tendon of this muscle increases the efficiency of the muscle up to ____.
33%
Flexor muscles of the knee are the hamstrings and a few other muscles consisting of:
1) Biceps femoris
2) semitendinosus
3) semimembranosus
4) Gracilis
5) Sartorius
6) Gastrocnemius
Quadriceps are the extensor muscles of the knee:
1) Vastus intermedius
2) Vastuc lateralis
3) Vastus medialis
4) Rectus femoris
Pelvic region:
Hip joints are the most structurally stable, yet mobile, joints in the body.
Transmits large forces between the trunk and the ground.
Sustains more than three times the body weight with each step.
Rotator muscles of the knee:
Sacroiliac joint:
Can be a sight for low back pain often following childbirth due to injuries of ligaments, hyper-and hypo-mobility, or inflammatory conditions
Synovial planar (gliding): made between auricular surfaces of the ilium part of the hip bone and sacrum.
sacral surfaces are covered in hyaline cartilage and the iliac surface is covered in fibrocartilage.
Interosseous ligaments:
fill the space between the sacrum and the inner side of the iliac tuberosity.
Posterior sacroiliac ligaments:
cover the interosseous ligaments and the posterior aspect of the sacrum.
Anterior sacroiliac ligaments:
anterior aspect of the sacroiliac joint
Sacrotuberous and sacrospinous ligaments:
connecting to the SPs and ischial tuberosity, providing them leverage to hold the distal aspect of the sacrum against the anterior weight-bearing forces.
Self-locking mechanism:
the fibers of the interosseous and posterior sacro-iliac ligaments run obliquely, the axial wight pulls the sacrum together compressing the sacrum between the ligaments.
this locks the irregular but congruent surfaces of the sacroiliac joints together.
iliolumbar ligaments are accessory ligaments to this.
Sacrococcygeal joint:
synovial planar joint or a symphysis synarthrosis joint depending on the age of the person.
Intercoccygeal joints:
synarthrosis joints
motion increases between these joints during pregnancy, and ossification of the joints occurs w/ aging.
Pubic symphysis:
articulating surfaces of the pubic bones are separated by the fibrocartilaginous interpubic disc.
Small motions occur at these joints
completes the closure of the ring of the pelvis
Extensor digitorum brevis:
O: dorsal surface of calcaneus
I: lateral side of the tendon of extensor digitorum longus for toes #2-4
A: Ext. of toes 2-4 @ MTP & PIP Joints
N: Deep fibular N. (peroneal)
Extensor hallucis brevis:
O: dorsal surface of calcaneus
I: proximal phalanx of big toe.
A: Extension of big toe @ MTP joint
N: Deep fibular N (peroneal)
1st layer of the sole of the foot:
1) abductor hallucis
2) flexor digitorum brevis
3) abductor digiti minimi
2nd layer of the sole of the foot:
1) Flexor hallucis longus tendon
2) flexor digitorum longus tendon
3) quadratus plantae (flexor accessorius) lumbricals
4) Lumbricals (4 muscles)
3rd layer of the sole of the foot:
1) flexor hallucis brevis
2) adductor hallucis
3) flexor digiti minimi brevis pedis
4th layer of the sole of the foot:
1) plantar interossei (3muscles)
2) dorsal interossei (4 muscles)
Abductor hallucis:
O:
-medial process of tuberosity of the calcaneus
-Plantar fascia
I: Base of the proximal phalanx of the big toe
A: Abd. of big toe @ MTP Joint
N: Medial plantar N.
Flexor digitorum brevis:
O:
-medial process of tuberosity of the calcaneus
-plantar fascia
I: sides of the middle phalanx of toe #2-5
A: Flex. of toes 2-5 @ MTP & PIP joints
N: Medial Plantar N.
Abductor digiti minimi:
O:
-Lateral process of tuberosity of the calcaneus
-Plantar fascia
I: base of the proximal phalanx of 5th toe
A: Abd. of toe 5 @ MTP Joint
N: Lateral plantar N.
Quadratus plantae:
O: calcaneus
I: tendon of the flexor digitorum longus
A: Assists flexor digitorum longus to flex toes 2-5 @ MTP and IP Joints
N: Lateral plantar nerve
Lumbricals
O: Tendon of the flexor digitorum longus
I: dorsal digital expansion of toes #2-5
A:
1) Flex of toes 2-5 @ MTP Joints
2) Ext. of toes 2-5 @ PIP & DIP Joints
N:
Lumbrical 1 => Medial Plantar N.
Lumbrical 2-4 => lateral plantar N.
Flexor hallucis brevis:
O:
-cuboid
-3rd lateral cuneiform
I: medial and lateral sides of the proximal phalanx of great toe (tendon contains sesamoid bones)
A: Flex of big toe @ MTP Joint
N: Medial Plantar N.
Flexor digiti minimi brevis:
O:
-base of 5th metatarsal
-tendon of fibularis longus
I: proximal phalanx of 5th toe
A: Flex. of 5th toe @ MTP Joint
N: Lateral plantar N.
Adductor hallucis:
O:
Oblique head:
-The base of metatarsals 2-4
-Tendon of fibularis longus
Transverse head:
-Plantar metatarsophalangeal ligaments
I: base of the proximal phalanx of great toe
A: Add. of big toe @ MTP Joint.
N: Lateral plantar N.
Dorsal interossei:
O: adjacent sides of metatarsal bones
I: base of proximal phalanges & dorsal digital expansion
1st inserted to the 2nd
the others are inserted to the lateral sides of 2nd, 3rd, and 4th toes
A:
1) Abd. toes 2-4 @ MTP
2) Flex. toes 2-4 @ MTP
3) Ext. toes 2-4 @ IP
N: Lateral Plantar N.
Plantar interossei:
O: metatarsal bones 3-5
I: base of proximal phalanges & dorsal digital expansion
1st inserted to medial side of the 3rd toe, and the other two are inserted into the medial sides of the 4th and 5th toes.
A:
1) Add. toes 3-5 @ MTP
2) Flex. toes 3-5 @ MTP
3) Ext. toes 3-5 @ IP
N: Lateral Plantar N.
