Anatomy - ALL Flashcards
What is the pelvis and what does it do?
-Bony ring formed by the articulation of the left and right innominate (hip) bones and the sacrum
-Takes the weight of the body and transmits it to the lower limbs
What bones make up the hip bone and where do they join?
-Pubic, ilium and ischium bones
-Join at acetabulum
What do the hip bones articulate with anteriorly and posteriorly?
-Anteriorly - each other at the pubic symphysis
-Posteriorly - sacrum at sacroiliac joints
What is this?
Describe it in life:
-Obturator foramen
-Almost completely covered over by obturator membrane and muscles attached to it
-Small gap in membrane and muscle (obturator canal) allows vessels to pass between pelvis and thigh
What do they surround?
Obturator foramen
What are these?
Iliac crests - uppermost parts of the ileum
Ischial tuberosity
What does the red articulate with?
Acetabulum of the pelvis
Describe it:
-Linea aspera
-Bony verticle ridge on the posterior aspect of shaft
-Muscle attachment
-Patella
-Lies anterior to the knee joint
What do the lateral and medial femoral condyles articulate with?
Proximal tibia at the knee joint
What movements are possible at the hip joint?
-Flexion
-Extension
-Abduction
-Adduction
-Medial (internal) and lateral (external) rotation
-Circumduction
What general groups of muscles allow what movements at the hip joint?
Anterior thigh - flexion
Medial thigh - adduction
Posterior thigh - extension
What movements are possible at the knee joint?
-Flexion
-Extension
Where does the thigh anatomically lie?
Inbetween the jip and knee
Name and describe it:
-Fascia lata
-Surrounds the thigh like a sleeve
Label and describe:
-Ileotibial band (or tract)
-Thickening of the lateral part of the fascia late
-Attaches to lateral aspect of proximal tibia and is important for stabilising the knee joint
What seperates the compartments of the thigh?
-Intermuscular septa
-Extend from fascia lata to the linea aspera
-Separate thigh into anterior, medial and posterior components
Describe the muscles of the anterior component of the thigh:
-7 muscles
As a group they:
-Primarly act as extensors of the knee but some act on hip joint
-Innervated by the femoral nerve (L2-L4)
What nerve is this and what spinal segments is it from?
-Femoral nerve
-L2-L4
What are the muscles of the anterior thigh?
-Quadriceps femoris (4 large muscles)
-Sartorius
-Iliopsoas
-Pectineus
What is common?
All muscles of the anterior thigh
What are these?
What muscles make up the quadriceps femoris?
-Rectus femoris
-Vastus lateralis
-Vastus medialis
-Vastus intermedius
What are the functions of the quadriceps femoris muscles?
-Prime extensor of the knee
-Form the bulk of the anterior thigh
Where do the quadriceps femoris muscles converge?
-Converge onto quadriceps tendon which runs over the patella
-Inerts onto the tibial tuberosity via the patella ligament
Tibial tuberosity
Describe rectus femoris:
-Lies in the midline of anterior thigh
-Attached to ASIIS proximally
-Crosses hip so contributes to flexion
Describe vastus lateralis:
-Lateral to rectus femoris
-Attaches to linea aspera on posterior aspect of the femoral shaft
Describe vastus medialis:
-Lies medial to rectus femoris
-Attaches to the linea aspera
Describe vastus intermedius:
-Lies deep to rectus femoris
-Attaches to anterior aspect of femoral shaft
What is the attachment and action of sartorius?
-Attached proximally to ASIS and inserts on medial aspect of proximal tibia
-Crosses hip and knee joints
-Flexes and laterally rotates the hip joint and can flex knee joint
-NOT prime mover - contributes
Describe iliopsoas:
-Lies proximally in anterior thigh
-Psoas major and ilacus converge via common tendon onto lesser trochanter of femur
-Prime flexor of the hip joint
ileopsoas
Describe pectineus:
-Proximal anterior thigh, medial to iliopsoas
-Attaches proximally at superior pubic ramus and distally on femur just inferior to lesser trochanter
-Flexes and adducts hip joint
Pectineus
Describe the muscles of the medial thigh:
-Contains 5 muscles
-As a group they:
-Primarily act as adductors of the hip
-Innervated by the obturator nerve (Spinal segments L2-L4)
What nerve is this and what spinal segments does it arise?
Obturator (L2-L4)
What are the muscles of the medial thigh?
-Adductor brevis
-Adductor longus
-Adductor magnus
-Gracilis
-Obturator externus
Describe adductor brevis and adductor longus:
-Similar points of attachment to the pubic bone and linea aspera
-Adductor brevis lies deep to longus
-Obturator nerve lies between them
Where does the obturator nerve lie in the medial thigh?
In between the adductor brevis and adductor longus
Describe the adductor magnus muscle:
-Large muscle that has an adductor part and a hamstring part
-Function differently and have different nerve supplies
Describe the adductor part of the adductor Magnus:
-Attaches to inferior pubic ramus and linea aspera
-Acts as an adductor
-Innervated by the obturator nerve
Describe the hamstring part of the adductor magnus:
-Attaches to ischial tuberosity and the adductor tubercle
What is the adductor hiatus?
-Gap formed between the distal attachments of the two parts of the adductor magnum
-Femoral artery and vein pass through this to reach the posterior thigh
Describe gracilis:
-Most medial muscle
-Attaches to the pubic bone and the medial aspect of the tibia
-Weak adductor and flexor of the hip and weak flexor of the knee
NOT a prime mover
Describe obturator externus:
-Attached to external surface of the obturator membrane and inserts on the femur near the greater trochanter
-Stabilises and laterally rotates hip joint
Describe the continuation of the external iliac artery:
-Femoral artery is continuation of external iliac
-Travels deep to inguinal ligament to enter proximal anterior thigh
-Lies relatively superficially
What is the vessel in red?
Femoral artery
Describe the pathway of the femoral artery in the thigh:
-Gives off large branch called profunda femoris (deep artery of thigh) which travels deep into thigh and supplies it
-Continues distally, traverses adductor hiatus and enters distal part of posterior thigh (popliteal fossa) to become popliteal artery
Label and describe its pathway:
-Obturator artery - branch of internal iliac artery
-Travels through obturator canal into medial component of thigh
-Anastomoses with branches from the femoral artery
Describe the veins exiting the pelvis into the thigh:
-Femoral - follows artery, lies medial to it in proximal thigh. Travels under inguinal ligament and is continuous with external iliac vein
-Obturator - follows course of artery. Travels through obturator canal and joins internal iliac vein in pelvis
What does this diagram show about the pathways of the femoral artery and vein?
Vein passes more medially in the thigh
What is this?
Femoral nerve
Describe the pathway of the femoral nerve and its innervation:
-L2-L4 spinal nerve roots
-Deep to inguinal ligament to enter proximal anterior thigh lateral to the femoral artery
-Branches innervate anterior thigh muscles
What is this and describe it:
-Saphenous nerve
-Sensory branch of the femoral nerve that innervates skin over the leg
Label and describe 2:
-Obturator nerve
-L2-L4 nerve roots
-Travels along lateral wall of pelvis and exits through the obturator canal
-Emerges onto superficial surface of adductor brevis and gives rise to branches that innervate medial compartment muscle and sking over medial thigh
What is this?
-Femoral triangle - clinically important area in the proximal anterior thigh
Boundaries:
Lateral - medial border of sartorius
Medial - lateral border of adductor longus
Superior - inguinal ligament
Apex = distally where sartorius and adductor longus meet
What forms the floor of the femoral triangle?
Iliopsoas laterally and pectineus medially
What are these?
Floor of femoral triangle
What are the contents of the femoral triangle?
-Femoral artery
-Femoral vein medial to femoral artery - receives important tributary called the great saphenous vein
-Femoral nerve lies lateral to femoral vein and artery and travels deep to inguinal ligament to enter anterior thigh
What are these and what do they form?
-Close the greater and lesser sciatic notches to form the greater and lesser sciatic foramina
What do the sciatic foramina allow?
Allow structures to pass to and from the pelvis and gluteal region
Wht does this show?
-ischial spine projects from posterior ischium
-Sacrospinous ligament attaches to it
Label and describe:
-Ischial tuberosity
-Bulky prominence of bone at posterior aspect of ischium
-We sit on this part of the pelvis
-Muscles of posterior thigh and the sacrotuberous ligament attach here
Label and describe:
-Ridge of bone between the trochanters on the posterior aspect of the femur
Label and describe:
-Lies just inferior to the trochanters on the posterior aspect of the femur
-Site of muscle attachment
What groups of muscles does the gluteal region contain?
-Two groups of muscles
-Superficial and deep group
What muscles make up the superficial gluteal muscle group?
-Gluteus maximus
-Gluteus medius
-Gluteus minimus
-Tensor fascia latae
Describe gluteus maximus:
-Most superficial gluteal muscle
-Several proximal attachments:
-Most posterior parts of posterior ileal surface
-Sacrotuberous ligament
-Sacrum
-Distal:
-Most fibres insert into iliotibial tract
-Smaller proportion attach onto gluteal tuberosity
What is the action and purpose of gluteus maximus?
-Extensor of the hip and is important for standing from a sitting position
-Also acts as a lateral rotator of the hip
-Inserts into ileotibial tract so stabilises knee joint
Describe gluteus medius and gluteus minimus:
-Medius lies deep to maximus and minimus lies deep to medius
-Similar points of attachment to posterior ileum - both attach to anterior parts of posterior ilium surface
-Both insert onto greater trochanter
-Abduct and laterally rotate hip
What is the importance of gluteus medius and minimus?
-Important for normal gait
-When walking, only one leg in contact with floor at once
-When standing on one leg, gluteus medius and minimus in the limb you are standing on contract and hold the pelvis ‘level’ so it doesn’t tilt to the unsupported side
-If they are weak or paralysed in one limb, pelvis tilts to contralateral side every time the contralateral leg is off the ground, resulting in a limp
Describe the attachments and action of the tensor facia latae:
-Attaches to ASIS and inserts into the ileotibial band which itself inserts onto the lateral part of the proximal tibia
-Contraction tenses the fascia lata and iliotibial band
-Stabilises knee when it is extended and also flexes hip joint but is not a prime mover
What is the innervation to the superficial gluteal muscles?
-Gluteal nerves which leave the sacral plexus in the pelvis via the greater sciatic foramen
Gluteus maximus - inferior gluteal nerve
Gluteus minimus, medius and tensor fascia latae - superior gluteal nerve
What are the deep gluteal muscles?
what are their actions?
-Small muscles that primarily stabilise and laterally rotate the hip joint
They are:
-Piriformis
-Superior and inferior gemelli
-Obturator internus
-Quadratus femoris
What do all of the deep gluteal muscles insert onto?
They all insert onto, or close to, the greater trochanter
What is significant about piriformis?
-Attaches to anterior surface of the sacrum
-Passes through greater sciatic foramen and inserts onto greater trochanter
-Nerves of the sacral plexus lie over it in the pelvis
-Sciatic nerve emerges below its inferior border in the gluteal region
What does this show about the nerves?
-Nerves of sacral plexus lie over the piriformis in the pelvis
-Sciatic nerve emerges below its inferior border
What does the sciatic nerve do in the posterior thigh?
Divides into the tibial and common peroneal (common fibular) nerves
Where do the deep gluteal muscles arise?
-Piriformis - anterior sacrum
-Obturator internus - obturator membrane
-All others ischium
What is the pathway of the obturator internus?
-Arises obturator membrane
-Tendon passes through the lesser sciatic foramen
What muscles does the posterior component of the thigh contain?
-Semimembranosus
-Semitendinosus
-Biceps femoris (long and short head)
-Hamstring part of adductor magnus
What can three of the posterior thigh muscles be grouped into?
-Semimembranosus, semitendinosus and long head of biceps femoris
-Hamstrings
-Span both the hip and knee joints
What is the attachment, actions and innervation of the hamstrings?
-Attached proximally to the ischial tuberosity
-Extend the hip, flex the knee
-innervated by the tibial nerve
What does the bottom left innervate?
Three of the hamstring muscles
Where does the short head of biceps femoris arise and what does it do?
What innervates it?
-Linea aspera
-Flexes the knee but does not move the hip joint
-Common peroneal nerve