Anterior and medial thigh

Question 1

What is the fascia lata?

Answer 1

The fascia lata is a deep fascial investment of the musculature of the thigh, and is analogous to a strong, extensible, and elasticated stocking. It begins proximally around the iliac crest and inguinal ligament, and ends distal to the bony prominences of the tibia.

Question 2

Where is the fascia lata at its thickest?

Answer 2

It is thickest along the superolateral aspect of the thigh, where it arises from the fascial condensations of gluteus maximus and medius.
It is also thick around the knee where the fascia receives reinforcing fibres from tendons of the quadriceps muscles.

Question 3

What are the intermuscular septa?

Answer 3

Derived from the fascia lata
The septa divide the thigh musculature into three compartments; anterior, medial, and lateral.
The lateral intermuscular septum is the strongest of the three due to reinforcement from the iliotibial tract.

Question 4

What is the saphenus opening?

Answer 4

An ovoid hiatus known as the saphenous opening is present in the fascia lata just inferior to the inguinal ligament. The opening serves as an entry point for efferent lymphatic vessels and the great saphenous vein, draining into superficial inguinal lymph nodes and the femoral vein respectively.

Question 5

What is the iliotibial tract?

Answer 5

The iliotibial tract (sometimes known as the iliotibial band or IT band) is a longitudinal thickening of the fascia lata, which is strengthened superoposteriorly by fibres from the gluteus maximus.

Question 6

What does the iliotibial tract do?

Answer 6

Acts as an extensor, abductor and lateral rotator of the hip, with an additional role in providing lateral stabilisation to the knee joint.
Forms a sheath around the tensor fascia lata muscle.

Question 7

What is the tensor fascia lata?

Answer 7

The tensor fascia lata is a gluteal muscle that acts as a flexor, abductor, and internal rotator of the hip.
The muscle originates from the iliac crest, and at the junction of the middle and upper thirds of the thigh, it inserts into the anterior aspect of the iliotibial tract.

Question 8

What innervates the tensor fascia lata?

Answer 8

It is innervated by the superior gluteal nerve, like gluteus medius and minimus, but is located more anterolaterally than the other gluteal muscles.

Question 9

What are the major features of the femur?

Answer 9

Head - articulates with the acetabulum of the pelvis
Neck - connects the head to the shaft
Greater trochanter - site of attachment for many of the muscles in the gluteal region, such as gluteus medius, gluteus minimus and piriformis
Lesser trochanter - site of attachment for iliopsoas
Intertrochanteric line - a ridge of bone between the trochanters
Intertrochanteric crest - ridge of bone that connects the two trochanters, site of attachment for quadratus fermoris
Linea aspera - roughened ridges of bone on posterior shaft
Pectineal line - medial border of linea aspera
Gluteal tuberosity - lateral border of linea aspera, posterior of shaft, attachment for gluteus maximus
Medial and lateral condyles - articulate with the tibia, menisci of the knee and patella
Medial and lateral epicondyles - origin of collateral ligaments
Intercondylar fossa - deep notch between condyles

Question 10

What is the patella?

Answer 10

The patella has a triangular shape, with anterior and posterior surfaces. The apex of the patella is situated inferiorly, and is connected to the tibial tuberosity by the patella ligament. The base forms the superior aspect of the bone, and provides the attachment area for the quadriceps tendon.

Question 11

How does the patella articulate with the femur?

Answer 11

The posterior surface of the patella articulates with the femur, and is marked by two facets:
Medial facet – articulates with the medial condyle of the femur.
Lateral facet – articulates with the lateral condyle of the femur.

Question 12

What are the functions of the femur?

Answer 12

Leg extension – Enhances the leverage that the quadriceps tendon can exert on the femur, increasing the efficiency of the muscle.
Protection – Protects the anterior aspect of the knee joint from physical trauma.

Question 13

What is the ligamentum patellae?

Answer 13

Connected to the lower end of the patella, point of attachment on the tibial tuberosity

Question 14

What are the major features of the tibia?

Answer 14

Medial and lateral condyles - proximal and aid weight-bearing
Tibial plateau - articulates with the femoral condyles
Medial and lateral intercondylar tubercles - main site of attachment for the ligaments and the menisci of the knee joint
Tibial tuberosity - the attachment site for the patella ligament.
Soleal line - the site of origin for part of the soleus muscle, and extends inferomedially
Medial malleolus - articulates with the tarsal bones to form part of the ankle joint
Fibular notch - where the fibula is bound to the tibia – forming the tibiofibular joint.

Question 15

What is the fibula?

Answer 15

The fibula is a bone located within the lateral aspect of the leg.

Question 16

What is the function of the fibula?

Answer 16

Its main function is to act as an attachment for muscles, and not as a weight-bearer.

Question 17

What are the articulations of the fibula?

Answer 17

Proximal tibiofibular joint – articulates with the lateral condyle of the tibia.
Distal tibiofibular joint – articulates with the fibular notch of the tibia.
Ankle joint – articulates with the talus bone of the foot.

Question 18

What are the major features of the fibula?

Answer 18

Head - articulation with the lateral condyle of the tibia
Neck - common fibular nerve can be found here
Shaft
Lateral malleolus - more prominent, palpable at the ankle

Question 19

What are the key features of the muscles in the anterior compartment of the thigh?

Answer 19

The muscles in the anterior compartment of the thigh are innervated by the femoral nerve (L2-L4), and as a general rule, act to extend the leg at the knee joint.

Question 20

What makes up the iliopsoas?

Answer 20

The iliopsoas is actually two muscles, the psoas major and the iliacus. They originate in different areas, but come together to form a tendon, hence why they are commonly referred to as one muscle.

Question 21

What is the iliopsoas?

Answer 21

The psoas major originates from the lumbar vertebrae, and the iliacus originates from the iliac fossa of the pelvis. They insert together onto the lesser trochanter of the femur.
Flexes the thigh (not extend!)
Psoas major is innervated by anterior rami of L1-3
Iliacus is innervated by the femoral nerve

Question 22

What makes up the quadratus femoris?

Answer 22

Main extensor of the knee
Attach to the patella via the quadriceps tendon
- Vastus Lateralis
- Vastus Intermedius
- Vastus Medialis
- Rectus Femoris

Question 23

What is the vastus lateralis?

Answer 23

Originates from the greater trochanter and the lateral lip of linea aspera.
Extends the knee joint and stabilises the patella.
Innervated by the femoral nerve

Question 24

What is the vastus intermedius?

Answer 24

Attaches to the anterior and lateral surfaces of the femoral shaft.
Extends the knee joint and stabilises the patella.
Innervated by the femoral nerve

Question 25

What is the vastus medialis?

Answer 25

Attached to the intertrochanteric line and medial lip of the linea aspera.
Extends the knee joint and stabilises the patella, particularly due to its horizontal fibres at the distal end.
Innervated by the femoral nerve.

Question 26

What is the rectus femoris?

Answer 26

Originates from the anterior superior iliac spine and the ilium. It runs straight down the leg and attaches to the patella via the quadriceps femoris tendon.
The only muscle of the quadriceps to cross both the hip and knee joints. It flexes the thigh at the hip joint, and extends at the knee joint.
Innervated by the femoral nerve.

Question 27

What is the sartorius?

Answer 27

Longest muscle in the body. It is long and thin, running across the thigh in a inferomedial direction.
Originates from the anterior superior iliac spine, and attaches to the superior, medial surface of the tibia.
At the hip joint, it is a flexor, abductor and lateral rotator. At the knee joint, it is also a flexor.
Innervated by the femoral nerve.

Question 28

Why is the pectineus muscle sneaky?

Answer 28

The pectineus muscle is a flat muscle that forms the base of the femoral triangle. It has a dual innervation, and thus can be considered a transitional muscle between the anterior thigh and medial thigh compartments.

Question 29

What is the pectineus muscle?

Answer 29

It originates from the pectineal line on the anterior surface of the pelvis, and attaches to the pectineal line on the posterior side of the femur, just inferior to the lesser trochanter.
Action: Adduction and flexion at the hip joint.
Innervated by the femoral nerve

Question 30

What are the key features of the muscles in the medial compartment of the thigh?

Answer 30

The muscles in the medial compartment of the thigh are collectively known as the hip adductors. There are five muscles in this group; gracilis, obturator externus, adductor brevis, adductor longus and adductor magnus.
All innervated by the obturator nerve.

Question 31

What is the adductor magnus?

Answer 31

Divided into two parts; the adductor part, and the hamstring part.
Attachments:
Adductor part - originates from the inferior rami of the pubis and the rami of ischium, attaching to the linea aspera of the femur.
Hamstring part - Originates from the ischial tuberosity and attaches to the adductor tubercle and medial supracondylar line of the femur.
Both act to adduct the thigh. Adductor part also flexes the thigh and the hamstring part extends it.
Adductor innervated by the obturator nerve.
Hamstring innervated by the sciatic nerve.

Question 32

What is the adductor longus?

Answer 32

Originates from the pubis, and expands into a fan shape, attaching broadly to the linea aspera of the femur
Acts to adduct the thigh
Innervated by the obturator nerve

Question 33

What is the adductor brevis?

Answer 33

Lies underneath the adductor longus.
Originates from the body of pubis and inferior pubic rami. It attaches to the linea aspera on the posterior surface of the femur, proximal to the adductor longus.
Innervated by the obturator nerve

Question 34

What is the Obturator Externus?

Answer 34

It originates from the membrane of the obturator foramen, and adjacent bone. It passes under the neck of femur, attaching to the posterior aspect of the greater trochanter.
Adduction and lateral rotation of the thigh.
Innervated by the obturator nerve

Question 35

What is the Gracilis?

Answer 35

Most superficial and medial
Crosses hip and knee joints
It originates from the inferior rami of the pubis, and the body of the pubis. Descending almost vertically down the leg, it attaches to the medial surface of the tibia.
Adduction of the thigh at the hip, and flexion of the leg at the knee.
Innervated by the obturator nerve

Question 36

What are the borders of the femoral triangle?

Answer 36

Superior border – Formed by the inguinal ligament
Lateral border – Formed by the medial border of the sartorius muscle.
Medial border – Formed by the medial border of the adductor longus muscle. The rest of this muscle forms part of the floor of the triangle.
Roof formed by the fascia lata
Base formed by the pectineus, iliopsoas and adductor longus muscles.

Question 37

What is the contents of the femoral triangle?

Answer 37

Femoral nerve – Innervates the anterior compartment of the thigh, and provides sensory branches for the leg and foot.
Femoral artery – Responsible for the majority of the arterial supply to the lower limb.
Femoral vein – The great saphenous vein drains into the femoral vein within the triangle.
Femoral canal – A structure which contains deep lymph nodes and vessels.

Question 38

What is the femoral sheath?

Answer 38

The femoral artery, vein and canal are contained within a fascial compartment – known as the femoral sheath.

Question 39

How can you remember the contents of the femoral triangle?

Answer 39

NAVEL!
N: Nerve.
A: Artery.
V: Vein.
E: Empty space (this is important as it allows the veins and lymph vessels to distend, so they can cope with different levels of flow).
L: Lymph canal

Question 40

What is the adductor canal?

Answer 40

The adductor canal (Hunter’s canal, subsartorial canal) is a narrow conical tunnel located in the thigh.
It is approximately 15cm long, extending from the apex of the femoral triangle to the adductor hiatus of the adductor magnus. The canal serves as a passageway from structures moving between the anterior thigh and posterior leg.

Question 41

What are the borders of the adductor canal?

Answer 41

Anteromedial: Sartorius.
Lateral: Vastus medialis.
Posterior: Adductor longus and adductor magnus.

Question 42

What is the adductor hiatus?

Answer 42

A gap between the adductor and hamstring attachments of the adductor magnus muscle.

Question 43

What is the contents of the adductor canal?

Answer 43

It transmits the femoral artery, femoral vein, nerve to the vastus medialis and the saphenous nerve – the largest cutaneous branch of the femoral nerve.
As the femoral artery and vein exit the canal, they are called the popliteal artery and vein respectively.

Question 44

What is a femoral hernia?

Answer 44

There is a gap between the inguinal ligament and the superior pubic ramus where the femoral vessels and nerve pass from the back of the abdomen into the thigh. If the bowel also passes through the medial part of this pace, it is called a femoral hernia.

Question 45

How can you take blood from the femoral artery?

Answer 45

Where the external iliac artery becomes the femoral artery it is running in front of the hip joint and the pulse can be easily felt. A needle can be passed into the artery to take an arterial blood sample or a needle can be passed just medial to the artery to penetrate the femoral vein and take a venous blood sample.

Question 46

How would paralysis of quadriceps occur?

Answer 46

The femoral nerve supplies all the muscles in the anterior compartment of the thigh and any damage or disease of the nerve may lead to paralysis of the whole compartment.

Question 47

What happens in Patellar dislocation?

Answer 47

The hip joint is directly above the knee joint which is directly above the ankle joint. However, because of the neck of the femur, the shaft of the femur meets the shaft of the tibia at a slight angle. The pull of the quadriceps tends to pull the patella laterally and sometimes it dislocates. The vastus medialis and the depth of the patella are structured to resist the lateral displacement of the patella.