Description

In this video, we go through the full anatomy of the femur, dividing it into its three major regions: the proximal end, the shaft (body), and the distal end.

Structures of the Femur

Proximal End of the Femur

Head of femur (caput femoris): Spherical structure that articulates with the acetabulum of the pelvis to form the hip joint.
Fovea of the head (fovea capitis femoris): Small pit on the medial surface of the femoral head where the ligament of the head of femur attaches.
Neck of femur (collum femoris): Narrow region connecting the head to the shaft, commonly fractured in elderly individuals.
Greater trochanter (trochanter major): Large lateral projection providing insertion for gluteus medius, gluteus minimus, piriformis, superior gemellus, inferior gemellus, and obturator internus.
Trochanteric fossa (fossa trochanterica): Depression on the medial side of the greater trochanter where obturator externus inserts.
Lesser trochanter (trochanter minor): Posteromedial projection for insertion of the iliopsoas muscle.
Intertrochanteric line (linea intertrochanterica): Anterior ridge running between the greater and lesser trochanters; attachment site for the iliofemoral ligament and origin of vastus medialis and vastus lateralis.
Intertrochanteric crest (crista intertrochanterica): Posterior ridge connecting the trochanters; contains the quadrate tubercle.
Quadrate tubercle (tuberculum quadratum): Site of insertion for quadratus femoris muscle.

Shaft of the Femur (Corpus femoris)

Pectineal line (linea pectinea): Ridge on the posterior surface for insertion of pectineus muscle.
Gluteal tuberosity (tuberositas glutea): Posterior surface ridge for insertion of gluteus maximus.
Linea aspera (linea aspera): Prominent ridge running down the posterior shaft; composed of medial and lateral lips and an intermediate zone.
Medial lip (labium mediale): Site for origin of vastus medialis, adductor longus, adductor brevis, and insertion of adductor magnus.
Lateral lip (labium laterale): Site for origin of vastus lateralis, short head of biceps femoris, and lateral intermuscular septum.
Intermediate zone (zona intermedia): Central part of linea aspera.
Medial supracondylar line (linea supracondylaris medialis): Continuation of medial lip; attachment for adductor magnus.
Lateral supracondylar line (linea supracondylaris lateralis): Continuation of lateral lip; origin of plantaris muscle.
Anterior surface (facies anterior): Located between medial and lateral borders; origin of vastus intermedius.
Posterior surface (facies posterior): Upper back surface of the shaft.
Popliteal surface (facies poplitea): Triangular area on the posterior surface near the distal end.
Medial surface (facies medialis): Located between anterior and medial borders.
Lateral surface (facies lateralis): Located between anterior and lateral borders.
Medial border (margo medialis): Separates medial and anterior surfaces.
Lateral border (margo lateralis): Separates lateral and anterior surfaces.

Distal End of the Femur

Medial condyle (condylus medialis): Large, rounded medial projection for articulation with tibia.
Lateral condyle (condylus lateralis): Large, rounded lateral projection also articulating with tibia.
Medial epicondyle (epicondylus medialis): Prominence above the medial condyle; attachment site for tibial collateral ligament.
Adductor tubercle (tuberculum adductorium): Located on medial epicondyle; insertion site for adductor magnus.
Lateral epicondyle (epicondylus lateralis): Prominence above the lateral condyle; attachment site for fibular collateral ligament.
Groove for popliteus (sulcus musculi poplitei): Small groove on lateral condyle for popliteus muscle tendon.
Intercondylar fossa (fossa intercondylaris)
Intercondylar line (linea intercondylaris)
Patellar surface (facies patellaris): Smooth anterior surface between condyles that articulates with the patella.

Clinical Notes

Femoral neck fractures: Common in older adults, especially postmenopausal women; can compromise blood supply.
Supracondylar fractures: Common in pediatric populations; can damage neurovascular structures.
Hip flexor injuries: Involving the lesser trochanter and iliopsoas tendon.

Sources:

Kozlowski, T. (2017). Memorix Anatomy, 2nd ed.
Standring, S. (2020). Gray’s Anatomy, 42nd edition
White TD, Folkens PA. (2005). The Human Bone Manual

Programs used: Complete Anatomy (3D4Medical), PowerPoint, Canva, Camtasia

Transcript

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With age comes wisdom. However, so do falls
that can lead to fractures. And one of the

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most serious injuries we see in older adults is a
fracture of the femur near the hip. To understand

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why this happens, we need to understand how the
femur is built, where forces are distributed,

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and how it connects with the muscles around it.
The Femur is the next bone in our

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lower limb skeletal series.
So in this video, we’re going to

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break down the full anatomy of the femur, going
through its parts, surface landmarks, and muscle

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attachments. And as always, I’ll highlight some
important clinical correlations along the way.

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What’s up everyone, my name is Taim. I’m a medical
doctor, and I make animated medical lectures to

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make different topics in medicine visually easier
to understand. If you’d like a PDF version or a

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quiz of this presentation, you can find it on
my website, along with organized video lectures

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to help with your studies.
Alright, let’s get started.

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This is how I understand everything regarding
the femur. I start by dividing it into a proximal

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part, the body of the femur, and a distal
end. Let’s just orientate ourselves first.

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The femur we’re looking at now is the posterior
view, and here on the left side of the screen

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is the anterior view. Let’s now isolate the
bones and start with the proximal part first.

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The first structure we see is the
head of the femur. It’s this smooth,

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rounded part that forms part of the hip
joint. Just beneath that, narrowing off,

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is the neck of the femur, and this is a really
important region, because this is where a lot of

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hip fractures in older adults tend to happen.
Let’s now add the femur back into the pelvis

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to see this in context. You can now see
how the head of the femur fits perfectly

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into the acetabulum. And surrounding the head
and neck, we’ve got all the ligaments and the

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capsule that make up what we call the hip joint.
Now if we look at the medial side of the femoral

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head, you’ll notice this little indentation,
that’s the fovea of the head of the femur. And

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the hip joint actually has a small ligament
that attaches right here. It’s not the main

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stabilizer of the joint, but it does carry a
small artery that’s important early in life.

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So, in context, here you see the femoral head
sitting inside the acetabulum. I’ve faded the

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hip bone a bit so you can see this more clearly.
And right here, you can see how the ligament of

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the head of the femur attaches to that fovea.
Another thing is, the head of the femur actually

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articulates with the lunate surface of the
acetabulum, and in this space right here,

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it’s cushioned by the acetabular fat pad. If you
want to learn more about the hip joint in detail,

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I covered that in the previous video, feel
free to check that out. But let’s move on and

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continue with the rest of the proximal femur.
The next structure we see is the greater

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trochanter. The greater trochanter is a really
important part of the bone because so many muscles

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from the hip insert right into this area. You
can see here, we’ve got gluteus medius, gluteus

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minimus, piriformis, superior gemellus, inferior
gemellus, and the obturator internus, all of them

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attaching right onto the greater trochanter.
But if you look closely, you’ll see the greater

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trochanter also forms something called the
trochanteric fossa. What’s interesting is,

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right on the opposite side of the obturator
internus, we can see another muscle called the

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obturator externus. If we just tilt the femur
slightly here, you can see how the external

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obturator muscle inserts right into this fossa.
Now, since we’ve got a greater trochanter,

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we also have a lesser trochanter.
This is a smaller bony bump located on the

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posterior-medial side of the femur. And it serves
as the insertion point for the iliopsoas muscle,

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which is the main flexor of the hip joint. So
every time you lift your knee or flex your thigh,

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this area is getting pulled at.
The next structure we can see is

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the intertrochanteric line. You’ll find it
running diagonally on the anterior surface,

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connecting the greater and lesser trochanters.
It acts as an attachment site for the capsule

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and the iliofemoral ligament of the hip joint,
and it also gives origin to part of the vastus

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medialis and vastus lateralis muscles.
On the other side, the posterior view,

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we can see the intertrochanteric crest. This
is a more prominent ridge that also links the

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greater and lesser trochanters, but on the back
side. And there’s a small bump along this crest

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called the quadrate tubercle, and that’s
where the quadratus femoris muscle inserts.

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So those are the main features of the
proximal part of the femur. Let’s now

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move on to the femoral shaft, and for
now, we’ll focus on the posterior surface.

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Starting from the top again, here’s the
pectineal line where the pectineus muscle

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inserts. Just lateral to it, you’ll see the
gluteal tuberosity. That’s where the gluteus

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maximus muscle inserts. Both of these landmarks
are pretty easy to remember because they’re

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named after the muscles that attach to them.
Running down the posterior shaft is a long,

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rough ridge called the linea aspera. And
it’s made up of a medial lip, a lateral lip,

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and the intermediate zone in between. As
we reach the lower third of the femur,

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the linea aspera splits into two ridges,
the medial and lateral supracondylar lines.

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Now. let’s move back up again, here we see the
pectineus muscle attaching onto the pectineal

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line, and here’s the gluteus maximus,
inserting onto the gluteal tuberosity.

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Now, around the medial lip of the linea
aspera, you’ve got the attachment of the medial

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intermuscular septum, the origin of the vastus
medialis, and the insertions of the adductor

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longus, adductor brevis, and adductor magnus.
I’ve faded adductor magnus so you can slightly

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see the outline on this model. Along the lateral
lip, we’ve got the lateral intermuscular septum,

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the origin of short head of the biceps femoris,
and the vastus lateralis. The intermediate zone

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runs between these two lips, and while it’s
not a primary site for major muscle attachment,

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it forms the central portion of the
ridge as it continues down the shaft.

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The medial supracondylar line gives
attachment to the adductor magnus muscle,

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and the lateral supracondylar line
gives origin to the plantaris muscle.

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So that’s these landmarks. Other surfaces you’ll
come across on the posterior view is the the

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posterior surface of the femur up here, and also
the popliteal surface down toward the distal end.

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Then we have the lateral surface and the medial
surface. And if we now focus on the anterior view,

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you’ll notice two distinct borders here,
the medial border and the other called the

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lateral border. Between these two borders lies the
anterior surface, which gives origin to the vastus

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intermedius muscle, one of the quadriceps muscles.
Alright, that was everything for the shaft of the

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femur. Let’s now move down and look at the
distal end. So let’s go ahead and zoom in.

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The distal femur consists of two large rounded
areas: the lateral condyle and the medial condyle.

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These are the weight-bearing parts that articulate
with the tibia and patella at the knee joint.

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Let’s start with the medial side. The medial
condyle has a medial epicondyle on its outer

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surface, and just above that, we find the
adductor tubercle. The adductor magnus

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muscle inserts right onto this tubercle, while
the tibial collateral ligament attaches more

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inferiorly on the medial epicondyle. Also
attaching here on the medial condyle is the

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medial head of the gastrocnemius muscle.
Now moving over to the lateral condyle,

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we have the lateral epicondyle. This is where
the fibular collateral ligament attaches,

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and just below that, there’s a small groove called
the groove for the popliteus. The popliteus muscle

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runs right through this groove as you see
here. The medial condyle is also where the

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lateral head of the gastrocnemius originates.
So those were the main bony features and muscle

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attachments around the condyles.
A few more things to mention.

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Between the condyles on the posterior side is
the intercondylar fossa, and just above it is

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the intercondylar line. On the anterior
side, you’ll find the patellar surface,

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which is the smooth area that articulates with
the patella to form part of the knee joint.

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Now. When you look at this, there’s a reason
the femur is not straight, it has this natural

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curve and angulation that helps it handle
and redirect forces more efficiently as we

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move. When we’re standing or walking, forces
travel through the femur in two directions:

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from the hip down under body weight and up from
the ground through the tibia. That curve the

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femur has actually causes stress to concentrate in
certain zones, like the femoral neck and condyles.

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These are the major “energy transfer areas”
in the bone, structurally reinforced to

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handle loads, but also more vulnerable
to fractures, especially in older adults.

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And that’s everything I had for the femur, its
landmarks, surfaces, and muscle attachments.

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In the next video in this lower limb
skeletal series, we’ll be covering the

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joint right in this region. The knee joint, how
it’s built, its capsules, the different pockets,

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and the most common injuries. Click
the next video, and I’ll see you there.

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If you want a handmade PDF version of this
lecture, take a quiz to test your knowledge,

0:08:47.680,0:08:50.000
or access an organized list of all my videos,

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you can find everything on my website.
Thanks for watching! See you in the next one.