Description

This video covers the fascia of the upper limb, including its types, functions, and anatomical distribution in the shoulder, arm, forearm, and hand.

Fascia Functions

• Stabilizes and separates muscles from other internal organs
• Forms compartments
• Passage for nerves, blood vessels, and lymph
• Storage medium for fat and water

Three Types of Fascia

• Superficial Fascia
• Deep Fascia
• Visceral Fascia

Fascia of the Shoulder

• Deltoid Fascia
• Pectoral Fascia
• Infraspinatus Fascia
• Supraspinatus Fascia

Fascia of the Arm

Brachial Fascia (Fascia Brachii)

• Medial Intermuscular Septa (Septum Intermusculare Mediale)
• Lateral Intermuscular Septa (Septum Intermusculare Laterale)
• Deep Lamina (Lamina Profunda)
• Flexor Compartment
• Extensor Compartment
• Vagina Osteofibrosa Extensorum
  • Triceps Muscle
• Vagina Osteofibrosa Flexorum
  • Coracobrachialis
  • Brachialis
• Vagina Fibrosa Flexorum
  • Biceps Brachii

Fascia of the Forearm

Antebrachial Fascia (Fascia Antebrachii)

• Deep Lamina (Lamina Profunda)
• Posterior Intermuscular Septum (Septum Intermusculare Posterior)
• Anterior Intermuscular Septum (Septum Intermusculare Anterior)
• Lateral Compartment
• Posterior Compartment
• Anterior Compartment
• Interosseous Membrane

Vagina Osteofibrosa Lateralis

• Extensor Carpi Radialis Brevis
• Extensor Carpi Radialis Longus
• Brachioradialis

Vagina Osteofibrosa Posterior

• Extensor Digitorum
• Extensor Digiti Minimi
• Extensor Carpi Ulnaris
• Abductor Pollicis Longus

Vagina Osteofibrosa Anterior

• Flexor Digitorum Profundus
• Flexor Pollicis Longus

Vagina Fibrosa Antebrachii

• Pronator Teres
• Flexor Carpi Radialis
• Flexor Digitorum Superficialis
• Flexor Carpi Ulnaris

Fascia of the Hand

• Flexor Retinaculum (Retinaculum Musculorum Flexorum)
• Extensor Retinaculum (Retinaculum Musculorum Extensorum)
• Palmar Aponeurosis (Aponeurosis Palmaris)
• Superficial Dorsal Fascia (Fascia Dorsalis Superficialis)

Dorsal Tendinous Sheaths

• 1 – Tendinous sheath of abductor pollicis longus and extensor pollicis brevis
• 2 – Tendinous sheath of extensores carpi radiales
• 3 – Tendinous sheath of extensor pollicis longus
• 4 – Tendinous sheath of extensor digitorum and extensor indicis
• 5 – Tendinous sheath of extensor digiti minimi
• 6 – Tendinous sheath of extensor carpi ulnaris

Carpal Canal (Canalis Carpi)

• 1 – Tendinous sheath of flexor carpi radialis
• 2 – Tendinous sheath of flexor pollicis longus
• 3 – Common flexor sheath (for flexor digitorum superficialis and flexor digitorum profundus)
• 3.1 – Middle carpal sac (Saccus Carpi Medius)

Ulnar Canal (Canalis Ulnaris / Guyon’s Canal)

• 5 – Ulnar Artery
• 6 – Ulnar Veins
• 7 – Ulnar Nerve

Transcript

Introduction
0:00
What’s up.
0:04
Meditay here and in this video, we’re gonna take a look at the main fascia covering structures
0:09
in the upper extremity.
What is a Fascia?
0:10
But first, we need to answer the questions: what is a fascia is?
0:13
And how do we categorize them?
0:15
So a fascia is just a connective tissue surrounding structures within the body.
0:20
So here is a muscle, just a raw muscle within our body.
0:23
And here is a fascia.
0:24
It surrounds the muscle.
0:26
Now why do we need them?
0:28
Well one thing is that fascia stabilizes and separates muscles from other internal organs.
0:34
Fascia form compartments.
0:36
Specially in clinics if you get patients with edema within the compartment that the fascia
0:40
forms, we’ll get the so-called compartment syndrome, which could be very dangerous as
0:45
blood supply may get cut off due to the pressure.
0:48
Fascia also forms a passage for nerves, blood vessels and lymph.
0:52
And this is also important to keep in mind.
0:54
Specially in people with chronic muscle pain.
0:56
It doesn’t necessarily have to be your muscle that’s ill, it could be the fascia.
1:00
So, stretching exercises are important factors which can stretch the fascia and help loosening
1:05
it up.
1:07
Fascia also function as a storage medium for fat and water.
1:10
And lastly.
1:12
There are three types of fasciae that you need to know.
1:14
These are Superficial fascia, Deep fascia, and Visceral Fascia.
1:19
Ok.
1:20
So here is the skin without removing any layers.
1:23
If you remove just the layers of the skin, you’ll see a superficial fascia, located
1:28
right underneath the skin.
1:30
And then when you remove the superficial fascia, you’ll see the deep fascia.
1:34
The deep fascia surrounds individual muscles and groups of muscles to separate into compartments.
1:41
And when we talk about fascia within the body, it’s most often the deep fascia we’re
1:45
talking about.
1:46
So, when you remove the deep fascia, and enough muscle and bone to see an organ, we’ll see
1:51
the visceral fascia, that surrounds the organs within our body.
1:55
Here we see the fascia covering the lungs, called pleura.
1:59
So that is the three types of fasciae we have And if we go back here.
2:03
This fascia I showed you earlier, was a deep fascia.
2:06
Alright.
Content
2:07
So finally- In this video, we’re first going to look
2:10
at the fascia of the Shoulder.
2:12
Then we’ll make a cross section of the arm and cover the main fascia there.
2:16
Then we’ll cover the fascia in a cross section of the forearm, and then do the same thing
2:20
with the hand.
2:21
So, we’ll start with the fascia of the shoulder.
Fascia of the Shoulders
2:24
Here you see all the muscles of the upper limb.
2:26
Now the fascia of the shoulders isn’t that complicated as they don’t form significant
2:31
compartments like they do in the rest of the upper limb.
2:35
But the first fascia is this one.
2:37
Called the deltoid fascia covering the deltoid muscle, then we have the pectoral fascia,
2:41
which cover the Pectoral Fascia.
2:44
Then if we look at the posterior view of the shoulder, we’ll find the Infraspinatus Fascia
2:48
covering the infraspinatus muscle, and the supraspinatus fascia, for the supraspinatus
2:53
muscle.
2:55
That was generally the most important fascia the shoulder has.
Fascia of the Arm
2:58
Now let’s do the Fascia of the Arm.
3:00
Ok.
3:01
The main surrounding fascia the arm have is the brachial fascia, as you see here, and
3:05
what’s significant with this fascia si that It form compartments.
3:09
So, if you look at a lateral view, you’ll see an anterior compartment and a posterior
3:13
compartment, they’re separated by the brachial fascia.
3:17
So, if we make a cross section, and look at the arm from this perspective, we’ll see
3:21
the Brachial fascia and the humerus in the middle.
3:24
The brachial fascia is connected to the bone through Intermuscular Septae, called the Medial
3:30
Intermuscular Septae, and a Lateral Intermuscular Septae, and they form the flexor compartment,
3:36
and the Extensor Compartment.
3:38
The extensor compartment mainly contains the triceps muscles.
3:42
The flexor compartment however, is actually divided into two smaller compartments by the
3:46
deep lamina, or lamina profunda.
3:48
Superficially, we’ll find the Biceps brachii.
3:52
And deeper to that we’ll find the coracobrachialis and the brachialis muscles.
3:57
Now these compartments have names depending on whether they contain bone or not.
4:03
The extensor compartment in Latin is called Vagina Osteofibrosa Extensorum.
4:08
The flexor compartment taht contain bone is called Vagina Osteofibrosa Flexorum, and the
4:13
superficial compartment is called Vagina Fibrosa Flexorum, it doesn’t contain bone, so it
4:19
doesn’t get the privilege of having the word ‘’osteo’’ before the word fibrosa.
4:23
So that was mainly the fascia of the arm Then we have the fascia of the forearm, which
Fascia of the Forearm
4:28
is called Antebrachial Fascia.
4:30
Now let’s make a transverse cut, and look at it from this perspective, we’ll see the
4:34
Antebrachial Fascia around the Ulna and Radius.
4:38
Between the Ulna and Radius, there’s the interosseous Membrane.
4:42
Then there are two deep fasciae separating the forearm into here compartments.
4:47
The deep fascia is called the Posterior intermuscular septum and the anterior intermuscular septum.
4:53
From the anterior intermuscular septum, there’s another fascia called deep lamina, separating
4:59
the anterior compartment.
5:00
Alright.
5:01
So that’s the outline of fascia in the forearm.
5:04
Now we have a Posterior compartment, an Anterior compartment, and a lateral compartment.
5:10
The Posterior compartment consist of extensor muscles like the Abductor Pollicis Longus,
5:15
Extensor Digitorum, Extensor Digiti Minimi and Extensor Carpi Ulnaris.
5:20
In the Lateral Compartment, we have muscles like the Brachioradialis, Extensor Carpi radialis
5:25
longus and extensor carpi radialis brevis.
5:28
Then in the anterior compartment, we have muscles like the Flexor pollicis longus and
5:33
Flexor Digitorum Profundus.
5:35
Superficially we have muscles like the Flexor Carpi Ulnaris, Flexor Digitorum superficialis,
5:40
Flexor Carpi Radialis and Pronator Teres Now we got Vagina Osteofibrosa Posterior.
5:47
Vagina Osteofibrosa Lateralis.
5:49
Vagina Osteofibrosa Anterior and Vagina Fibrosa Antebrachii.
5:54
So that was the fascia of the forearm.
5:57
Now let’s do the fascia of the hand.
5:59
Aight.
Fascia of the Hand
6:00
The first thing we need to address, are the retinaculum we have in the wrist.
6:05
Once the antebrachial fascia reaches the wrist, it’s going to form a thick band called the
6:10
flexor retinaculum, and an extensor retinaculum.
6:13
These bands are crucial because they organize the blood flow and the tendons of the muscles
6:18
of the forearm into compartments.
6:21
Other fascia associated structures in the hands are the Palmar Aponeurosis, which is
6:26
a continuation of the deep fascia of the forearm, that protects the underlying vasculature.
6:32
Superficially to that we have the superficial palmar fascia.
6:35
While the dorsum of the hand has mainly the superficial dorsal fascia.
6:39
Ok.
6:40
Now let’s first understand the flexor and the extensor retinaculum, by making a transverse
6:45
cut like this, and look at a cross section of the wrist.
6:49
First we’ll see the distal row of the Carpal Bones.
6:51
These are the Trapezium, Trapezoid, Capitatum and Hamatum, right?
6:56
And for orientation, the thumb is here, the pinky is here and the dorsum of the hand is
7:01
here and the palm is here.
7:03
So, if we look at the hand, we’re looking at a cross section of around this region,
7:07
and looking from this perspective.
7:09
Ok.
7:10
Let’s now add structures as we talk about them.
7:13
First, we have the skin.
7:14
Under the skin, we have the extensor retinaculum, and then we have the flexor retinaculum.
7:20
Both form compartments.
7:22
The extensor Retinaculum is going to form 6 canals for the tendons of the extensor muscles
7:27
to go through.
7:28
The first canal closest to the thumb contain tendons of the Abductor pollicis longus and
7:34
extensor pollicis brevis.
7:36
The second canal contain tendons of the extensor carpi radialis longus, extensor carpi radialis
7:42
brevis.
7:43
The third canal contain tendons of the extensor pollicis longus.
7:47
The 4th canal contains tendons of the extensor digitorum and extensor indicis.
7:52
The 5th contains tendons of the extensor digiti minimi
7:56
And the 6th canal contains tendons of the extensor carpi ulnaris muscle.
8:02
These tendons going through the canals that the extensor retinaculum form, are grouped
8:07
as dorsal tendinous sheath as you see here.
8:10
So each canal form a sheath around the tendons to protect them from damage.
8:15
Awesome.
8:16
Now let’s do the flexor retinaculum.
8:18
The flexor retinaculum also from canals.
8:21
The first canal it forms is called the Carpal Canal.
8:25
The carpal canal contains the tendons for the flexor digitorum profundus And Tendons
8:29
of the flexor digitorum superficialis.
8:32
These 8 tendons are groups as tendinous sheath, just like the extensors are.
8:37
Then we have the flexor policis longus, which is also surrounded by its own tendinous sheath.
8:43
Another structure you’ll find in the carpal canal is the median nerve.
8:47
So pressure in the carpal canal can press on the median nerve causing chronic pain.
8:52
Another tendon you’ll find within the flexor retinaculum is the tendon of the flexor carpi
8:57
radialis, which has its own tendinous sheath.
9:00
So, this is how it they all look like.
9:02
You’ll find 3 tendinous sheaths here on the palmar side.
9:05
Then we have the Ulnar Canal, which contain the ulnar nerve, 2 ulnar veins and 1 ulnar
9:11
artery.
9:12
Awesome.
9:13
Other structures we can find, are the thermal muscles and the hypothermal muscles, and between
9:17
them is the tendon for the palmaris longus, but if you make a transverse cut at the middle
9:22
of the hand, you’ll find the palmaris longus continuing as the palmar aponeurosis, where
9:28
the palmar aponeurosis is bound to muscles of the thermal and hypothermal regions.
9:33
So that was all the fascias I wanted to cover in the upper limb, and I hope that was helpful.