This presentation is about the development of the diaphragm along with its functions and clinical significance.

1. Anatomy of
Diaphragm
Dr. Sara Ahmed

2. • The diaphragm is a dome
shaped musculo-tendinous
septum which separates the
thoracic and abdominal
cavitiy.
• It is a chief muscle of
respiration.
• Muscle fibres form the
periphery of the partition
and are inserted into a
central tendon.

3. ORIGIN
The muscle fibres may be
grouped into three parts.
• Sternal
• Costal
• Lumbar

4. STERNAL PART
• The Sternal part consists of
two small muscular slips that
are attached to the posterior
aspect of the xiphoid process.
• On each side of these muscular
slips, there is a small antero-
lateral gap known as "The
Sterno-Costal Hiatus."

5. COSTAL
PART
• The costal part consists of
wide muscular slips that arise
from the internal surface of
the inferior 6 ribs and their
costal cartilage on each side.
• These slips interdigitate with
the transverse abdominis
muscle.

6. LUMBAR PART
• The Lumbar part arises from the
lumbar vertebrae by two musculo
tendinous crura, which are attached
on each side of aorta to the
anterolateral surfaces of the
superior two or three lumbar
vertebrae and their intervertebral
disc.
• The right crus is broader and longer
than the left crus.

7. INSERTION
• The muscular fibres of the
diaphragm converge radially
to a strong, sheet like
aponeurosis called central
tendon.
• It is fused with the inferior
surface of the fibrous
pericardium.
• It is trilobar in shape.

8. • The diaphragm while
separating the thoracic and
abdominal cavities gives
passage to a number of
structures passing in both
directions.
• The major orifices are:
• Vena Caval Foramen
• Oesophageal Hiatus
• Aortic Hiatus
OPENINGS IN THE DIAPHRAGM

9. APERTURE VERTEBRA
L LEVEL
CONTENTS
Vena Caval Foramen T8 Inferior Vena Cava, Right Phrenic Nerve
Oesophageal Hiatus T10 Oesophagus, Anterior and Posterior Vagal
Trunks
Aortic Hiatus T12 Aorta, Thoracic Duct
Two Lesser Apertures in
Right Crus
Greater and Lesser Right Splanchnic Nerves
and Azygous Vein
Two Lesser Apertures in
Left Crus
Greater and Lesser Left Splanchnic Nerves and
Hemiazygous Vein
Behind the Diaphragm,
Under the Medial
Lumbocostal Arch
Sympathetic Trunk

10. ARTERIAL
SUPPLY
SUPERIOR SURFACE:
• Superior Phrenic Arteries
• Musculophrenic and
Pericardiophrenic
Arteries.
INFERIOR SURFACE:
• Inferior Phrenic Arteries

11. SUPERIOR SURFACE:
• Pericardiophrenic vein
• Musculophrenic Vein
INFERIOR SURFACE:
• Right and Left Inferior Phrenic
Vein
VENOUS
DRAINAGE

12. NERVE SUPPLY
• The Phrenic nerves are the sole
motor nerves to the diaphragm
which arises from the ventral
rami of segments C3, C4 and C5
of the spinal cord.
• Also supply sensory fibres to
most of the diaphragm.
• Peripheral parts also receive
supply from inferior 6 or 7
intercostal nerves and subcostal
nerves.

13. • Diaphragm is the principal muscle of
inspiration.
• Diaphragm acts in all expulsive acts to
give additional power to each effort.
• The sphincteric action in the lower end
of oesophagus is due to the contraction
of the intrinsic muscle in the lower 2 cm
of the oesophagus.
ACTIONS

14. DEVELOPMENT
Diaphragm develops from the following
sources:
Septum Transversum
forms the central
tendon.
Pleuroperitoneal
Membranes form the
dorsal paired portion.
Lateral thoracic wall
contributes to the
circumferential portion
of the diaphragm.
Dorsal mesentry of the
oesophagus forms the
dorsal unpaired portion.

15. CLINICAL
ANATOMY
• Hiccough or hiccup is the result of
spasmodic contraction of the
diaphragm.
• Shoulder Tip Pain: Irritation of the
diaphragm may cause referred
pain in the shoulder.
• Unilateral paralysis of the
diaphragm due to a lesion of the
phrenic nerve anywhere along its
course is a common occurence.

16. EVENTRATION OF DIAPHRAGM:
• Eventration is a condition in
which all or part of the
diaphragm is largely composed of
fibrous tissue with only a few or
no interspersed muscle fibres.
• It is usually congenital but maybe
acquired.
• It can be complete or partial.

17. DIAPHRAGMATIC HERNIAS:
Diaphragmatic Hernias can be
congenital or acquired.
I CONGENITAL:
• Posterolateral/ Bochdalek Hernia
• Retrosternal/ Morgagni Hernia
• Posterior Hernia
• Central Hernia
II ACQUIRED:
• Traumatic Hernia
• Hiatal Hernia

18. 1. POSTEROLATERAL HERNIA:
• It is the commonest type of congenital
diaphragmatic hernia.
• It occurs through the pleuroperitoneal
hiatus or foramen of bochdalek.
• It is situated at the periphery of the
diaphragm in the region of
attachments to the 10th and 11th rib.
• It is more common on the left side.
CONGENITAL HERNIA

19. 2. RETROSTERNAL HERNIA:
It occurs through the spaces between
the xiphoid and costal origins of the
diaphragm called the foramen of
Morgagni.
3. POSTERIOR HERNIA:
This is due to the failure of development of
the posterior part of the diaphragm.
One or both the crus may be absent.
4. CENTRAL HERNIA:
It is a rare, left sided and supposed to be the
result of rupture of the foetal membranous
diaphragm in the region of the left dome.
Retrosternal Hernia

20. ACQUIRED
HERNIA
1. TRAUMATIC HERNIA:
Traumatic Hernias are most commonly
seen following blunt non penetrating
trauma to the chest in road traffic
accidents or fall from a height.
2. HIATAL HERNIA:
• Congenital Hiatal Hernia:
It is due to the persistence of an
embryonic peritoneal process in the
posterior mediastinum in front of the
cardiac end of the stomach.
It is also called rolling type of hernia.

21. • Acquired Hiatal Hernia:
Acquired Hiatal Hernia is also known as the sliding type of hernia. It is
the commonest of all internal hernias. It is due to the weakness of the
phrenico oesophageal membrane which is formed by the reflection of the
diaphragmatic fascia to the lower end of the oesophagus.

22. THANK YOU