1.
Anatomy of Neck & its
Medicolegal importance.
Presenter Dr Gopal G Hargi
PG in FM& T

2.
 Neck is a very prominent & vital part .Even
trivial injuries can cause death without
showing any signs. There are very vital
structures in a relatively small & unprotected
anatomic region making it very vulnerable to
fatal injuries.
 Moreover the Neck is an area which can be
easily grasped and immobilized

3.
Anatomy and Physiology

4.
 Lower border of mandible lies b/w C2 & C3.
 The front of the lower pharynx & upper
oesophagus lie the larynx & trachea.
 On each side of the pharynx is the carotid
sheath,containing the common & internal
carotid arteries & the IJV with the cervical
sympathetic trunk behind it.
 The Platysma –a broad flat sheet of muscle
lies superficial to the layers of fascia.

5.
 Coll’s fascia :The space among the structures of
neck are filled with loose areolar tissue.The
structures of the neck are mostly supplied to move
up & down
 .This fascia is a laminar condensation of loose
areolar tissue in neck produced by the movements
of these structures.
 These laminar condensations take different names
in different regions & are continuous with each
other or indirectly.
 These loose areolar tissue form sheaths which
enclose muscles and their moving structures

6.
MODIFICATIONS/
LAMINAE/EXTENSIONS OF DEEP
CERVICAL FASCIA
HAS 7 MODIFICATIONS
1. INVESTING LAYER
2. PRETRACHEAL LAYER
3. PREVERTEBRAL LAYER
4. CAROTID SHEATH
5. BUCCOPHARYNGEAL FASCIA
6. TEMPORAL FASCIA
7. PHARYNGOBASILAR FASCIA

7.
INVESTING LAYER
 ATTATCHMENTS
 ABOVE- EXTERNAL OCCIPITAL PROTUBERANCE,MASTOID PROCESS, EXTERNAL ACOUSTIC
MEATUS, BASE OF THE MANDIBLE
 BELOW- SPINE OF SCAPULA, ACROMION PROCESS, CLAVICLE, MANUBRIUM STERNI
 FRONT- HYOID BONE & CONTINUOUS WITH THE FASCIA OF THE FASCIA OF THE OPPOSITE
SIDE
 BEHIND- 7TH CERVICAL VERTEBRA, LIGAMENTUM NUCHAE

8.
 CCA ,arises from the left side of AOA.
 It lies in the medial part of carotid sheath .
 Upper border of C4 the CCA bifurcates.
 The carotid pulse can be felt by pressing against
the anterior tubercle of the tranverse process of
C6 vertebra.
 ICA ,at its commencment there is a bulge ,
 here the arterial wall is thin & contains the
baroreceptors which is supplied by the 9th & 10th
nerves which control the CVS .
 carotid body is a small structure behind the
bifurcation of CCA & contains baroreceptors which
maintain oxygen saturation.

9.
 IJV forms a jugular arch in the suprasternal
space i.e between the sternal & clavicular
head of sternocleadomastoid tendon.
 Larynx lies below the hyoid bone in the
midline of the neck at the level of C4-C6
vertebra.

10.
 The AJV commences beneath the chin & passes
downwards ,side by side beneath the platysma to
the suprasternal region.Here they pierce the deep
fascia & come to lie in the suprasternal space.
 Carotid sheath consists of a network of areolar
tissue that surrounds the carotid
arteries(c&i),IJV,Vagus nerve & some deep cervical
lymph nodes.
 It is thin where it overlies the IJV ,allowing the
vein to dilate during increased blood flow.

11.
 The thyroid gland is situated low down at the front
of the neck.The 2 symmetrical lobes are connected
by isthmus which lie in front of 2nd,3rd & 4th
tracheal rings.
 Trachea begins at the level of C6 vertebra in
continuity of the larynx,The cervical part lies in
the midline of the neck ,in contact with the front
of the oesophagus.
 Oesophagus commences in continuity with the
pharynx at the level of lower border of the cricoid
cartilage(C6).

12.
 Hyoid bone lies free ,suspended by muscles & so
very mobile .Above its attached to floor of mouth &
tongue,larynx below,behind to epiglottis &
pharynx.It lies at the level of C3 vertebra.
 Vertebral artery arises from subclavian artery &
passes up to traverse the foramen of transverse
process of upper 6 cervical vertebras.On emerging
from foramen the artery enters the skull through
foramen magnum
 .It pierces the spinal dura mater & archnoid and at
the lower border of pons forms the basillar artery.

13.
 For judging the severity of the injuries to the neck
its divided into 3 zones.
 Zone I
• highest mortality
 Zone II
• most frequent site of injury
• lower mortality
 Zone III
• neurological
• distal carotids
• pharyngeal injuries

14.
Zones of the Neck

15.
 (Zone 1)Thoracic inlet (clavicle)to cricoid
cartilage
significant injury in the zone I region may be hidden
from inspection of the chest or the mediastinum.
 subclavian vessels
 brachiocephalic veins
 common carotid artery
 jugular vein
 aortic arch
 Trachea
 esophagus
 Lung apices
 c spine
 spinal cord
 CN roots

16.
Zone 2
 Carotid and vertebral
arteries
 jugular veins
 pharynx
 larynx
 trachea
 esophagus
 c spine
 spinal cord
Cricoid cartilage to angle of mandible

17.
Zone 3
 Salivary glands
 parotid gland
 esophagus
 trachea
 c spine
 Carotid arteries
 jugular veins
 CN IX - XII
Angle of mandible to base of skull

18.
 Injury above the level of C4 –rapid death
 Due to disruption of CV centre.
 Causes- Hyperextension & hyperflexion
Atlanto-occipital injury---fatal: widening of space
with some blood palpated as ‘loosening ‘
Of the junction with widening.Severe form the
articulating condyles of atlas can be seen within
foraen magnum.
C1-C2 injury-- neurogenic shock ,odontoin is #
C2-C3 #( HANGMAN #) rapid

19.
 Injuries over the region of neck
 A) Homicidal:
 a)strangulation
 i)Ligature ii) Manual
 c)bansdola
 e)mugging
 f)penetrating injuries
 a) knife b) gunshot
 g)cut throat injuries
 h)blunt force impact
 i) homicidal ii) accidental

20.
 Blunt force impact to the side of neck
 Shearing
 excessive rotation/ hyperextension
◦ distention and stretching
 Tearing of Vertebral Artery
 The carotids too get dissected ,veins damaged

 Blood tracks along upper part of vessel & enters
the cranial cavity producing massive SAH
 .

21.
Impact Anterior Neck
 Impact Anterior Neck
 Crush larynx or trachea; cricoid ring
 compress esophagus against spinal column
 sudden increased intratracheal pressure against
closed glottis (seatbelt), crush bruise (clothesline
tackle)
 rapid acceleration/ deceleration results in tracheal
injury

22.
 B) Suicidal
a)Hanging b)postural asphyxiation
◦ children with neck over object and body weight produces
compression
 C)Accidental
i)carotid sleepers ii)bar arm control
 a)choking
 b)RTA : rapid deceleration  hyperflexion,
hyperextension, and rotation  vascular structures
are stretched over the cervical spine  shearing
forces create intimal tears in the vessel wall
c)toxic gas inhalation
 D)Judicial or justified hanging

23.
Cause of death in hanging
 Asphyxia
 Venous congestion
 Cerebral oedema
 # vertebra
 Significant cervical spine and spinal cord damage
can occur in hangings that involve a fall from a
distance greater than the body height.
Cause of death in strangulation
 Vagal inhibition
 Asphyxia
 Cerebral anoxia & Venous congestion

24.
 Other consequences of Neck Trauma
Subcutaneous emphysema
 Tension pneumothorax
 Traumatic asphyxia
◦ Penetrating Trauma
 Esophagus or Trachea
 Vagus nerve disruption
◦ Tachycardia & GI disturbances
 Thyroid & Parathyroid glands
◦ High vascular

25.
 More than 95% of penetrating neck wounds result
from guns and knives, with the remainder resulting
from motor vehicle accidents, household
injuries, industrial accidents, and sporting events
 gun shot wound (GSW) sustain greater injury than
those with stab wounds because of a bullet's ability
to penetrate deeper and cause cavitation, thus
damaging structures lying outside the tract of the
missile.
 Injury to the blood vessels can also result from
external compression or mural contusion.
 Thrombosis is the most common complication of
blood vessel injury, occurring in 25-40% of
patients.

26.
 Blunt trauma to the neck typically results from
motor vehicle crashes but also occurs with sports-
related injuries (eg, clothesline tackle),
strangulation, blows from the fists or feet, and
excessive manipulation
 In motor vehicle crashes, thrusting forward with
the head extended, forcing the anterior neck
against the steering column. Cerebral vessel and
laryngeal injuries secondary to shoulder strap
compression have occurred.
 Direct forces can shear the vasculature producing
shearing damage and resultant thrombosis

27.
 Laryngotracheal Injuries in BNT
 Although not prevalent, it is second to only
intracranial injury as the most common cause of
death among patients with head and neck trauma
and is a clinically important injury.
◦
◦ 60% of all external laryngotracheal traumas are due to
blunt neck trauma.
 The final common pathway of laryngotracheal
injury is compressive force on the larynx leads to
injury. This is modified by the degree of laryngeal
calcification present;

28.
 Dissection of neck
 Before exploring the neck the thorax and the
skuull should be opened and the viscera removed
 After cutting the skin ,the ant cervical strap
muscles are cut and examined
 Expose the thyroid cartilage & trachea
 Following this ,the tongue ,hyoid bone & the larynx
are removed as unit.
 Examine the hyoid bone after separating from
thyroid cartilage & soft tissues removed
 See for periosteal haemorrhages & #
 .Palpate the sup horn of thyroid cartilage .Examine
lamina of thyroid cartilage & cricoid cartilage for
injury.
 Open thyroid cartilage posteriorly & examine
mucosa of larynx

29.
 Triticeous cartilage are little cartilaginous
nodules embedded in the thyroidhyoid
ligsment .These may be confused with a # of
superior horn of thyroid cartilage
 Thank You