anatomy of neck and its medicolegal importance

1. Nafeeya
1st yr pg
Anatomy Of Neck And Its
Medicolegal Importance

2. Overview
 Anatomy and its relations
 Glands of neck and its functions
 Hyoid bone
 Neck dissection
 Injuries of neck
 Medicolegal importance

3. Compartments
 Content of neck is grouped into neck
spaces called the compartments
 Vertebral compartments-cervical
vertebrae and postural muscles.
 Visceral compartments-glands[thyroid
,parathyroid and thymus],larynx ,pharynx
and trachea.
 Vascular compartments-common
carotid artery ,jugular vein ,and vagus
nerve on either side.
 Each compartments is enclosed by
musculofacial collar.

4. Vertebral Compartment
 Long flexible part
 It consist of 7 bones
 C1-C7
 Intervertebral disc

5. Muscles Of The Neck

6. Triangles Of Neck

7. Posterior Triangle Of Neck

8. Vasculature Of Neck

9. Nerve Supply Of Neck
 The
Cranial Nerves mainly
supplying neck are
 The Facial [VII],
 Glossopharyngeal [IX],
 Vagus [X],
 Accessory [XI], And
 Hypoglossal [XII] Nerves.
 Transverse Cervical Nerve
 Supraclavicular Nerve

10. Anatomy Of Thyroid Gland
 15-25gm
 Butterfly
 2 Lobes
 2 Capsule
 Isthmus Extends Across Midline
In Front Of 2 ,3
4th Tracheal Ring.
 Located Deep To Sternothyroid
and Sternohyoid
 Functions-metabolism
Growth,development.
 Regulates Body Function

11. Hyoid Bone
 U- shaped structure
 Located in the anterior neck.
 It lies at the base of the mandible (approximately c3)
 It acts as a site of attachment for the anterior neck muscles.
 The hyoid is ossified from 6 centers: two for the body, and one for
each cornu.
 The cartilage of the third pharyngeal arch forms the greater cornu
of the hyoid and the lower portion of the body of the hyoid.
 Ossification commences in the greater cornua toward the end of
fetal development. [3rd trimester]
 In the lesser cornua during the first or second year after birth.
 Elderly -calcified

12. Tension
Required
 TO OCCLUDE
VARIOUS
STRUCTURES IN THE
NECK:
 JUGULAR VEIN -2 KG
 CAROTID ARTERIES -5
KG
 TRACHEA -15 KG
 VERTEBRAL
ARTERIES -20 KG

13. Autopsy Neck Dissection

14. V-Shaped neck incision
Platysma and subcutaneous
tissue dissection.
Deep cervical fascia is
incised and reflected

15. Sternocleidomastoid
dissected & reflected
on each side
Omohyoid
,sternohyoid,thyrohy
oid reflected on
each side
Thyroid and carotid
sheath are freed from
investing layer
Larynx ,trachea,pharynx and
oesophagus are pulled away
from prevertebral tissue.

16. Larynx And Trachea
 Cartilagenous , ligamentous
 Below - hyoid
 Above -trachea .
 3-6 cervical vertebrae
 4-6 brachial arches
 Facilitates breathing and sound
 MC-triticeal cartilage [30%]

17. Injuries Of Neck

18. Injuries Of Thyroid Gland
 Complicated thyroidectomy surgery
 Recurrent laryngeal injury
 Branch of vagus nerve
 Unilateral injury-vocal cord motion
-Less-voice weak and motionless
 Bilateral injury-incomplete and complete
 Leads to adduction of cord and suffocation
 Complete-leads to aphonia
 Tetany

19. Zones Of Neck

20. Injuries Over The Region Of
Neck
1.Homicidal
o Strangulation- ligature or manual
o Throttling or manual strangulation
o Bansdola
o Garrotting
o Mugging
2.Penetrating Injuries-knife Or Gunshot
3.Cut Throat Injury
4.Injuries above level of C4- rapid death
o Atlanto occipital injury-fatal
o C1-C2-injury-neurogenic shock ,Odontoin#
o C2-C3-Hangman #
2.Suicidal
• Hanging[mc]
3.Judicial hanging
4.Accidental
 Hanging ?
 Chocking
 Café coranary
 Traumatic asphyxia
 Postural asphyxia

21. Hanging Ligature Strangulation
Ligature mark –oblique
Does not encircle the neck completely
Below chin and above thyroid cartilage
Base-pale ,hard and parchment like
Ligature mark-transverse
Encircle the neck completely
At or below thyroid cartilage
Base-soft and reddish
Brushing of neck muscles not common Brushing of neck muscles common
Neck streched and elongated Not so
Hyoid bone fracture may occur Uncommon –[manual-common]
Thyroid cartilage fracture –less
common
Thyroid cartilage fracture- more
common
Carotid intimal tear seen rare
Salivary dribbling present absent
Bleeding -uncommon common
Subconjuctival hemorrhage- absent present

22. PM Findings Of Hanging In The
Neck
 Petechiae-Tardieu spot
 Le facies sympathique
 Salivary dribbling
 Ligature mark
 Tissue under ligature mark are
dry ,pale,and glistening
 Thyroid cartilage fracture
 Hyoid bone fracture

23. Blunt Force Impact
 Blunt force impact to the side of neck-excessive rotation or
hyperextension
1. Shearing of neck muscle
2. Tearing of vertebral artery
3. Carotids get dissected
4. Veins damaged
5. Sub arachnoid hemorrhage.
 Blunt force impact on anterior neck
1. Crush injury larynx and trachea
2. Compression of esophagus against
spinal column
3. Sudden increased in intratracheal
pressure against closed glottis
4. Crush bruise
5. Rapid acceleration/deceleration-
tracheal injury

24. Sections
 Sec299-culpable homicide not amounting to
murder
 Sec 304-[life imprisonment with fine]
 Sec300-culpable homicide amounting to murder
 Sec 302-[capital punishment or life imprisonment
with fine]
 Sec305-abetment of suicide of child or insane
 Sec 306-abetment of suicide[1-10yrs +fine]
 Sec 307-attempt to murder[1-10yrs with fine]
 Sec 308-attempt to commit culpable homicide[1-
3yrs+fine]

25. Referrences
 Bd chaurasias human anatomy vol-3
 Richard and snells textbook of anatomy
 Guyton and hall text book of physiology
 Narayana reddy essential of forensic medicine
 Anil agarwal textbook of forensic medicine
 Rajesh bardalae textbook of forensic medicine
 Colour atlas of charles castanese
 Brendan c stalk neck dissection
 Essential of anatomy and physiology valarie c
scanlon