Why do we discuss in conjunction skull and cerebral lesions?
Direct impact ACCELERATION: traumatic agent is moving while the head is immobile. Produces an area of depression of the skull Decreases the kinetic energy of the traumatic agent – energy transfer Limited extra space – impact on the brain which does not have an escape route
Direct impact DECELERATION: the head in move stops abruptly when hitting an immobile strong surface. Kinetic energy transmits to the skull and cerebrum Cerebrum continues to move after the skull stops. Secondary trauma to the brain while hitting the bony irregularities: back of orbit and sphenoidal bones (ridge)
Direct trauma BILATERAL COMPRESION: sudden compression with reduction of normal convexity
Direct trauma ROTATIONAL ACCELERATION – complex mechanism where a combination of acceleration and deceleration prdoduces a rotational movement
Indirect trauma Physical force does not action on the head but produces lesions from a distant impact. Although produced by different type of impact, pathogenic mechanisms are similar with those presented for acceleration and deceleration.
Indirect trauma Sudden flexion or extension = produces movements of the skull and cerebrum with different speeds the brain is pushed against the hard skull and is injured. Landing on feet or ischiatic protuberances typical mechanism is that of counter- hit
Clinical examination History: thorough evaluation of the mental status and neurological effects as traumatic effects may determine primary consequences (neurological disturbances, dilacerations), secondary (accumulation of fluids) or late effects (cerebral edema). Time schedule can be very important in judging severity. Evaluation of conscience – a superior form of reflection of the objective world – 90% of head trauma present an impairment of consciousness.
Clinical examination Impairment of consciencesness : Agitation: motor/ psychological - motor Stupor: no tendency to move spontaneously and indifference – conscience status appears to be suspended Obnubilation (difficulties in responding to questions, as if in superficial sleep Mute and akinetic Lack of initiative and less impressed about people around him Confused Coma – partial or total loss of conscience and other function that relate a human being with the environment, chenges in vegetative functions
Definitions are to complex + a lot of subjectivism = confusion in terms GLASGOW Coma Scale International accepted grading for the conscience status 0-8 9-12 13-15
Evaluation of vegetative function Respiration Circulation Thermal homeostasis
Clinical examination Muscular tonus Back of the head Limbs Ability to sustain the forearm or ankle (integrity of the pyramidal pathway) Rigidity by lack of cerebral function(extension of limbs) Rigidity by lack of functional cortex (flexion of limbs) Testing sensibility Evaluation functionality of cranial nerves – in particular for lesions with fracture lines in the base of the skull.
Olfactiv N. (I) Fracture lines involve the fine perforated bonny structure of the etmoid bone, through which the nerve fibers pass inside the skull. The patient if conscientious acuses anosmia impossibility to sense any odor), usually it is unilateral !!!
Optic N (II) Lesions in the middle fossa, between the optic chiasm and the eye – blindness (different areas according to lesion) Concussions may be reversible Section of the nerve is always followed by atrophy and definitive blindness.
Motor nerves of the eye (oculomotor III) Motility disorders with the consequent double vision Ptosis of the eye lid (unilateral) Divergent strabismum Midriasis (unilateral)
Motor nerves of the eye (abducens IV) Palsy of the great oblique muscle with impossibility to look below and outward Double vision depending on the position of the view
Trigeminal (V) Decrease sensibility or anesthesia in the respective cutaneous sensitive areas Motor branch – difficulties in mastication and lateral deviation of the mandible Ophthalmic branch – lack of corneal reflex
Extern oculomotor (VI) Convergent strabismus, with deviation opposite in direction to the normal movement of the nerve
Facial nerve (VII) Facial asymmetry Deviation of the mouth towards the normal side Labial corner lowered on the affected side Eye-bulb on the affected side appears larger Acoustic/vestibular syndrome may be associated when the fracture involves the base of the skull
Acustico-vestibular nerve (VIII) Audition: Abnormal sounds Auditory deficit Vestibular: Only in cases with unaltered conscience the patient may suffer from dizziness or vertigo
Glosopharingeal nerve (IX) Mixt composition motor and sensitive compoents Deglutition problem (palsy of the superior constrictor of the pharynx) Absent pharingeal reflex Hipoestesia or anestesia of the pharynx and posterior third of the tongue
Vagus nerve (X) Palsy of the soft palate Palsy of the recurrent nerve with voice characterized by bitonality Changes in respiration and cardiovascular activity
Spinal (XI) Palsy of sterno-cleido-mastoidian nerve and trapesius. Shoulder is abnormally low and the patient can not move the scapula away from the midline The sterno-cleido-mastoidian on the affected side does not contract when the head is moving.
Hipoglosal nerve (XII) Atrophy of half of the tongue Deviation of the tongue towards the affected side
Cranio-cerebral concussions There is significant difference in terms from soft tissues concussions: in head injuries it is possible the skin to be continuous, but a fracture to produce endocranian infection
1. Concussions of the scalp Particularities: deep fascia slides over the skull (periostum) and as such it is very mobile The scalp is a complex structure that behaves as an entity. It has numerous fibrous structures that produces honey- comb spaces that comprise blood vessels.
1. Concussions of the scalp Haematoma of the skull – may appear during delivery in the skull of babies in the area of presentation of the head. It is a cutaneous bloody suffusion It has a tumor-like appearance which can be deformed while pressing it and will be reabsorbed in days.
1. Concussions of the scalp Subcutaneous hematoma: Direct impact Painful swelling (spontaneous or after manipulation0 Relatively soft (deformable) but may be hard (in tension) If large enough can present a softer area in the middle which can produce “thumb-printing” Specific sound – crepitating – similar when crushing snow in your hand) – poses a risk of confusion with the sound of moving bony fragments It develops under the deep fascia and can migrate in adjacent area
1. Concussions of the scalp Subperiostal hematoma Blood suffusion developing between the external layer of the bone and the periosteum after the rupture of epicranial vessels Develops typically after a difficult delivery or forceps application Most frequent in the parietal region It is a round or oval structure with central liquefaction It may transform in bony structures
2. Concussions of the skull Fractures produced at the impact area or distant fractures radiated from the impact area Fractures can be: Localized Radiating towards the base of the skull Fractures Incomplete (only one of the bony layers) Complete (both layers)
2. Concussions of the skull Fractures - simple or multiple Fractures - with detached fragments With or without protrusion inside the skull cavity With or without lesions of the cerebrum
Fractures of the base of the skull Resistance arches that are continuous with those on the skull cap Transmit forces away from impact zone
Frontal impact Radiation of the fracture towards the anterior or middle foosa of the base Major risks : orbital cavity, optical nerve, oculomotor and abducens.
Temporal impact Can radiate in any segment of the base Frequently fractures of the petrous portion Can produce lesions in the inner ear
Occipital impact Risk to radiate toward the middle and anterior fossa of the base
Simptomatology Many do not present any symptoms Epistaxis Periorbital hematoma Bilateral subconjunctival hemorrhage Hemorrhage exteriorised through the ear Perimastoidian hematoma Hematoma developing in the posterior pharingeal subbmucoasa Licvoreea (cerebrospinal fluid)
Epistaxis Suggest a fracture of the anterior fossa Etmoid fracture + vessel disruption Careful to exclude other possible diagnosis
Bilateral periorbital hematoma Unilateral is rare and is typical produced by direct impact Bilateral: blood originates in the anterior or middle fossa and migrates towards the orbit and periorbital tissues. Characteristic for base pf the skull fractures
Bleeding from the ear Highly suggestive for base of skull fracture Middle fossa Originates in timpanic vessels, middle ear or vessels around petrous portion of the temporal bone. Fracture of the petrous portion should be made after excluding other entities (open fracture)
Otorahia and retro/perimastoidian hematoma Middle fossa fractures The typical afected vessel is the mastoidian vein
Licvoreea (loss cerebrospinal fluid) Cristal clear liquid Exteriorization in many alternatives It reveals a fracture of the base of the skull (or a panetrating injury) Loss of fluid can be continuous or discontinuous) OPEN FRACTURE