Ihave a daugh­ter.  She just turned two.  She is the love of my life.  She is cute and pre­cious and just absolutely lov­able.  I can­not imag­ine what it would be like if she were to die at any age, but espe­cially at this age or younger.  I really could not imag­ine if I or some­one else were accused of killing her by way of Shaken Baby Syn­drome (“SBS”).  With­out a doubt there are very few top­ics that bring out more under­stand­able pas­sion than child abuse or the death of a child.  The fact finder, whether it is a Judge or a Jury, does not have the lux­ury of pas­sion, but is sworn to exam­ine the evi­dence crit­i­cally, with skep­ti­cism and analytically.
Shaken Baby Syndrome. Is it a valid diagnosis?
Shaken Baby Syn­drome. Is it a valid diagnosis?
The typ­i­cal case involves an infant, one year old or less, who is seen with res­pi­ra­tory dis­tress at the home, then sent to the hos­pi­tal.  The pre­sen­ta­tion is typ­i­cally remark­able with notes of sub­dural hem­or­rhages with reti­nal bleed­ing, no exter­nal trauma and no report of a note­wor­thy fall.
First let’s talk about the cur­rent prosecution-oriented myths that sur­round Shaken Baby Syn­drome.  Then, we will employ basic and valid bio­me­chan­ics and gen­er­ally accepted prin­ci­ples of anthro­pom­e­try to real­ity in order to expose these myths.
Well first, let’s take a look at the “loaded lan­guage” inher­ent in the diag­no­sis.  It is called Shaken Baby Syn­drome, which evokes quite a bit of emo­tion based sim­ply upon its title.  How­ever, it is now being reframed as Shaken Baby Impact Syn­drome, Non-Accidental Injury Syn­drome, and Infant Brain Injury Syn­drome to exac­er­bate the cog­ni­tive prej­u­di­cial effect of it all.
Anatomical Areas of Concerns in SBS
Anatom­i­cal Areas of Con­cerns in SBS
There are sev­eral basic myths that under­score and char­ac­ter­ize the situation.
The diag­no­sis is truly a clin­i­cal one and not one that is born of any mea­sure of mean­ing­ful empir­i­cal test­ing. The notion that the triad or con­stel­la­tion of injuries together can only man­i­fest based upon vio­lent shak­ing that is inten­tional to the exclu­sion of every­thing else leads to the poten­tial of extreme mistakes.
  1. Doc­tors who seek to diag­no­sis SBS look at sev­eral presentation-symptoms dur­ing a phys­i­cal exam­ine to include:
    1. sub­arach­noid hem­or­rhage.  (Arach­noid hem­or­rhage is blood beneath the arach­noid area of the brain.  The bridg­ing vein con­nects the dural sinus to the cor­ti­cal sur­face of the brain);
    2. sub­dural hematoma.  (A sub­dural hematoma is diag­nosed when there is bleed­ing between the dural cov­er­ing of the brain into the poten­tial space which usu­ally has no bleed­ing there);
    3. pat­e­chial reti­nal hemorrhaging;
    4. hypoxia;
    5. the lack of lucid inter­val between alleged shak­ing and treat­ment or examination;
    6. whether or not the care­giver posits a rea­son­able expla­na­tion accord­ing to the treat­ing physi­cian to account for all of this.  In other words, does the exam­in­ing physi­cian believe the caregiver’s explaina­tion for how the dam­age was sustained?
    7. The sec­ond myth is that the symp­to­mol­ogy can­not present itself from a short dis­tance fall of two to three feet.
Accord­ing to the pros­e­cu­tion, it is the rota­tional accel­er­a­tion of the cra­nium that rup­tures these bridg­ing veins and causes sub­dural hematoma or sub­arach­noid bleed­ing and the reti­nal bleeding.
Now let’s speak the truth.  Is it true that after a short dis­tance fall that presents with no out­ward trauma that there can never be a sub­dural hematoma or sub­arach­noid bleed­ing and the reti­nal bleed­ing with no lucid interval?
Well, no.
The best exam­ple of the lucid inter­val between a short dis­tance fall with sub­dural hematoma or sub­arach­noid bleed­ing and the reti­nal bleed­ing with no out­ward trauma was the case of Natasha Richard­son.  The untimely and unfor­tu­nate death of the famous actress occurred when she was on the “bunny hill” dur­ing a very short fall at very low impact result­ing in no out­ward trauma.  She remained lucid for quite a while after­wards and then died.
Now let’s use basic anthro­pom­e­try and basic bio­me­chan­ics to exam­ine whether or not shak­ing a baby to cause enough rota­tional injury result­ing in these injuries is indeed even pos­si­ble with­out result­ing in out­ward trauma?
12 month old CRABI
12 month old CRABI
Well, again, the answer is no.
The most telling phys­i­cal real­i­ties that con­fronts Shaken Baby Syn­drome and reveals it as an unproven belief or at worst a dan­ger­ous myth occurs when one sci­en­tif­i­cally exam­ines this notion that the only expla­na­tion when there is a sub­dural hematoma or sub­arach­noid bleed­ing and the reti­nal bleed­ing with­out out­ward obvi­ous trauma is SBS.  There can, in fact, be sub­dural hematomas or sub­arach­noid bleed­ing and reti­nal bleed­ing with­out out­ward obvi­ous trauma other than from SBS.
In order to prove this is not unique to SBS or to estab­lish that SBS is indeed impos­si­ble with­out out­ward trauma, we must first know that sci­en­tif­i­cally there are gen­er­ally two dif­fer­ent types of force:  lin­ear force and trans­la­tional force.  The for­mer is a mea­sure of accel­er­a­tion that always acts in a par­tic­u­lar direc­tion, such as grav­ity.  The lat­ter is a mea­sure of accel­er­a­tion based upon a rota­tion.  In order for there to be suf­fi­cient rota­tional iner­tia to cause the intracra­nial injuries in an infant, accord­ing to pro­po­nents of Shaken Baby Syn­drome, there must be between 6000 to 7000 radi­ans per sec­ond squared of rota­tional accel­er­a­tion exerted on the cra­nial cavity.
A peer-reviewed study per­formed on Penn State Divi­sion One foot­ball play­ers dis­pels this as a real pos­si­bil­ity.  They were given a CRABI device[i] and asked to shake the device as vio­lently as pos­si­ble with the stated aim for these well-trained ath­letes to cre­ate as much rota­tional force as pos­si­ble.  At their best, they could only gen­er­ate approx­i­mately 1500 radi­ans per sec­ond squared.  How­ever, when they were asked to slam the child’s head against a hard object, like a floor, they could gen­er­ate 50,000 radi­ans per sec­ond squared.  As the researcher noted with this mod­i­fied method of slam­ming the child’s head against the floor, an exam­in­ing physi­cian would see signs of exter­nal trauma. This is basi­cally what we would expect to see if the impulse (J) was low.  (J = FΔt;  as t (decel­er­a­tion) gets smaller, the J value drops sig­nif­i­cantly even when pre­sented with the same force.  Small J means the change in momen­tum is very fast, which is obvi­ously going to have phys­i­cal ram­i­fi­ca­tions.  When the exper­i­ment was mod­i­fied to include a short dis­tance fall, suf­fi­cient radi­ans per sec­ond squared were created.
12 month old Crabi in short fall
12 month old Crabi in short fall
Fur­ther the study found that in order for the foot­ball play­ers to gen­er­ate the approx­i­mate 1500 radi­ans per sec­ond squared, the play­ers instinc­tively held on to the rib area so strongly that it would very likely cause bro­ken or bruised ribs and/pr a long bone frac­ture for exam­ple in the arm or leg.
Addi­tion­ally from the world of bio­me­chan­ics and anthro­pom­e­try we learn that in an infant the head is a dis­pro­por­tion­ately large amount of mass as com­pared to a human with mas­sively under­de­vel­oped neck mus­cu­la­ture to sup­port its weight or ori­en­ta­tion.  This is why we are all taught to hold a baby’s head when pick­ing it up or the head will flop caus­ing injury to the neck.  Such is the case with SBS.  If it is an alleged SBS sit­u­a­tion, the del­i­cate area of a baby’s neck would defin­i­tively present to the exam­in­ing physi­cian with unmis­tak­able signs of trauma.
Addi­tion­ally, if there is a lack neck injury then there is also less then demon­stra­ble evi­dence of Shaken Baby Syn­drome as the head and the mus­cu­la­ture around the neck of an infant is the most vul­ner­a­ble area involved with babies.
The neck is the most vulnerable area in an infant and will break first before SBS occurs
The neck is the most vul­ner­a­ble area in an infant and will break first before SBS occurs
Other myths that are eas­ily demys­ti­fied include:
  • reti­nal hem­or­rhag­ing is exclu­sive to abuse  (N.B., The true mech­a­nism that causes reti­nal hem­or­rhag­ing is not known)
  • sub­dural hematomas are a pre­sen­ta­tion of shaking
  • reti­nal bleed­ing is diag­nos­tic of abuse
  • it is impos­si­ble to have a period of lucid­ity afterwards
  • chronic sub­dural hematomas never re-bleed, mean­ing if there is a pre­ex­ist­ing injury then it always heals and it is never sub­ject to re-presentation (N.B., sub­dural hematomas can­not be dated)
[i] The Child Restraint/Air Bag Inter­ac­tion (CRABI) dummy has been devel­oped at First Tech­nol­ogy Sys­tems, Inc. (FTSS) to eval­u­ate small child restraint Sys­tems in auto­mo­tive crash envi­ron­ments, in all direc­tions of impact, with or with­out air bag inter­ac­tion.  There are three sizes of infant dum­mies: a 6-month-old, 12-month-old, and 18-month old.  Accelerom­e­ters are used to mea­sure head, chest accel­er­a­tion and head angu­lar acceleration.