Fractures

Skull Fractures:

The classic interpretation of infantile skull fractures is that anything but a non-widely spaced simple linear fracture of the parietal bone is due to non-accidental injury (Kravitz, et. al.). Such fractures would include depressed, stellate, comminuted or other complex types of skull fractures. Many believe that falls less than 3 feet only rarely produce any kind of skull fracture and skull fractures only occur when extremely violent forces are brought to bear on the infant. Others (Weber, Plunkett) have demonstrated that simple as well as complex fractures of the skull can occur from "short" falls. Skull fractures do not necessarily cause signs or symptoms, and may not be associated with underlying dural or brain injury (Shutzman and Greenes). Very young infants (<6 months) may have major cranial deformation due to an impact but no skull fracture, because their skulls are malleable and elastic, whereas older children have more rigid adult-like ossified skulls and are more vulnerable to skull fractures. However, the fracture threshold for an infant is approximately 10% that of a child or adult (Goldsmith - personal communication, Marguiles and Thibault). A special pattern of bilateral skull fracture can occur when crushing forces occur against the infant skull. Skull fractures cannot occur without impact of the head against a rigid object. They cannot occur with shaking.

Skull fractures are caused by a deformation of the skull due to impact of some kind. The likelihood that a child will suffer a skull fracture depends on the force, location of the impact, age of the child, and biologic/mechanic characteristics/properties of the skull at the point of impact. Children with open sutures and more flexible skulls are not as likely to fracture in short falls as are older children with fully developed enclosed skulls.

Simple Linear Fractures: Fractures that follow one linear pattern.

Multiple Fractures, Complex Fractures or Fractures: These fractures are said to require a greater degree of force. Skull Fractures from a fall to a flat surface generally show an impact site with one or several fracture lines radiating from the point of impact whereas falls to raised surfaces, or blunt impact with an object can show depressed fractures.

Depressed Fractures or Fractures with a "Punch Out" Fractures in which bone fragments are pushed inward (looks like a hole punched out). Generally thought to be seen when a person falls on a sharp corner or on a flat surface with a raised object on it (rock on a tile floor or barrett on a child's head). Also seen with blunt force trauma (hammer to the head) or missile trauma (gunshot wound). However, a depressed fracture may be found with an impact to a flat surface.

Compound Depressed Fractures: Fractures with multiple lines and a larger bone fragments depressed inward from the skull cavity. Generally seen with blunt force trauma and falls to surfaces with raised edges or objects. These generally require medical intervention and/or surgery to prevent serious brain damage or disorder.

Temporal Bone Fractures:
Longitudinal: Front to back skull fractures of the skull thought to be caused by blunt force trauma to the head around the face, frontal or occipital regions. Can also be caused by compression of the head from front to back.

Transverse Fracture: Side to side fractures of the skull caused by impact or compression to the sides of the head.

Skeletal Fractures

Rib Fractures: Rib fractures in children are generally thought to be the result of some mechanism of compression to the chest cavity. Rib Fractures are said to be "Classic Indicators" of Shaken Baby Syndrome. However, less than 10% of the cases charged as SBS show evidence of rib fractures. The issue of rib fractures in infants who have received CPR (especially by untrained hands) has not been thoroughly explored.

Metaphaseal Fractures: Fractures of the long bones (arms and legs) caused by twisting, pulling, jerking or wringing of a child's arms or legs. Most often found in children under 1 year old. These fractures are said to be suspicious of child abuse.

Osteogenisis Imperfecta or "Brittle Bone Disease": Genetic disease seen mostly in newborn babies and children caused by a collagen disorder which causes kids to have increased susceptibility to fractures. True OI is a permanent condition is based on a faulty type or lack of collagen in the bones but fractures generally decrease after hormonal changes in adulthood.