Radiological examinations can be utilized to evaluate whether findings have a significant association with abuse. The table below identifies which injuries have a high specificity for abuse.
Diaphyseal fractures are common accidental injuries. No type of diaphyseal fracture is diagnostic of abuse. For more information, see
Common Types of Diaphyseal Fractures Seen in Childhood, Appendix F.
The Specificity of Radiological Findings and Abuse
High specificity
Classic metaphyseal lesions
Rib fractures, especially posterior
Scapular fractures
Spinous process fractures
Sternal fractures
Any infant with an unexplained fracture
Moderate specificity
Multiple fractures, especially bilateral
Fractures of different ages
Epiphyseal separations
Vertebral body fractures and subluxations
Digital fractures
Complex skull fractures
Common but low specificity
Subperiosteal new bone formation
Clavicular fractures
Long bone shaft fractures
Linear skull fractures
Evaluating for Previous Injuries
In addition to evaluating acute injury, radiological examinations can evaluate for previous injuries. The table below outlines stages of bone injury healing.
Stages of Bone Injury Healing
Stage
Time
Characteristics
Induction
3-7 days
Inflammation, pain swelling
Soft tissue swelling
Soft callus stage
- 7-10 days for infants
- 10-14 days for older children
- Periosteal new bone formation
- With instability or repetition of injury this stage may persist with new bone formation (days 4-10) and callus formation (days 10-14) around the fracture site
Hard callus stage
- Begins at days 14-21
- Peaks at days 21-42 in infants
Union at the fracture site
Remodeling
3 months - 1 year
Woven bone converted to lamellar bone with restoration of original configuration of bone
Reference: Reece, R. What the literature tells us about rib fracture in infancy. National Conference on SBS. SBS Quarterly. Fall 2002.
Skeletal Survey
When abuse is suspected, use a skeletal survey to look for signs of previous or acute injuries. The survey consists of dedicated images of every anatomic region. It includes anteroposterior and lateral images of the axial skeleton and frontal projections of each extremity. Take additional views of definite or possible fractures. View abnormalities in at least two projections. Take oblique views of the thorax if rib fractures are suspected. Order four views of the skull if head trauma is suspected. There are variations on the protocol for a complete skeletal survey. The table below outlines the recommended survey from the American Academy of Pediatrics.
A follow-up skeletal survey, without skull films, is sometimes recommended at 10-14 days because of the lag time for healing bone injuries. This is particularly true for rib fractures because there is rarely significant displacement, and the fracture is less evident until there is callus formation.
The American College of Radiology has published the technical guidelines for a skeletal survey.
Complete Skeletal Survey
Appendicular Skeleton
Humeri (AP)
Forearms (AP)
Hands (Oblique and PA)
Femurs (AP)
Lower Legs (AP)
Feet (AP)
Axial Skeleton
Thorax (AP and lateral), to include thoracic spine and ribs
Abdomen, lumbosacral spine, and bony pelvis (AP)
Lumbar spine (lateral)
Cervical Spine (lateral)
Skull (frontal and lateral)
AP = anteroposterior; PA = posteroanterior
Age-Based Recommendations
The application of radiological studies is recommended as follows:
0 to 12 months
Skeletal survey
Scintigraphy (bone scan) may be added in selected cases
Follow-up skeletal survey in two weeks for strong suspicion of abuse or to better delineate findings discovered on initial examination
12 months to 2 years
Skeletal survey or scintigraphy with any positive areas evaluated with radiographs
If scintigraphy is used, skull x-rays must still be done because of the insensitivity of scintigraphy to detect cranial injuries
2 to 5 years
Skeletal survey or scintigraphy in cases where abuse is strongly suspected
Standard radiographs of any area with significant clinical findings
Follow up skeletal survey in two weeks for strong suspicion of abuse or to better delineate findings discovered on initial examination
5 years and older
Radiographs based on clinical findings
Note: Age-based recommendations may need to be adjusted when there is developmental delay.
Technique Recommendations Scintigraphy
In general, bone scans are used to complement information gained in the skeletal survey.
May be used as an alternative to a skeletal survey in children older than two years.
Data support increased sensitivity detecting rib fractures, subtle shaft fractures, and areas of early subperiosteal new bone formation.
Not well supported for evaluation of the classic metaphyseal lesions of abuse or of subtle spinal lesions, which also have a high specificity for abuse.
Sonography
Via the anterior fontanelle in young children to help assess the potential long- and short-term consequences of inflicted head injury.
Should be performed in conjunction with CT or MRI and not as the sole method of imaging.
MRI/CT
MRI offers the most complete soft tissue image of the brain.
MRI is best to evaluate for sub-acute or chronic injury.
Use CT to determine acute blood accumulation or need for immediate surgical intervention.
CT demonstrates scalp swelling that may not be present clinically, as well as complex or depressed skull fractures.
The American College of Radiology suggests obtaining a head CT in addition to a skeletal survey in children with suspected abuse and an altered mental status.
Consider a head CT for very young infants because the neurological examination is less likely to provide insight regarding possible injury.
