Results

Study population

Sixty-one cases of pediatric homicide involving subjects under 1 year of age were found in the studied period. Within this cohort, 39 met the study criteria described above (n = 39). Cases excluded from analysis (n = 22) involved homicides attributed to other causes, including drug toxicity, gunshot wounds, complications of prematurity, hypoxic-ischemic encephalopathy, drowning, and scald injuries.

For age-based analysis, the study population was divided into two groups: neonates (< 1 month, n = 2) and infants (1–12 months, n = 37). The sex distribution consisted of 20 females and 19 males. Racial demographics included 24 African American, 13 Caucasian, and 2 individuals of other racial backgrounds.

A summary of the external and internal findings is provided in Table 1. The findings reported in the table were sometimes observed in isolation and sometimes in combination, coexisting in the same individual.

FINDINGS |  | All (n = 39) | Perc (%)
REMOTE INJURIES
Head external injuries | No | 36 | 92,3
 | Any | 3 | 7,6
Body external injuries | No | 33 | 84,6
 | Yes | 6 | 15,4
Extracranial fractures | No | 26 | 66,7
 | Yes | 13 | 33,3
CRANIAL INJURIES
Scalp external injuries | No | 22 | 56,4
 | Yes | 17 | 43,6
Face external injuries | No | 19 | 48,7
 | Any | 20 | 51,3
Subgaleal hemorrhages | No | 23 | 58,9
 | Yes | 16 | 41,1
Skull fractures | No | 21 | 53,8
 | Yes | 18 | 46,2
Suture diastasis | No | 33 | 84,6
 | Any | 6 | 15,4
EDH | No | 34 | 87,2
 | Yes | 5 | 12,8
Acute SDH | No | 4 | 10,3
 | Yes | 35 | 89,7
Older SDH | No | 32 | 82,1
 | Yes | 7 | 17,9
Overall SDH | No | 34 | 87,2
 | Any | 5 | 12,8
IDH | No | 36 | 92,3
 | Yes | 3 | 7,7
SAH | No | 4 | 10,3
 | Yes | 35 | 89,7
Intracerebral hemorrhage | No | 19 | 48,7
 | Yes | 20 | 51,3
Intracerebral necrosis | No | 27 | 69,2
 | Yes | 12 | 30,8
Global hypoxia ischemia | No | 8 | 20,5
 | Any | 31 | 79,5
Intracerebral findings | No | 27 | 69,2
 | Any | 12 | 30,8
Cerebral hemispheres findings | No | 6 | 15,4
 | Any | 33 | 84,6
Cerebellum findings | No | 20 | 51,3
 | Any | 19 | 48,7
Brainstem findings | No | 25 | 64,1
 | Any | 14 | 35,9
Cerebral edema | No | 15 | 38,5
 | Yes | 24 | 61,5
Diffuse Axonal Injury (DAI) | No | 32 | 82,1
 | Yes | 7 | 17,9
Basal ganglia findings | No | 27 | 69,2
 | Any | 12 | 30,8
SPINAL CORD INJURIES
Cervical spinal cord injuries | No | 23 | 58,9
 | Any | 16 | 41,1
Cervical spinal cord EDH | No | 22 | 56,4
 | Any | 17 | 43,6
Cervical spinal cord SDH | No | 25 | 64,1
 | Any | 14 | 35,9
Cervical spinal cord SAH | No | 34 | 87,2
 | Any | 5 | 12,8
Cervical spinal cord Int hem | No | 33 | 84,6
 | Any | 6 | 15,4
Cervical spinal cord Necrosis | No | 37 | 94,9
 | Any | 2 | 5,1
OCULAR INJURIES
Retinal hemorrhages | No | 5 | 12,8
 | Any | 34 | 87,2
Bilateral retinal hemorrhages | No | 8 | 20,5
 | Yes | 31 | 79,5
Macular fold | No | 38 | 97,4
 | Any | 1 | 2,6
Vitreous hemorrhages | No | 36 | 92,3
 | Any | 3 | 7,7
Bilateral vitreous hemorrhages | No | 37 | 94,9
 | Yes | 2 | 5,1
Optic nerve perineural SDH | No | 6 | 15,4
 | Any | 33 | 84,6
Bilateral optic nerve perineural SDH | No | 7 | 17,9
 | Yes | 32 | 82,1

Remote injuries

Evidence of remote (subacute or healed) extracranial fractures (Fig. 1) was identified in 66.7% of cases (n = 26). Among these, rib fractures were observed in 11 cases, femur fractures in 2, tibia fractures in 2, radius fractures in 2, an ulna fracture in 1, and a vertebral fracture in 1.

Fig. 1: Prevalence of remote injuries observed in the study population (n = 39)

External injuries, including contusions and abrasions, were noted on the head in 7.7% of cases (n = 3) and on the body in 15.4% of cases (n = 6).

Skull and brain pathology

Skull fractures (Fig. 2) were identified in 46.15% of cases (n = 18), most commonly involving the parietal bones, with additional involvement of the occipital and, less frequently, the frontal bones. The majority of fractures exhibited a linear configuration. Several cases demonstrated bilateral fractures, including one instance with bilateral and multiple fractures: one case featured complex fractures of both the left and right parietal bones; another involved bilateral fracture of the occipital and parietal bones extending into the bilateral posterior cranial fossae. Overall, three cases exhibited bilateral fractures, and two cases involved multiple fracture lines.

Fig. 2: Prevalence of “head and skull findings” in the study population (n = 39)

In 15 of the 18 cases with skull fractures, no associated extradural hemorrhage was identified; however, other intracranial injuries were present. Diastasis of the cranial sutures was observed in 15.4% of cases (n = 6).

Brain findings revealed extradural hemorrhages (EDH) in 12.8% of cases (n = 5). Intradural hemorrhage (IDH) was identified in 7.7% of cases (n = 3), with one case described as “focal.”

Subdural hemorrhage (SDH) was the most prevalent intracranial injury, observed in 92.3% of cases (n = 36). Of these, 35 were acute SDH, including 7 cases with bilateral hemispheric involvement. Additionally, 7 cases demonstrated older subdural hemorrhages described as “old,” “organized,” or “organizing,” with six occurring alongside acute SDH and one in isolation.

Subarachnoid hemorrhage (SAH) was present in 35 of 39 cases. All SAHs involved the cerebral convexities; 13 were bilateral, 7 diffuse, and the remainder focal.

Cerebral edema was noted in 61.5% of subjects (n = 24). The most frequent microscopic finding was global hypoxic–ischemic injury, present in 79.5% of cases (n = 31), followed by focal hemorrhages in 51.3% (n = 20) and necrosis in 30.8% (n = 12). Diffuse axonal injury (DAI) was detected in seven cases; however, β-APP (beta-amyloid precursor protein) immunohistochemistry was not routinely performed during the study period.

Brain findings were the most frequently observed (84.6%, n = 33), followed by cerebellar findings (48.7%, n = 19) and brainstem findings (35.9%, n = 14). In addition, histologic examination identified basal ganglia injury in 12 of the 39 cases analyzed (30.8%). Furthermore, autopsy reports documented evidence of intracranial mass effect with bulging fontanelles in 12 of the 39 cases.

Spinal cord neuropathology

Spinal cord injuries were identified in 41% of cases (n = 16) within the cervical region, while 30.8% (n = 12) and 20.5% (n = 8) were in the thoracic and lumbosacral regions respectively. The predominant finding was a thin layer of extradural hemorrhage (EDH), observed in 26 cases involving the cervical spinal cord. Within the cervical spinal cord, additional injuries included 14 cases of subdural hemorrhage (SDH), 5 cases of subarachnoid hemorrhage (SAH), 6 cases of intraparenchymal hemorrhage, and 2 cases demonstrating necrosis.

Ocular pathology

Ocular pathology revealed that retinal hemorrhages and perineural optic nerve subdural hemorrhages (SDH) were frequent findings. Retinal hemorrhages were observed in 87.2% of subjects (n = 34), with 33 cases showing bilateral involvement. Perineural optic nerve SDH was present in 84.6% of cases (n = 33), with 32 exhibiting bilateral distribution. All retinal hemorrhages involved the intraretinal layer. A significant correlation was noted between intracranial subdural hemorrhage and both retinal hemorrhages and perineural optic nerve SDH. Vitreous hemorrhages were less common, identified in 7.7% of cases (n = 3), including two bilateral occurrences. Macular folds were rare, documented in only one case.