Birth Injury (*Trauma obstetricum*)

Risk Factors and Etiology

The leading cause of these injuries is mechanical overload. There are several predisposing factors that significantly increase the likelihood of fetal trauma during the perinatal period.

Key risk factors include:

• Size disproportion: Occurs with a contracted maternal pelvis, as well as fetal macrosomia or, conversely, extreme prematurity.
• Gestational age abnormalities: Pronounced prematurity.
• Labor abnormalities: Precipitate or extremely prolonged labor.
• Malpresentation: Various abnormal fetal lies and presentations.
• Obstetric interventions: Injuries can result from manual maneuvers or procedures such as the application of obstetric forceps, internal podalic version, and other manipulations.

Soft Tissue and Cranial Bone Injuries

Head injuries are divided into external (soft tissues and bones) and internal.

Injuries to External Structures:

1. Caput succedaneum: Edema and subcutaneous hemorrhages in the presenting part of the fetus. As a rule, this condition has no serious clinical significance and resolves spontaneously.
2. Cephalohematoma: Accumulation of blood beneath the periosteum of the cranial vault. Its key morphological sign is strict limitation within the boundaries of a single bone (most commonly the parietal bone) because the periosteum is firmly fused with the cranial sutures. In rare cases, cephalohematoma can be complicated by suppuration. It is important to perform differential diagnosis with a skull fracture, which may also be accompanied by subperiosteal hemorrhage.
3. Cranial bone trauma: Rare in modern practice. Includes cracks, fractures, bone depressions, as well as tears and ruptures of sutures (occipital, frontal, parietal).
4. Epidural hemorrhages: Form against the background of fractures and cracks in the cranial vault bones, less commonly due to rupture of the middle meningeal artery.

Intracranial Birth Trauma: The main mechanism is the tearing of dural folds and large veins.

• Tear of the tentorium cerebelli: The most formidable injury, accounting for 90–93% of all fatalities from birth trauma. Most commonly accompanied by massive subdural hemorrhage in the posterior and middle cranial fossae.
• Tears of the falx cerebri and superior cerebral veins are diagnosed much less frequently.

Spine and Spinal Cord Trauma

Spinal and spinal cord pathology during delivery occurs 2–3 times more frequently than intracranial injuries.

• Features of Spinal Injury: Usually manifests as tears or stretches of intervertebral discs, avulsions of vertebral processes and bodies, and fractures. The typical localization of fractures is the C6–C7 region. Morphologically, such injuries are almost always accompanied by massive hemorrhages in the surrounding soft tissues.
• Features of Spinal Cord Injury: Injury to the spinal cord itself is observed even more frequently than trauma to the bony spine framework.
• Pathogenesis: Based not so much on mechanical tearing or crushing of tissues (though possible), but rather on ischemia (impaired blood flow) in the vertebral artery basin. This leads to combined damage to the brainstem, cerebellum, and cervical spinal cord.
• Clinical manifestations depend directly on the level of the lesion:
• Upper cervical segments: Spinal shock or diaphragmatic paresis develops.
• C5–T1 level: Various paralyses and pareses of the upper extremity occur.
• Thoracic region: Characterized by pronounced respiratory disorders.

Peripheral Nerve and Clavicle Injuries

In addition to the central nervous system, peripheral nerve trunks and the shoulder girdle are frequently subjected to mechanical stress.

Peripheral Nerves:

• Facial nerve palsy is often associated with the application of obstetric forceps.
• Brachial plexus palsy occurs with excessive finger pressure on the neck region or excessive traction during fetal extraction.
• Phrenic nerve palsy.

Microscopically, these injuries reveal tissue edema, perineural, and endoneural hemorrhages. Complete mechanical transection of nerve trunks with extensive hematoma formation is rare.

Clavicle Fracture: One of the most common birth injuries. The nature of the damage is usually subperiosteal. The prognosis is favorable: with proper application of a fixing bandage, the bone heals completely by the end of the second week of life.