Differential Diagnosis for Asymmetrical Movement of the Left Upper Extremity in a Newborn
Single Most Likely Diagnosis
- Brachial Plexus Injury: This condition is often associated with asymmetrical movement of an upper extremity in a newborn. The presence of clavicular crepitus suggests a fracture, which can occur during a difficult delivery, especially in macrosomic infants. A brachial plexus injury can happen when the nerves are stretched or torn, typically during a shoulder dystocia.
Other Likely Diagnoses
- Clavicle Fracture: Directly related to the clavicular crepitus mentioned, this is a common birth injury, especially in larger babies or during difficult deliveries. It can cause pain and asymmetrical movement due to discomfort.
- Erb's Palsy: A form of brachial plexus injury affecting the upper arm, it results from damage to the nerves that control the muscles of the upper arm, leading to weakness or paralysis. It's a common birth injury, often associated with macrosomia and difficult deliveries.
Do Not Miss Diagnoses
- Osteogenesis Imperfecta: A genetic disorder that affects the production of collagen, leading to fragile bones. While rare, it's crucial to consider because it can cause fractures (including clavicular) with minimal trauma and has significant implications for the infant's health and management.
- Infection (e.g., Group B Strep): Although less directly related to the asymmetrical movement and clavicular crepitus, infections can cause a wide range of symptoms in newborns, including irritability, lethargy, and poor movement. In severe cases, they can lead to conditions like osteomyelitis or septic arthritis, which could affect limb movement.
Rare Diagnoses
- Cranial Nerve Disorder: While cranial nerve issues can affect movement, they are less likely to present with such localized signs as asymmetrical upper extremity movement and clavicular crepitus in a newborn.
- Vitamin D Deficiency in the Birthing Parent: Maternal vitamin D deficiency can affect fetal bone health, potentially leading to conditions like rickets. However, this would be less likely to cause acute, asymmetrical movement issues and clavicular crepitus at birth.
- Birth Trauma due to Other Causes: Other rare causes of birth trauma, such as forceps injury, could potentially lead to similar symptoms but are less common with modern obstetric practices.