Erb's Palsy is associated with injury to which cervical nerves?

Erb's Palsy is primarily associated with injury to the upper trunk of the brachial plexus, which mainly involves the fifth and sixth cervical nerves (C5 and C6). This condition typically results from traumatic events such as shoulder dystocia during delivery, where excessive lateral traction on the head can lead to stretching or tearing of the nerves.

These nerves contribute to the innervation of the shoulder and upper arm muscles. Injury to the C5 and C6 nerves can impair functions like shoulder abduction, flexion, and external rotation, as well as elbow flexion, leading to characteristic signs such as the "waiter's tip" posture, where the affected arm hangs by the side and is internally rotated. Therefore, understanding the specific nerve roots involved helps in diagnosing the condition and planning appropriate management and rehabilitation strategies for the affected infants.