In the lateral position, besides compression of the brachial plexus, which major nerve is at risk?

In the lateral position, particularly during surgical procedures, the major nerve at risk is indeed the peroneal nerve in the 'down' leg. The peroneal nerve, which branches off from the sciatic nerve, is positioned laterally around the fibular head and is susceptible to compression when the leg is positioned inappropriately or when there is excessive pressure from a surgical table or positioning devices.

When a patient is placed in the lateral position, the dependent leg may become compressed against the operating table, especially if it is extended or improperly supported. This compression can lead to traction or pressure injuries to the peroneal nerve, resulting in foot drop or other motor and sensory deficits postoperatively.

While the brachial plexus is a well-known concern in this position, particularly due to the risk of shoulder abduction and neck extension, awareness of the peroneal nerve's vulnerability highlights important positioning considerations to prevent nerve injury.