Which nerve innervates the latissimus dorsi?

The latissimus dorsi muscle is primarily innervated by the thoracodorsal nerve, which is a branch of the brachial plexus that originates from the posterior cord, receiving contributions from the C6, C7, and C8 spinal nerves. This nerve plays a crucial role in the motor supply to the latissimus dorsi, which is essential for its function in shoulder movements such as adduction, extension, and medial rotation.

Understanding the role of the thoracodorsal nerve is important for diagnosing potential nerve injuries or motor deficits related to the latissimus dorsi muscle. This knowledge is particularly relevant in clinical settings and rehabilitation, where assessing shoulder function and strength is vital. Other nerves mentioned, such as the spinal accessory nerve, subscapular nerve, and radial nerve, serve different muscular functions and do not directly innervate the latissimus dorsi. Thus, the thoracodorsal nerve’s specific role in innervation makes it the correct answer.