Because...
The nerve suturing technique they wanted to learn a while ago is difficult for them to master.
After all, this kind of technique isn't something that can be learned in a short while.
But now, the surgical plan is different.
The surgical plan is fully referential.
A brachial plexus injury isn't just limited to the arm area.
The patient has suffered an avulsion injury of the brachial plexus roots, meaning there's severe trauma to the patient's neck and chest areas.
Although it's just external trauma, and doesn't affect internal organs...
Still, this increases the difficulty of the surgery.
Because at this time, the patient's cervical plexus, accessory nerve, and intercostal nerves can't be utilized.
It's just like blood vessel reconstruction.
The reconstruction of nerve function also requires materials.
And the readily available cervical plexus, accessory nerve, and intercostal nerves are all good materials.
They can be "borrowed" during surgery.