Table 2.

Possible mechanisms for perioperative nerve injury [12].

Risk factors	Patient	Anesthetic	Surgical
Preoperative	(i) Preexisting neuropathies (ii) Old age (iii) Chemotherapy (iv) Vascular disease (v) Diabetes mellitus (vi) Multiple sclerosis (vii) Inflammatory or autoimmune disorders
Intraoperative		(i) Needle trauma (ii) Local anesthetic toxicity (iii) Toxicity related to injectate/adjuvants (iv) Hypotension (v) Improper limb positioning (pressure trauma, nerve stretching)	(i) Tourniquet pressure (ii) Direct trauma during surgery (transection, stretch, compression)