However , intercostal nerve injury seems to be the most important pathogenic factor .
Chronic pain complaints after thoracic surgery represent a significant clinical problem in 25 - 60 % of patients .
Results from thoracic and other surgical procedures suggest multiple pathogenic mechanisms that include pre- , intra- , and postoperative factors .
This review attempts to analyse the methodology and systematic s of the studies on the  post-thoracotomy pain syndrome ( PTPS ) after lung cancer surgery in adults , in order to clarify the relative role of possible pathogenic factors and to define future strategies for prevention .
A prospective, double-blinded, randomized trial evaluating the use of preemptive analgesia of the skin before thoracotomy.
BACKGROUND Thoracic surgeons spend a lot of time treating the pain of thoracotomy . METHODS A total of 119 consecutive patients underwent elective thoracotomy .  They were prospect ively r and omized into two groups . One group received an injection of 1 % lidocaine with epinephrine in the planned skin incision just before thoracotomy , and the other group received an equal amount of saline and epinephrine . All patients had a functioning preoperative epidural ; a skin incision the width of their latissimus dorsi muscle , which was cut ; sparing of the serratus anterior muscle ; undercutting of the sixth rib ; intercostal nerve blocks before rib spreading ; a similar number of chest tubes and pulmonary resections ; and comparable postoperative pain management . Pain was objectified by a numeric pain score , a visual pain score , and by the Modified McGill pain question naire each day in the hospital , and at 3 , 6 , and 12 months postoperatively . RESULTS There were 66 patients in the lidocaine group ( L group ) and 53 patients in the saline group ( S group ) . Although a trend was noted toward less pain in the L group during the first 3 postoperative days ( on the numeric pain scale only ) the difference was not statistically significant in overall pain in the hospital or at 3 , 6 , and 12 months after the operation . Other pain scores and descriptors were similar throughout . CONCLUSIONS The injection of lidocaine and epinephrine in the skin just before thoracotomy does not decrease the amount or type of pain during the hospital stay or at 3 , 6 , and 12 months after surgery
However , intercostal nerve injury seems to be the most important pathogenic factor .
Chronic pain complaints after thoracic surgery represent a significant clinical problem in 25 - 60 % of patients .
Results from thoracic and other surgical procedures suggest multiple pathogenic mechanisms that include pre- , intra- , and postoperative factors .
This review attempts to analyse the methodology and systematic s of the studies on the  post-thoracotomy pain syndrome ( PTPS ) after lung cancer surgery in adults , in order to clarify the relative role of possible pathogenic factors and to define future strategies for prevention .