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 .
Acute pain after thoracic surgery predicts long-term post-thoracotomy pain.
OBJECTIVE Long-term pain is a common sequela of thoracotomy , occurring in approximately 50 % of patients 2 years after thoracic surgery . Despite this alarming statistic , little is known about the factors responsible for the transition of acute to chronic pain . The aim of the present study is to identify predictors of long-term post-thoracotomy pain . DESIGN Follow-up was for 1.5 years for patients who had participated in a prospect i ve , r and omized , controlled trial of preemptive , multimodal analgesia .  SETTING Subjects were recruited from a tertiary care center . PATIENTS Thirty patients who had undergone lateral thoracotomy  were followed up by telephone , administered a structured interview , and classified according to long-term pain status . MAIN OUTCOME MEASURES Present pain status was measured by a verbal rating scale ( VAS ) . Measures obtained within the first 48 h after surgery were compared between patients with and without pain 1.5 years later . These include VAS pain scores at rest and after movement , McGill Pain Question naire data , patient-controlled morphine consumption ( mg ) , and pain thresholds to pressure applied to a rib contralateral to the thoracotomy incision . RESULTS Fifty-two percent of patients reported long-term pain . Early postoperative pain was the only factor that significantly predicted long-term pain . Pain intensity 24 h after surgery , at rest , and after movement was significantly greater among patients who developed long-term pain compared with pain-free patients . A significant predictive relationship was also found at 24 and 48 h using the McGill Pain Question naire . Cumulative morphine was comparable for the two groups . Pain thresholds to pressure applied to a rib contralateral to the incision did not differ significantly between the groups . CONCLUSION Aggressive management of early postoperative pain may reduce the likelihood of long-term post-thoracotomy pain
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 .