CT findings of atrophy of chest wall muscle after thoracotomy: relationship between muscles involved and type of surgery.

OBJECTIVE

Postthoracotomy atrophy of chest wall muscles results from nerve injury during surgery. After encountering patients with different patterns of chest wall muscular atrophy postthoracotomy, we performed this study to determine the relationship between type of thoracotomy and atrophic muscles as seen on CT scans.

MATERIALS AND METHODS

CT scans of 58 patients who had previously undergone unilateral thoracotomy were reviewed. Forty patients had a posterolateral thoracotomy, and 18 had an anterolateral thoracotomy. In two cases, the incision extended posteriorly. Atrophy seen on CT scans was defined as a marked decrease in size or thickness of a muscle compared with the muscle on the other side.

RESULTS

Atrophy of the latissimus dorsi muscle and of the inferior portion of the serratus anterior muscle was detected on CT scans in 40 patients. No atrophy was found in 16 patients. The remaining two displayed atrophy only in the serratus anterior muscle. Atrophy of the latissimus dorsi muscle and of the inferior portion of the serratus anterior muscle developed in all patients who had a posterolateral thoracotomy. Atrophy developed in only two of the 18 patients who had an anterolateral thoracotomy, and in these two, the incision had been extended posteriorly.

CONCLUSION

A direct correlation was found between type of thoracotomy and site of atrophy of the chest wall muscles seen on CT scans. This finding may account for different CT appearances of the thoracic wall in patients who have had thoracic surgery.