Assessment and Treatment of Recurrent NTOS

Recurrent neurogenic thoracic outlet syndrome (TOS) is usually caused by scar tissue formation, which re-entraps and compresses the nerves of the brachial plexus. Other causes include missed diagnoses or inadequate surgical procedures. Symptoms and signs of recurrent neurogenic TOS are similar to those that preceded the initial operation. Treatment begins with evaluation for pectoralis minor syndrome. If nerve entrapment is present beneath the pectoralis minor muscle tendon, pectoralis minor tenotomy is an outpatient procedure with minimal risk that may be effective in many patients with recurrent neurogenic TOS. If pectoralis minor syndrome is not present or if pectoralis minor tenotomy has failed, other procedures to consider include (1) supraclavicular scalenectomy, if the previous operation was transaxillary first rib resection; (2) transaxillary first rib resection, if the previous operation was supraclavicular scalenectomy without rib resection; (3) brachial plexus neurolysis, if both supraclavicular scalenectomy and first rib resection have been performed; or (4) in the case of multiple failed operations, combined transaxillary and supraclavicular brachial plexus neurolysis combined with a latissimus dorsi muscle flap.