• thoracic outlet syndrome
• complex regional pain syndrome
• pain

We read with interest the article by Casey et al.¹ Notwithstanding their substantial work, we have a few comments about their article. First of all, we wonder whether they performed any evaluations for coagulopathy in such a patient with severe thrombosis and endothelial damage. We also wonder why they delayed surgery for one month, whether they prescribed an exercise programme before prophylactic left cervical rib excision was planned, if the patient initially had any neurological findings, such as muscle weakness, atrophy, hypoaesthesia, or reflex abnormalities, or any objective evidence of neurogenic thoracic outlet syndrome (TOS). As the patient was diagnosed with TOS and it is generally recommended that first rib resection and scalenectomy be performed for this condition, why these were not applied is not clear from the text.

The main point that we would like to stress is the mechanism of the patient’s pain relief after sympathectomy. Do the authors believe that it was due to improved circulation, which we believe is unlikely in such occluded vessels, and could it have been confirmed by imaging? We believe that some of the painful symptoms may have been due to complex regional pain syndrome, a likely diagnosis in patients with TOS, in whom the sympathetic fibres around the subclavian artery, innervating the upper extremities, become compressed by a cervical rib. The patient’s good symptomatic relief despite some arm claudication after surgery also supports our hypothesis. Thus we propose that the favourable outcome after sympathectomy may rather have stemmed from its beneficial effects on complex regional pain syndrome.