A few comments-
The poster had swelling in the arm but no clot in the thoracic outlet on the first ultrasound. They also later developed a blood clot in the other arm. Makes me think either they have a blood clotting disorder, or a structural issue downstream from the thoracic outlet.
The blood clot likely extended proximally, towards the heart, so that the second ultrasound found it. But as to the clot originating in the thoracic outlet, we should question that suggestion.
I have never seen a case of vein compression or of venous TOS caused by a cervical rib. Specifically, the cervical rib is too far posterior to affect the subclavian vein. Look at the image for explanation. There are other anatomic structures that can compress the subclavian vein, but they are in the anterior part of the thoracic outlet. And, in fact, after this patient’s surgery, his or her doctors told him the vein is still “being pinched off.” Removing the cervical rib didn’t help.
It is important to know that many normal and asymptomatic people have compression of their subclavian veins with arms up. That is not the criterion for diagnosis of venous TOS. My guess is that this patient has a blood clotting disorder. His or her blood may clot too easily.
I feel strongly that an MRI examination would have shown no relationship between the cervical rib and subclavian vein in this patient. That could have saved unnecessary surgery.
I am disappointed every time I learn about a case where doctors don’t seem knowledgeable about TOS. I do realize that very few doctors, including myself, ever received training on TOS in medical school. But most of us have been trained to remain open to new knowledge. TOS carries a strange unscientific stigma fostered by docs who don’t keep an open mind. That doesn’t help patients.
On the other hand, I am encouraged by those patients who advocate for themselves. I have seen some amazing patient arm themselves with research (all praise the higher purposes of the internet!). Some doctors get intimidated by these patients. That’s a bad sign for any patient. Inform yourself, and work with a doctor who is an ally, not an adversary!