Objective: Thromboangiitis obliterans (Buerger disease) is known as an intractable vascular disease that has been reported as thrombosis in distal arteries and occasional venous occlusion, as well as inflammatory changes in the thrombus and vascular wall. Patients often require limb amputation due to limb necrosis. Corkscrew (CS), a small arterial coiling, is an important diagnostic finding that was mainly found with angiography. Recently, however, it can also be identified using a modern ultrasonographic technique. Methods: In thease 22 cases, in 48 areas of study, we used the ultrasonographic technique to identify the CS, which allowed us to observe its relationship with the surrounding nerves and arteries. Results: In all cases, it was possible to identify the CS easily and it was confirmed that the CS and the nerve were carried down in their sheath. The sites of the CS existed in areas other than the area around the occluded main arteries and some CS that ran inside the nerve (16 areas) and some CS that accompanied the outside of the nerve (10 areas) were confirmed, suggesting the CS work as collateral blood supply vessels, with well-developed normal vessel-like anatomy. Conclusion: When we observe the CS, it is important to observe not only around the main trunk artery, but also areas where nerves mainly run, even if they do not accompany the main trunk artery.
