The Giacomini vein courses the posterior thigh as either a trunk projection, or tributary of the SSV.

[2] Another study in India found the vein to be present in 92% of those examined.

[3] It is located under the superficial fascia and its insufficiency seemed of little importance in the majority of patients with varicose disease, but the use of ultrasonography has highlighted a new significance of this vein.

The direction of its flow is usually anterograde (the physiological direction) but it can be retrograde when this vein acts as a bypass from an insufficient GSV to SSV to call on this last one to collaborate in draining.

It has been shown to be effectively treated either with endovenous laser ablation or by ultrasound guided sclerotherapy.