The Shimotsuki Family is a renowned and formerly powerful family from Wano Country. Centuries ago, Shimotsuki Ryuma became a well known swordsman in Wano to the point his actions became legends. The Shimotsuki Family grew to become a respected family in Wano, having two of the country’s regions entrusted to them.

In Wano, after Kurozumi Orochi and the Beasts Pirates took over, the known family members sided with the Kozuki Family, resulting in Ushimaru’s death and Yasuie going into hiding for the next 20 years.

When we saw Ushimaru’s back, we can see the Shimotsuki family crest is tattooed on his back. The regular swords we know of are there, but they’re also framed by something on the outside. I’m going out on a limb and guessing they’re wisteria, which incidentally is the flower Oda said represented Zoro in SBS volume 95.

Historically, Wisteria symbolizes long-life and immortality. Wisteria can live up to 100 years or even older (Ryuma? or linking to how the Shimotuki clan is an ancient one?). There is a 1200 year old Wisteria tree in Japan today! They’re widely used in Japan throughout the centuries and were a popular symbol in family crests and heraldry.

It’s also a Buddhist symbol (Zoro has lots of Buddhist ties) and its flowers “symbolize the simultaneous brilliance and impermanence of life”. Doesn’t mean too much other than maybe how some Shimotsuki’s have died in the story (Yasuie, Ushimaru, Kuina), their deaths being quite impactful to Zoro’s life?

It probably wouldn’t give too much or take much from the story but it’d be kind of cool I think.