Why is unna's boot not recommended for wheelchair-bound and bedridden patients?

Yes: Unna boots can cause a slight decrease in circulation due to their constricting nature when placed. When patients are bedridden and wheelchair bound, they may have a decrease in circulation which may be additive to the unna boot constriction and cause ischemia to the lower extremity.

Calf contraction: An unna's boot provides compression that is highest under calf contraction such as with walking. The bandage exerts a force that resists blood being driven to the surface. When the calf muscle is resting, there should be minimal pressure being exerted by the bandage. Patients with limited mobility will benefit little from the unna's boot compression due to the lack of calf muscle contraction.