Venous Stasis Ulcers: Given the description of rudeness (likely referring to roughness or dryness) of the lower extremity, presence of crusted ulcers without signs of infection, and a duration of over a year, venous stasis ulcers are a strong consideration. Venous stasis ulcers typically occur on the lower legs, are often associated with venous insufficiency, and can present with dry, scaly skin and ulcers that are not necessarily infected.

Chronic Venous Insufficiency: This condition can lead to skin changes, including dryness and ulcers, similar to what is described. It's closely related to venous stasis ulcers but encompasses a broader range of symptoms related to poor venous circulation.
Arterial Ulcers: Although less likely given the absence of pain and the description, arterial ulcers can occur and present with dry, gangrenous changes, especially in the context of poor arterial circulation.
Diabetic Foot Ulcers: These ulcers can present in a variety of ways, including being dry and not infected, especially in the context of neuropathy. However, they are typically associated with diabetes mellitus and might have other distinguishing features.

Squamous Cell Carcinoma: Although rare, chronic ulcers can undergo malignant transformation. It's crucial to consider this possibility, especially if there are any atypical features or if the ulcers are not responding to standard treatments.
Deep Vein Thrombosis (DVT): While DVT typically presents acutely with swelling, warmth, and pain, chronic DVT or post-thrombotic syndrome can lead to skin changes and ulcers due to chronic venous obstruction.
Vasculitis: Certain forms of vasculitis can present with skin ulcers. Although less common, missing this diagnosis could have significant implications for treatment and prognosis.

Pyoderma Gangrenosum: A rare skin condition characterized by painful ulcers, which might not always present with the typical signs of infection.
Sickle Cell Ulcers: In patients with sickle cell disease, ulcers can occur due to sickling crises affecting the microcirculation.
Ehlers-Danlos Syndrome: Some types of Ehlers-Danlos syndrome can lead to poor wound healing and the formation of ulcers due to fragile skin and blood vessels.