Chronic limb-threatening ischemia (CLTI) is the most severe form of peripheral artery disease and remains a major health problem. Although the angiosome concept was introduced to guide revascularization by restoring direct blood flow to the affected tissue, its usefulness is limited by anatomical variations, collateral circulation, and wounds involving multiple territories. The emerging "woundsome" concept focuses instead on improving arterial perfusion directly to the wound area, recognizing that both direct revascularization and

Chronic limb-threatening ischemia (CLTI) represents the most advanced stage of lower-extremity peripheral artery disease and is a major global health concern with increasing prevalence and significant health-care costs. Technological advancements, evolving revascularization strategies, and improved surgical and endovascular expertise have reduced the number of patients considered unsuitable for revascularization. Recent vascular guidelines acknowledge limitations in incorporating terminal circulation into treatment algorithms.

The angiosome concept describes six angiosomes in the foot and ankle supplied by the three main infrapopliteal arteries and was proposed as a method to guide revascularization and ensure direct blood flow to affected tissues. However, its utility is limited by variations in anatomy, the presence of collateral circulation, and the contribution of vessels such as branches of the peroneal artery. The condition of the pedal arch also plays an important role.

Additionally, larger wounds often involve more than one angiosome, which complicates the application of this concept. The "woundsome" concept has therefore emerged, emphasizing targeted improvement of arterial blood flow directly to the wound area in patients with CLTI and tissue loss. Evidence suggests that direct arterial perfusion to the wound is associated with better outcomes in limb salvage and wound healing. At the same time, the presence and quality of collateral circulation following indirect revascularization can also significantly influence clinical success and may provide outcomes comparable to direct revascularization.

Inclusion criteria:

1. Patients with chronic limb-threatening ischemia (CLTI) with tissue loss (Rutherford Class 5 or 6, or WIFI stage 2-4) 2. Patients with infrapopliteal arterial occlusions requiring revascularization

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Exclusion Criteria:

1. Patients with unsalvageable limbs

2. Patients with acute limb ischemia (ALI)

3. Patients with non-atherosclerotic diseases such as vasculitis, including:

   Large vessel vasculitis (e.g., giant cell arteritis, Takayasu arteritis) Medium vessel vasculitis (e.g., polyarteritis nodosa, Kawasaki disease) Small vessel vasculitis (e.g., granulomatosis with polyangiitis, microscopic polyangiitis) Other types (e.g., Behçet's disease, Buerger's disease)

4. Patients with contraindications to contrast medium

5. Patients with aortoiliac or femoropopliteal occlusive disease