Tibial, Pedal, and Inframalleolar Disease

38.1Definition and presentation

Tibial, pedal, and inframalleolar arterial disease becomes clinically urgent when it presents as chronic limb-threatening ischemia (CLTI). CLTI is defined by the presence of objectively documented peripheral artery disease accompanied by tissue threat ACC/AHA 2024 · GVG 2019. The clinical endpoints of treatment are wound healing, relief of ischemic rest pain, preservation of function, and avoidance of major amputation Infrapopliteal Review 2025.

Clinical presentation includes:

• Ischemic rest pain.
• Gangrene (toe, forefoot, or heel).
• A lower-limb ulcer persisting for more than 2 weeks.

38.2Pathophysiology and risk factors

Disease in this segment is strongly associated with diabetes mellitus, end-stage renal disease, and medial arterial calcification. The anatomic pattern is characterized by long tibial occlusions, diffuse calcified stenoses, total occlusions, multisegment disease, and lesions extending below the ankle into the pedal arch ACC/AHA 2024 · Infrapopliteal Review 2025. A technically successful tibial revascularization fails clinically if nonarterial contributors are not controlled; successful tissue preservation requires integrating arterial flow restoration with structured multidisciplinary foot care, including offloading, infection control, and ongoing wound management IWGDF 2024 · IWGDF/ESVS 2023.

38.3Diagnosis and staging

The ankle-brachial index is frequently falsely elevated or incompressible in tibial and pedal CLTI due to calcification. Hemodynamic assessment relies on toe pressures and transcutaneous oxygen pressure (TcPO2) to provide objective perfusion data and guide revascularization necessity GVG 2019. Ischemic rest pain is corroborated by an ankle-brachial index below 0.40, an ankle pressure below 50 mmHg, a toe pressure below 30 mmHg, or a TcPO2 below 30 mmHg (equivalent to WIfI ischemia grade 3); toe pressure is the preferred measure here because tibial and pedal calcification makes the ankle index unreliable, and these numbers are read in clinical context rather than as rigid pass-or-fail lines.

Limb and anatomic staging frameworks stratify risk and replace perfusion-only evaluation. The WIfI classification grades Wound extent, Ischemia, and foot Infection on 0 to 3 scales to estimate 1-year amputation risk and the likelihood of benefit from revascularization GVG 2019 · SVS WIfI 2014. Anatomic complexity is graded by the Global Limb Anatomic Staging System (GLASS), which incorporates an inframalleolar modifier to quantify below-the-ankle anatomic risk and predict outcomes GLASS Inframalleolar · 2023.

38.4Treatment decision and revascularization thresholds

Revascularization is standard care for nonhealing wounds or gangrene in patients fit enough to benefit, aiming to establish in-line flow and maximize wound-bed perfusion ACC/AHA 2024. WIfI stage 4 identifies high limb threat; it does not mean that the limb is unsalvageable. Consider primary amputation or palliation when reconstruction cannot provide a functional, healable limb or when its burden conflicts with the patient’s prognosis and goals. Baseline mobility, rehabilitation potential and patient preference require assessment rather than an automatic exclusion based on non-ambulatory status SVS WIfI 2014. Modality selection turns on anatomy, conduit availability, procedural risk, and local expertise.

The management logic proceeds stepwise:

1. Define the clinical limb threat (WIfI stage) and document objective tissue perfusion (toe pressures or TcPO2).
2. Initiate comprehensive structured foot care, including mandatory offloading and infection control.
3. Grade the anatomic complexity using the GLASS framework, including the inframalleolar segment.
4. Assess great saphenous vein quality and target-vessel outflow serving the wound territory.
5. Compare distal bypass and endovascular reconstruction using patient risk, usable vein, target quality, runoff and wound perfusion. Isolated infrapopliteal disease does not by itself select endovascular treatment, and usable vein does not by itself mandate surgery.

38.5Endovascular and surgical modalities

BEST-CLI remains the foundational randomized comparison for patients with CLTI suitable for either strategy; its primary endpoint was major adverse limb events or death, not mortality alone BEST-CLI · 2022. The 2024 tibial-intervention subgroup included 665 patients with suitable single-segment GSV. At three years, MALE/death was 48.5% after bypass versus 56.7% after endovascular treatment, with similar mortality and fewer major amputations after bypass; amputation-free survival was not significantly different PAD 2024.

BASIL-2 randomized 345 patients requiring infrapopliteal intervention and found more major amputation or death with bypass-first than endovascular-first, adjusted HR 1.35 (95% CI 1.02–1.80), largely because of mortality. This different composite and population do not establish a universal infrapopliteal treatment rule BASIL-2 (2023). Later BEST-CLI publications include the 2025 conduit analysis and anatomic-profile study; these are secondary analyses, not new randomized comparisons BEST-CLI 2025 · PAD 2025.

Device selection for infrapopliteal endovascular intervention is distinct from femoropopliteal algorithms. Paclitaxel-coated balloon angioplasty for infrapopliteal CLTI demonstrated no durable 5-year patency benefit in the IN.PACT DEEP trial and showed an early major-amputation signal that resolved by study completion IN.PACT DEEP (2020). Conversely, LIFE-BTK demonstrated a 1-year primary efficacy advantage for an everolimus-eluting resorbable scaffold over standard angioplasty (74% versus 44% event-free) with non-inferior safety profiles, supporting its use in selected single-device anatomic patterns LIFE-BTK · 2024.

Pedal angioplasty and ultra-distal bypass are potential limb-salvage options, not routine extensions of every tibial procedure. The below-the-ankle systematic review provides territory-specific evidence but is limited chiefly by nonrandomized data Huizing 2019. A 2026 retrospective ultra-distal bypass series included 25 limbs with tissue loss, using pedal or plantar targets; twelve-month freedom from graft failure was 68% and freedom from major amputation 92%. These feasibility outcomes should not be interpreted as comparative superiority over angioplasty Ultra-distal Bypass 2026.

38.6Post-revascularization surveillance

Follow-up criteria depend on clinical progress at the foot. Surveillance evaluates the resolution of rest pain, demarcation of gangrene, and progressive ulcer healing within the boundaries of structured diabetic foot management ACC/AHA 2024 · IWGDF 2024. Best medical therapy runs in parallel: every CLTI patient needs antiplatelet therapy, and after lower-extremity revascularization low-dose rivaroxaban 2.5 mg twice daily plus aspirin reduces major adverse limb events (VOYAGER PAD), alongside a high-intensity statin, smoking cessation, and glycemic and blood-pressure control. Wound stagnation prompts immediate re-evaluation of target-vessel patency, adequacy of collateral pedal arch support, infection control, and mechanical offloading Moysidis et al. (2025).

38.7Areas of controversy

The necessity of strict direct revascularization to the corresponding anatomic angiosome remains debated. Angiosome-directed flow is preferred when feasible, but successful healing is frequently achieved via indirect pathways when collateral networks or the pedal arch are intact Moysidis et al. (2025).

Techniques such as retrograde pedal or distal access are widely used for below-the-knee intervention, but high-quality randomized evidence directly comparing distal and formal antegrade approaches is currently lacking Cochrane Distal Access 2024. The generalizability of drug-eluting resorbable scaffolds to complex, multi-vessel infrapopliteal disease and their durability beyond 1 year remain areas of active investigation Infrapopliteal DES Meta-analysis 2022 · LIFE-BTK · 2024 · Infrapopliteal Scaffolds 2024.

When to reconstruct pedal arteries. Consider below-the-ankle treatment in tissue-loss CLTI when residual pedal disease leaves inadequate flow to the wound despite an adequate proximal reconstruction, and a technically usable pedal path or bypass target remains. Compare targeted angioplasty with distal vein bypass according to conduit, target/runoff quality, procedural risk and expected healing benefit. A visible pedal stenosis alone is not an indication, and evidence does not support routine reconstruction of every pedal-arch defect Huizing 2019 · Ultra-distal Bypass 2026.

Retrograde pedal access is a route for reaching a lesion; it is not synonymous with treating diseased pedal arteries. Document whether the intended benefit is crossing access, improved wound perfusion, or both. BEST-CLI and BASIL-2 inform broader revascularization strategy but do not independently establish the optimal pedal-arch technique BASIL-2 (2023) · PAD 2024.

Further reading

• Endovascular Recanalization for Infrapopliteal Artery Disease in Chronic Limb-Threatening Ischemia: A Practical Review. (2025). Practical infrapopliteal recanalization overview. Infrapopliteal Review 2025
• Below-the-Ankle Angioplasty in Patients with Critical Limb Ischemia: A Systematic Review and Meta-Analysis. (2019). Below-ankle angioplasty evidence in critical limb ischemia. Huizing 2019