"Fate of pressure-bearing flaps: long-term observations".

The plantar (weight-bearing) regions of the foot are particularly susceptible to biomechanical stress, placing them at elevated risk for chronic ulceration following surgical reconstruction. This study evaluates the incidence and risk factors for ulceration after free-flap coverage of foot defects, with a focus on anatomical location and mechanical loading. A retrospective review was conducted involving 90 patients who underwent foot free-flap reconstruction between 2015 and 2022, with at least two years of follow-up. Foot defects were categorized into pressure-bearing (plantar) and non-pressure-bearing (dorsal) zones and further subdivided into seven anatomical subunits. Flap survival was 93.3%. Ulceration occurred in 25 patients (27.8%), with significantly higher rates in plantar regions (42.9%) compared to dorsal regions (9.8%) (p = 0.001). Plantar ulcers developed later postoperatively, were more severe (Wagner grade ≥ 3 in 15 cases), and often required surgical interventions, including three amputations. Dorsal ulcers were milder and resolved with conservative care. Subunit analysis showed the forefoot, particularly medial and lateral areas, had the highest ulceration rates. Multivariate analysis identified plantar location as the only independent predictor of ulceration (OR 6.191, p = 0.008). These findings underscore the importance of anatomical considerations in planning and long-term monitoring of plantar foot reconstructions to minimize ulceration risks.