Transverse tibial bone transport promotes distraction osteogenesis and improves blood flow in the management of diabetic foot

BACKGROUND Diabetic foot ulcers (DFUs), a common and severe long-term complication of diabetes, are associated with high rates of amputation and mortality. Transverse tibial bone transport (TTT) has recently been applied in DFU management to accelerate wound healing. AIM To explore the potential mechanism through which TTT aids in the treatment of DF, with a special focus on the role of postoperative distraction osteogenesis and angiogenesis in the affected limb. METHODS Fifteen patients with DFUs (Wagner grades 2-5) treated with TTT were enrolled. Pain intensity was assessed using the Visual Analog Scale (VAS), and skin temperature and Ankle-brachial index (ABI) were measured at 1 week, 1 month, and 6 months postoperatively. Wound healing was assessed by tracking the duration and rate of healing. Computed tomography (CT) scans of both lower limbs were conducted before and 1 month after surgery to evaluate distraction osteogenesis, and CT values of the corresponding medullary cavities of the bone blocks were recorded. High-frequency color Doppler ultrasonography was used to assess popliteal artery (POA) blood flow, inner diameters, and velocities of the three middle arteries of the lower leg and dorsalis pedis artery, and the number of collateral vessels of the three middle arteries. Plantar microcirculation was measured before and 1 month after surgery using the laser Doppler flowmetry system PeriScan PIM3. RESULTS Complete wound healing occurred in all patients, with a mean healing duration of 10.1 ± 3.7 weeks. The regenerated skin showed no clear boundary with the surrounding tissue and revealed a visible dermatoglyphic pattern. CT imaging 1 month postoperatively revealed substantial bone formation beneath the distracted bone block, with alignment consistent with the direction of distraction; showing a transverse arrangement, no obvious bone aggregation was observed in the corresponding part of the medullary cavity before surgery. Postoperative assessments revealed significantly increased foot skin temperature and ABI values, accompanied by significant reductions in VAS scores (P < 0.05). CT values of the distracted bone block increased significantly compared to the baseline. POA blood flow was significantly greater at 1 month postoperatively than before surgery. B-ultrasound examinations revealed that collateral branches around the three middle arteries of the lower leg were sparse preoperatively. One month after surgery, the number of collateral vessels increased significantly, although their inner diameters showed no significant change, while blood flow velocity increased significantly. Laser Doppler analysis further revealed that the plantar skin blood flow signals were sparse, indicating poor microcirculatory perfusion before surgery. CONCLUSION In patients with DR, TTT appears to promote ulcer healing by enhancing limb blood circulation. This effect is associated with distraction osteogenesis at the surgical site, which supports collateral angiogenesis. These findings suggest a relationship among distraction osteogenesis, local angiogenesis, and improved tissue perfusion that may contribute to ulcer healing; however, the causal mechanisms underlying this relationship remain unclear.