A Multi-Institutional Study on the Efficacy and Safety of Wearing a Custom-Made Compression Elastic Garment for 6 Months for Klippel-Trenaunay Syndrome with Venous Malformation.

Background: Klippel-Trenaunay syndrome (KTS) is a congenital vascular malformation syndrome characterized by low-flow vascular anomalies, including venous malformation (VM) and lymphatic involvement. These anomalies may lead to limb asymmetry due to soft tissue and/or bone overgrowth. Compression therapy using elastic garments is considered a conservative and minimally invasive first-line treatment option for KTS. However, the benefits of compression therapy for low-flow vascular malformations, particularly limb VMs, have not been sufficiently evaluated. This prospective, multi-center study assessed the efficacy and safety of compression therapy for KTS with VM. Methods: After measuring the affected limb, a custom-made elastic garment providing 30 mmHg of compression was manufactured (THUASNE, France). A total of 20 patients (7 male, 13 female; mean age: 10.9 years) underwent compression therapy for 26 weeks at four nationwide institutions in Japan. The primary outcome was the change in lower limb circumference. Secondary outcomes included pain, modified Rankin Scale (mRS) score, body water content, vital signs, changes in garment elasticity, and adverse events. Results: All 20 patients completed the study. At the study endpoint, the circumference ratio of the affected to unaffected limbs was significantly reduced at the superior end of the tibial tuberosity (p = 0.02) and the thinnest part of the ankle (p < 0.001). The elastic force of the garment declined by approximately 50% over 26 weeks. No serious adverse events related to the intervention were reported. Conclusions: Compression therapy using a custom-made elastic garment appears to be a safe and effective approach for managing limb overgrowth in patients with KTS and VM. To maintain the therapeutic effect, garment replacement is recommended at least every six months.