Single-stage Resection of Type II Constriction Rings in Limbs on the Basis of Histological and MRI Observations: A Retrospective Study of 21 Consecutive Patients

Objective: To determine the feasibility of single-stage resection for type II congenital constriction rings via histological examination of resected specimens and imaging examination of affected extremities, and to evaluate the appearance and function of the extremities after the single-stage operation. Methods: The features of the skin on the constriction rings and the subcutaneous tissues were identified through continuous sectioning, hematoxylin and eosin (HE) staining, and immunohistological staining of specimens of type II constriction rings obtained via surgery. The relationship between the constriction rings and the deep main blood vessels was evaluated using magnetic resonance imaging (MRI). Single-stage resection of the constriction band, reduction of the fascial flap, and triangular flap plasty were performed for 21 patients. The appearance, lymphedema, and movement of the extremities were compared before and after the operation. Results: Type II constriction rings in the extremities had normal full-layer skin structures. Collagen was found deposited densely at the base of the grooves, but the normal subcutaneous tissue space still existed, and the vital nerves and blood vessels were unaffected. Complete resection of the constriction rings was achieved in all 21 patients, and lymphedema subsided 2 months after the operation. No episode of recurrence was found, and limb function was not affected at 26 months of follow-up. Conclusion: Type II congenital constriction rings in limbs possess normal subcutaneous tissue spaces. A single-stage operation, which includes complete resection of the rings, fascial flap reduction, and triangular flap plasty, could achieve satisfactory appearance and good function.