To study 15 patients with anular ligaments formed operation on children s old Monteggia fracture;

Reconstruction of annular ligament with dilurn polyester felt cardiac patch in the treatment of dislocation of capitulum radius;

Methods Fifteen patients with old Monteggia fracture in children were treated with open reduction,osteotomy of the ulna and restoration or angioplasty of annular ligament.

In our previous subacute cases, we found that the annular ligament was intact and tensely stuck in the radiohumeral joint space.

Re- sults:Thyroid cartilage,cricoid cartilage,thyrohyoid membrane,cricothyroid ligaments,quadrangular membrane and elastic cone,etc.

Then their larynxes were harvested,the inner diameters of these larynxes were measured and the cross-sectional area of the cricoid cartilage was calculated.