Objective To study the anastomotic relationships of perforators in each zone of the poste-rior leg and design perforating flaps for clinic. Methods Six fresh cadavers underwent a whole body, intra-arterial injection of a lead oxide and gelatine preparation. The posterior part of leg is divided into upper, mid-die and below equal parts, Observe topography of the perforating branches in every district by layer, and mea-sured their location, diameter, course, branches and anastomosis pattern. Radiographs of tissue specimens were digitally analyzed. Results There were 13 perforators that diameter≥ 0.5 mm, the average external diameter was 0.8 mm. The areas of each perforator supplied was average 38 cm2. Perforators from popliteal artery was identified an area 4 cm wide, around the intersection of two lines, a line drawn between the medial and lateral epicondyles of the femurs, and the midline of posterior leg. The areas of the every perforator sup-plied was 55 cm2. These vessels were large in diameter and create multiple true anastomoses with the perfora-tors from the posterior tibial artery or fibular artery. Perforating branches were small in the below part, a long perforator chain comprised of two to three perforators accompanies the Achilles tendon. Conclusion The perforator flaps deviced by perforators from the posterior leg may be transplanted to the lower limbs and the other part of the body. The perforators located in the middle zone of the leg are larger. Free posterior tibial or peroneal perforator-based flaps are reliable, relatively large, and have thin flaps. The upper and lower zones were the larger donor site for the proximal or distally pedicled perforator flap harvest.

Objective To investigate the relationship between the X-ray,CT findings and its pathological basis of nonossifying fibroma(NOF).Methods X-ray and CT features of NOF confirmed by surgical pathology in 17 cases,and correlative study of imaging andpathology was done.Results 17 lesions were showed as eccentric and expanded destruction located in the cortex,and the remains of bone could be found inside the tumor,the lesions projecting into marrow cavity with a thin bone between the tumor and marrow.The tumors were grey-yellow or brown tissue around by the thin bone found in operation.NOF was consisted of a lot of shuttle cell and collagen fiber under microscope,some of macrophagocyte with multiple nucleuses and foam cell dropped disseminating in them,and there was not osteogenesis in the tumor.Conclusion The pathological changes of NOF can be reflected by X-ray and CT.