Experimental Study on Serial Changes of Tc-99m-MDP Scintigraphy after Tibia Fracture

Byun, Young Soo; Im, Jin Myeong

Abstract

The purpose of this study was to investigate that there was any differences of uptake ratio of Tc99-m-MDP during the healing process related to fracture level in tibia. Thirty mature rabbits were devided into three groups and each group consisted of ten rabbits. The osteotomy was performed at the proximal third of tibia in group I, at the middle third in group II and at the distal third in group III, respectively. After fracture was reduced, the fractured tibia was fixed with K-wire and immobilized with long leg cast. Serial Tc-99m-MDP scintigraphy with pixel counting method was performed in thirty cases of tibial shaft fracture from one day to eight weeks after fracture. The results obtained were as follows: l. In group I, the mean uptake ratio of Tc-99m-MDP at fracture site was 1.40±0.45 at two days after fracture, 3.34±1.21 at two weeks and increased rapidly to a maximal value of 7.51%1.01 at three weeks and decreased thereafter to 4.530.83 at eight weeks. 2. In group II, the mean uptake ratio was 1.10±0.10 at three days, 3.931.±10 at three weeks and increased rapidly to a maximal value of 7.37±2.21 at four weeks and decreased thereafter to 4.54±0.96 at eight weeks. 3. In group III, the mean uptake ratio was 1.13 ± 0.11 at three days, 3.95±0.93 at three weeks and increased rapidly to a maximal value of 7.43±1.72 at four weeks and decreased thereafter to 4.69±0.93 at eight weeks. These experiments suggest that the changes of Tc-99m-MDP scintigraphy in the proximal third fractures of tibia was earlier than middle or distal third fractures and there was no differences between middle and distal third fractures of the tibia.