^(99m)Tc-MDP骨显像在监测带肌蒂骨移植中的价值

Evaluation of^(99m)Tc-MDP bone imaging in monitoring the muscle-pedicle bone graft osteogenic activation

选用成熟体健家犬 9条 ,随机分为 4组 ,采用自身对照法 ,动物左侧为实验侧 ,切取带缝匠肌的髂骨块 ,右侧为对照侧 ,将骨瓣游离后用医用硅胶膜包裹 ,固定于大腿外侧 ,术后 2、4、6、8周从右侧切取与实验侧大小一样的骨块 ,以放射性核素骨显像、组织学检查等方法 ,观察肌蒂移植骨存活范围和成骨活动形式 ,探讨带蒂移植骨在治疗股骨头缺血性坏死方面的价值。结果显示 :(1)带缝匠肌髂骨瓣为一部分存活骨 ,在距离 1.2— 1.7cm处开始出现骨组织坏死。 (2 )带缝匠肌髂骨瓣成骨活动有两种方式 ,存活骨在机械性刺激和血供减少的情况下 ,骨髓组织被纤维肉芽组织和新生毛细血管替代 ,远端死骨则是由近端存活骨向其爬行替代。 (3)组织学检查 2周时死骨内有少许纤维肉芽组织和新生毛细血管 ,6周时出现原始骨小梁 ,8周时部分骨小梁恢复正常形态 ,骨母细胞明显减少。 (4)带肌蒂骨瓣存活范围与肌蒂宽度成正比关系。由此可见 ,带缝匠肌髂骨瓣是一块血供欠佳的骨瓣 ,对股骨头坏死和塌陷的修复是有限的。放射性核素骨显像能早期判断带蒂移植骨的成活情况。

Nine mature and healthy dogs were divided into 4 groups randomly. The first group consists of 3 dogs, and the rest groups, 2 dogs. Self-control way was used. The left ilium was the experimental site, where the bone piece with sartorial muscle attached was cut from ilium. The right side served as control, where the graft bone from ilium was wrapped up with silica gel, then fixed subcutaneously. The pedicled bone pieces were retrieved in 2, 4, 6, 8 week after surgery, the size of graft bones from two sides were the same. Survival range, osteogenic formation of muscle-pedicle bone were examined by 99mTc-MDP bone imaging and histological method to evaluate the clinical value of treatment of ischemic osteonecrosis of the femoral head with muscle-pedicle bone grafting. The results were as follows: 1. The part of bone attached by the sartorial survived, but osteonecrosis was observed at the location of 1.2-1.7 cm from attached point of muscle. 2. There were two forms observed in the course of osteogenic activation of muscle-pedicle bone. Under the reduction of mechanical stimulation and blood supply, bone marrow tissue was replaced by fiberogranulation tissue and new capillary in the survival part, while the survival bone of proximal part grew distally and gradually replace the dead bone of distal part. 3. Histological examination revealed that small amounts of fiberogranulation tissue and new capillary appeared in 2nd week, primary trabeculae appeared in 6th week, and in 8th week, some trabeculae recovered their normal appearance and osteogenic cell reduced remarkably. 4. Survival range of muscle-pedicle graft bone was directly proportional to the width of muscle pedicle. Therefore, radionuclide bone imaging and histological examination demonstrated that muscle-pedicle grafte bone was a piece of bone with relatively poor blood supply, its effect in repairing necrosis and collapse of the femoral head is limited. 99mTc-MDP bone imaging may be an effective and first choice method for the early monitoring of the muscle-pedicle bone graft osteogenic activation.