抗感染重组合异种骨对兔胫骨骨髓炎的治疗作用

Therapeutic effect of anti-infective reconstituted bone xenograft on osteomyelit is in proximal tibia of rabbits

目的研究抗感染重组合异种骨(anti-infectivereconstitutedbonexenograft,ARBX)对骨髓炎的治疗作用。方法采用兔胫骨近端骨髓炎模型,于胫骨近端开骨窗注入金葡球菌2周后,再次手术行病灶清除,分别在残留骨缺损中植入ARBX(ARBX组)、植入重组合异种骨(reconstitutedbonexenograft,RBX)并肌注庆大霉素(RBX+全身用药组)、单纯植入RBX(RBX组)以及不植骨(不植骨组)。治疗术后8周取材,通过解剖学、放射学、组织学、细菌学检查,比较上述各组方法对骨髓炎的治疗作用。结果(1)ARBX组细菌计数及改良X线Norden骨髓炎分值极低,明显小于其他各组(P<0.01);其解剖学和组织学观察均无明显的骨髓炎表现。(2)RBX+全身用药组与RBX组的细菌计数、改良X线Norden骨髓炎分值均较高,明显大于ARBX组及不植骨组(P<0.01);其解剖学和组织学均显示出严重的骨髓炎表现。结论(1)在病灶清除后,一期将ARBX植入残留的感染性骨缺损是治疗慢性骨髓炎的较理想方法;(2)传统的全身抗生素应用方法虽较不用抗生素好,但不能确保一期植骨有效治疗慢性骨髓炎。(3)在不用药或传统的全身用药条件下,一期植骨反而会加重骨髓炎。

Objective To investigate the therapeutic effect of anti-infecti ve reconstituted bone xenograft(ARBX)on osteomyelitis. Methods A proximal tibia os teomyelitis rabbit model was used. Twenty animals were randomly assigned to 4 gr oups and all of them were injected with staphylococcus aureus through a bone win dow. Two weeks postoperatively the animals underwent clearance of the focal lesi on, followed by implant of 3 pellets of ARBX containing 30 mg of gentamicin in g roup Ⅰ, 3 pellets of reconstituted bone xenograft (RBX) in conjunction with 30 mg of intramuscular gentamicin for 5 days in group Ⅱ, 3 pellets of RBX without antibiotic in group Ⅲ, and those in group Ⅳ were left without bone grafting. S pecimens were harvested 8 weeks after the above procedures and were then subject ed to gross observation, radiological, histological and bacteriological examinat ions to compare their therapeutic effect on osteomyelitis. Results 1) In group Ⅰ the bacteria counting and modified Norden scoring were by far the smallest am ong all 4 groups (P< 0.01), with no histological and gross manifestations of ost eomyelitis. 2) The bacteria counting, modified Norden scoring as well as the his tological and gross manifestations in group Ⅱ, Ⅲ were at the same levels and w ere less than those in group Ⅳ(P< 0.01). Conclusion 1) ARBX could be implanted as primary graft into the remaining infected defect after debridement to effecti vely treat osteomyelitis, serving as an ideal treatment option for chronic osteo myelitis. 2) Conventional systemic administration of antibiotics following debri dement was not effective in primary bone grafting treating osteomyelitis. 3) Pri mary bone grafting would rather make the condition worse, when low dosage system ic or not any antibiotic was being used.