1991 Fiscal Year Final Research Report Summary
Experimental study of vascularized bone grafts in rabbit
| Project/Area Number |
01570845
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Orthopaedic surgery
|
|---|
| Research Institution | Nara Medical University |
|---|
Principal Investigator |
TAMAI Susumu Nara Medical University Professor, 医学部・整形外科, 教授 (10075088)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
川西 弘一 奈良県立医科大学, 医学部・整形外科, 大学院生
YAJIMA Hiroshi Nara Medical University Assistant, 医学部・整形外科, 助手 (20221640)
|
|---|
| Project Period (FY) |
1989 – 1991
|
| Keywords | vascularized bone graft / radioactive microsphere / bone blood flow / living bone graft |
|---|
| Research Abstract |
The purpose of this study was to quantify the bone blood flow in long bone transplanted to another long bone, and investigate bone dynamics under different mechanical and biological environments using rabbits. Three experimental groups were performed. Vascularized group : The right 2nd metatarsal bone was elevated with the saphenous vessels as a vascularized bone graft. The graft was transplanted to a 1.5cm defect prepared in the femoral diaphysis and fixed with an external fixator. Conventional group : nonvascularized metatarsal bone graft of which the surrounding soft tissues were stripped away was transplanted with the same manner. Non weight-bearing group : Vascularized metatarsal bone graft was transplanted into the femoral subcutaneous tissue.
The radioactive microsphere method was used for the measurement of the bone blood flow. In the vascularized group the blood flow of the graft had immediately increased. At one week postoperatively, the mean blood flow was 11.8ml/min/100g of bone, at 3 weeks, 17.4. at 6 weeks, 13.3. At 9 weeks, the mean blood flow significantly decreased to 3.9 and at 12 weeks, 3.6. The diameter of the graft increased until 6 weeks, as larger as 1.6 times larger than the contralateral metatarsal bone, but subsequently no progression of the hypertrophy was noted.
In the conventional group, the mean blood flow gradually increased to 6.8 ml/min/100g at nine weeks postoperatively and it was 6.4 ml/min/100g at 12 weeks.
In the non weight-bearing group, the mean flow in the bone grafts immediately increased to 10.4ml/min/100g at 1 week postoperatively. It was 7.0ml/min/100g at 3 weeks and 6.5ml/min/100g at 6 weeks.
Our experiments demonstrated that hypertrophy occurs in response to biomechanical and biological demands in the presence of a rich bone blood flow.
|
