The arterial blood supply of a typical human rib has not been clearly described. Some authors believe that the nutrient artery is the main source of blood supply to the rib while others believe that the periosteal supply is adequate. The first part of the study was undertaken to describe the arterial supply of a typical human rib. Individual ribs from fresh cadavers, fresh foetuses and embalmed cadavers were injected with different injection media, subjected to radiological analysis and dissected. The outcome indicated that a typical human rib received its arterial blood supply from the periosteal branches of the anterior and posterior intercostal arteries. A nutrient artery was not found.
It is common practice for orthopaedic surgeons to utilize free rib grafts to replace diseased or injured vertebrae in order to stabilize the vertebral column following instability of the vertebrae. However, although this is successful in most instances, there are few objective studies relating to the preferential use of nonvascularized or vascularized ribs for grafting.
In the pilot study, comprising six adult cats, vascularized rib grafts were compared to nonvascularizcd rib grafts. !n three cases, a periosteally vascularized rib segment with its neuro-vascular muscular pedicle was excised and in the remaining three cases, a periosteal free, non vascularized rib segment was removed. These rib segments were then grafted into artificially created vertebral receptor sites. The results indicated that all grafts were viable at six months as shown macroscopically, radiographically and histologically. However, the vascularized grafts were more robust. At three months, the non vascularized grafts showed medullary necrosis and the pedicled grafts, having retained their blood supply, had a viable medullary cavity. At six months the non vascularized grafts showed renewed vitality and were comparable histologically to the pedicled grafts. In addition, new bone formation occurred along the pedicle in one of the vascularized grafts. Although both the vascularized grafts and the non vascularized grafts survived, the early superiority of the vascularized grafts would support the use of this graft in clinical situations where anterior stabilization of the vertebrae is required.
|Subject||Medical sciences: Physiology|
|Subject 2||Medical sciences: Physiology|
|Degree Type||Masters degree|
|Degree Description||M MedSc|