ISSN:0885-9698    

出版商:OVID    

年代:1996

数据来源: OVID

ISSN:0885-9698    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Summary:Transoesophageal echocardiography demonstrates transatrial echogenic events during intramedullary reaming procedures. These vary in intensity and are sometimes severe, prolonged, and fatal. There is an association between intramedullary reaming and activation of the coagulation system. Major coagulative events may be evident during echocardiography.

ISSN:0885-9698    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Summary:Even though the problems of intramedullary pressure increase and its effects on pulmonary function have not yet been resolved, intramedullary nailing after reaming remains a relevant treatment procedure, especially for pseudarthrosis of the tibial and femoral shaft, because good results have been achieved in these areas. Our study aimed to clarify whether modifications to reamer and shaft design would reduce intramedullary pressure increase. Measurements were taken in plexiglass tubes filled with a vaseline/paraffin oil mixture with viscoelastic properties at 20°C, corresponding to the viscoelastic properties of bovine medullary fat at 36°C. Measurements were also taken at the metaphysis in pairs of human femora. The results clearly show that a reduction in shaft diameter will produce a sustained reduction of intramedullary pressure and that the modification of reamer design combined with thinner shafts will lead to a further reduction. In comparison with the conventional AO reaming system (9.0-mm shaft + 9.5-mm AO reamer), the use of thinner shafts and a modified reamer design reduced intramedullary pressure as follows: (a) 9.0-mm shaft + 9.5-mm hollow reamer by 22%; (b) 7.0-mm shaft + 9.5-mm AO reamer by 47%; (c) 7.0-mm shaft + 9.5-mm hollow reamer by 65%; and (d) 6.0-mm shaft + 9.5-mm hollow reamer by 75%. These results show how efficiently the intramedullary pressure increase during reaming can be reduced by simple modification, which in turn minimizes the risk for the patient.

ISSN:0885-9698    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Summary:Sixty-two percent of cortical blood flow in the tibial diaphysis is supplied by the tibial nutrient artery, and thus the normal blood flow is centrifugal in direction. Intramedullary reaming destroys the nutrient artery and injures the endosteal surface of the cortex. For this procedure to be physiologic, blood flow to the cortex and fracture site must be recruited from a different, nonendosteal, compensating source. Trueta suggested that blood-flow direction can reverse from centrifugal to centripetal, depending on the physiological conditions, and in particular, after breakdown of the normal endosteal blood supply. We examined this hypothesis after intramedullary reaming of the intact and osteotomized ovine tibia. The cortical and periosteal blood flow to intact reamed tibiae was measured in eight sheep. The cortical and periosteal blood flow to tibiae that had undergone an experimental osteotomy before intramedullary reaming was measured in six sheep. 57Cobalt-radiolabeled microspheres were used to measure blood flow. The unoperated contralateral tibiae served as controls. Immediately after reaming of the intact tibial medullary canal, there was no significant change to cortical blood flow, but there was a significant sixfold increase in the periosteal flow. After reaming of the osteotomized tibiae, there was a significant threefold increase in periosteal flow. Our study confirms Trueta's hypothesis that after trauma or other pathologic states, cortical blood flow direction can be reversed.

ISSN:0885-9698    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Summary:The compartment syndrome is a known complication of limb injury. It has been suggested that intramedullary reaming before the insertion of a nail generates unphysiologic pressures in the medulla, resulting in elevated compartment pressures, and thus the unreamed nail is preferable if the specific injury carries the risk of developing an acute compartment syndrome. We examined the effect of intramedullary reaming on compartment pressures in isolation. We investigated intramedullary pressures during intramedullary reaming of the intact ovine tibia and recorded pressures in the anterolateral and deep posterior compartments simultaneously. Muscle blood flow was measured in four anatomically distinct muscle groups (anterior, lateral, deep posterior, and gastrocnemius), by using radiolabeled microspheres —30 min after reaming. Before intramedullary reaming, different positions of the lower limb caused considerable elevations of compartment pressures. During reaming, intramedullary pressure increases >940 mm Hg were recorded, resulting in elevations of compartment pressures. All increases of pressure were transient, and in no case was a persistent increase in compartment pressure observed. There was no decreased blood flow in the soft tissues after reaming. We conclude that intramedullary reaming as such does not lead to the development of an acute compartment syndrome.

ISSN:0885-9698    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Summary:Reaming of long-bone fractures has caused some controversy as to whether the reaming or intramedullary nailing causes acute compartment syndrome. Reaming itself causes a transient rise in compartment pressure that is not maintained postoperatively. Acute compartment syndrome can, however, be precipitated by maneuvers common to all methods of fracture treatment, such as traction and reduction.

ISSN:0885-9698    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Summary:Experimental evidence from animal models has suggested that bone reamings may enhance fracture healing, but data are limited and unconvincing. Clinical data supporting an osteogenic role for reaming products are mainly circumstantial. Reamed nailing is an established method of treating long bone nonunions and it has been suggested that reaming products play an important role. Recent studies on the use of reamed nails for tibial fractures have not shown significantly higher rates of union compared to unreamed models. The most recent experimental studies on reaming suggest it may greatly increase periosteal blood flow, which may also have a profound effect on fracture healing. The precise osteogenic role of bone reamings has therefore still to be clarified.

ISSN:0885-9698    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Summary:Pulmonary failure is a common complication in poly-traumatized patients with long-bone injuries. Current treatment protocols include early osteosynthesis of these fractures. This has been shown to decrease pulmonary complications, including fat embolization and the development of adult respiratory distress syndrome. Currently there is controversy over whether the fat embolization that occurs as a result of reamed femoral intramedullary nailing may be harmful, especially to poly-traumatized patients with thoracic trauma. This article will review the literature on fat embolization and fat embolization syndrome and will review studies examining possible associations between intramedullary fixation of long-bone fractures and the development of respiratory failure.

ISSN:0885-9698    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Summary:Shaft fractures of the femur or tibia or both are frequent components of multiple trauma. Besides the local fracture impact, they induce considerable systemic distress to remote organs because of pain, blood loss, necrotic or hypoperfused tissues, and mediator release. Additionally, unstable skeletal conditions (particularly of the lower extremities) impede optimal intensive care of these patients. Therefore in a polytrauma setup, primary operative stabilization of the femur is mandatory and generally accepted, whereas the optimal fixation procedure is still a source of controversies. The fracture per se and the manipulation of fragments may cause additional release of mediators and pulmonary embolism of microaggregates. Related to this, there is striking clinical and experimental evidence that reaming of the intramedullary cavity and inserting a nail generates extremely high temperatures and pressures within the intramedullary canal and induces a critical amplification of the release and embolism phenomena described. Therefore, the multiply injured (with the endogenous defense systems already close to decompensation) should not additionally be endangered by undue medical procedures, and the biomechanically best fixation technique should not be used, in favor of alternative procedures with a lower systemic distress level. We describe a treatment algorithm that appeared to be successful in a number of multitrauma situations.

ISSN:0885-9698    

出版商:OVID    

年代:1996

数据来源: OVID