Effect of platelet-rich plasma combined with demineralised bone matrix on bone healing in rabbit ulnar defects.

INTRODUCTION: This study evaluates the effect of autologous platelet-rich plasma (PRP) combined with xenogeneic demineralised bone matrix (DBM) on bone healing of critical-size ulnar defects (2-2.5 times the ulnar diameter) in New Zealand White rabbits. METHODS: Critical-size defects were created unilaterally in the ulna of 36 rabbits, while keeping the contralateral limb intact. They were divided into three groups. In Group A, the defect was filled with autologous PRP and in Group B, with autologous PRP combined with DBM; in Group C, the defect remained empty. The rabbits were euthanised 12 weeks postoperatively. Radiological, biomechanical and histological assessments were carried out and statistical analysis of the results was performed. RESULTS: Group B had significantly higher radiological and histological scores than Groups A and C. Defects in Group B showed significant new bone formation, whereas there was minimal or no new bone formation in Groups A and C. Only specimens in Group B showed macroscopic bone union. Biomechanical evaluation of the treated and intact contralateral limbs in Group B showed significant differences. CONCLUSION: In this study, statistically significant enhancement of bone healing was found in critical-size defects treated with PRP and DBM, as shown by radiological findings, gross assessment, and biomechanical and histopathological results. Defects in the two other groups remained unbridged. Therefore, PRP was effective only when it was used in combination with a bone graft.

The Effect of Low Molecular Weight Heparins on Fracture Healing.

Venous Thromboembolism is a serious complication in the trauma patient. The most commonly studied and used anticoagulant treatment in prophylaxis of thrombosis is heparin. The prolonged use of unfractionated heparin has been connected with increased incidence of osteoporotic fractures. Low molecular-weight-heparins (LMWHs) have been the golden rule in antithrombotic therapy during the previous two decades as a way to overcome the major drawbacks of unfractioned heparin. However there are few studies reporting the effects of LMWHs on bone repair after fractures. This review presents the studies about the effects of LMWHs on bone biology (bone cells and bone metabolism) and underlying the mechanisms by which LMWHs may impair fracture healing process. The authors' research based on literature concluded that there are no facts and statistics for the role of LMWHs on fracture healing process in humans and the main body of evidence of their role comes from in vitro and animal studies. Further large clinical studies designed to compare different types of LMWHs, in different dosages and in different patient or animal models are needed for exploring the effects of LMWHs on fracture healing process.

Georges-Paul Dieulafoy (1839-1911) and the first description of "exulceratio simplex"

Professor Georges Dieulafoy is considered to be an outstanding clinician who played a leading role in medicine during the 19th century. He invented the well-known Dieulafoy aspirator, he described a triad for the diagnosis of acute appendicitis and he tried to bridge the gap between internal medicine and surgery. This article presents in details the first description of "exulceratio simplex" that bears his name.

Sexual dimorphism of the hip joint in Greeks.

The objective of the present study was to report our measurements of hip bones within the Greek population and review the possible implications of these differences in their health as well as in social life. For this purpose the remains of 100 male and 100 female pelvic and femoral bones were studied. The distance from the pubic tubercle to the anterior rim of the acetabulum, the acetabulum diameter between its rims, their ratio, the depth of the acetabulum, the diameter of the femoral head and the ratio between the femoral head and the diameter of the acetabulum were measured. It was found that in males, in comparison to the females, the distance from the pubic tubercle to the anterior rim of the acetabulum was smaller while the acetabulum diameter and its depth, the diameter of the femoral head and the ratio between femoral head and the acetabulum diameter were larger. The above differences reached strong statistical significance. Of the two ratios used only the first one reached statistical significance. Using this ratio alone offered the best discrimination rate of up to 99% and should be the preferred choice when available.