Endogenous norepinephrine regulates blood flow to the intact rat tibia.

The goal of our study was to determine if endogenous norepinephrine (NE) has a role in the regulation of basal blood flow to intact bone. The experimental plan was to measure bone blood flow before and after pharmacological blockade of alpha-adrenergic receptors. A significant increase in blood flow after receptor blockade would suggest that endogenous norepinephrine exerts a tonic constrictor effect on the vessels supplying blood to the bone. Mature, male rats were anesthetized with Inactin. Arterial blood pressure and left tibia blood flow (laser Doppler flowmetry) were measured. A cannula was inserted into the right iliac artery and advanced to the aortic bifurcation to deliver drugs into the left hindlimb circulation, including the left tibia vasculature. Bolus injection of norepinephrine caused a dose-dependent decrease in bone blood flow (30-40%). Blockade of alpha-adrenergic receptors with phentolamine or phenoxybenzamine attenuated by more than 50% the norepinephrine-induced decrease in bone blood flow. In separate rats that had not received exogenous norepinephrine, injection of phentolamine alone decreased bone vascular resistance by 34+/-3%. Similarly, phenoxybenzamine decreased resistance by 25+/-4%. These results are consistent with the conclusion that alpha-adrenergic receptors mediate a significant constriction of blood vessels which participate in the partial control of basal blood flow to the intact rat tibia.

[Nonoperative approach to injuries of the lateral collateral ligament of the ankle joint]. / Neoperativni pristup povredama lateralnog kolateralnog ligamenta skocnog zgloba.

Patients in number of 185 were included in this study. All of them were treated nonoperatively. One group (64 patients) was treated with early mobilization treatment and the other one (121 patients) with three weeks cast immobilization. Checking examination was done twice: 5 weeks and one year after injury. Chi-square test was used for data processing. Patients treated with cast had shorter recovery, but three were not statistical differences. Positive ADS test one year after the injury (I group 4.7%, and II group 2.5%) was considered as poor result and so was functional instability a year after injury (positive Romberg test, I group 12%, and II group 6.6%). Repeated injury was poor result also. In the first group there were 13.33% repeated injuries and in the second 4.95%.

Malgaigne's fracture: the Larrey variant--a case report.

A rare Malgaigne fracture with caudal displacement of the acetabular section is presented. This variant has not received significant mention in existing literature. It is important because it changes the approach to initial stabilization. Treatment is best accomplished with ORIF and placement of a sacral bar. Significant complications would occur if this variant were mistaken and treated with traction.