ABSTRACT
BACKGROUND: At present, the treatment methods for intertrochanteric fracture of the femur in the aged are in two ways: Intramedullary fixation and extramedullary fixation. The advantages of intramedullary fixation with simple operation, small trauma and few complications have become the gold standard for the treatment of intertrochanteric fracture in the femur in the aged. OBJECTIVE: To explore the clinical curative effects of three internal fixation methods: dynamic hip screw, proximal femoral nail antirotation, and intramedullary nail InterTan in the treatment of intertrochanteric fractures of the femur in the aged. METHODS: A retrospective analysis of 120 cases of intertrochanteric fractures from January 2010 to January 2016 was performed. The patients were randomly divided into dynamic hip screw group (n=40), proximal femoral nail antirotation group (n=60) and InterTan group (n=20). The operative time, intraoperative blood loss, incision length, hospitalization time, postoperative weight-bearing time, fracture healing time, Harris score, and intraoperative and postoperative complications were recorded and compared among the three groups. RESULTS AND CONCLUSION: (1) Operative time, intraoperative blood loss, and incision length were significantly better in the InterTan group and proximal femoral nail antirotation group than in the dynamic hip screw group (P < 0.05). Above indexes were not significantly different between InterTan and proximal femoral nail antirotation groups (P > 0.05). (2) Postoperative weight-bearing time, fracture healing time, and Harris score one month after operation were significantly better in the InterTan group than in the proximal femoral nail antirotation and dynamic hip screw groups; above indexes were better in the proximal femoral nail antirotation group than in the dynamic hip screw group (P < 0.05). (3) Hospitalization time and Harris score at 6 and 12 months after operation were not significantly different among the three groups (P > 0.05). (4) The incidence rate of intraoperative and postoperative complications was significantly lower in the InterTan group and proximal femoral nail antirotation group than in the dynamic hip screw group (P < 0.05). (5) In summary, compared with dynamic hip screw system, proximal femoral nail antirotation and InterTan system are characterized by small trauma, simple operation, quick recovery, and fewer complications, and show good clinical therapy in the treatment of intertrochanteric fracture. Compared with proximal femoral nail antirotation system, InterTan system shows better fracture reduction and stability, shorter healing time, and better biomechanical advantages.
ABSTRACT
OBJECTIVE: To investigate the mechanism of ATP-sensitive potassium channel (K(ATP)) activator cromakalim (CRK) on action potentials and transient inward current (I(ti)) in isolated guinea pig papillary and ventricular myocytes and to explore the mechanisms of effects of I(ti) and K(ATP) treatment in idiopathic ventricular tachycardia. METHODS: The whole-cell patch clamp recording technique was used to detect the action potentials and I(ti) and K(ATP) current alterations during the stimulated and triggered activity. Myocytes were isolated from guinea pig ventricle by enzyme digestion. The experiment was divided into four groups: (1) Control; (2) Control + Ouabain; (3) Control + CRK; (4) Control + Ouabain + CRK. (5) Control + Ouabain + CRK + glibenclamide (GLB). The action potential of guinea pig papillary muscles was measured by using standard microelectrode. The parameters in the experiment included the amplitude (APA), resting potentials (RP), action potentials duration (APD), as well as maximum rise of the action potential (Vmax). RESULTS: (1) When the guinea pig ventricular papillary myocytes were pretreated with Ouabain 0.5 micromol/L, APD prolonged significantly, especially APD(20), APD(50), APD(90). Delayed after depolorazion (DAD) and triggered activity were elicited. I(ti) currents and DAD as well as triggered activity increased. I(ti) current was (126.9 +/- 10.8) pA, lagT (1173.0 +/- 70.9) ms (n = 10, P < 0.01). (2) When guinea pig ventricular myocytes were pretreated with CRK (10 micromol/L), APD was shortened and the amplitude of DAD was lowered. The coupling time in CRK group was significantly prolonged compared with Ouabain group (n = 10, P < 0.01). (3) CRK 50 micromol/L pretreatment of the ventricular myocytes led to an increase of K(ATP) up to (342 +/- 89) pA, which was statistically significant as compared with the control group (P < 0.01). ATP-sensitive potassium channel blocker glibenclamide (10 micromol/L) could antagonize the effects of CRK on APD and I(ti) currents. CONCLUSION: CRK might reduce the toxic effect of Ouabain on cardiomyocytes, shorten APD, terminate DAD and trigger excitation, and have protective effect on cardiomyocytes. The effects of CRK, may be associated with the inhibiting I(ti) current and increasing K(ATP).
