ABSTRACT
Objective To report the treatment effects of open reduction and internal fixation with bone plate through a small posterior heel plus tarsal canal incision on closed calcaneal fractures.Methods A retrospective study was done of the 20 patients (25 feet) who had been treated at Ward One,Department of Orthopaedics,People's Hospital of Yunfu from February 2016 to February of 2019 for closed calcaneal frac-tures by open reduction and internal fixation with bone plate through a small posterior heel plus tarsal canal incision.They were 16 males and 4 females,aged from 16 to 60 years.According to the Sanders classification,there were 3 cases of type Ⅱ,15 cases of type Ⅲ and 2 cases of type Ⅳ.Their fractures were reduced by traction,extruding,prying and direct visualization through the tarsal canal window;the bone plates were inserted through a small incision at the back of the heel and fixated by screws.Postoperative observation was done to address fracture healing,and length,width,height,B(o)hler angle and Gissane angle of the affected calcaneus,as well as functional recovery of the ankle-hindfoot by the American Orthopaedic Foot and Ankle Society (AOFAS) evaluation.Results The operation time for a single foot ranged from 45 min to 70 min,averaging 64.5 min;the intraoperative fluoroscopy for a single foot ranged from 3 times to 6 times,averaging 4.5 times.Local skin necrosis of about 0.5 cm x 0.3 cm appeared in one foot after operation but responded to dressing change.No other wound complications occurred.Their follow up was carried out for 6 to 36 months (average,17.3 months).The fractures healed well with well-shaped bony callus and flat articular surface after 4 to 6 months.The length (80.5 mm ±4.2 mm),width (44.8 mm ±5.2 mm),height (44.4 mm ±3.0 mm),B(o)hler angle (25.0° ± 5.1 °) and Gissane angle (113.8 ° ± 8.6°) of the calcaneus at the last follow up were significantly improved than the preoperative values (79.4 mm ± 4.5 mm,50.5 mm ± 6.3 mm,40.0 mm ±4.4 mm,12.0°± 13.8° and 107.0°± 13.3°) (all P ＜ 0.05).By the AOFAS ankle-hindfoot scale,functional recovery of the foot was excellent in 20,good in 3 and fair in 2 cases,giving an excellent to good rate of 92％.Conclusion In the treatment of closed calcaneal fractures,open reduction and internal fixation with bone plate through a small posterior heel plus tarsal canal incision may lead to fine outeomes due to its advantages of small incision and fine fracture reduction.
ABSTRACT
Objective To investigate the effects of modafinil,a new wake-promoting agent,on simulated flight performance during 48 h sleep deprivation(SD).Method Six male healthy young volunteers were exposed to two periods of 48 h continuous wakefulness during the crossover experiment.In one period,three 200 mg doses of modafinil were given and in the other,separated by two weeks,matching placebos were administered.The SD time started from 8:00 of the first day to 8:00 of the third day.Drug was given at 0:00,16:00 of the second day and 0:00 of the third day.Flight performance in J7-E flight simulator was tested at 21:00 of the first day and 1,3,5,7 h after each drug administration.Result The scores of simulated flight performance in the placebo group decreased with time during SD and became significant at 1:00～7:00 of the third day.Numbers of errors increased with time during SD,especially in the left ascending turn stage and the descending & landing stages.Compared with the placebo,flight performance was significantly increased after the third administration of modafinil.Numbers of errors during 48 h SD and at 1:00～7:00 of the third day in modafinil group was 19% and 40% lower than those in placebo group respectively.Conclusion Simulated flight performance during 48 h SD is significantly improved after repeated administration of modafinil,especially when the impacts of SD and the circadian trough are combined.
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Objective To observe the effects of repeated +10 Gz stress on cerebral lipid peroxidation,liver and renal function in rats and the prophylactic effects of antioxidant tea polyphenols(TP).Method Twenty-four male Wistar rats were randomly divided into three groups(n=8 each):group A(control),group B(+10 Gz),and group C(TP).Group B and C were exposed to repeated +10 Gz stress(each for 30s,onset rate about 0.5 G/s,3 times/d with +1 Gz 1 min intervals,3 d/wk,4 weeks in total),but group A was only submitted to +1 Gz.TP(200 mg/kg) was given orally in group C about 1 h prior to the +Gz experiment,while distilled water was given in group A and B.Lipid peroxidation in the brain,liver and renal functions and serum lipids were determined.Results As compared with the control,lipid peroxidation in rat cerebral homogenate,mitochondria and cytoplasm was significantly increased( P<0.05),and serum creatinine concentration was markedly elevated after repeated +10 Gz stress(P<0.01).But,TP had significant inhibitory effect on +10 Gz stress induced peroxidative injury in rat brain and reduced the serum creatinine level.There were no differences of serum triglyceride and total cholesterol concentrations and glutamic-pyruvic transaminase activity among the three groups.Conclusion These results indicated that repeated high +Gz stress could bring about peroxidative injury in brain and harmful effect on renal function,and natural antioxidant TP had signficant protective effects.
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Objective To observe the effects of tea polyphenols (TP) on cardiac function and myocardial ultrastructure in rats after repeated +10 Gz stress. Method Twenty four male Wistar rats were randomly divided into three groups (n=8 each): group A (control), group B (+10 Gz), group C (+Gz with TP). Group B and C were repeatedly exposed to +10 Gz (each for 30 s, onset rate about 0.5 G/s, 3 times/d with +1 Gz 1 min intervals, 3 d/wk, 4 weeks in total), but group A was only submitted to +1 Gz. TP(200 mg.kg-1) was given orally to group C about 1h prior to the +Gz experiment, and distilled water was given to group A and B.Function of isolated rat working hearts and myocardial ultrastructure were observed. Result A significant decrease of left ventricular systolic pressure (LVSP) and injury of myocardial structure in rats were demonstrated after repeated +10 Gz stress. But TP could remarkably elevate the LVSP and improve myocardial ultrastructural injury in +10Gz stressed rats. Conclusion These results indicated that repeated high G exposure may produce cardiac structural and functional injuries in rats which might be partly related to free radical metabolism; and antioxidant TP had significant protective effects on the hearts of +Gz stressed rats.