BACKGROUND:Posterior dislocation after total hip replacement is one of the most common complications that second only to loosen, and can affect the stability of the hip joint seriously. There is controversy on the effect of femoral head diameter and acetabular anteversion on the stability of hip joint in clinical study. OBJECTIVE:To investigate the effect of the femoral head diameter and acetabular anteversion on the stability of hip joint after hip prosthesis replacement. METHODS:The femoral head diameter and acetabular anteversion that affect the posterior instability after hip prosthesis replacement were measured on the cadaveric bone. The acetabular shel was inserted at 0°-20° of anteversion at five degree intervals. The femoral heads with different diameters (28, 32 and 36 mm) were used for experiment, the internal rotation degrees to dislocation caused by hip at 90° flexion and 0° adduction and at 90° flexion and 30° adduction were recorded. RESULTS AND CONCLUSION:When the cup anteversion varied from 0° to 15°, there was an increase in the degree of internal rotation angle that could cause hip dislocation with the increasing of femoral head diameter (P<0.05). When the cup anteversion varied from 15° to 20°, the increasing trend was not significant. With the hip at 90° flexion and 0° adduction, and the cup anteversion varied from 15° to 20°, the stability of 36 mm group was significantly higher than that of the 28 mm and 32 mm groups (P<0.01);the stability of 32 mm group was higher than that of 28 mm group when the acetabular anteversion in 10° or more (P<0.05);there was no significant difference in stability between groups when the anteversion less than 10°. With the hip at 90° flexion and 30° adduction, the stability of 36 mm group was significantly higher than that of the 28 mm and 32 mm groups (P<0.01);the stability of 32 mm group was higher than that of 28 mm group when the acetabular anteversion in 10° or more (P<0.05);there was no significant difference in stability between groups when the anteversion less than 10°. The results indicate that the increasing of acetabular anteversion can reduce the occurrence of dip dislocation, but when it is difficult to choice the acetabular anteversion, large-diameter femoral head is preferred to increase the stability of hip joint.

Objective To study the effects of Danhong Granule on blood rheology of blood stasis rats,and further to investigate the mechanism of promoting blood circulation and removing blood stasis.Methods 60 SD rats were selected and randomly divided into 6 groups,namely,normal control group,model group to the capacity of 0.5％ sodium carboxymethyl cellulose (CMC-Na),Danhong granules in high dose group (3 g/kg),Danhong granules dose group(1.5 g/kg),Danhong granules low dose group(0.75 g/kg),and compound Danshen dripping pill group(3 g/kg).Each group received gastric lavage at 1 ml/kg volume,1/d,for 7 days.After the last administration,the rat model of blood stasis was reproduced by subcutaneous injection of high dose epinephrine with ice water bath method.The effects of Danhong granules on blood rheology of blood stasis model rats were studied.Results Danhong granules in high dose group and compound Danshen dripping pills could reduce blood stasis model rats in blood viscosity (high shear,cut and low cut values were:Danhong granules in high dose group were(5.69±0.16)mPa·s,(6.97±0.48)mPa·s,(22.56±1.69) mPa·s; Compound Danshen Dropping Pill group (5.71 ± 0.24) mPa·s,(7.04 ± 0.51) mPa·s,(22.63 ± 1.64) mPa·s,plasma viscosity respectively:Danhong granules in high dose group were (1.43 ±0.03)mPa·s,compound Danshen dripping pill group(1.42±0.03)mPa·s,RBC (hematocrit value were:Danhong granules in high dose group were (0.42± 0.027) L/L,compound Danshen dripping pill group (0.41 ± 0.032) L/L; Danhong granules dose group could significantly lower the blood stasis model rats in blood viscosity (high,low cut)value (5.95 ± 0.37) mPa·s,(23.45 ± 1.57) mPa·s,plasma viscosity(1.47 ± 0.02)mPa·s and RBC hematocrit value (0.48 ± 0.029) L/L low dose group; Danhong granules low dose group could reduced blood stasis model rats obviously in blood viscosity (high shear,cut and low shear),plasma viscosity and hematocrit values of RBC [respectively:the whole blood viscosity in(7.15±0.41)mPa · s,(7.86±0.36)mPa · s,(28.68±1.69)mPa · s,(1.67±0.03)mPa · s,(0.50±0.033)L/L].Conclusion Danhong Granule can reduce the blood stasis model rats in blood viscosity (high shear,cut and low shear),plasma viscosity and hematocrit value of RBC,by activating blood circulation,removing blood stasis and improving blood rheology.

Objective To investigate clinical outcomes and complications of isolated polyethylene liner exchange for revision total hip arthroplasty.Methods From April 1995 to December 2007,80 patients (93 hips) underwent revision total hip arthroplasty during which only polyethylene liner was exchanged with reservation of acetabular cup.There were 41 males and 39 females,aged from 27 to 82 years (average,53.3 years).The duration from the primary THA to the revision surgery ranged from 0.3 to 18.4 years (average,10.9 years).The reasons for liner exchange included:polyethylene wear with osteolysis (78 hips),polyethylene wear without osteolysis (5 hips),polyethylene wear with stem loosening (4 hips),recurrent dislocation (3hips),infection (1 hip),periprosthetic fracture (1 hip) and liner dislodgement (1 hip).Forty-seven liners were fixed into the old cup using cement,and 46 were fixed with the original locking mechanism.Sixty cross-linked polyethylene liners and 33 conventional polyethylene liners were used.Results All patients were followed up for 5 to 15 years (average,7 years).The average Harris hip score improved from preoperative 86.0±16.9 to 89.4±11.6 at final follow-up.Complications included dislocation (10 hips),infection (2 hips),periprosthetic fracture (1 hip) and liner dislodgement (1 hip).Ten hips underwent rerevision due to different reasons:cup exchange (5 hips),conventional polyethylene wear (2 hips),infection (2 hips) and liner dislodgement (1 hip).Using component loosening as the end point,the 10-year survival rate was 100％ in the cement fixation group and 84.8％ in the original locking group.Using rerevision as the end point,the 10-year survival rate was 90.4％ in the cement fixation group and 65.0％ in the original locking group.Conclusion Liner exchange either with cement or original locking mechanism is a safe and successful method.Highly cross-linked polyethylene has a higher wear resistance,which can reduce incidence of osteolysis and improve survival rate of prosthesis.

Objective To study the effects of Danhong mixture on platelet aggregation of rabbits.Methods 40 rabbits were randomly divided into 5 groups,8 rabbits in each group,of blank control group (treated with 0.5％ sodium carboxy methyl cellulose of the same volume),Danhong mixture of 5,2.5,1.25 g/kg group,aspirin group (treated with 0.025 g/kg aspirin).Each group was performed gastric lavage according to the ration of lml/kg,once daily,for continuous 8 days.Blood was obtained from heart 1 hour after last administration,then adenosine diphosphate (ADP),collagen,arachidonic acid (AA) were used for platelet aggregation test.Results Inhibition rate of Danhong mixture (5,2.5,1.25 g/kg) on ADP induced rabbit platelet aggregation were 9.4％,5.1％,and 0.6％ respectively,on collagen induced platelet aggregation were 34.5％,11.1％,and 5.6％; on AA induced platelet aggregation were 21.4％,11.6％,and 2.3％ respectively.Conclusion Danhong mixture had inhibitive action on platelet aggregation.

Objective To observe analgesic and croton oil-induced ear swelling effect of Chinese pine node.Methods Acetic acid writhing method and water tail-flick method was used to observe the analgesic effect,croton oil-induced ear swelling method was used to research anti-inflammatory effect.Results The inhibition rate of 1.0 g/kg,0.5 g/kg,0.25 g/kg of Chinese pine node on mice writhing response induced by acetic acid was 54.0％,44.3％,38.1％,and the inhibition rate on croton oil-induced mouse ear swelling was 48.4％,14.7％,7.4％.But no obvious influence on mice water tail-flick pain threshold.Conclusion Chinese pine node has anti-inflammatory and analgesic effects.

ObjectiveTo observe the effect ofHaizao-Xiangsheng mixture on signs and symptoms, blood index and tissue pathology of rabbit models with chronic pharyngitis.Methods60 Japanese white rabbits by random grouping method were divided into normal control group, model group, positive control group andHaizao- Xiangsheng mixture with high, medium and low dose group, with 10 rats in each group. Except the normal control group, rabbits in other groups were performed spraying ammonia in pharyngeal portion and submucosal injection of turpentine oil preparation to create chronic pharyngitis models. TheHaizao- Xiangsheng mixture, high, medium and low dose group were treated withHaizao-Xiangsheng mixture of 42, 21, 10.5 g/kg, the positive control group was treated with watermelon frost Runhou tablet suspension 5.04 g/kg, the normal control group and model group were treated with the same volume of saline. Animal signs and symptoms were recorded daily (including general conditions and temperature). After continuous administration of 7 days, red blood cell count (RBC), white blood cell count (WBC), percentage of neutrophils (N%), the percentage of mononuclear cells (M%) and percentage of lymphocytes (L%) were detected to observe the histological change of pharyngeal mucosa and lower tissue pathology.ResultsAfter administration, compared with the model group, high dose group ofHaizao-Xiangsheng mixture rabbit body temperature dropped (38.90 ± 0.21℃ vs. 39.23 ± 0.39℃,P< 0.05), WBC (10.1 ×1012/L ± 1.73 ×1012/Lvs. 13.1 ×1012/L ± 1.69 ×1012/L) decreased, and RBC increased (5.73 ×109/L ± 0.59 ×109/Lvs.5.19 ×109/L ± 0.43 ×109/L,P<0.01).ConclusionsHaizao-Xiangsheng mixture can improve signs and symptoms, hematology indexes and histopathological changes of the experimental rabbit models of chronic pharyngitis.