Objective To investigate and compare the biomechanical stability between anatomical and overlapping reconstruction of the greater tuberosity in cadaveric humeral head replacement model. Methods Eight pair (16) fresh-frozen shoulder cadavers were match-paired into 2 groups. Four-part fracture model was created in all cadavers. Standardized humeral head replacement procedure was carried out in all specimens, and anatomical and overlapping reconstruction of the greater tuberosity was applied to each group respectively. Custom mounting apparatus and fixation jigs were designed for designated shoulder motion. A Binocular 3D Computer Vision metrical method was employed to measure the displacement of greater tuberosity relative to the humeral diaphysis. Results When the shoulder was external rotated to neutral position, the mean displacement of greater tuberosity in anatomical reconstruction group was (1.81?1.75) mm,while the mean displacement was (3.23?2.91) mm in overlapping group. Statistical difference was found between the 2 groups. When the glenohumeral joint was elevated to 30? and 60? forward flexion, the mean displacement of greater tuberosity in anatomical group was (4.01?5.00) mm and (5.99?6.97) mm respectively, while the mean displacement was (3.02?5.27) mm and (6.97?7.00) mm respectively in overlapping group. No statistical difference was found between the 2 groups during forward flexion measurement. Conclusion In cadaveric humeral head replacement model, anatomic greater tuberosity reconstruction shows better mechanical stability compared with overlapping reconstruction during external rotation to neutral position. This result suggests that there may be some loss in mechanical stability in overlapping fixed greater tuberosity. Even though standardized postoperative rehabilitation protocol are strictly followed, evident displacement of the greater tuberosity was detected. Postpone of the postoperative rehabilitation program after humeral head replacement for a decent period of time may benefit tuberosity healing.

Objective To study the best combination of respiratory parameters that can maintain good ventilation with a low airway pressure under general anesthesia and CO2 pneumoperitoneum (12 mm Hg) during laparoscopy, which is important for lung protections. Methods Basic respiratory parameters of anesthesia machine, respiratory frequency (f), tidal volume (VT), and respiration ratio (I∶E), were used as three factors A, B, and C. The there levels were set as f=15, 12, and 9 bpm; VT =8, 10, and 12 ml/kg body weight; and I∶E =1∶2.5, 1∶2.0, and 1∶1.5. L9(34) K=3 was adopted for repeated orthogonal experimental design. The effect of different combinations of respiratory parameters on peak inspiratory pressure (PIP), mean airway pressure (Pmean),and end-tidal carbon dioxide partial pressure (PETCO2), were analyzed statistically. Results During the laparoscopy, the vital signs of 27 patients were stable under general anesthesia with 9 combinations of the respiratory parameters, the SpO2 was maintained at 100%, and the PEEP was kept at 1 hPa. The effect of the three levels of VT (factor B) on PIP was not significant (P=0.074). While the effects of f (factor A) on PETCO2 and I∶E on Pmean were significantly different among the three levels (P=0.002 and P=0.017, respectively). Conclusion The best combination of three factors-levels respiratory parameters is not small tidal volume with fast frequency or large tidal volume with slow frequency, but is A2B2C2 (f=12 bpm, VT=10 ml/kg body weight, and I∶E=1∶2.0).

Objective To compare the results of locking intramedullar nail and Locking plate in treating proximal humerus fractures and discuss features of each instrument. Methods A total of 54 patients with fresh two-part surgical neck fracture of proximal humerus were divided into intramedullar nail fixation group(26 patients)and locking plate fixation group(128 patients).with no statistical difference upon age,gender and dominate hand involvement in two groups.At final follow-up,physical examination and X-ray films were used to evaluate fracture healing of shoulder ioint.In the meantime,VAS score,ASES score,Constant-Murley score,UCLA and SST questionnaire were used to evaluate the function of the shoulder in two groups. Results All fractures were healed basically within 8 weeks postoperative-ly.No infection or av&scular necrosis were fouml during follow-up.The incidence rate of complication in locking plate fixation group was higher than that in intramedullar nail fixation group.Both groups obtained satisfactory functional recovery of shoulder ioint.There was no statistieal difference in regard to active for-ward elevation,external rotation besides body,active height of internal rotation,Constant-Murley scores,and SST scores in both groups.The average ASES score and VAS score of locking plate fixation group was significantly better than those of intramedullar nail fixation group. Conclusions Both fixations can treat surgical neck fractures of proximal humerus well.Locking intramedullar nail causes less trauma to the patient while Locking plate has advantages in patients'final functional recovery.

Recurrent anterior shoulder instability is a common problem we have to deal with in clinic. With the progress in shoulder and elbow surgery, there have appeared many new concepts about the etiology, diagnosis and treatment of this disease. About 2 decades ago, people realized the important role of glenohumeral ligaments. Now we believe that the stability of the glenohumeral joint relies heavily on the congruent articulating surfaces and surrounding soft tissues that act as static and dynamic stabilizers. Many new methods, such as MRI, physical examination under anesthesia and arthroscopy, can help us diagnose the disease accurately. Moreover, substantial progress has been made in the treatment of anterior shoulder instability. Open Bankart repair has become the golden standard for the treatment. With the advance of techniques, however, arthroscopic stabilization of anterior shoulder instability can now achieve good results comparable with those of open surgery.

Objective To evaluate the results of delayed proximal humeral fractures treated by open reduction and internal fixation. Methods From January 2005 to July 2008, 26 patients with delayed proximal humeral fractures were treated by open reduction and internal fixation. There were 11 males and 15 females. The patients ranged from sixteen to 22-81 years old, with an average age of 49.3 years. The interval from injury to operation ranged 22 to 510 days, with a mean of 88 months. There were two-part fractue in surgical neck in 12 cases, two part in lesser tubercles of in one case,two part in greater tubercles in seven cases, three part in greater tubercles in three cases, four part in 2 cases and the splitting fracture in the head of humerus in one ease.The range of motion, VAS for pain, ASES (American sboulder and elbow surgeon's form) score, Constant score, UCLA (University of California-Los Angels scoring system)score and SST(Sim-pie Shoulder Test) for function evaluation were all recorded. The results were evaluated according to sex,age, injury side, operation times and combined injury by ANOVA.The correlation analysis was performed between operative time and results. Results The average forward flexion was 137.3°±35.1°, average exter-nal rotation was 28.9°±24.1° and internal rotation was T_(10). The mean VAS score was 0.7±1.2, the mean Constant was 83.1±17.9, the mean UCLA was 28.9±6.0, the mean SST was 8.7. There were no difference re-gaming sex, age, injury side, operation time and combined injury, fracture type and complications groups. No correlation existed between operative time and results. Conclusion It is very hard to treat delayed proximal humeral fracture due to high complication and demanding experience. With appropriate surgical technique, satisfactory results can be expected by open reduction and internal fixation.

The shoulder is a complex joint which consists of sternoclavicular joint, clavicle, acromioclavicular joint, scapula, glenohumeral joint,proximal humerus and scapulothoracic joint. It is important for us to have a good knowledge of the normal biomechanics of the shoulder when we treat shoulder problems. So this article intends to help its readers to get familiar with the characteristics of functional anatomy, biomechanics and motion of the shoulder under physiological condition.

Objective To investigate the influence of nebulized Pulmieort respules inhalation after endoscopic sinus surgery (ESS)on the expression of epithelial Na~+ channel(ENaC)protein in nasal mucosa. Methods Forty-four patients with nasal polyps undergoing ESS were randomly divided into Pulmieort respules treatment group(n=21,nebulized Pulmieort respules inhalation for 10 d after ESS)and Rhinocort control group(n=23,Rhinoeort aqueous nasal spray for 10 d after ESS).All the patients were performed biopsy of membrane on the residual middle turbinate 14 d after ESS,eosinophils (Eos)and neutrophils(Neu)per hundred inflammation cells were counted under microscope during ESS and after ESS,and the expression of ENaC protein was detected by immunofluorescence assay. Results The percentages of Eos and Neu decreased in two groups after treatment,and the percentage of Neu in Pulmieort respules treatment group was significantly lower than that in Rhinoeort control group(P<0.05).The expression of ENaC protein after treatment in Pulmieort respules treatment group was significantly lower than that in Rhinoeort control group(P<0.01). Conclusion Application of pulmieort respules after ESS can decrease Neu infiltration and inhibit expression of ENaC protein,which can relieve acute inflammation and edema of nasal mucosa.

Objective The purpose of our study was to report the results of using arthroscopic Remplissage and Bankart repair in patients who had an engaging Hill-Sachs lesion with significant glenoid bone loss. Methods We retrospectively reviewed 49 consecutive patients who underwent arthroscopic Remplissage and Bankart repair for anterior shoulder instability with a mean duration of follow-up of 29.0 months (24-35 months). At the time of surgery the mean age of 42 men and 7 women was 28.4 years. All patients were diagnosed as recurrent anterior shoulder dislocation with a bony lesion of glenoid and an engaging HillSachs lesion. An arthroscopic Remplissage and Bankart repair using metal anchor was performed in all cases.ASES score, Constant-Murley score and Rowe score were used to evaluate the stability and the function of the shoulder. Results Patients' active forward elevation significantly(P=0.007) improved from 162.9°±17.1°preoperatively to 170.9°±7.4° at final follow-up. The external rotation was 56.0°±17.6° before the surgery compared with the 54.1°±17.1° postoperatively(P=0.511 ). The ASES score, Constant-Murley score and Rowe score was 84.7±11.3, 93.3±8.7 and 36.8±8.5 preoperatively compared with 96.0±3.4, 97.8±3.6 and 89.8±12.5 postoperatively. Significant difference could be found with regard to ASES score (P=0.000), ConstantMurley score (P=0.005) and Rowe score (P=0.000). One redislocation happened and a subluxation was noticed in three patients (8.3%). Conclusion Arthroscopic Remplissage combined with Bankart repair can achieve satisfactory for recurrent anterior shoulder dislocation accompany with engaging Hill-Sachs lesion.

RESULTS AND CONCLUSION:(1)The number of apoptotic cels in rat condylar cartilage and subcondylar region: the sham operation group < the treatment group < the model group (alP< 0.05). (2)Expression of Bcl-2: The trend of the model group was lower than that in the sham operation group, although there was no statisticaly significant difference between the two groups; Bcl-2 expression in the treatment group was statisticaly higher compared to the model group (P< 0.05).(3)Expression of Bax and Caspase-3: The expression levels of Bax and Caspase-3 were higher in the model group than in the sham operation group (alP< 0.05), while Bax and Caspase-3 expression was lower in the treatment group than that in the model group (alP< 0.05). The results suggested that bisphophonates can regulate apoptosis in condylar cartilage from osteoporosis rats by changing the expression of Bcl-2, Bax and Caspase-3.

BACKGROUND: Diabetes mel itus is one of the most common systemic diseases, which often leads to the changes of the jaw and other bone structure, as wel as the abnormal changes of mineral metabolism. OBJECTIVE: To observe the three-dimensional structure and histopathological changes of the mandible in type 1 diabetes mel itus mice. METHODS: The mice were randomly divided into control group and diabetes mel itus group. The diabetes mel itus group received intraperitoneal injection of 50 mg/kg streptozotocin for 5 days to establish a type 1 diabetes mel itus model, and the control group received intraperitoneal injection of citrate buffer. RESULTS AND CONCLUSION: At 3 weeks after modeling, the micro-CT technique was used to observe the three-dimensional structure of the mandibles in the two groups. The quantitative analysis on the microstructure of cancel ous bone and cortical bone showed that the bone mineral density, bone volume fraction, trabecular number and trabecular thickness of cancel ous bone in the interest region in the mandible of type 1 diabetes mel itus mice were significantly decreased when compared with that in the control group (P < 0.01, P < 0.05), while the structure model index was increased significantly (P < 0.05); the mineral density and area of cortical bone were decreased in the diabetes mel itus group (P < 0.05). Hematoxylin-eosin staining showed that the number and volume of mandibular trabeculae of type 1 diabetes mel itus mice were decreased. The results suggest that the three-dimensional structure of the cancel ous bone and cortical bone in the streptozotocin-induced type 1 diabetes mel itus mice are changed significantly, and the microstructure change of the cancel ous bone is more obvious.