[Objective]To evaluate the interface biomechanical characteristics of a new kind of hydroxyapatite coating.[Method] Ten dogs underwent hermiarthroplasty of hip joint and were divided into 2 groups.One group was placed in Ti-6AI-4V femoral stem(Ti hip group),the second group was placed in HA-coated femoral stem(HA hip group).The second method was rod implant in condyles in both legs of each dog.Four matured dogs were selected.Eight Ti-6AI-4V rods(Ti rod group)were placed in lateral and medial condyle in left leg of each dog and eight HA-coated rods(HA rod group)were implanted in that of right leg of each dog.The dogs were sacrificed at 12 weeks after operation,and then the interface shear strength and imerface histological changes were evaluated.[Result]The Pust-out test showed that the average interface shear strengths of Ti hip group and HA hip group were(2.58?1.56)Mpa and(7.57?1.03)Mpa respectively.The interface shear strengths of HA hip group was significantly higher than that of Ti hip group(P

Objective To evaluate the biologic characteristics of a new type femoral stems either coated with gradient hydroxyapatite (HA) or additionally loaded with rhBMP-2. Methods Fifteen dogs were divided into 3 groups according to the implanted hip prosthesis. Each animal received hemiarthroplasty in the right hip with prosthesis made of pure Ti-6Al-4V femoral stem (Ti group), the new gradient HA-coated femoral stem (HA group) with 100 to 150 ?m hydroxyapatite coating, and the new gradient HA-coated femoral stem loaded with rhBMP-2 of 9 mg (BMP-HA group) respectively. The dogs were sacrificed at 12 weeks after operation, and labeled with tetracycline 3 of 30 mg/kg days prior to sacrifice, and then the histological changes of the tissue surrounding the prosthesis were evaluated. The radiographic examinations were taken before and after sacrifice. Results On radiographic examination, local radiolucent line around the prosthesis was observed only in one specimen in Ti group. The new bone formation was found both in HA group and BMP-HA group more obviously than in Ti group. Under microscopy, it was noted that this new gradient HA-coating was intact and no obvious biodegradation in most section, whereas a fibrous membrane was found in Ti group. The average rates of interface osteointergration in Ti group, HA group and BMP-HA group were 4.05%?7.66%, 71.04%?9.81% and 88.86%?6.56%, respectively, those of HA and BMP-HA group were significantly higher than that of Ti group (P

Objective To observe the effect of arthroscopic meniscectomy for symptomatic discoid lateral meniscus and the importance of early treatment. Methods Arthroscopic meniscectomy was performed on 29 patients (31 knees) with symptomatic discoid lateral meniscus. Partial meniscectomy was performed on 27 knees, subtotal meniscectomy on 4 knees with tear on the edge of meniscus. Results The operations on all 31 knees were successful without complications. The mean Lysholm score was 95.6 (87-100) during the follow-up, which was significantly higher than that before the operation (65.7, range 36-78; P

Objective To review the characteristics and outcomes of primary total hip replacement(pTHR) in patients with ankylosing spondylitis(AS). Methods Eighteen patients (26 hips) with AS underwent pTHR from January 1991 to September 2003 were reviewed retrospectively. Sixteen patients (24 hips) were followed-up. The mean duration of follow-up was 85 months (ranging from 23 to 169 months). All patients were evaluated using Harris score standardization. Results There were 15 hips with hip ankylosis( 57.7%). The average time of the operation was 167.4 minutes (ranging from 90 to 350 minutes),the average volume of bleeding in the operation was 773.9 ml (ranging from 300 to 2000 ml),the postoperative average drainage was 488.6 ml(ranging from 50 to 1130 ml). The rate of excellent and good was 87.5 percent. Conclusion The pTHR is a very effective treatment for patients with AS. The perfect rehabilitation care is one of the main factors influencing the outcomes of pTHR for patients with AS.

BACKGROUND: Acetabular cup orientation using a standard radiograph of the pelvis is quite common method to assess artificial hip replacement nowadays. Non-standardization of pelvic orientation affected accuracy of measurement results, and it is difficult to compare. OBJECTIVE: To make sure how pelvis tilting affect the anteveration of the cup and to elevate clinical accuracy and compare study comparability. METHODS: Designed a simulated acetabular cup with serial concentric circles which pass through the same polars and represent anteveration of 0°, 10°, 20°, 30°, 40°, Loaded the simulated acetabular cup at an inclination of 35°, 40°, 45°, 50°, 55° to6 cadaver pelves, Made the pelves tilt around the frontal axis and sagittal axis with 5° each time in a scope of+30°. Takestandard radiograph of the pelvis accordingly. Radiograph was photographed end frontal angle of dip was measured. RESULTS AND CONCLUSION: Pelvic tilt of about 1° causes measuring errors of anteveration 0. 61 °-0. 73°. The anteveration decreased at both acetabular cups when pelvic posterior tilt and at the acetabular cup that near the X-ray source as pelvic lateral tilt. The anteveration rose at both acetabular cups when pelvic anterior tilt and at the acetabular cup that away from the X-ray source as pelvic lateral tilt. During clinical evaluation, pelvic orientation effects on measurement results should be considered.

BACKGROUND:Previous studies have indicated that resistin stimulates a large set of chemokines in chondrocytes that are known to be important in inflammatory joint lesions.
OBJECTIVE:To further investigate the mechanism of co-regulation roles of transcription and post-transcription in the up-regulation of two chemokine genes CCL3 and CCL4 in chondrocytes in response to resistin.
METHODS:Human chondrocytes, T/C-28a2 and ATDC5 cels were cultured. The function of resistin on the chemokine genes, and the expression of C/EBPβ, nuclear factor-κB isoforms and chondrogenic specific miRNAs were tested by qPCR. The co-regulation of C/EBPβ and nuclear factor-κB was investigated by nuclear factor-κB inhibitor (IKK-NBD) and C/EBPβ inhibitor (SB303580) treatments, and subcelular localization was detected with or without resistin stimulation.
RESULTS AND CONCLUSION:Resistin could increase the expression of chemokine genes independently. Chondrocytes reacted in a non-restrictedly cel-specific manner to resistin; C/EBPβ inhibitor, nuclear factor-κB and some chondrogenic specific miRNAs in a combinatorial manner regulated chemokine gene expression. The activity of C/EBPβ was augmented by a transient increase in activity of nuclear factor-κB, and both transcription factors acted independently on the chemokine genes, CCL3 and CCL4.