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Objective:To compare biomechanical stabilities between screw-plate fixation and non-cannulated screw fixation for Lisfranc ligament injury by a 3-D finite element analysis.Methods:A 3-D model of a healthy foot was developed from computed tomography images. The 1st and the 2nd dorsal tarsometatarsal ligaments and Lisfranc ligament were cut in the 3-D model of a healthy foot to establish a Lisfranc ligament injury model, in which screw-plate fixation (with 2 locking plates and 8 standard screws and one non-cannulated screw) and non-cannulated screw fixation (with 3 non-cannulated screws) for Lisfranc ligament injury were simulated respectively. Finite element analyses were carried out by Abaqus 6.14 software after loads were added in the 3-D models of screw-plate fixation and non-cannulated screw fixation for Lisfranc ligament injury. The overall stress-strain nephogram, the stress distribution and displacement of the foot bone, and the stress distribution on the internal fixation system were compared between the 2 kinds of models.Results:Under the same load, the stress of the whole screw-plate fixation was concentrated on the fixators, and the stress of the non-cannulated screws was also greater than that of the bones. In both models, the strain of the whole foot led to arch collapse, especially in the medial column. The maximum stress on the screw holes in the medial and middle columns in the screw-plate fixation model was 39.91 MPa, smaller than that in the non-cannulated screw fixation model (53.13 MPa). The relative displacement of the first metatarsal joint in the screw-plate fixation model was 8.515 × 10 -1 mm, much greater than that in the non-cannulated screw fixation model (3.893 × 10 -1 mm). Stress concentration was observed in both models. The stress of the screw-plate system was concentrated on the fibular side of the middle section of the plate used to fix the first tarsometatarsal joint, decreasing towards both ends. The maximum stress of the non-cannulated screws was located in the middle of the medial column screw for fixation of the first tarsometatarsal joint, significantly greater than those of the both ends. The maximum stress of the screw-plate system was 239.5 MPa, smaller than that of the non-cannulated screws (256.8 MPa). Conclusions:Non-cannulated screw fixation demonstrates a greater biomechanical stability for Lisfranc ligament injury than screw-plate fixation. However, the former may have a higher risk of screw breakage because it bears a greater stress.
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ObjectiveTo investigate the expression of miR-155 and miR-146a in peripheral blood mononuclear cells (PBMC) and plasma of rheumatoid arthritis (RA) patients.MethodsPBMC and plasma were separated from the peripheral blood of 34 RA patients and 15 healthy individuals.Total RNAs were isolated and miRNAs were purified.The levels of miR-155 and miR-146a were determined by quantitative reverse transcription PCR(qRT-PCR).U6 was used as housekeeping control.The amount of target miRNA was normalized relative to the amount of U6(ΔCt=ΔCtmiRNA-ΔCtU6).Relative expression levels were expressed as 2 △-ΔCt.Data were analyzed using SPSS 13.0 software.The test of homogeneity of variance and unpaired t-test was used to compare between groups.P values(2-tailed) less than 0.05 were considered as statistically significant.ResultsThe expressions of PBMC and plasma miR-155 were higher in RA patients than those in the healthy control individuals(0.08±0.08 vs 0.05±0.03,t=-2.225,P＜0.05; 5.9±6.7 vs 1.3±2.0,t=-3.677,P＜0.05).The expression of miR-146a in PBMC and plasma of RA patients and controls were(1.3±1.2 vs 0.8±0.6,t=-2.154,P＜0.05)and(741±1001 vs 300±295,t=-1.669,P＞0.05).According to their DAS28 value,RA patients were divided into high activity group (23 cases,DAS28≥5.0) and low disease activity group( 11cases,DAS28＜5.0).The plasma miR-155 and miR-146a expressions were significantly higher in high activity group than those in low activity group.There were no significant differences in the expression of PBMC miR-155 and miR-146a between the two groups.ConclusionThe expression of PBMC and plasma miR-155 and miR-146a are higher in RA patients.The expression of plasma miR-155 and miR-146a are associated with RA patients' activity.Plasma miR-155 and miR-146a may be potential non-invasive biomarkers for RA diagnosis anddisease activity assessment.
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Objective To analyze and explore the operative effect of coraccid process basilar part fractures combined injury of ligamental structure. Methods Use ilium-fascia lata complex tissue to reconstruct coronoid process of ulna and medial collateral ligament, recoverd anterior and wall horn anatomic structure of elbow joint. Total 9 cases of ulna coracoid process fractures concomitancy with elbow posterior dislocation . Among these one with olec-ranon fracture,five patients with head of radius fracture. Anterior trance joint approach was used,removal bone chips, restore defect with ilium-fascia lata complex tissue after cuting and trimming. Once reduction was achieved,fixed with screw. Repaird the collateral ligament and anterior joint capsule use the fascia lata, If there were combined fracture of the radius head or olecranon fracture,fixed through lateral approach,All injured extremities were treated with a posterior plaster splint with functional position for 3 weeks followed by elbow rehabilitation training. Results According to Moneys evaluation method,2 patients were classified as excellent ,5 as good,l as fair and 1 as poor. The excellent and good rate was 77. 8%. Two patients with gently ossifying myositis but no patients with wound infection,internal fixation loosening or break,elbow joint destabilizing orcorpus libemm. Conclusions Coracoid process basilar part fractures was simultaneous with the instability of osteal frame and soft tissue. To attain the favourable anatomical foundation for elbow joint functional recovery, it should rebuild the height and shape of coronoid process first and think highly of repair or rebuild medial collateral ligament and joint capsule. It reconstructed the coronoid process osteal frame and soft tissue instability at the same time to use ilium-fascia lata complex tissue. The operative procedure is simplify with reliability effect and fine functional rehabilitation.
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Objective To improve the operation method of rupture of Achilles tendon for decreasing complication. Methods Total 39cases with closed rupture of Achilles tendon were selected in this study. Short incision was made at achilles tendon wall, reveal and anneal the broken ends, using Kirschner wire and steel-wire to make rectangle frame ,intradermic fixation of fracture away from the broken ends, then sutured ends with rarities and smoothing,functional exercise after 6weeks ankle rest position fixation. Results According to the Arner Lindholm evaluation system,the treatment outcome were excellent in 34 cases ,and good in 5cases. No complication including re-rupture skin ,tendon necrosis and infection were found after operation. Conclusion Repaired closed rupture of Achilles tendon with short incision and rectangle frame, assisted with ankle rest position fixation after operation wasa worthy way for treating closed rupture of a chilles tendon.
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Objective To observe the application and efficacy of dynamic condylar screw (DCS) in treating intertrochanteric fractures of the femur and discuss the fixation principle, feasibility, advanta-ges and related issues. Methods A retrospective analysis was done on 23 patients with intertrochanter-ic fractures of the femur treated with DCS from January 2000 to December 2006. Of all, there were 10 elderly patients with different levels of various kinds of internal diseases and 13 young patients injuried by high-energy such as traffic accidents. According to Boyd' s classfication, there was one patient with type Ⅰ fracture, five with type Ⅱ , nine with type Ⅲ and eight with type Ⅳ. After a detailed pre-operative physical examination and targeted treatment, DCS fixation was employed for intertrochanteric fractures of the femur. Results A follow-up for average 18 months showed no death. Early complications occurred in three patients including two with pulmonary infection and one with urinary tract infection, who got cured after proper treatment. There was one patient with long-term complication, post-traumatic arthritis. All 23 patients got bone healing, with excellenee rate of 96% according to Harris criteria. There were no complications like breakage of nails, nonunion, eoxa yarn deformity, shortening or external rotation of the lower limb. Conclusions DCS has advantages of simple operation, reliable fixation and coincidence with biomechanical characteristics and hence is one of ideal methods for treatment of intertrochanteric frac-ture of the femur, especially for subtrochanteric fracture, contrary chanteric fractur, fracture involving large pyriform troehanteric and comminuted fractures of sub-trochanteric lateral os integumentale.
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Objective To investigate the relationship between estrogen levels and tenosynovitis in postm-enopausal women. Methods 74 cases of postmenopausal women,including 32 cases of tenesynovitis (group A),42 cases healthy postrnenopausal women for the control group (group B) were observed. 42 cases of normal menstruation women were taken as control group (group C). Results The estrogen level was (89.7066±126.7458) pmol/L in group A,(45.6768±30.6342) pmol/L in group B,and (626.7384±361.5348)pmol/L in group C,There is statistical difference between group A and group C (P<0.05). Conclusions Tenosynovitis incidence in postmeno-pausal women has no significant relationship with the level of estrogen change.