Objective To compare the influence of autologous and allogenic bone marrow stromal cells for repairing meniscal injury in avascular zone. Methods Forty New Zealand white rabbits were evenly divided into group A and B. The bone marrow stromal cells from group A rabbits were cultured and mixed with fibrin glue, forming graft. In group A, the graft was implanted into the meniscal injury zone in one side of the knees(autograft group), and only fibrin glue in another side(fibrin glue group). In group B, the graft was implanted into one side of knees (allograft group), and nothing was implanted into contralateral knees(control group). The rabbits were sacrificed 1, 2 and 3 months after surgery, and morphological study was done. Results In the autograft group, fibrous tissue containing a great deal of fibroblast appeared in the injured zone after 1 month, a large number of chondrocytes with formation of collagens were seen after 2 months, and the injuries healed up with fibrous cartilage after 3 months. In the control group, no healing was seen until 3 months. In the fibrin glue group, fibrous tissue was seen with a few fibroblasts, forming scar healing, but no chondrocyte. In the allograft group, the morphological appearance was similar with the autograft group. However, a large number of lymphocytes were seen in reparative tissue. Conclusion Transplantation of bone marrow stromal cells can promote the healing of meniscal injury in avascular zone. Though the allograft of bone marrow stromal cells may induce rejection, its occurrence rate is lower. The allograft for repairing the meniscal injury is worthy of further study.

Objective To observe the treatment effect of transplanted autogenous bone marrow stroma cells (BMS-C) absorbed in the type-Ⅰ collagen matrix in bone repair. Methods Thirty-two adult white New Zealand rabbits were randomly divided into Group Ⅰ and Group Ⅱ. The bone marrow was extracted from tubercle and greater trochanter of femur for culture. Then, the cells were amplified, implanted into type-Ⅰ collagen matrix and further cultured for two weeks. Two weeks later, the cells were implanted into the 1.5 cm radius defect. In the Group Ⅰ, management A (BMS-C+type-Ⅰ collagen) was given to the defect of one radius and management B (control) to the defect of the contralateral radius. In the Group Ⅱ, the defect of one radius was given management A and the defect of the contralateral radius management C (type-Ⅰ collagen).The rabbits were killed 8 and 12 weeks after implantation, the effect of three managements was compared. Results Twelve weeks after implantation, in the management A, all specimens had complete bony union; and in the management B, the specimens were filled with fibrous tissues; in the management C, a little scar formed. Conclusions BMS-C absorbed in the type-Ⅰ collagen can effectively repair bone defect.

BACKGROUND:Bone marrow stromal stem cells(BMSCs)do not allow for single differentiation of chondrocytes due to their multi-directional differentiation,bone morphogenetic protein secreted from osteoblasts affect the non-differentiated precursor cells and promote their osteoblast differentiations,while those differentiated cells are bound to form tissues.OBJECTIVE:To in vitro induce canine BMSCs differentiate into chondrocytes,and to investigate the method and conditions of chondrocyte differentiation in vitro.DESIGN,TIME AND SETTING:Single sample observation was performed in the Laboratory of Tissue Engineering,Sun Yat-sen University between March 2005 and January 2006.MATERIALS:One male dog,aged 4 months,was involved to harvest BMSCs from the rib.METHODS:Rib BMSCs extracted from bone marrow of 2.0-3.0 mL were cultured in vitro. When cells reached a confluence at 8-11 days,trypsinization was conducted and then halted with L-DMEM synthesis culture solution containing 10% fetal bovine serum. Cellular suspension was collected and centrifuged,cells were rssuspended and incubated at a ratio of 1:3. The third generation of cells were cultured and amplified,10 μg/L basic fibroblast growth factor 2 mL was added to replenish culture medium twice,then 1 mg/L transforming growth factor β1 of 2 mL was applied to induce BMSCs differentiation into chondrocytes.MAIN OUTCOME MEASURES:Toluidine blue and alcian blue stains were applied to determine cartilage matdx secretion,immunohistochemistTy was used for the detection of cartilage specific Ⅱ collagen expression.RESULTS:After BMSCs were primarily cultured and subcultured in vitro,they were shown to grow well at the fourth generation,those induced by basic fibroblast growth factor and transforming growth factor β1 were positive for toluidine blue and aician blue staining;immunohistochemistry showed a positive outcome for type Ⅱ collagen,indicating the induced BMSCs exhibited chondrocyte's characteristics.CONCLUSION:Utilizing basic fibroblast growth factor and transforming growth factor β1,the induced canine BMSCs could differentiate into chondrocytes,which is considered as an ideal seed cells for cartilage tissue engineering.

BACKGROUND: The meniscal allograft transplantation has been proved good outcome in clinical, however, the source and matching restrict its application. By means of a patent technique of separating antigen, a new biological meniscus can be obtained.OBJECTIVE: To observe the histological changes of transplanted biological meniscus in goat's knee joint, in addition, to investigate the feasibility of reconstituting meniscus by using biological meniscus. DESIGN, TIME AND SETTING: The animal experiment of goats was performed at the Central Laboratory in the Third Affiliated Hospital of Sun Yat-sen University between June 2005 and June 2006.MATEAIALS: A total of 15 healthy goats were used in the experiment. Fresh porcine meniscus was harvested for the preparing of biological meniscus.METHODS: The medial meniscus of goat was excised, and then the absent part was repaired using biological meniscus. MAIN OUTCOME MEASURES: The animals were sacrificed at months 1, 3, 6 and 12 after operation. And the samples were detected by histology, scanning electron microscopy (SEM) and Indian ink perfusion. RESULTS: The incision of all animals healed well, without infection or death. The transplanted meniscus healed well with the surrounding tissue, and the connection was tight. With time prolonged, the transplanted meniscus slowly soaked, and live cells existed inside the meniscus, but there were no live cells in about 1/4 district at 1 year after the surgery. Indian ink perfusion showed that the surrounding tissue grew inside and set up microcirculation, but only limited to 10% periphery of the meniscus (normal goat approximately 15%). The transplanted meniscus began the necrosis at 6 months after surgery. Under SEM, the surface of the meniscus became crude and cracked in some places, but still maintains the gross shape at 1 year after the surgery.CONCLUSION: There is no obvious rejection after the biological meniscus was transplanted into knee joint of goats. During the process of absorption, autologous tissue of goats can grow into and set up microcirculation in the transplanted meniscus. The transplanted meniscus protects the'knee cartilage notably, only slightly damage in cartilage can be observed.

[Objective]To determine the incidence and factors associated with pyrexia after total knee replacement(TKR).[Method]A retrospective review of 200 patients in departments of orthopaedics of our hospital and West China hospital who underwent TKRs from August 1998 and April 2006 was performed.The clinical,surgical and follow-up data were abstracted from the patients' records and were analyzed with SPSS 12.0.[Result]There was a statistically significant increase of the mean temperature post-operations,which remained significant throughout the first 7 days after surgeries(P

[Objective]To study the effects of AO double plates in internal fixation of humeral intercondylar fractures and to analyze the causes of the disfunction in elbow.[Method]From March 2001 to March 2006,21 cases (male 14, female 7) of humeral intercondylar fractures were reviewed, with an average age of 35.3 years (ranged,15～64 years).Left elbow:9 cases;right elbow:12 cases.According to AO/ASIF classification,type C1∶6,type C2∶10, and type C3∶5,2 cases of all were open fractures. Posterior operating approach of elbow: trans-olecranon osteotomy or trans-triceps-side approach and internal fixation by standard method of AO double plates were performed in all cases.The patients began the active training of elbow joint as soon as possible postoperatively.[Result]Twenty-one cases were followed up for 8～38 months and the average time was 14.8 months.Bone union was obtained in all cases.One case complicated wound infection,it recovered after 3 weeks of dressing.And 1 case complicated with radial nerve injury,which recovered with neural nutrients.According to the Cassebaum scoring system,the effects were evaluated as excellent 7,good 10,and fair 4,and the excellent-good rate was 80.9%.[Conclusion]The application of AO double plates was proved to be a good method to treat humeral intercondylar fractures at present. But the severity of the bone comminution and soft-tissue lesion, the effective fixation,earlier active exercise were the main causes that influence the functional recovery of elbow joint.

[Objective] To evaluate the cellular biocompatibility of the nano poly(L-lactic acid)-block-poly(?-caprolactone)(Nano-PLLA-b-PCL)with canine articular cells and its feasibility as a scaffold for the cartilage tissue engineering.[Methods]Nano-PLLA-b-PCL was made by liquid-liquid phase separation.Canine articular cells were isolated and multiplied in vitro.The passage 3 cells were seeded onto the PLLA-b-PCL films and cultured in the 2-dimensional environment.The cytotoxicity was measured with MTT assay.Cellular Morphological changes were observed by phase-contrast microscopy and Hoechst33342 fluorometric method.Another passage 3 cells were seeded onto the Nano-PLLA-b-PCL scaffolds(experiment group),PLLA-b-PCL scaffolds(control group)and cultured in the 3-dimensional environment for 3 weeks.The ratio of cell adhesion was detected by cell counting method.The morphological changes of cells were observed by scanning electron microscopy.The protein content in seeded cells were determined by bioinchoninic acid assay(BCA).The content of DNA was quantified using Hoechst33258 assay.[Results]MTT assay showed the PLLA-b-PCL had no cytotoxicity.The seeded cells adhered and proliferated well into the Nano-PLLA-b-PCL scaffolds,and they maintained good cell phenotype.After 21-day cell culture within the Nano-PLLA-b-PCL scaffolds,the chondrocyte DNA and protein contents increased with time.Moreover,the content of DNA and protein was higher in the experiment group than that in the control group,respectively(P

Objective To evaluate graft isometry after anatomic single bundle reconstruction of anterior cruciate ligament (ACL) using dynamic computed tomography (CT).Methods A retrospective study was conducted of the 14 patients who had undergone single bundle ACL reconstruction from June to August 2015.They were all men,with an average age of 28.6 years (range,from 18 to 39 years).At 6 months after operation,they received dynamic CT scanning during a cycle of knee extension to flexion.3D bone models representing the knee at different flexion positions (0°,30°,60°,90°,and 120°) in each patient were reconstructed from the CT images.The grid method was used to locate the positions of the central footprints of the tibial and femoral tunnels.The lengths between the entries of the femoral and tibial tunnels were measured from each tunnel entry to reflect the graft length change.Furthermore,we measured the isometry at the over-the-top position of the femur and at the anatomic tibial position.Results All the tunnel entries were located at the central area of the ACL anatomic attachment.The reconstructed ACL was the longest when the knee was in full extension.The length was gradually shortened between the femoral and tibial tunnels during flexion of the knee from 0° to 90°.The anatomic position showed an average of 4.82 mm shortening and the over-the-top position an average of 3.28 mm shortening.The length excursion increased in early flexion from 0° to 30° (2.91 ±0.91 mm on average) and reduced in later flexion from 90° to 120° (2.98 ± 1.41 mm on average).Conclusions None of the reconstructed ACL was isometric.A graft length may be the longest when the knee is in full extension and decrease gradually during the flexion from 0° to 90° and increase gradually during the flexion of 90° to 120°.The graft should be fixed when the knee is in the flexion of 30°.

BACKGROUND: Presently-used artificial intervertebral disk is different greatly from the normal physiological intervertebral disk in structure, material and biological properties and so on. Therefore, stress conduction at corresponding spinal section will have a certain change after the implantation of artificial intervertebral disk.OBJECTIVE: To investigate the stress distribution in small joints of normal intervertebral disk group, vertebral extirpation group and artificial lumbar intervertebral disk group with three-dimensional element method in order to discuss exploratorily the influence of the implantation of artificial lumbar intervertebral disk on the stress distribution in small joints.DESIGN: Observative and comparison experiment.SETTING: Orthopedic Department, Third Affiliated Hospital and Second Affiliated Hospital, Sun Yat-sen University; Biomechanical Laboratory in Southern Medical University.PARTICIPANTS: Spinal specimen collected from the healthy people who died in accidenct without any spinal illness (donated by their family member) was used to establish three kinds of three-dimensional element models of normal intervertebral disk, artificial intervertebral disk and vertebral extirpation as experimental subjects.METHODS: Finite element MSC.MARK software was used to establish normal intervertebral disk model with height of 10.00 mm, cross sectional area of 1300.00 mm2, and vertebral pulp cross sectional area of 495.8 mm2;in the model of vertebral pulp extirpation,the intrinsic pressure of vertebral pulp was zero; and in the three dimensional models of artificial lumbar intervertebral disk and L4-5 movement segment , the small joints were about 10.53 mm high with width of 13.37 mm and auricular area of 135 mm2.Then lumbar movement was simulated for the study of the stress distribution in small joint.MAIN OUTCOME MEASURES: Comparison of the stress in small joints under 6 kinds of states in the above three kinds of intervertebral disk movement model.RESULTS:In vertebral pulp extirpation group, the stress was proved to be the highest at superior edge, posterior middle part, lower edge and anterior middle part of small joints under anteflexion, backward extension, compression, lateroflexion and revolving states, moreover, small joint stress in artificial lumbar intervertebral disk was higher than that in normal intervertebral disk, but obviously lower than that in vertebral pulp extirpation group;however, the small joint of the middle part of artificial lumbar intervertebral disk bore the highest stress under revolving states.CONCLUSION: In contrast with vertebral pulp extirpation group, the small joint stress could be reduced after the implantant of artificial lumbar intervertebral disk, but was still higher than that of normal lumbar intervertebral disk group and the anti-verticity in artificial lumbar intervertebral disk group was markedly lower than that of normal lumbar intervertebral disk group and vertebral pulp ablation group, thus indicating that although presently-used artificial lumbar intervertebral disk possesses most of mechanical functions of normal lumbar intervertebral disk, but is still different from true lumbar intervertebral disk.

BACKGROUND: At present, there are very big differences in structure,material character and biological property between artificial intervertebral disc (AID) and normal physiological intervertebral disc.OBJECTIVE: Three-dimensional finite element method was used to observe and analysis the stress conduction of artificial lumbar intervertebral disc in lumbar motion segment.DESIGN: Single sample observation was designed.SETTING: Department of Orthopaedics, Third Affiliated Hospital, Sun Yat-sen University; Department of Orthopaedics, Second Affiliated Hospital, Sun Yat-sen University; Laboratory of Mechanics, Southern Medical UniversityPARTICIPANTS: It was to employ a vertebral sample without any spinal disorder of a healthy male died due to accidence and a finite element model of AID implantation in vertebral motion segment established with SB Charite Ⅲ AID.METHODS: According to industrial design chart of AID, finite element software MSC.MARK was utilized to establish three-dimensional model of artificial lumbar intervertebral disc. The corpus sample of motion segment of healthy lumbar vertebrae was collected and scanned with spiral CT machine and imaging documents were input in computer to preserve.Geometric model of L4-5 segment was established in three-dimensional coordinate system in ASC.MARK software. The intervertebral disc in L4-5 motion segment model was replaced by AID. It was to ensure the fixation of lower terminal lamina of L5 in the model. 4 Nm moment of force was exerted in anterior flexion, posterior extension, lateral bending and torsion on the sample successively. Finally, force of internodes representing AID was calculated and stress distribution was recorded.MAIN OUTCOME MEASURES: To observe stress distribution of anterior flexion, posterior extension, compression, lateral bending and rotation of AID.RESULTS: Finite element model of artificial lumbar intervertebral disc implanted lumbar motion segment that is in conformity with clinical practice was established. Stress distribution of AID was characterized as:er lamina was the maximum and that in the lower inclined part of slide of slide core and cover lamina was two or three times as same as that of sion, the stress in the center of slide core and cover lamina was the maximum.CONCLUSION: The finite element model of artificial lumbar intervertebral disc implanted lumbar motion segment established is in conformity with the structural character of practical artificial intervertebral disc in morphology, size and motion property, based on which, it is feasible to carry on the experiment on stress distribution of artificial intervertebral disc.