BACKGROUND: Treatment of large bone defects is an important problem faced by orthopedic physicians. Allogeneic bone transplantation is a classic method, but it has many restrictions. The membrane guided bone regeneration technique has become an important method for the research nowadays.OBJECTIVE:To compare the effects of self-made high strength biodegradable nano-hydroxyapatite/multi(amino acid) copolymer (n-HA/MACP) guided bone regeneration membrane tube and allograft bone graft segment in the repair of large segmental bone defect in goats. METHODS: The model of 30 mm large segment bone defect in the middle section of the femur in 32 adult goats was established. Experimental group used self-made n-HA/MACP tube to bridge defects following bone plate fixation. The control group was treated with allograft bone graft bone segments combined with plate fixation. The animals were sacrificed at 4, 8, 12 and 16 weeks after operation, and the bone callus growth was observed in the specimens. The X-ray and histological observations were performed at the same time. Biomechanical measurement of plate fixation of allograft cortical bone segment was done at 12 and 16 weeks after operation. RESULTS AND CONCLUSION: (1) After 4 to 16 weeks, gross and pathological results showed fibrous callus growth inside and outside of the membrane tube, and the fibrous callus gradually hardened into a bony callus. Additionally, the callus was larger in the experimental group than in the control group. X-ray films showed significantly increased lateral callus density in the experimental group as compared with the control group. (2) Maximum bending strength was significantly higher in the experimental group than in the control group at 16 weeks (P < 0.05). Overall, the n-HA/MACP membrane tube used for bridging large segment bone defects in goats can obtain similar repair effects to the allograft cortical bone, and further achieve the better mechanical strength of the new bone segment than the allograft bone.

BACKGROUND:Bisphosphonates that can suppress osteoclast activity strongly is a powerful inhibitor for bone resorption, which has been reported to have good effects in the treatment of fibrous dysplasia.
OBJECTIVE:To evaluate the clinical effect of surgical treatment combined with bisphosphonate therapy in the treatment of fibrous dysplasia.
METHODS: Fifteen patients with fibrous dysplasia of the long bone were subjected to surgical treatment and oral bisphosphonate therapy postoperatively. Limb pain, limb function, local X-ray manifestations and blood alkaline phosphatase activity were observed before and at 3, 6, 12, 24 months after treatment. The therapeutic effects were evaluated using modified Macnab standards.
RESULTS AND CONCLUSION:Al the 15 patients were folowed up for more than 24 months, and their pain symptoms were significantly relieved after the combined treatment of surgery and bisphosphonates, excelent in 12 cases and effective in 1 case, and the total efficiency was 100%. X-ray films showed that the density slightly decreased in operation areas after 3 months, but at 6 months after treatment, the cortical bone was thickened and the marrow cavity density increased in the operation areas, and non-focal zone was continuously enlarged. No fractures and recurrence were found in al patients. At 6 months after treatment, the serum alkaline phosphatase activity decreased significantly (P < 0.05). The results suggest that surgical operation with bisphosphonate treatment for bone fibrous dysplasia can effectively inhibit the bone resorption, promote bone formation, increase the intensity of the lesion, reduce fractures and recurrence rate, so as to achieve a better therapeutic effect in clinic.

Obej ctive Knockout mice are widely used in the studies of joint diseases .This article investigated the effects of joint processing methods , collagenase types ,and collagenase digestion time on the number of primary fibroblast -like synoviocytes (FLSs) obtained from mice. Methods The hind legs of 6 of the 12 male mice were cut open from the hip joints , but not those of the other 6.FLSs were isolated using the type-Ⅳcollagenase digestion method and purified by differential digestion .Cell morphology was observed under the inverted microscope .The type, viability, and purity of the cells were determined by flow cytometry . Rse ults Significantly fewer FLSs were obtained from the mice with the hind legs cut open ( 19 133 ±115 ) than from those without (24 933 ± 503) (P<0.05).The numbers of FLSs collected from the cell suspension at 1, 2, 3, 4, 5,6 , and 7 hours after digestion were 700 ±300 , 600 ±100 , 15 200 ±900 , 5100 ±800 ,2700 ±300 , 900 ±200, and 300 ±100, respectively, the highest at 3 hours. There were statistically significant differences in the total number of FLSs obtained by type-Ⅳ and type-Ⅱ collagenase digestions (24900 ±500v s 18 100 ±400, P<0.05). Conclusion For in virt o culture of primary mouse FLSs, it is recommended that the hip joints be not cut open, and type-Ⅳcollagenase be used with cell sus-pension at 2-6hours after digestion .

Objective:To compare the diagnostic value of three quantitative evaluation methods based on three-dimensional rapid fluid attenuation inversion recovery sequence (3D-FLAIR) vein-enhanced labyrinth images in endolymphatic hydrops.Methods:From October 2017 to April 2019, a retrospective study was conducted on 86 patients with unilateral otogenic vertigo who were admitted to Beijing Tongren Hospital, Capital Medical University. MRI was performed 8 h after the single-dose Gd-DTPA intravenously injection in all patients. Three evaluation methods were used to calculate the ratio of the endolymphatic area to the total lymphatic area, the ratio of the saccule to utricle area, and the ratio of the endolymphatic volume to the total lymphatic volume, respectively. The paired t test was used to compare the three ratios between the affected and healthy ears. With clinical diagnosis as the gold standard, the receiver operating characteristic (ROC) curve analysis was used to analyze the efficacy of three methods in diagnosing endolymphatic hydrops. Results:Totally 65 cases were finally diagnosed endolymphatic hydrops clinically. There were statistically significant differences of all the 3 ratios between the affected and healthy ears ( t=9.93, 7.22, 8.20, all P<0.001). The ROC curve showed that the area under the curve (AUC) of endolymph/total lymph area ratio, saccule/utricle area ratio, endolymph/total lymph volume ratio for diagnosis of endolymphatic hydrops were 0.882, 0.768, 0.884 (all P<0.001). And there were no significant differences between each paired AUCs (all P>0.05). Conclusions:All three methods of endolymph/total lymph area ratio, saccule/utricle area ratio, endolymph/total lymph volume ratio can quantitatively evaluate endolymphatic hydrops. The endolymphatic/total lymphatic area ratio method is still the most convenient method at present.

Objective:To explore the clinical application value of each sequence by analyzing the characteristics of labyrinthine signal on MRI in patients with unilateral sudden deafness.Methods:Totally 52 patients of unilateral sudden deafness with inner ear MRI were analyzed retrospectively at Beijing Tongren Hospital, Capital Medical University from January 2016 to July 2019, all of which could find abnormalities in the labyrinth, including 17 cases of plain scan and 35 cases of enhanced scan, with sequences including plain T 1WI, enhanced T 1WI, plain and enhanced delayed 3D fluid attenuation inversion recovery (3D-FLAIR). The affected labyrinthine signal characteristics of each sequence were analyzed and the involvement sites were judged. The ability of each sequence to show labyrinthine abnormal signal was evaluated and scored. The Friedman test and Wilcoxon signed rank sum test were used to compare the subjective scores of the ability to show labyrinthine high signal in different sequences in plain and enhanced patients, respectively. Fisher′s exact probability method was used to analyze the relationship between the affected sites and the recovery of hearing, tinnitus and vertigo symptoms. Results:Fifty-two patients (100%, 52/52) showed labyrinthine high signal on T 1WI, 8 (15.4%, 8/52) showed higher signal and 3 (5.8%, 3/52) showed low signal on T 2WI. Thirty-five (100%, 35/35) showed high signal on enhanced T 1WI, among which 27 had enhancement (77.1%, 27/35). Fifty-two (100%, 52/52) showed significant high signal of the affected labyrinth on 3D-FLAIR (17 plain scan, 35 enhanced scan). The scores were 2 (2, 2), 3 (2, 3), 3 (3, 4) and 4 (4, 4) of T 1WI, enhanced T 1WI, plain and enhanced 3D-FLAIR respectively. The overall difference in subjective scores of plain T 1WI, enhanced T 1WI and enhanced 3D-FLAIR in enhanced patients was statistically significant (χ2=64.528, P<0.001), and the comparison between the two was statistically different (all corrected P<0.05). The plain 3D-FLAIR score was higher than the plain T 1WI in patients with a statistically significant difference ( Z=-3.729, P<0.001). Twenty-seven cases (51.9%, 27/52) exhibited high signal at the ampulla of semicircular canals, with a statistically significant difference in the distribution of hearing recovery or not ( P=0.001). Conclusions:Both T 1WI and 3D-FLAIR sequences can effectively identify the labyrinthine high signal, but the latter was better than the former of its ability to display, especially delayed enhanced 3D-FLAIR. The high signal at the ampulla of semicircular canals was a characteristic predictor of non-recovery of hearing.

BACKGROUND:"Tendon off-position"is a disease name included in the International Classification of Diseases 11th Revision,and also a clinical indication of manipulation,acupuncture and other treatments.However,its specific mechanism is still unclear.It is urgent to establish an animal model that can reflect the clinical and pathological characteristics of"tendon off-position,"so as to further study the mechanism of effective clinical treatments. OBJECTIVE:To establish an animal model of"tendon off-position"in rats based on isometric contraction of skeletal muscles,and to explore the changes of skeletal muscle function and morphological phenotype after"tendon off-position." METHODS:Sixty rats were randomly divided into control group,static-loading group and extra loading group,with twenty rats in each group.Rats in the control group were kept normally without treatment.In the latter two groups,the rats were fixed by the self-made static-loading modeling device and a static-loading(the body mass of each rats was applied as the static-loading)was applied to cause sustained isometric contraction of the upper limb muscles.Then,animal models of"tendon off-position"were successfully established.In the extra loading group,50%of the body mass was added to the ankle joint after modeling.The skeletal muscle samples were harvested at 2 and 4 weeks after modeling.The changes of limb grip strength,wet mass of skeletal muscle,and serum levels of creatine kinase-muscle and lactate dehydrogenase A were measured,and the changes of skeletal muscle histomorphology and ultrastructure were observed. RESULTS AND CONCLUSION:At 2 weeks after modeling,the rats in the static-loading group and extra loading group showed significantly decreased grip strength and wet muscle mass,significantly increased serum levels of creatine kinase-muscle and lactate dehydrogenase A,and abnormal muscle fiber morphology and structure accompanied by a large number of deposited collagen fibers.Electron microscopy results showed that the structure of myofibrils was disordered,the Z-line was distorted,and the light and dark boundaries were blurred.At 4 weeks after modeling,the grip strength of the model rats was increased compared with that at 2 weeks,the serum creatine kinase-muscle and lactate dehydrogenase A levels were decreased,and the changes of muscle fiber morphology and ultrastructure were recovered to varying degrees.It is suggested that the rat skeletal muscle injury model based on continuous isometric contraction of skeletal muscle can well reflect the pathological characteristics of"tendon off-position"at 2 weeks,and can be used to study the mechanism of acupuncture and manipulation in the treatment of"tendon off-position."