ABSTRACT
Objective:To investigate the therapeutic effect of rat bone marrow mesenchymal stem cells (BMSCs) transfected with recombinant rat platelet-derived growth factor BB (rrPDGF-BB) gene on the distraction osteogenesis.Methods:From October, 2019 to June, 2020, 48 batches of BMSCs were cultured from 48 young SD rats, 24 of which were transfected with rrPDGF-BB gene by lentivirus. Meanwhile, other 72 male adult SD rats were randomly selected to establish the right femoral distraction osteogenesis model. The rats were equally divided into 3 groups. PBS, BMSCs without intervention and BMSCs transfected with rrPDGF-BB gene were injected into the distraction space of each group of rats assigned as Blank group, Negative group and Experimental group, respectively. Results of the experiment were evaluated by means of imaging and immunohistochemistry. P<0.05 indicated a statistically significant difference. Results:The cultured BMSCs grew well. The expression of CD34(0.1%) and CD45(2.8%) in the third generation of BMSCs was low, and that of CD29 (95.1%) was high, which was consistent with the phenotype of BMSCs described in literatures. After transfection, the expression of green fluorescence gradually increased with the extension of transfection time, confirming the success of transfection. After 14 days, all rats reached the expected distance of distraction. The rats were observed at assigned time points in 2, 4 and 8 weeks. The photos of femur specimen showed that continuous callus could be seen in the experimental group, the hardness and colour were close to the normal bone tissue, and the activity of the distraction space was poor, which was lower than that of the blank group. X-ray examination showed that there were more new callus in the experimental group, and the bone marrow cavity was re-canalized earlier than that of the blank group; Micro-CT examination, in sagittal plane, showed that the distraction space of the experimental group healed well, the broken end was connected, and the recanalization of bone marrow cavity was earlier than that of the blank group; Micro-CT parameters of each group showed that trabecular thickness[(0.297±0.005) mm], trabecular number [(1.663±0.032) mm], bone volume fraction[(59.832±2.187)%] and bone mineral density[(0.586±0.014) g/cm 3] of the experimental group were the greatest, while trabecular separation[(0.399±0.051) mm] of the experimental group was the smallest. There was statistical difference between each group( P < 0.05); HE staining and VEGF immunohistochemistry showed that the vessels and chondrocytes formed earlier and were more in the experimental group than that in the blank group. In 8 weeks, the new callus joined into one piece under the microscope in the experimental group, and the bone marrow cavity was re-canalized with a large number of red blood cells. Conclusion:Studies have shown that BMSCs transfected with rrPDGF-BB gene can promote the formation of callus in the distraction area of rats, shorten the mineralisation time of new callus, and promote the maturation of new bone in the area of distraction osteogenesis.
ABSTRACT
Objective@#To evaluate the long-term functional recovery after contralateral 7th cervical nerve(C7) transfer with brachial plexus root avulsion and the effect on the contralateral limbs after operation.@*Methods@#A total of 83 patients with injory of brachial plexus avulsion were underwent contralateral C7 transfer from September, 2004 to December, 2014. Among them, contralateral C7 were transferred to the median nerve in 33 cases, to radial nerve in 14 cases, to musculocutaneous nerve in 22 cases, and simultaneous transfer to median and musculocutaneous nerve in 14 cases. The followed-up contents included recovery of muscular strength and sensory innervated by the recipient nerve, bilateral limbs synergistic activity and the effect on the contralateral limbs after the surgery.@*Results@#All 83 cases were successfully followed-up for 3.2-6.2 years (average, 4.5 years), and found no significant effect on function of the contralateral limbs. In the group of C7 transferred to the median nerve group, 10 cases had muscle strength recovered≥M3, and 26 cases had sensory recovered≥S3; In the group of C7 transferred to the radial nerve, 6 cases had muscle strength recovered≥M3, and 9 cases had sensory recovered ≥S3; In the group of C7 transferred to the musculocutaneous nerve, 12 cases had muscle strength recovered≥M3, and 17 cases had sensory recovered≥S3. In the group of C7 simultaneous transferred to the median and musculocutaneous nerve, 6 cases had muscle strength of wrist and digital flexion recovered≥M3, 5 cases had elbow flexion recovered≥M3, 9 and 10 cases had sensory of innervated area and lateral forearm region recovered≥S3, respectively.@*Conclusion@#Contralateral C7 transfer is an ideal procedure for the treatment of total brachial plexus root avulsion with definitive clinical outcomes.
ABSTRACT
To investigate the role of the bionic multi-channel nerve conduit by reducing mis-match of regenerated nerve fibers in the rabbit sciatic nerve defect. Methods The experiment was conducted from July, 2017 to February, 2019. A total of 55 New Zealand white rabbits were randomly divided into two groups (First group, n=30 and Second group, n=25).There were 5 subgroups (n=6) in the first group, which were autograft and cus-tom-anatomic nerve conduits (CANC) with different channel (1-CANC, 2-CANC, 3-CANC, 4-CANC) that implanted to repair the rabbit sciatic nerve defect (10 mm). The electrophysiological, triceps muscle wet weight recovery rate, histological study and ankle index analysis were used to evaluate the treatment of each group at 12 and 24 weeks postoperatively. There were 5 subgroups (n=5) in the second group. The simultaneous retrograde tracing method was applied to compare with the number of mismatched nerve fibers at 24 weeks postoperatively. All data were recorded and analyzed by One-way ANOVA method, the Turkey’s method was used to compare the differences between each subgroup. The difference was considered to be statistically significant if P＜0.05. Results The autograft group showed the best recovery in the electrophysiology, histology study and ankle index at 12 and 24 weeks postoperatively (P＜0.05).Histology results showed that the same number of myelinated nerve fibers in all CANC group (P＞0.05), but di-ameters of nerve fiber and myelin thickness were higher in 2-CANC and 3-CANC [(10.67±0.56) μm,(10.65±0.53) μm, respectively] compared with 1-CANC and 4-CANC groups [(8.43±0.63) μm, (9.03±0.55) μm, respectively].The differ-ences were similar in electrophysiological, wet weight recovery rate of triceps muscle, histological study and ankle index analysis.Simultaneous retrograde tracing showed that the autograft group had highest total number of labeled profiles, but no significant difference of the total number of labeled profile was showed among the CANC groups. However, the 1-CANC group[(7.1±2.4) %] showed highest percentage of the FB-NY-neurons than other CANC groups[(2.7±1.9)% in 2-CANC, (2.5±2.3) % in 3-CANC, and (2.2±1.2)% in 4-CANC](P＜0.05). Conclusion The autograft group showed the best results among all groups.Compared with the 1-CANC group, the 2-CANC and 3-CANC group obtained more mature regenerated nerve fibers and with a fewer mismatch rate.Moreover, that did not affect the number of regenerated fibers.
ABSTRACT
Objective To evaluate the long-term functional recovery after contralateral 7th cervical nerve(C7) transfer with brachial plexus root avulsion and the effect on the contralateral limbs after operation. Methods A total of 83 patients with injory of brachial plexus avulsion were underwent contralateral C7 transfer from September, 2004 to December, 2014.Among them, contralateral C7 were transferred to the median nerve in 33 cases, to radial nerve in 14 cases, to musculocutaneous nerve in 22 cases, and simultaneous transfer to median and musculocutaneous nerve in 14 cases.The followed-up contents included recovery of muscular strength and sensory innervated by the recipient nerve, bilateral limbs synergistic activity and the effect on the contralateral limbs after the surgery. Results All 83 cases were successfully followed-up for 3.2-6.2 years (average, 4.5 years), and found no significant effect on function of the contralateral limbs. In the group of C7 transferred to the median nerve group, 10 cases had muscle strength recov鄄ered≥M3, and 26 cases had sensory recovered≥S3; In the group of C7 transferred to the radial nerve, 6 cases had muscle strength recovered≥M3, and 9 cases had sensory recovered ≥S3; In the group of C7 transferred to the muscu鄄locutaneous nerve, 12 cases had muscle strength recovered≥M3, and 17 cases had sensory recovered≥S3.In the group of C7 simultaneous transferred to the median and musculocutaneous nerve, 6 cases had muscle strength of wrist and digital flexion recovered≥M3, 5 cases had elbow flexion recovered≥M3, 9 and 10 cases had sensory of innervated area and lateral forearm region recovered≥S3, respectively. Conclusion Contralateral C7 transfer is an ideal procedure for the treatment of total brachial plexus root avulsion with definitive clinical outcomes.
ABSTRACT
Objective To study the clinical efficacy of two-stage bone transport combined with induced membrane technique in the treatment of post-traumatic tibial osteomyelitis.Methods A retrospective study was conducted of the 14 patients with post-traumatic tibial osteomyelitis who had been treated by two-stage bone transport combined with induced membrane technique from February 2009 to August 2015.They were 12 males and 2 females,aged from 26 to 59 years (average,40.4 years).By the Cierny & Mader classification,they all belonged to type Ⅳ.Their disease course ranged from 6 to 30 months,averaging 15.3 months.The number of their previous operations ranged from 2 to 6 times,averaging 3.3 times.In the first stage of operation,tibial extended external fixation was installed according to preoperative design,followed by early debridement and extensive removal of osteomyelitis lesion.The length of bone defect after resection of osteomyelitis lesion was from 4 to 18 cm (average,8.5 cm).10％ vancomycin-contained polymethyl methacrylate (PMMA) bone cement was molded and placed in the bone defects.In the second stage of operation,the PMMA-induced membrane was opened to remove the PMMA bone cement,the bone marrow was drilled through and the induced membrane was then sutured up.Tibial osteotomy was conducted at an appropriate part.The average interval between the first and second stages was from 4 to 7 weeks (average,4.8 weeks).The clinical efficacy was evaluated according to the Paley criteria at final follow-ups.Complications were recorded.Results All the patients were followed up for 15 to 50 months (17.5 months).No relapse of osteomyelitis occurred.The total treatment time ranged from 11 to 19 months,with an average of 14.7 months.The total time for external fixation was from 10 to 18 months,averaging 13.2 months.The external fixator indexes ranged from 31 to 75 day/cm,with an average of 48.5 day/cm.According to Paley criteria at final follow-ups,the clinical efficacy was excellent in 11 and good in 3 cases.Pin tract infection occurred in 9 patients,mal-alignment after removal of external fixation in 6,and malunion or nonunion at the docking site in 5.Conclusions Two-stage bone transport combined with induced membrane technique can cure thoroughly post-traumatic tibial osteomyelitis.Its operation procedures are simple but effective.