Background Reports of applying cervical pedicle screw （CPS） system in the posterior cervical spine surgeries are limited because of its inherent risk of neurovascular injury. The clinical results of cervical spine i...Background Reports of applying cervical pedicle screw （CPS） system in the posterior cervical spine surgeries are limited because of its inherent risk of neurovascular injury. The clinical results of cervical spine instability treated with CPS system were retrospectively analyzed, and the clinical efficacy and safety of this management were evaluated. Methods Twenty-five patients with cervical spine instability undergoing posterior C3-C7 single/double door laminoplasty and free-hand CPS fixation as well as graft fusion were investigated; of whom, 3 were due to trauma, and 22 degenerative cervical pathogenesis. One hundred and fifty in total, CPSs were implanted in 5 cervical segments for 1 patient, 4 for 2, 3 for 18, and 2 for 4. Japanese Orthopaedic Association （JOA） score and its improvement rate, neck disability index （NDI）, segmental stability, pedicle cortex perforation rate and other complication-associated parameters were assessed. Results The average follow-up was 16.6 （6-30） months. Compared with pre-operative values, JOA score improved by 4.10±0.84 points on average （P 〈0.05） at 6 months post operation, with a mean improvement rate of 61%. While the pre-operative and 6-month post-operative NDI were 32.96_-＇_-~.13 and 16.84_＋4.40 （P 〈0.05）, respectively. At 6-month post-operation and the final follow-up, fused segments were stable. Pedicle cortex perforation rate was 8.0%, with no neurovascular complications observed. Conclusions Anatomizing the pre-operative radiographic data facilitates the precise operative design prior to surgery; and CPS system is capable of offering safe and satisfying outcomes in the management of cervical spine instability.展开更多
Background Recent studies showed that bone marrow-derived mesenchymal stem ceils （BMSCs） had risk of ectopic bone formation. In this study, we aimed to investigate the effect of growth and differentiation factor 6 ...Background Recent studies showed that bone marrow-derived mesenchymal stem ceils （BMSCs） had risk of ectopic bone formation. In this study, we aimed to investigate the effect of growth and differentiation factor 6 （GDF-6） on the tenogenic differentiation of BMSCs in vitro, and then combined with small intestine submucous （SIS） to promote tendon regeneration in vivo. Methods The BMSCs were isolated from the green fluorescent protein （GFP） rats, and were characterized by multi-differentiation assays following our previous study protocol. BMSCs cultured with different concentrations of GDF-6, without growth factors served as control. After 2 weeks, mRNA expression and protein expression of tendon specific markers were examined by qRT-PCR and Western blotting to define an optimal concentration of GDF-6. Mann-Whitney U-test was used to compare the difference in relative mRNA expression among all groups; P 〈0.05 was regarded as statistically significant. The GDF-6 treated BMSCs combined with SIS were implanted in nude mice and SD rat acute patellar tendon injury model, the BMSCs combined with SIS served as control. After 12 and 4 weeks in nude mice and tendon injury model, the samples were collected for histology. Results After the BMSCs were treated with different concentration of GDF-6 for 2 weeks, the fold changes of the specific markers （Tenomodulin and Scleraxis） mRNA expression were significantly higher in GDF-6 （20 ng/ml） group （P 〈_0.05）, which was also confirmed by Western blotting result. The BMSCs became parallel in orientation after GDF-6 （20 ng/ml） treatment, but the BMSCs in control group were randomly oriented. The GDF-6 （20 ng/ml） treated BMSCs were combined with SIS, and were implanted in nude mice for 12 weeks, the histology showed neo-tendon formation. In the SD rat patellar tendon window injury model, the histology also indicated the GDF-6 （20 ng/ml） treated BMSCs combined with SIS could promote tendon regeneration. Conclusions GDF-6 has tenogenic effect on the tenogenic differentiation of BMSCs, and GDF-6 （20 ng/ml） has better tenogenic effect compared to other concentrations. The GDF-6 （20 ng/ml） treated BMSCs combined with SIS can form neo-tendons and promote tendon regeneration.展开更多
文摘Background Reports of applying cervical pedicle screw （CPS） system in the posterior cervical spine surgeries are limited because of its inherent risk of neurovascular injury. The clinical results of cervical spine instability treated with CPS system were retrospectively analyzed, and the clinical efficacy and safety of this management were evaluated. Methods Twenty-five patients with cervical spine instability undergoing posterior C3-C7 single/double door laminoplasty and free-hand CPS fixation as well as graft fusion were investigated; of whom, 3 were due to trauma, and 22 degenerative cervical pathogenesis. One hundred and fifty in total, CPSs were implanted in 5 cervical segments for 1 patient, 4 for 2, 3 for 18, and 2 for 4. Japanese Orthopaedic Association （JOA） score and its improvement rate, neck disability index （NDI）, segmental stability, pedicle cortex perforation rate and other complication-associated parameters were assessed. Results The average follow-up was 16.6 （6-30） months. Compared with pre-operative values, JOA score improved by 4.10±0.84 points on average （P 〈0.05） at 6 months post operation, with a mean improvement rate of 61%. While the pre-operative and 6-month post-operative NDI were 32.96_-＇_-~.13 and 16.84_＋4.40 （P 〈0.05）, respectively. At 6-month post-operation and the final follow-up, fused segments were stable. Pedicle cortex perforation rate was 8.0%, with no neurovascular complications observed. Conclusions Anatomizing the pre-operative radiographic data facilitates the precise operative design prior to surgery; and CPS system is capable of offering safe and satisfying outcomes in the management of cervical spine instability.
文摘Background Recent studies showed that bone marrow-derived mesenchymal stem ceils （BMSCs） had risk of ectopic bone formation. In this study, we aimed to investigate the effect of growth and differentiation factor 6 （GDF-6） on the tenogenic differentiation of BMSCs in vitro, and then combined with small intestine submucous （SIS） to promote tendon regeneration in vivo. Methods The BMSCs were isolated from the green fluorescent protein （GFP） rats, and were characterized by multi-differentiation assays following our previous study protocol. BMSCs cultured with different concentrations of GDF-6, without growth factors served as control. After 2 weeks, mRNA expression and protein expression of tendon specific markers were examined by qRT-PCR and Western blotting to define an optimal concentration of GDF-6. Mann-Whitney U-test was used to compare the difference in relative mRNA expression among all groups; P 〈0.05 was regarded as statistically significant. The GDF-6 treated BMSCs combined with SIS were implanted in nude mice and SD rat acute patellar tendon injury model, the BMSCs combined with SIS served as control. After 12 and 4 weeks in nude mice and tendon injury model, the samples were collected for histology. Results After the BMSCs were treated with different concentration of GDF-6 for 2 weeks, the fold changes of the specific markers （Tenomodulin and Scleraxis） mRNA expression were significantly higher in GDF-6 （20 ng/ml） group （P 〈_0.05）, which was also confirmed by Western blotting result. The BMSCs became parallel in orientation after GDF-6 （20 ng/ml） treatment, but the BMSCs in control group were randomly oriented. The GDF-6 （20 ng/ml） treated BMSCs were combined with SIS, and were implanted in nude mice for 12 weeks, the histology showed neo-tendon formation. In the SD rat patellar tendon window injury model, the histology also indicated the GDF-6 （20 ng/ml） treated BMSCs combined with SIS could promote tendon regeneration. Conclusions GDF-6 has tenogenic effect on the tenogenic differentiation of BMSCs, and GDF-6 （20 ng/ml） has better tenogenic effect compared to other concentrations. The GDF-6 （20 ng/ml） treated BMSCs combined with SIS can form neo-tendons and promote tendon regeneration.
