成人间充质干细胞体外成骨的初步研究

目的 建立一种分离和培养成人骨髓来源的间充质干细胞（MSCs）的方法,观察成人MSCs体外成骨潜能。方法 用Percoll分离液分离出骨髓中的单个核细胞,并在含10％胎牛血清的低糖DMEM培养液中培养。通过传代培养扩增MSCs。为促进成人MSCs体外成骨性分化,第5传代培养时加入成骨性添加剂,培养第4、12天分别用流式细胞仪分析成人MSCs表面分子的表达,并用碱性磷酸酶组化染色和Von Kossa染色。结果 成人MSCs是骨髓黏附细胞中有相应细胞表面蛋白表达和形态均的一细胞群。成骨性添加剂可作用于传代培养的成人MSCs,表现为培养皿表面有相互连接的结节状聚合体、碱酶染色阳性细胞数量增多、Von Kossa染色可见钙化的基质沉积。结论 所建立的成人MSCs的分离和培养条件可分选出骨髓黏附细胞中一组独特的细胞群,成人MSCs具有体外成骨潜能。     

Expression and Role of Interleukin-6 in Distraction Osteogenesis

Distraction osteogenesis is a special form of bone healing in which well-controlled distraction stresses and consequent tensile strains within callus tissue induce very efficient new bone formation. Proinflammatory cytokines are involved during the early phase of fracture healing and callus remodeling. Temporal expression patterns of proinflammatory cytokines were assessed in Sprague-Dawley rat tibial models of distraction osteogenesis and acute lengthening, and only interleukin-6 (IL-6) was found to be specifically induced during the distraction phase. IL-6 immunoreactivity was detected not only in hemopoietic cells and osteoblasts but also in the spindle-shaped cells of the fibrous interzone, where most of the tensile strains are concentrated. In vitro study revealed that IL-6 did not affect the proliferation of C3H10T1/2 cells, mouse bone marrow stromal cells (MSCs), or MC3T3-E1 cells; but its blocking antibody reduced the proliferation of C3H10T1/2 cells and MSCs. The mRNA expression of COL1A1 and osteopontin were not changed by IL-6 or its blocking antibody, but the alkaline phosphatase activities of MC3T3-E1 cells were increased by IL-6 and decreased by its blocking antibody. These findings indicate that IL-6 is a proinflammatory cytokine that responds to tensile strain during distraction osteogenesis. IL-6 negatively affects the proliferation of primitive mesenchymal cells, whereas the differentiation of more mature osteoblastic lineage cells is enhanced by IL-6 in vitro. IL-6 appears to be one of the cytokines involved in the complex network of signal cascades evoked during distraction osteogenesis and may differentially affect immature and mature osteoblastic lineage cells.     

Reverse Sural Flap with Bifocal Ilizarov Technique for Tibial Osteomyelitis with Bone and Soft Tissue Defects

Tibial osteomyelitis, in association with bone loss and a soft tissue defect, poses a significant reconstructive challenge, especially in high-risk patients. We describe a case of methicillin-resistant Staphylococcus aureus tibial osteomyelitis with intercalary bone loss successfully managed with bifocal Ilizarov compression osteogenesis at the bone resection site and proximal distraction osteogenesis, accompanied by a reverse sural fasciocutaneous flap performed with a delayed technique. When free tissue transfer is not a reconstructive option owing to medical comorbidities or patient refusal, the reverse sural flap combined with bifocal Ilizarov compression and distraction osteogenesis can provide a reconstructive option to achieve limb salvage for these challenging cases.     

BMP‐2 mediates PGE2‐induced reduction of proliferation and osteogenic differentiation of human tendon stem cells

Tendon stem cells (TSCs) have been proposed to play a major role in the development of tendinopathy, which refers to pathological changes, such as calcification, in affected tendons. Using a human TSC (hTSC) culture model, this study investigated the effects of PGE₂, an inflammatory mediator present in injured tendons, on hTSC proliferation and differentiation as well as the molecular mediator for such PGE₂‐induced effects. We found that PGE₂ treatment of hTSCs decreased cell proliferation and caused osteogenic differentiation of hTSCs in a dose‐dependent manner. Also, PGE₂ treatment of hTSCs induced dose‐dependent BMP‐2 production in culture, and moreover, addition of BMP‐2 to hTSC culture decreased cell proliferation and induced hTSC differentiation into osteoblasts. Finally, addition of BMP‐2 antibodies to hTSC culture treated with PGE₂ nearly abolished PGE₂ effects on both cell proliferation and osteogenic differentiation. Taken together, the findings of this study showed that BMP‐2 mediates PGE₂‐induced reduction of proliferation and osteogenic differentiation of hTSCs. We suggest that such a mechanism may be partially responsible for the formation of calcified tissues in tendinopathic tendons seen in clinical settings. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:47–52, 2012     

牙槽嵴裂隙间固定对腭裂上颌复合体内置式牵引成骨生物力学的影响

目的 探讨裂隙间固定对唇腭裂上颌复合体牵引成骨生物力学的影响.方法 采用三维有限元方法,建立唇腭裂上颌复合体LeFort Ⅰ型截骨骨块及相应软组织有限元模型,在保留牙槽嵴裂隙与裂隙两侧钛板固定两种情况下,模拟临床上内置式牵引方式,使截骨块上牵引器固位点沿牵引方向前移10 mm,比较分析其生物力学变化.结果 唇腭裂上颌复合体LeFort Ⅰ型截骨内置式牵引下,腭部出现压缩现象,而裂隙两侧钛板固定腭部压缩现象不明显.矢向位移与垂直向位移在两种工况下比较,位移方向及大小与保留裂隙的前牵引无明显差异.结论 裂隙间固定后唇腭裂上颌复合体内置式牵引成骨,可以避免腭部出现压缩现象,有生物力学指导意义.     

牵引成骨技术治疗颌面畸形

目的 探讨应用口外颌骨牵引成骨装置治疗颌面畸形。方法 使用自行设计制作的口外颌骨牵引成骨装置和上颌杠杆式牵引支架分别水平延长下颌骨，水平快速前移上颌骨，垂直延长下颌骨升支，水平延长下颌骨颏部，用以矫正小下颌畸形，下颌骨颏部外伤性骨缺损，小颌偏颌畸形，半侧前面肥大畸形，咬合平面倾余和唇腭裂术后上颌后缩等，共11例。结果 4例不同类型下颌骨牵引成骨，其中有1例在牵引过程中1根克氏针发生松动，旋转，最终将克氏针取出。1例下颌升支垂直牵引4根克氏针发生轻度弯曲，7例唇腭裂上颌后缩行Le Fort Ⅰ型截骨快速牵引成骨中有1例固定期后1个月出现对刃合并有轻度开咬合。最终11例治疗效果满意。结论 口外颌骨牵引成骨装置治疗下颌骨复杂畸形。Le Fort Ⅰ型截骨快速牵引成骨治疗唇腭裂术后上颌后缩是一种安全简便效果可靠的有效方法。     

骨缝牵引成骨修复腭裂的临床初步研究

目的 临床探索骨缝牵引成骨修复腭裂的新技术。方法 选择2～4岁的腭裂患儿。一期手术在全麻下安置腭裂牵引器，牵引腭骨向中线和向后移动；牵引期持续约4～5个月。裂隙合拢后进行二期手术，修复裂隙。用误差为0．2％的游标卡尺，测量牵引前和牵引后上颌牙弓宽度、裂隙宽度和硬腭长度。结果 临床应用8例。2例因牵引器在安置后l周内脱落而终止牵引。6例经不同时间的牵引后，裂隙缩小，裂隙两侧的组织显著延长。其中牵引时间最长为126d，最短为37d；裂隙宽度平均缩小6．5mm；硬腭长度平均延长4．8mm。结论 临床证实了骨缝牵引具有诱导腭部组织再生、关闭或缩小裂隙和延长硬腭的可能性。     

The Effects of botulinum toxin A on muscle histology during distraction osteogenesis

Distraction osteogenesis is a highly successful method of bone formation, yet muscle fibrosis and contractures can result in significant morbidity. In the current study, we investigate the efficacy of botulinum toxin A in preventing fibrosis and potentially increasing muscle development in distracted muscles. Fifteen New Zealand White rabbits underwent tibial distraction at 1.5 mm/day until a 20% gain was achieved. Treatment groups were divided by drug (saline or botulinum toxin) and target muscle (gastrocnemius or tibialis anterior). Two additional control animals received no treatment. Bromeodeoxyuridine was delivered continuously throughout the 8‐week experiment, and following muscle harvest. Tissues were stained for BrdU, Pax‐7, vimentin, and haematoxylin and eosin staining. Mitotic activity increased in all distracted animals; however, in the animals receiving botulinum toxin A injections into the gastrocnemius, the antagonist tibialis anterior suffered up to 9% less fibrosis than distraction alone (p = 0.024). Use of botulinum A toxin did not appear to promote or improve neogenesis of muscle fibers, nor did it decrease fibrosis in the injected muscles. It appears from this study, and a previously published study on the effects of this toxin on muscle function, that botulinum A toxin maybe of some benefit in decreasing morbidity in the antagonist muscle but not the muscle injected with the toxin. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:310–317, 2009     

External fixation reconstruction of the residual problems of benign bone tumours

The mechanical features of and biologic response to using distraction osteogenesis with the circular external fixator are the unique aspects of Ilizarov’s contribution that allows deformity correction and reconstruction of bone defects. We present a retrospective study of 20 patients who suffered from a variety of benign tumours for which external fixators (EF) were used to treat deformity, bone loss, and limb-length discrepancy. A total of 26 bony segments in twenty patients (10 males, 10 females; mean age 17 years; range 7–58 years) were treated with EF for residual problems from the tumour itself (primary treatment) in 8 patients and for complications related to the primary surgery (secondary treatment) in 12 patients. Histological diagnoses were Ollier’s disease (n = 4), Fibrous Dysplasia (n = 5), Congenital multiple exostosis (n = 5), giant cell tumour (n = 2) and one case for chondromyxoid fibroma, desmoid fibroma, chondroma and unicameral bone cyst. Various types of external fixators used to treat these problems. These were Ilizarov, unilateral fixator, multiaxial correction frame (Biomet, Parsippany, NJ), Taylor spatial frame (Memphis, TN) and smart correction multiaxial frame. The mean follow-up time was 69.5 months (range 35–108 months). The mean external fixation time was 159.5 days (range 27–300 days). The mean external fixation index was 67.4 days/cm (12–610) in 26 limbs who underwent distraction osteogenesis. The mean length of distraction was 4.9 cm (range 0.2–14 cm). At final follow-up, all patients had returned to normal activities. Complications were in the form of knee arthrodesis in one patient, pin tract infection in six and residual shortening in eight patients. The use of EF and the principles of distraction osteogenesis, in the management of problems associated with benign bone tumours and related surgery yields successful results especially in young patients. With this approach, the risk for recurrence of shortening and deformity may be minimized with overcorrection or over-lengthening as dictated by preoperative planning.