多孔双相钙磷陶瓷在脊柱后路融合中成骨作用和降解特性的组织学观察(附20例活检分析)

[目的]了解多孔双相钙磷陶瓷在人体脊柱后路融合中的成骨变化及降解过程。[方法]对20例脊柱后路融合的双相钙磷陶瓷活检标本行不脱钙硬组织切片检查。观察陶瓷周围和内部的新生组织、陶瓷的形态改变、降解颗粒及伴随的细胞吞噬反应。其中14例标本行组织形态计量，根据患者的年龄、植入时间及临床结果分组比较成骨及材料降解的速度。[结果]所有的双相钙磷陶瓷标本均可见新生骨组织，与自体骨接触越多，陶瓷内的新生骨组织越多。绝大部分陶瓷内可见降解颗粒，部分颗粒位于巨噬细胞内。不同标本的新生骨和材料降解速度差异较大。陶瓷内的新生骨随植入时间的增加而增多，但随患者年龄的增大而减少。陶瓷的降解率随患者年龄的增大而减少，但不受植入时间的影响。后路融合成功组的活检标本的新生骨量高于融合失败组，但材料降解率则反之。[结论]多孔双相钙磷陶瓷是一种骨传导材料，但植入体内降解缓慢，不能被新生骨组织完全替代。植入时必须将陶瓷与自体骨充分混合以获得良好的骨长入。陶瓷产生的降解颗粒及诱发的细胞吞噬反应必须引起注意。     

双相生物钙磷陶瓷生物相容性及异位骨诱导的实验研究

目的检测运用羟基磷灰石及β-磷酸三钙制备的双相钙磷陶瓷的生物相容性及其异位骨诱导效率。方法采用化学共沉淀法及过氧化氢发泡法,将羟基磷灰石及β-磷酸三钙以6∶4的比例在1 100 ℃条件下烧结3 h获得双相钙磷陶瓷,利用X线衍射评估材料组成成分。分离SD大鼠骨髓间充质干细胞,接种于双相钙磷陶瓷,通过扫描电镜、鬼笔环肽及DAPI染色观察细胞的黏附,CCK8法评估细胞增殖,碱性磷酸酶测定法评估骨髓间充质干细胞的碱性磷酸酶表达活性。将不含骨髓间充质干细胞的双相钙磷陶瓷置入比格犬竖脊肌内,于4、8、12周对样本行大体检测、组织染色,测算新骨生成率,从而评估双相钙磷陶瓷的异位骨诱导效率。结果成功制备双相钙磷陶瓷,X线衍射分析可见羟基磷灰石及β-磷酸三钙特异性的衍射峰。扫描电镜可见双相钙磷陶瓷表面广泛分布大孔及连通孔,孔壁粗糙不平,孔内可见均匀分布的微孔。鬼笔环肽及DAPI染色显示,骨髓充质干细胞在材料表面伸展黏附,共培养后逐渐从不规则形转变为均一的长梭形。CCK8法提示共培养后第1天,细胞活力降低,而第3、4、5、7天,细胞增殖活力逐渐增加。碱性磷酸酶活性检测提示,与对照组相比,共培养后第1、7天,双相钙磷陶瓷组的骨髓间充质干细胞可分泌更多的碱性磷酸酶。双相钙磷陶瓷顺利置入比格犬竖脊肌内,术后8周材料孔隙内可见骨样组织沉积,术后12周大孔成骨比例为0.77±0.11,孔内成骨面积比例为0.71±0.14。结论双相钙磷陶瓷具有良好的生物相容性及异位骨诱导效率。     

Use of biphasic calcium phosphate versus demineralized bone matrix: retrospective clinical and CT analysis of posterolateral fusion results

Purpose

Bone graft extenders have been developed to prevent donor site morbidity associated with iliac crest bone graft, but few studies compared the efficacy of various substitutes. Our purpose was to determine fusion rate and clinical outcome in patients undergoing lumbar arthrodesis using demineralized bone matrix (DBM) and biphasic calcium phosphate (BCP).

Methods

Patients with degenerative spondylolisthesis undergoing one-level or two-level arthrodesis of lumbar spine were retrospectively reviewed. Two treatment groups placed either BCP or DBM, in addition to local autograft in lumbar posterolateral space. Three-dimensional CT exam and dynamic flexion–extension radiographs at postoperative 2-year were assessed for posterolateral fusion status and pain scale and Oswestry Disability Index (ODI) for clinical outcome.

Results

Of the 148 patients reviewed (including 23 in one- and 58 patients in two-level in BCP group, and 47 in one- and 20 patients in two-level in DBM group), no significant differences were found in terms of age, sex, BMI, smoking, diabetes, steroids, number of level fused, non-union rate or revision surgery between BCP and DBM groups. Significantly improved pain scale of back and leg and ODI were found in both groups postoperatively without group difference. We found a comparable fusion rate in one-level surgery (100% versus 93.6%) and a superior fusion rate of BCP group in two-level surgery (98.3% versus 80.0%, p = 0.01).

Conclusion

Being a bone graft extender without osteoinductive property, with local autograft, BCP is comparable to DBM for one- and superior for two-level fusion. No significant difference was found in clinical outcomes.

     

Experimental posterolateral spinal fusion with beta tricalcium phosphate ceramic and bone marrow aspirate composite graft

Background:

Beta tricalcium phosphate is commonly used in metaphyseal defects but its use in posterolateral spinal fusion remains controversial. There are very few published animal studies in which use of beta tricalcium phosphate has been evaluated in the posterolateral lumbar arthrodesis model. Hence we conducted a study to evaluate the potential of composite graft of beta tricalcium phosphate and bone marrow aspirate in comparison to autologous bone graft, when used for posterolateral spinal fusion.

Materials and Methods:

Single level posterolateral lumbar fusion was performed in 40 adult male Indian rabbits, which were assigned randomly into one of the four groups based on graft materials implanted; a) 3 gm beta tricalcium phosphate plus 3 ml bone marrow aspirate (Group I); b) 3 ml bone marrow aspirate alone (Group II); c) 3 gm beta tricalcium phosphate (Group III) and d) 3 gm autologous bone graft (Group IV). Each group had 10 rabbits. Half of the rabbits were sacrificed by injecting Phenobarbitone intraperitoneally after eight weeks and the remaining after 24 weeks, and were evaluated for fusion by X-rays, computed tomography (CT) scans, manual palpation test and histology.

Results:

Beta tricalcium phosphate used with bone marrow aspirate produced best results when compared to other groups (P =.0001). When beta tricalcium phosphate was used alone, fusion rates were better as compared to fusion achieved with autologous iliac crest bone graft though statistically not significant (P =0.07). Autologous bone graft showed signs of new bone formation. However, the rate of new bone formation was comparatively slow.

Conclusion:

Composite graft of beta tricalcium phosphate and bone marrow aspirate can be used as an alternative to autologous iliac crest bone graft.     

Macroporous calcium phosphate ceramic performance in human spine fusion

With a background of experimental studies on macroporous biphasic calcium phosphate (MBCP) in canine spine fusion, MBCP was investigated in 11- to 18-year-old patients with scoliosis treated by spinal fusion. Twelve cases were chosen for whom enough bone graft was difficult to obtain (severe neurologic scoliosis and osteogenesis imperfecta). MBCP blocks were used in combination with a specific strong fixation (Cotrel-Dubousset instrumentation). Clinical and roentgenogram assessments were performed up to 24 months. In two cases, biopsies were obtained. Histologic, ultrastructural, and microanalysis studies demonstrated the effectiveness of MBCP implants combined with a strong stabilization as bone graft substitutes for spine fusion. Clinical and biologic assessments were normal, and the histologic and ultrastructural evaluation demonstrated the bioactivity and the osteoconduction of this material. Partial resorbability of the MBCP blocks involved lamellar bone formation at the expense of the ceramic.     

组织工程复合骨移植材料椎体间脊柱融合实验研究

目的:观察组织工程复合骨移植材料在兔腰椎椎体间脊柱融合的愈合情况。方法:自体骨髓基质细胞体外培养,诱导分化为成骨细胞,种植到多孔钙磷陶瓷载体中,体外旋转细胞培养构建成组织工程复合骨移植材料。实验分为5组:假手术组、空载体组、自体髂骨组、旋转培养复合体组和rhBMP-2复合体组。椎体间移植12周后,通过大体观察、手法检测、影像学、生物力学和组织学方法评价脊柱融合愈合情况。结果:假手术组不能自行达到脊柱融合;空载体移植组脊柱融合率为50%;自体髂骨移植组为66.7%;旋转培养复合体组和rhBMP-2复合体移植组为100%,融合块较大,生物力学强度高。结论:旋转细胞培养方法构建的骨髓基质来源的成骨细胞-钙磷陶瓷复合骨移植材料椎体间脊柱融合率优于自体髂骨移植,可以替代自体髂骨进行椎体间脊柱融合;复合骨移植材料中结合骨生长因子rhBMP-2能够进一步加强脊柱融合的生物力学强度。     

Efficacy of silicated calcium phosphate graft in posterolateral lumbar fusion in sheep.

BACKGROUND CONTEXT: Conditions requiring posterior lumbar spinal fusion remain a clinical challenge. Achieving arthrodesis using autogenous bone graft is inconsistent when rigid internal fixation such as transpedicular instrumentation is applied. Synthetic materials, particularly calcium phosphate-based ceramics, have shown promise for spine fusion applications, especially when combined with autograft. Silicate substitution has been shown to enhance the bioactivity of calcium phosphates and may obviate the need for autologous supplementation. PURPOSE: Determine efficacy of silicated calcium phosphate (Si-CaP) compared with autograft to generate solid lumbar fusion. STUDY DESIGN: Comparison of healing of instrumented posterolateral lumbar fusion in ewes at 2 and 6 months using Si-CaP or iliac crest autograft. METHODS: Eighteen skeletally mature ewes underwent implantation of either autograft or Si-CaP in the space spanning the L4-L5 transverse process. In vivo quantitative computed tomography (CT) scans were made at 2-month intervals and after euthanasia. Harvested spine segments were radiographed and biomechanically tested in bending at 6 months. Histological assessments were made at 2 and 6 months. RESULTS: Animals receiving Si-CaP graft were biomechanically and radiographically equivalent to those receiving autograft. Fusion mass density and volume were higher for the Si-CaP group throughout the healing period. Si-CaP regenerated normal bone tissue morphology, cellularity, and maturation with no inflammatory responses despite the fact that no autograft, bone marrow aspirate, or blood was mixed with the material. Histomorphometrically, fusion mass was higher for Si-CaP and bony bridging was equivalent when compared with autograft treatment. CONCLUSIONS: Si-CaP was biomechanically, radiographically, and histologically equivalent to autograft in generating a solid, bony, intertransverse process fusion in an ovine model. Both treatment groups achieved 100% bridging fusion after 6 months of healing.     

Silicate-substituted calcium phosphate ceramic bone graft replacement for spinal fusion procedures

STUDY DESIGN.: Retrospective study. OBJECTIVE.: To assess the clinical and radiographical outcomes in spinal fusion procedures using silicate-substituted calcium phosphate (Si-CaP). SUMMARY OF BACKGROUND DATA.: Si-CaP is a newer-generation synthetic ceramic designed to maximize osteoinduction and osteoconduction. METHODS.: This is a retrospective analysis of a prospectively collected patient database including 108 patients (204 individual spinal levels). Different surgical procedures performed included 25 anterior cervical discectomy and fusions, 17 posterior cervical fusions, 7 combined anterior and posterior cervical fusions, 10 thoracic fusion surgeries, 18 transforaminal lumbar interbody fusions with 12 axial lumbar interbody fusions, 11 transpsoas discectomy and fusions, and 8 combined thoracolumbar fusion procedures. Si-CaP was used as bone extender without any additional graft material, bone marrow aspirate, or bone morphogenetic protein. Clinical outcomes were assessed using the visual analogue scale (VAS), Oswestry Disability Index, and Neck Disability Index. Fusion was determined by the presence of bony bridging on 2 consecutive sections in at least 2 planes on computed tomographic imaging. RESULTS.: At a follow-up of 12 (±4.7) months, 90% of all patients demonstrated radiographical fusion. Fusion rates were highest in the cervical spine (97%) followed by thoracic and lumbar spines (86% and 81%, respectively). There were significant improvements in all clinical outcome measures-Oswestry Disability Index, 11.1 (±10.2) and Neck Disability Index, 9.0 (±11.4); VAS-back, 3.1(±3.0); VAS-leg, 3.5 (±3.6); VAS-neck, 3.7 (±2.5); and VAS-arm 4.0 (±3.2). There was no radiographical loosening of instrumentation due to infection or nonunion in this series, and no subsequent revisions for nonunion were required. CONCLUSION.: Si-CaP is an alternative to autogenous bone graft in spinal arthrodesis procedures. At 12-month follow-up, we detected high levels of bony fusion using Si-CaP in combination with various surgical spinal techniques.     

新型多孔双相磷酸钙支架与兔骨髓间充质干细胞相容性的体外实验研究

目的：研究新型多孔双相磷酸钙支架与兔骨髓间充质干细胞的体外相容性。方法：体外分离、扩增兔骨髓间充质干细胞。取传二代细胞,按照经典组织工程构建方法,分别接种双相磷酸钙（对照组）和双相磷酸钙复合纳米羟基磷灰石（实验组）支架。单纯细胞培养为空白对照组。体外成骨诱导培养14天。倒置相差显微镜、扫描电镜观察细胞生长情况;MTT法检测细胞增殖功能;碱性磷酸酶（ALP）检测细胞成骨分化功能。结果：细胞在新型支架上吸附、生长良好。各组MTT及ALP值随培养时间延长而增大。培养各时段实验组均高于其他两组,差别有统计学意义（P〈0.01）。结论：新型BCP支架与兔BMSC在体外具有良好的相容性,二者具有体外构建工程骨的潜力。     

The evaluation of a biphasic calcium phosphate ceramic for use in grafting long-bone diaphyseal defects

The effectiveness of a sintered hydroxyapatite-tricalcium phosphate (HA-TCP) ceramic in bridging large diaphyseal defects in the canine ulna was studied. One-hundred percent morselized HA-TCP, a 50:50 mixture of morselized HA-TCP, and autogenous cancellous bone, and 100% autogenous cancellous bone were used to bridge 2.5-cm defects in the left ulnae of three groups of six dogs each. At 24 weeks the ulnae were explanted and studied by radiography, microradiography, mechanical testing, and histology. Pure HA/TCP was not osteoinductive, and four of six ulnae in this group progressed to a fibrous nonunion. The HA/TCP-cancellous bone mixture and pure cancellous bone were approximately equal in effect, leading to good callus formation at 4 weeks and strong bony union by 24 weeks, with no evidence of bioincompatibility. Morselized HA/TCP promises to be useful as a graft extender when mixed with autogenous cancellous bone.     

Cage containing a biphasic calcium phosphate ceramic (Triosite) for the treatment of cervical spondylosis

BACKGROUND: We evaluated the fusion efficacy and clinical outcomes of a cage containing a biphasic calcium phosphate ceramic (Triosite) in treating cervical spondylosis. METHODS: We randomly divided 100 patients with cervical spondylosis undergoing anterior discectomy with interbody polyetheretherketone (PEEK) fusion into 2 groups in the past 2 years: group A (n = 50), PEEK cage containing a biphasic calcium phosphate ceramic (Triosite), and group B (n = 50), PEEK cage containing an autogenous iliac bone graft. We compared the fusion rate, fusion time, spinal curvature, and neuroforamen size between the 2 groups. We also compared excess operation time, excess blood loss, hospital stay, complications, and neurological recovery status between the groups. RESULTS: The fusion rates were 57%, 67%, 77%, 82%, 92%, and 100% in group A and 81%, 86%, 95%, 95% 100%, and 100% in group B in the first 6 postoperative months. The fusion rate in group A was significantly lower than that in group B in the first 5 months after the procedure (P < .05 and P < .01, respectively), but the fusion rate reached 100% in both groups by the sixth month. Within the first 6 months, as the fusion level increased, the fusion rates reduced and time to fusion was delayed in both groups. There were no donor site complications in group A. However, 3 patients (6%) from group B experienced complications (1, wound infection; 1, numbness of thigh; and 1, subcutaneous hematoma) (P < .001). The hospital stay was shorter in group A (4.43 +/- 2.36 days) than in group B (7.00 +/- 3.77 days) (P = .001). The mean excessive blood loss and excessive operative time for an iliac bone graft in group B were 15 +/- 5 mL and 10 +/- 6 minutes. There was no statistical significance in spinal curve correction, neuroforamen enlargement, and neurological recovery. CONCLUSIONS: A cage containing a biphasic calcium phosphate ceramic resulted in complete fusion by the sixth postoperative month, although the fusion rate was lower than that in a cage containing an autograft during the first 5 months after the operation and the time to fusion was delayed. Using a cage containing a biphasic calcium phosphate ceramic leads to a shorter hospital stay, less blood loss, shorter operative time, and no donor site complications. It seemed to be a good substitute for cervical spondylotic fusion.     

Experimental data regarding macroporous biphasic calcium phosphate ceramics

Summary Macroporous biphasic calcium phosphate ceramics are biocompatible. Their physico-chemical structure is close to the mineral phase of the bone and provides bioactivity. Shortly after implantation in osseous area, dissolution appears with precipitation and formation of apatite crystals. Soon after osteoclastic resorption begins osteoconduction inside the macropores. Mechanical studies reveal a significant improvement in the mechanical properties due to the growth of the trabecular bone. Animal experiments in the spine have demonstrated bone penetration which allows a postero-lateral fusion. The rigidity of the fusion is equivalent to that obtained with bone graft. Macroporous biphasic calcium phosphate can be applied to fill bone defects and for postero-lateral spine fusion.     

自体骨髓基质干细胞与钙磷陶瓷复合体在恒河猴腰椎前路融合中的实验研究

目的 评价自体骨髓基质干细胞（BMSCs）与钙磷生物陶瓷复合体的成骨效果。方法2003年3月至2005年4月,对9只成熟恒河猴行经腹膜外L3-4和L5-6腰椎间盘切除脊柱融合术。每只动物的两个脊柱节段随机接受3种治疗方法中的2种：自体髂骨移植（自体骨组,n=6）,空载体陶瓷移植物（陶瓷组,n=6）和骨髓基质干细胞-陶瓷复合体（BMSCs组,n=6）。自髂骨抽取骨髓,在含有成骨细胞诱导因子的培养液中体外扩增自体BMSCs,利用旋转培养方法构建骨髓基质干细胞-钙磷陶瓷复合体供移植用。实验动物在术后3个月处死,利用放射学、生物力学测试、组织学和组织形态计量学观察和分析脊柱融合节段。结果生物力学测试结果和组织学结果显示BMSCs组的椎体间脊柱融合效果明显好于陶瓷组;BMSCs组和自体骨组显示出近似的生物力学强度。BMSCs组和自体骨组的骨量显著多于陶瓷组;但陶瓷组的陶瓷材料残余量显著多于BMSCs组。结论在恒河猴椎体间脊柱融合模型中,自体骨髓基质干细胞和钙磷生物陶瓷复合体在移植入体内3个月内有良好的成骨并获得椎体间骨性融合。     

Autogeneic bone marrow and porous biphasic calcium phosphate ceramic for segmental bone defects in the canine ulna.

The purpose of this study was to evaluate a porous biphasic hydroxyapatite-calcium phosphate ceramic as a modifier and extender of an autogeneic marrow graft for filling a 2.5-cm segmental bony defect. Twenty adult mongrel dogs were surgically treated to create diaphyseal defects in the left ulnae. The defects were (1) filled with autogeneic bone marrow mixed with granular hydroxyapatite-tricalcium phosphate ceramic (granular ceramic); (2) grafted with a solid block of ceramic soaked in autogeneic bone marrow (block ceramic); (3) received no graft (no implant); or (4) were grafted with autogeneic bone marrow alone (bone marrow). All animals were followed clinically and roentgenographically for 24 weeks and then killed. Repair of diaphyseal defects with the block ceramic led to three solid unions and three fibrous unions; with the granular ceramic implants and marrow, the defects of five dogs formed solid unions, and one progressed to a fibrous union. Defects in all five dogs grafted with autogeneic bone marrow united. The three dogs with no implant formed nonunions. Histology showed normal marrow and only a light immune reaction. Complete bridging of the defect in the dogs treated with the granular ceramic occurred significantly earlier than bridging in the dogs grafted with bone marrow alone. Histomorphometry, performed on the block ceramic implants indicated active resorption of ceramic. Clinically, addition of ceramic to a marrow graft improved the handling characteristics of the graft material and accelerated healing according to roentgenographic evaluation.     

Macroporous calcium phosphate ceramic: a prospective study of 106 cases in lumbar spinal fusion

Macroporous biphasic calcium phosphate (MBCP, Triosite) is well known for its safety, absence of allergenicity, and excellent bone-bonding capacity, and it has been widely used as a bone graft substitute in orthopaedic, ENT, and dental surgery. This study investigates the clinical performance of this synthetic porous ceramic in a series of 106 patients, mainly with degenerative spine aetiologies (95/106) and with a minimum follow-up of 2 years. All patients were treated with posterior correction involving the semi-rigid New Orleans instrumentation. Spinal fusion was always performed using MBCP granules mixed with autogenous bone chips and bone marrow obtained from the local spine. Fusion of the spine was confirmed for 100 patients, and 6 non-unions were observed (3 resulting from primary spondylolisthesis). This study shows that MBCP provides suitable results in spinal fusion involving a semi-rigid instrumentation. Because the indication of degenerative spine is not very favorable to fusion, this technique appears to be a good alternative to autografts and could decrease patient morbidity resulting from iliac bone grafting.     

Lumbar posterolateral fusion alone or with transpedicular instrumentation in L4--L5 degenerative spondylolisthesis

We retrospectively reviewed 57 patients with L4--L5 degenerative spondylolisthesis (L4--L5 DS) who underwent posterior decompression and posterolateral fusion of L4--L5 without (Group A) or with (Group B) transpedicular screw instrumentation at least 2 years earlier. The clinical results and fusion rate were similar between Groups A and B, that is, a 72.4% satisfactory outcome with a fusion rate of 82.8% in Group A versus 82.1% satisfactory outcome with a 92.8% fusion rate in Group B. Screw instrumentation reduced postoperative low back pain and resulted in a lordotic slip angle of L4--L5. However, in patients with radiologically excessive segmental motion showing a translational motion of 3 mm or more, flexion angulation of -5 degrees or less, and a slip angle of -5 degrees or less at the site of spondylolisthesis (L4--L5), the kyphotic slip angle (L4--L5) tended to increase after surgery. In the future, in patients with radiologically excessive segmental motion, this point should be considered, and surgical techniques should be evaluated. Our results suggest that the validity of the general addition of screw instrumentation to L4--L5 fusion for L4--L5 degenerative spondylolisthesis is low.     

Collagen and biphasic calcium phosphate bone graft in large osseous defects

The cavity left by the removal of tumors represents a challenge for the orthopedic oncologic surgeon. This article takes a critical look at the use of a synthetic bone graft to fill the residual space. A combination of hydroxyapatite, tricalcium phosphate, and bovine collagen was used for intramedullary tumors. Thirty patients were followed for an average of 23 months. The majority (93%) returned to full activity with only 6 (20%) complications. Study results showed collagen and biphasic calcium phosphate ceramic bone graft makes an effective substrate for filling intramedullary cavities remaining after tumor excision.     

纳米磷酸钙陶瓷人工骨的临床应用研究

目的：探讨纳米磷酸钙陶瓷人工骨移植治疗骨缺损的安全性和临床效果。方法：2005年3月至2007年11月应用纳米陶瓷人工骨治疗四肢骨缺损病例32例（人工骨组）,男19例,女13例;年龄17～63岁,平均31.4岁。同期骨折内固定患者36例（内固定组）,男21例,女15例;年龄16～65岁,平均32.6岁。两组患者于术后第1、2周及第1、3、6个月检测外周静脉血中Ca、P、BALP、IgG、IgA、IgM、CIC、C3、SL2R及CD4＋/CD8＋的比值。并随访用Enneking标准评价肢体功能。结果：两组患者伤口术后均顺利愈合,各项免疫学检查无明显差异（P〉0.05）,均未引起血清中钙和磷的明显增高,术后两组B-ALP均升高,3～6个月后内固定组恢复至正常水平,人工骨组仍维持较高水平。随访9～24个月,平均15个月,两组患者均获得了较好的肢体功能,Enneking评价无明显差异（P〉0.05）。结论：所用纳米陶瓷人工骨无免疫原性,未引起排斥反应,不影响血液中钙、磷水平,并有一定的成骨活性,临床用以修复腔隙性骨缺损效果肯定。