不同植骨材料重建伤椎修复胸腰椎爆裂骨折:验证植骨愈合

背景:椎体内植骨重建椎体前中柱结构及恢复椎体形态被重新认识,选择合适的植骨材料可以促进骨愈合,有利于重新建立长期脊柱的稳定性。目的:探讨3种不同植骨材料经单侧椎弓根植入重建椎体治疗胸腰椎爆裂骨折的疗效差异。方法:纳入胸腰椎爆裂骨折患者102例,按随机数字表法分3组治疗,分别采用后路经单侧椎弓根植入自体骨、自体骨联合同种异体骨与同种异体骨。植骨前后采用X射线观察椎体前缘高度百分比及Cobb角,CT观察伤椎椎体内植骨愈合,选择终末随访CT用Mimics软件计算伤椎骨缺损面积。结果与结论:102例患者均获得24-36个月随访。3组植骨后不同时间点椎体前缘高度百分比、Cobb角均较植骨前恢复(P0.05);植骨后不同时间点3组间椎体前缘高度百分比比较差异无显著性意义;同种异体骨组植骨后9,12,24个月的Cobb角高于自体骨组、自体骨联合同种异体骨组(P0.05)。同种异体骨组植骨不同时间点骨愈合率低于自体骨组、自体骨联合同种异体骨组(P0.05),骨缺损面积高于自体骨组、自体骨联合同种异体骨组(P0.05)。表明3种植骨材料经单侧椎弓根重建椎体形态治疗胸腰椎爆裂骨折,能够减少椎体高度、Cobb角丢失和骨缺损面积,自体骨联合同种异体骨在骨愈合及减少骨缺损方面与自体骨疗效相似,均优于同种异体骨。     

硫酸钙人工骨在良性骨肿瘤刮除术后骨缺损填充中的愈合情况及其重建作用研究

目的观察硫酸钙人工骨在良性骨肿瘤刮除术后骨缺损填充中的愈合情况,探讨其在骨肿瘤患者中的重建作用。方法回顾性分析在2010年1月~2013年9月期间,我院骨外科收治的临床随访资料完整的良性骨肿瘤患者,根据植骨材料的不同,分别采用硫酸钙人工骨、同种异体骨以及自体骨修复肿瘤刮除术后骨缺损。每组各选择随机样本40例。根据术后随访的X线结果和相关临床资料。评估不同移植骨在良性骨肿瘤缺损填充中的降解、吸收和愈合情况。结果 120例患者获得3~48个月随访,平均随访时间14.7个月。随访期自体骨组、硫酸钙人工骨组和同种异体骨组均未发生深部感染、植骨不愈合、伤口不愈合、植骨部位骨折及肿瘤复发等相应的并发症,临床获益率达100%。三组病例在骨愈合时间无统计学意义,愈合率也无显著性差异(0.05)。结论用硫酸钙人工骨材料填充良性骨肿瘤刮除后的骨缺损,愈合效果与自体骨和同种异体骨相近。且硫酸钙人工骨生物相容性好,并发症少,值得在临床上推广。     

同种异体骨移植治疗骨缺损的应用研究进展

由创伤、骨感染、骨肿瘤切除后造成的大段骨缺损的修复一直是临床治疗的难点之一。在传统治疗方法中,利用自体骨游离移植修复骨缺损,虽然有无免疫排斥反应、易愈合等优点,但是存在骨组织来源有限、二次创伤等缺点。虽然人工替代物置换、骨延长转移术等已在临床上得以应用,但均存在各自的不足。针对它们的不足之处,近年来带血管骨膜同种异体骨游离移植的应用使骨缺损的治疗有了迅速的发展。虽然同种异体骨移植存在细菌和病毒感染、骨折、不愈合、延迟愈合等风险,但由于它的结构类似于自体骨,排斥反应较异种骨小,而且不存在自体骨移植骨组织来源有限、二次创伤等问题,使其成为修复骨缺损的常用材料。现就同种异体骨治疗骨缺损的应用研究进展综述如下。     

同种异体骨移植：一个引人关注的问题

同种异体骨移植现在被广泛用于修复骨的材料,特别是用于骨肿瘤切除后关节功能的重建和保肢手术,但是现在英国部分医院异体骨移植做得还不够。尽管这是一种普遍的疗法,但关于它的生物学、处理和安全性方面一些问题仍然没有解决。与移植有关失败的报告诸如感染,骨折和骨不连的并发症是比较常见的。 在同种异体移植中深部感染通常是灾难性的,它的发生是随着移植物大小增加而增加,在大块同种异体骨移植中有10％以上病例发生感染,它的发生似乎与手术前移植物的污染无关,可能与手术过程的复杂性和死骨片样骨与自体骨愈合不良有关。这种愈合过程也好像削弱了骨的强度,易于产生骨折。在大块异体骨移植的大宗病例中,Mankin和他的同伴们报告     

骨关节肿瘤型假体的研究与应用现状

<正>1骨肿瘤的治疗现状从20世纪70年代开始的骨肉瘤综合治疗已成为骨肉瘤治疗的基本原则,5年生存率由原来单纯手术的20%提高到60%-70%。2骨肿瘤的保肢手术技术保肢手术治疗模式:新辅助化疗-手术-辅助化疗。肿瘤瘤段切除灭活再植、同种异体骨移植、自体骨带血管移植、旋转成形术、关节融合术、关节置换术。不同保肢手术的问题:灭活再植后生长能力丧失,异体骨愈合困难、不存活,移植自体骨的吸收,社会伦理问题,关节     

同种异体骨复合自体红骨髓移植治疗关节周围骨折

背景：关节周围骨折复位后常出现骨缺损,需进行植骨填充骨缺损以早期支撑关节面以防止关节面塌陷及移位。同种异体骨是治疗骨缺损的移植材料,但成骨能力差。自体红骨髓有成骨能力,但同种异体骨复合自体红骨髓移植治疗关节周围骨折的临床效果有待评定。 目的：采用锁定板固定、同种异体骨复合自体红骨髓移植治疗关节周围骨折的临床效果。 方法：纳入河北医科大学第三医院骨伤科治疗关节周围骨折患者43例。采用切开解剖复位关节面、将红骨髓与同种异体骨颗粒复合体植于骨缺损处,植骨完成后常规解剖锁定板内固定。胫骨平台骨折采用内侧、外侧或双侧锁定板固定。桡骨远端骨折采用背侧或掌侧锁定板固定,胫骨远端骨折采用胫骨远端内侧或外侧板锁定内固定。 结果与结论：患者43例共随访12个月至6年,平均4.3年。X射线片及CT复查结果显示,43例患者达骨性愈合,塌陷骨折复位良好。其中新鲜骨折愈合时间2-6个月,平均4个月;陈旧骨折愈合时间3-7个月,平均5.5个月。植骨后43例患者无明显免疫排斥反应,2例患者切口渗液较多,经换药2周愈合。切口感染患者1例,经引流换药4周伤口愈合,随访4年1个月至今感染未复发。根据Mankin和Komender标准评定,同种骨移植满意患者40例,占93%;不满意患者3例,占7%。结果证实,在锁定板支撑固定下,异体松质骨与自体红骨髓复合体移植治疗周围关节骨折可以起到近期支撑作用,防止关节面塌陷及骨折移位,并为关节周围骨折骨缺损提供骨重建材料,远期可以达到骨折愈合的目的。     

微骨折技术与骨软骨移植治疗关节软骨缺损

背景：关节镜下微骨折治疗与骨软骨移植是关节软骨缺损主要的治疗方法之一,具有广阔的应用前景。 目的：探讨关节镜下微骨折治疗与自体和同种异体骨软骨移植治疗膝骨关节炎合并关节软骨缺损的效果。 方法：应用关节镜下微骨折治疗清理术结合软骨缺损区微骨折术治疗膝骨关节炎的临床疗效、临床症状及Tegner运动评级判定疗效并随访观察3-24个月。自体骨软骨移植治疗关节软骨缺损的患者进行观察随访,通过评价移植后关节活动度、临床症状的改善、关节影像学检查等评估自体骨软骨移植治疗的效果。并对同种异体骨软骨移植治疗关节软骨缺损进行动物实验研究,通过对移植部位的大体观察、组织学观察以及免疫组织化学染色观察,评估同种异体骨软骨移植治疗的效果。 结果与结论：关节软骨缺损应用关节镜下微骨折治疗后的患者,关节清理术结合软骨缺损区微骨折术总有效率89.7%。关节软骨缺损应用自体骨软骨移植治疗后的患者,关节疼痛、肿胀的症状改善,关节活动度正常,偶有关节静息痛或活动后轻微疼痛,影像学检查见移植骨软骨位置良好,修复愈合良好。关节软骨缺损应用同种异体骨软骨移植治疗后的实验动物,关节活动度正常,移植关节面光整,关节软骨被透明软骨覆盖,细胞有序排列,软骨基质分泌,修复软骨Ⅱ型胶原免疫组织化学染色强阳性。     

大鼠皮肤移植排异反应中T淋巴细胞亚群的观察

为了了解在皮肤移植组织排异反应中浸润的不同T淋巴细胞亚群 ,分析其与排异反应的关系。采用HE及免疫组化方法观察大鼠III度烫伤后 2 0例同种异体 自体皮肤混合移植和 15例大张同种异体皮肤移植组织在移植后 4或 5、 7、 14、 2 1和 2 8d时CD4+ 和CD8+ 淋巴细胞的比例。结果表明同种异体 自体皮肤混合移植组 7～ 14d时CD8+ 淋巴细胞明显高于大张同种异体皮肤移植组 (P <0 0 5 ) ,在移植后 4或 5dCD4+ 淋巴细胞明显高于CD8+ 淋巴细胞。大张同种异体皮肤移植组在移植后 7～ 14dCD4+ 淋巴细胞明显高于CD8+ 细胞 ,在植皮后 7～ 2 8d高于同种异体 自体皮肤混合移植组 ,2 1d时差异有统计学意义 (P <0 0 5 )。在 7～ 14d时CD4/CD8比值高于同种异体 自体皮肤混合移植组 (P <0 0 5 )。提示同种异体 自体皮肤混合移植排异反应以CD8+ 淋巴细胞为主 ,而在大张同种皮肤移植排异反应中CD4+ 淋巴细胞起主要作用。     

同种异体骨移植与自体骨移植修复四肢粉碎性骨折:骨性愈合及骨活性比较

背景:骨移植是一种治疗四肢粉碎性骨折常用的方法,并且可以选择同种异体骨移植或者自体骨移植,两种骨移植方法各有优缺点。目的:对比同种异体骨移植与自体骨移植修复四肢粉碎性骨折在骨性愈合及骨活性方面的临床效果。方法:回顾性分析49例四肢粉碎性骨折患者的临床资料,按照骨移植方法分为观察组与对照组,观察组采用同种异体骨移植修复,对照组采用自体骨移植修复。观察两组骨折临床愈合时间、骨性愈合时间及骨特异性碱性磷酸酶活性,并进行比较。结果与结论:观察组骨折愈合时间及骨性愈合时间分别为(5.8±1.2)周、(5.8±1.5)个月,对照组骨折愈合时间及骨性愈合时间分别为(6.1±1.3)周、(6.1±0.8)个月,两组间骨折愈合时间及骨性愈合时间比较差异无显著性意义(P0.05);观察组与对照组骨特异性碱性磷酸酶活性分别为(10.45±1.53),(13.58±1.69)μg/L,两组间比较差异有显著性意义(P0.05)。表明同种异体骨移植与自体骨移植修复四肢粉碎性骨折均可获得良好的临床疗效,但自体骨移植在促进骨骼愈合能力方面有一定的优势。     

自体与同种异体肌腱重建膝关节前交叉韧带的比较

背景：关节镜辅助下重建前交叉韧带的移植物主要有自体移植物、同种异体移植物和人工韧带3种,关于移植物的选择,存在较多争议。 目的：评估自体健侧腘绳肌腱和同种异体肌腱两种移植物在膝关节前交叉韧带重建中的效果。 方法：纳入2007-01/2009-01在承德医学院附属医院骨科就诊的经关节镜检查证实为前交叉韧带损伤的患者70例(70膝),分别采用自体健侧腘绳肌腱和同种异体肌腱重建前交叉韧带,记录膝关节Lysholm功能评分、KT-1000测量值及不良反应。 结果与结论：患者随访18~24个月,均未发生血管神经损伤,无感染、植入物断裂等并发症;同种异体肌腱移植患者有2例膝关节引流管口持续渗出,经换药半月后愈合,其余切口均一期愈合。末次随访时,自体健侧腘绳肌腱和同种异体肌腱重建患者的Lysholm评分均显著提高,双侧膝关节前向松弛度差值显著减少,且两种方法比较差异无显著性意义(P > 0.05)。说明应用自体健侧腘绳肌腱与同种异体肌腱重建膝关节前交叉韧带疗效相当,效果满意。     

Antigenicity of cryopreserved arterial allografts: comparison with fresh and glutaraldehyde treated grafts

The use of cryopreserved aortic allografts in cardiovascular surgery is widespread and has resulted in excellent outcomes. However, it is controversial whether cryopreservation suppresses the antigenicity of tissue. We designed experimental models to study whether the cryopreservation process alters antigenicity in comparison with that found in fresh and glutaraldehyde treated tissues. Fresh, cryopreserved, and glutaraldehyde treated thoracic aorta from Brown Norway rats were subcutaneously implanted into Lewis rats. Inflammatory cells infiltrating around the grafts were measured on days 7, 14, 28, and 56 after implantation. The glutaraldehyde treated grafts showed significantly less infiltration than the fresh or cryopreserved grafts (p < 0.005). No significant difference was detected between the fresh and cryopreserved grafts. Another study examined the effect of modifications of the aortic allograft on subsequent allogeneic skin graft antigenicity. Subcutaneous implantation of fresh, cryopreserved, and glutaraldehyde treated aortic grafts from Brown Norway into Lewis rats resulted in subsequent skin graft rejection at 4.4+/-0.7, 5.1+/-0.8, and 6.6+/-2.1 days, respectively. There was no significant difference between the fresh and cryopreserved groups; whereas skin grafts in the glutaraldehyde group survived longer than those in the cryopreserved group. These results indicate that cryopreservation had no significant influence on antigenic suppression of arterial allografts.     

In vivo and in vitro comparison of three different allografts vitalized with human mesenchymal stromal cells

Bone allografts are commonly used by orthopedists to provide a mechanical support and template for cellular colonization and tissue repair. There is an increasing demand for bone graft substitutes that are safe and easy to store but which are equally effective in supporting new bone growth. In this study, we compared three different human bone allografts: (1) the cryopreserved allograft (frozen), (2) the gamma-irradiated and cryopreserved allograft (γ-irradiated), and (3) the solvent dehydrated and γ-irradiated-processed bone allograft (Tutoplast(?) Process Bone [TPB]). Human mesenchymal stromal cells (hMSCs) have the potential to differentiate into osteogenic, chondrogenic, and adipogenic lineages. Our results showed that hMSC seeding efficiency was equivalent among the three bone allografts. However, differences were observed in terms of cell metabolism (viability), osteoblastic gene expression, and in vivo bone formation. Frozen allografts had the higher frequency of new bone formation in vivo (89%). Compared with frozen allografts, we demonstrated that TPB allografts allowed optimal hMSC viability, osteoblastic differentiation, and bone formation to occur in vivo (72%). Further, the frequency of successful bone formation was higher than that obtained with the γ-irradiated allograft (55%). Moreover, after hMSC osteoinduction, 100% of the TPB and frozen allografts formed bone in vivo whereas only 61% of the γ-irradiated allografts did. As healthcare teams around the world require bone-grafting scaffolds that are safe and easy to store, the TPB allograft appears to be a good compromise between efficient bone formation in vivo and convenient storage at room temperature.     

Study of the healing process after transplantation of pasteurized bone grafts in rabbits

Different bone allografts (pasteurized, autoclaved, and frozen) were compared based on their osteoinductive properties. Our primary purpose was to examine the biologic qualities of pasteurized allografts, as pasteurization inactivates most viruses transmitted by transplantation. Frozen, pasteurized, and autoclaved allografts were packed into a standard defect of rabbit ulna. The animals were sacrificed at 2 and 4 weeks after surgery. The parts of bones with experimental defects were explored en bloc, and a roentgenogram was carried out. Ulna bone samples were then embedded in methyl-methacrylate. Roentgenograms showed that after 2 weeks, calluses were well-formed, but irregular in shape in all 3 types of allografts. After 4 weeks, the calluses were regular in shape in all but the autoclaved grafts. After 2 weeks, the healing processes had begun in the frozen and pasteurized grafts, with the reaching approximately the same stage, while in the autoclaved grafts these processes were not seen and the bone particles were surrounded by connective tissue without any changes. After 4 weeks, osteoinductive processes were very strong, with the first signs of complete bone remodeling at the bone edges of the defect in pasteurized and frozen allografts. The osteoinductive values of these 2 types were very high and similar. Autoclaved allografts, on the other hand, had very low osteoinductive values, as they were still at the very beginning of the healing process. Histomorphometric analysis revealed a significant difference in both newly formed osteoid thickness and osteoblast number per microm of bone surface in all experimental groups (P < 0.005). Values of osteoid thickness and osteoblast number were significantly higher in both frozen and pasteurized grafts when compared with the autoclaved ones (P < 0.005). Osteogenic properties of pasteurized bone allografts were preserved, and the allografts have been gradually replaced with newly formed bone. As such, pasteurized bone grafts from a bone bank have approximately the same biologic validity as frozen grafts, while autoclaved grafts impair bone healing.     

Effective use of optimized, high-dose (50 kGy) gamma irradiation for pathogen inactivation of human bone allografts

The safety of tissue allografts has come under increased scrutiny due to recent reports of allograft-associated bacterial and viral infections in tissue recipients. We report that 50 kGy of gamma irradiation, nearly three times the dose currently used, is an effective pathogen inactivation method when used under optimized conditions that minimize damage to the tissue. Cancellous bone dowels treated with a radioprotectant solution and 50 kGy of optimized irradiation had an ultimate compressive strength and modulus of elasticity equal to conventionally irradiated (18 kGy) and non-irradiated control bone grafts. We subjected bone dowels treated with this pathogen inactivation method to an in vitro cytotoxicity test using three different mammalian cell lines and concluded that the treated grafts were not cytotoxic. The log reduction of nine pathogens spiked into radioprotectant-treated bone irradiated to 50 kGy was also tested. We achieved 4.9 logs of inactivation of a model virus for HIV and hepatitis C and 5 logs inactivation of a model virus for human parvovirus B-19. Complete inactivation (6.0-9.2 logs) of seven clinically relevant microorganisms was demonstrated. The results show that a combination of radioprotectants and optimized, high-dose gamma irradiation is a viable method for producing safer cancellous bone grafts that have the mechanical strength of existing grafts.     

Prostaglandin E1 and recombinant bone morphogenetic protein effect on strength of hydroxyapatite implants.

Although combinations of hydroxyapatite (HAP) and bone morphogenetic protein (BMP) are expected to provide potent alternatives to autogenous bone grafts, it is still anticipated that substances that act synergistically with BMP will be found because the inducing potential of purified BMP in bone is not strong enough. We already have shown that prostaglandin (PG) E1 has a strong and dose-dependent synergistic effect on the osteoinductive activity induced by recombinant human (rh) BMP and that it enhances osteoconduction even when used alone. In this study, porous HAP rods were treated as follows: (1) without PGE1 or rhBMP (control group); (2) with varying concentrations of PGE1; and (3) with varying concentrations of PGE1 combined with 1 microg of rhBMP-2. The rods were subperiosteally implanted on the cranial bone of rabbits to evaluate the effect of these treatments on the mechanical strength of the implanted HAP rods. The HAP rods were removed 3, 6, or 9 weeks after implantation and subjected to mechanical strength determinations. The control group (no addition of BMP to the rods) showed no significant increase in three-point bending strength or in compression strength compared to pre-implantation. On the other hand, PGE1 combined with rhBMP had a strong and dose-dependent effect on the mechanical strength of HAP, increasing it significantly, especially compression strength. PGE1 also increased mechanical strength even when used alone. Histological examination revealed that PGE1, whether or not it was combined with rhBMP, increased bone formation into the pores of HAP and consequently increased the mechanical strength of porous HAP.     

Mechanical environment affects allograft incorporation

In a bilateral canine tibial model, the mechanical, radiologic, and histologic characteristics of intercalary allografts stabilized with locked intramedullary nails were compared with those of allografts fixed with compression plates. Both methods of fixation achieved healing to host bone. Tibiae that were plated had more callus with statistically greater mean torsional rigidity and strength than those treated with nails (paired t-test, p 相似文献   

实验性冷冻保存带血管的同种异体骨移值

为探讨应用吻合血管的冷冻保存同种异体肋骨移植修复骨缺损的可能性，以15％二甲基甲砜(DMSO)作为低温保护剂，采用两步玲冻步骤，对狗的含后肋问血管的肋骨段进行冷冻处理，在液氟中保存96h后，施行同种异体移植于髂嵴骨缺损区。术后3周内使用免疫抑制剂。对移植体进行免疫学(白细胞个素Ⅱ、T细胞亚群)监测，SPECT扫描、血管造影和病理学分析。实验结果表明，同种异体移植肋骨段血循环丰富，骨细胞代谢活跃，未发生急性排斥反应，3个月达骨性愈台，取得了类似于吻合血管的自体骨移植的效果。     

降温速度对冷冻保存异体小静脉通畅率的影响

目的:探讨不同降温速度对异体小静脉内皮细胞代谢活性,超微结构和移植通畅率的影响。材料和方法:采用快速冷冻和二步冷冻两种不同的降温速度对异体小静脉进行冷冻,在液氮中保存48小时后施行移植。观察方法包括四唑盐还原试验、扫描电镜、静脉造影及病理检查。结果:经二步冷冻保存的异体小静脉,其代谢活性和内皮细胞形态得到良好保持,移植后排斥反应减弱,90天通畅率80％。结论:二步冷冻降温是异体小静脉冷冻保存理想的方法。     

Fabrication and characterization of three-dimensional electrospun scaffolds for bone tissue engineering

When traumatic injury, tumor removal, or disease results in significant bone loss, reconstructive surgery is required. Bone grafts are used in orthopedic reconstructive procedures to provide mechanical support and promote bone regeneration. In this study, we applied a heat sintering technique to fabricate 3D electrospun scaffolds that were used to evaluate effects of mineralization and fiber orientation on scaffold strength. We electrospun PLLA/gelatin scaffolds with a layer of PDLA and heat sintered them into three-dimensional cylindrical scaffolds. Scaffolds were mineralized by incubation in 10× simulated body fluid for 6, 24, and 48 h to evaluate the effect of mineralization on scaffolds compressive mechanical properties. The effects of heat sintering hydroxyapatite (HA) microparticles directly to the scaffolds on mineral deposition, distribution and mechanical properties of the scaffolds were also evaluated. We found that orientation of the fibers had little effect on the compressive mechanical properties of the scaffolds. However, increasing the mineralization times resulted in an increase in compressive mechanical properties. Also, the direct addition of HA microparticles had no effect on the scaffold mechanical properties, but had a significant effect on the mineral deposition on PLLA/gelatin scaffolds.     

Porous poly(propylene fumarate) foam coating of orthotopic cortical bone grafts for improved osteoconduction

A porous biodegradable scaffold coating for perforated and demineralized cortical bone allografts could maintain immediate structural recovery and subsequently allow normal healing and remodeling by promoting bony ingrowth and avoiding accelerated graft resorption. This new type of osteoconductive surface modification should improve allograft incorporation by promoting new bone growth throughout the biodegradable scaffold, hence encasing the graft with the recipient's own bone. We investigated the feasibility of augmenting orthotopically transplanted cortical bone grafts with osteoconductive biodegradable polymeric scaffold coatings. Five types of bone grafts were prepared: type I, untreated fresh-frozen cortical bone grafts (negative control); type II, perforated and partially demineralized cortical bone grafts without additional coating (positive control); type III, perforated and partially demineralized cortical bone coated with a low-porosity poly(propylene fumarate) (PPF) foam; type IV, perforated and partially demineralized cortical bone coated with a medium-porosity PPF foam; and type V, perforated and partially demineralized cortical bone coated with a high-porosity PPF foam. Grafts were implanted into the rat tibial diaphysis. Fixation was achieved with an intramedullary threaded K-wire. Two sets of animals were operated on. Animals were killed in groups of eight with one set being killed 12 weeks, and the other 16 weeks, postoperatively. Radiographic, histologic, and histomorphometric analyses of grafts showed that the amount of new bone forming around the foam-coated grafts was significantly higher than that in the type I control group (uncoated) or that in type II group (perforated and partially demineralized cortical bone grafts). Although all foam formulations appeared initially equally osteoconductive, histologic evaluation of medium-porosity PPF foam-based coatings appeared to result in a sustained response 16 weeks postoperatively. Significant resorption was present in perforated and partially demineralized cortical bone graft allografts, with some accompanying new bone formation occurring primarily within the laser holes. Therefore, PPF foam-coated cortical bone grafts appeared to be better protected from excessive bone resorption, as frequently seen with invasion of fibrovascular tissue. Biomechanical analysis of the PPF foam-coated grafts corroborated findings of the morphometric analysis in that the failure strength at the allograft-host bone junction sites of all PPF-coated cortical bone grafts was higher than in the uncoated controls.