Donor site reconstruction in iliac crest tricortical bone graft: surgical technique

Background and purposeAutogenous bone grafts from the iliac crest are frequently harvested for autologous bone transplantation, because this is still the gold standard in the treatment of many bone defects. However, significant donor site morbidity must be considered. We have developed a simple method to treat the bone defect in the donor site in order to reduce some of the morbidity. In this method, the bone defect size and shape determines its application.MethodAfter the conventional method of tricortical bone harvesting from the iliac crest, bone defect is repaired by means of a transversal fence of appropriate thin tricortical chips obtained from the posterior lateral wall of the bone defect itself. The mechanical stability of this fence results from impactation of the ends of the tricortical chips into both lateral cancellous bone walls of the repaired bone defect. Thus, no hardware is required, and both the bone defect and ilium contour are restored.ResultsThis simple method allows ilium bone defect healing and bone contour recovery after graft harvest, by using the same gold standard graft. Although not much time is necessary to reconstruct the donor site, the bone defect size and shape determine its application.InterpretationThis method may be a recommendable option for bone defect reconstruction after iliac crest tricortical bone graft harvest as the primary procedure. The advantages of this technique are bone defect healing and bone contour restoration with prevention of a visible deformity over the groin, with no foreign material insertion, thus avoiding additional cost.     

Recombinant human bone morphogenetic protein-2: a novel osteoinductive alternative to autogenous bone graft?

Autogenous bone grafts from the iliac crest have long been the gold standard for repair and reconstruction of bone; however harvesting of the grafts from the iliac crest is associated with donor site morbidity, particularly chronic pain. The bone morphogenetic proteins (BMPs) are soluble bone matrix glycoproteins that induce the differentiation of osteoprogenitor cells into osteogenic cells and have the potential to act as autogenous bone graft substitutes. BMP-2, which can be produced with recombinant technology, is highly osteoinductive, inducing bone formation by stimulating the differentiation of mesenchymal cells into chrondroblasts and osteoblasts. At present, more than 1,000 patients have received rhBMP-2 in clinical trials for acute open tibial fracture and interbody fusion procedures for the treatment of degenerative disc disease. Data suggest that rhBMP-2 therapy may offer an effective alternative to autogenous bone graft for recalcitrant bone unions and spinal fusion, obviating donor site morbidity.     

Repair of the abdominal donor-site fascial defect with small intestinal submucosa (Surgisis) after TRAM flap breast reconstruction

We report the successful use of Surgisis in the repair of the abdominal donor site fascial defect following a free transverse rectus abdominis myocutaneous (TRAM) flap breast reconstruction. No abdominal wall weakness in the flap donor site was evidenced by a series of clinical examinations to at least 14 months after Surgisis placement. A well-formed and thickened fascial layer at the abdominal donor fascial repair site was revealed by computed tomography scan. This objective finding, along with our clinical observation, supports the use of Surgisis for repair of the abdominal donor site fascial defect following a TRAM flap harvesting.     

Use of the calvarium for bone grafting in cranio-maxillo-facial surgery

Bone grafts's traditional donor sites in cranio-maxillo-facial surgery have been for many years and are still in some occasions the ribs, iliac crest and tibia. Bone grafts taken from the calvaria have been used by some surgeons in the past but its wide acceptance was only achieved after Paul Tessier had reported his own experience. The calvaria is composed of inner and outer tables that encloses a layer of cancellous bone called the diploe. A high degree of variability exist with respect to skull thickness. Nevertheless parietal bones is the preferable site for the harvesting of the graft. The embryonic origin of the cranium should be responsible for greater survival of the graft. Membranous bone would maintain its volume to a greater extent than endochondral bone when autografted in the cranio-facial region. However this remains controversial. Two techniques can be used for the harvesting of a calvarial bone grafts. A split thickness calvarial graft involves removal of the outer table while leaving the inner layer in place. Its main disadvantage is the relatively thinness of the bone transferred. A full thickness segment of skull involves the cranium cavity be entered. A half of the graft can be split along the diploe space and returned to fill the donor site. The other half is used for reconstruction. It is a more complicated procedure. Cranial grafts have been used in the following cases. Correction of contour defect of the forehead and zygomatic bones, orbital floor reconstruction, restoration of the nasal bridge, bone grafting of the maxilla and mandibule. The advantages are the following: the donor and recipient sites are in adjacent surgical fields, the donor site scar is hidden in the scalp, morbidity associated with removing the graft is almost inexistent. (ABSTRACT TRUNCATED AT 250 WORDS)     

Vascularized bone grafts for upper limb reconstruction: defects at the distal radius, wrist, and hand

Vascularized bone grafts have been successfully applied for the reconstruction of bone defects at the forearm, distal radius, carpus, and hand. Vascularized bone grafts are most commonly used in revision cases in which other approaches have failed. Vascularized bone grafts can be obtained from a variety of donor sites, including the fibula, the iliac crest, the distal radius (corticocancellous segments and vascularized periosteum), the metacarpals and metatarsals, and the medial femoral condyle (corticoperiosteal flaps). Their vascularity is preserved as either pedicled autografts or free flaps to carry the optimum biological potential to enhance union. The grafts can also be transferred as composite tissue flaps to reconstruct compound tissue defects. Selection of the most appropriate donor flap site is multifactorial. Considerations include size matching between donor and defect, the structural characteristics of the graft, the mechanical demands of the defect, proximity to the donor area, the need for an anastomosis, the duration of the procedure, and the donor site morbidity. This article focuses on defects of the distal radius, the wrist, and the hand.     

Fractured coracoid with anterior shoulder dislocation and greater tuberosity fracture--report of a bilateral case

We treated 23 patients with recalcitrant posttraumatic humeral shaft nonunion with vascularized bone grafts (fibula 10, femur 10 and scapula 3). 21/23 patients healed primarily. Venous thrombosis in the graft necessitated postoperative thrombectomy in 2 patients. Complications at the donor site were trivial. We used a vascularized fibular graft in patients with a large bone defect and with poor intrinsic stability of the nonunion site and a corticoperiosteal femoral graft in atrophic nonunion without a substantial bone defect. The scapula graft is easy to transfer to the surgical neck of the humerus on its pedicle.     

Experimental results of donor site filling for autologous osteochondral mosaicplasty

Purpose: Autologous osteochondral mosaicplasty has become a treatment option for focal chondral and osteochondral defects in recent years. Excessive postoperative bleeding from the donor site was reported as a possible complication of the procedure. The purpose of this study was to investigate different biodegradable materials for donor site filling, which could prevent excessive postoperative bleeding from these sites but would allow reasonable blood clot formation on the articular surfaces of donor tunnels. Type of Study: Basic science evaluation. Methods: In an experimental model, “donor site plugs” made from hydroxylapatite, carbon fiber, polyglyconate-B, compressed collagen, and 2 versions of polycaprolactones were used to fill the bony tunnels created by harvesting. These materials were tested in 100 knees of 50 German Shepherd dogs to determine the quality of the repair tissue formation on the surfaces of the harvesting holes filled by these materials. Arthroscopies of the dogs were performed at several intervals, from 4 weeks to 26 weeks, and macroscopic studies were performed on euthanized animals between 8 weeks and 30 weeks to evaluate donor site filling and coverage. Empty donor tunnels served as controls for the evaluation of the different filling materials. Results: All tested materials effectively decreased postoperative bleeding. Hydroxylapatite, carbon rods, polyglyconate-B, and melted polycaprolactone materials showed a good integration to the surrounding cancellous bone, but these fillings showed only a limited repair tissue formation, even at 30 weeks postoperatively. Second-look arthroscopy and histologic evaluation of necropsies showed the best fibrocartilage coverage after filling by compressed collagen. Technical details of the filling also had certain importance in the quality of the repair tissue formation. Conclusions: According to histologic results, compressed collagen appears to be a good material to fill donor tunnels of osteochondral graft harvest. This material is substituted gradually by bone formation and its articular surface can serve as an appropriate scaffold for fibrocartilage coverage created by the natural intrinsic repair process.     

Integration of periosteum covered autogenous bone grafts with and without autologous chondrocytes. An animal experiment using the Göttinger minipig

Autologous osteochondral transplantation has the major disadvantage of significant damage to a healthy joint surface at the donor site.The purpose of this study was to examine the effect of autogenous chondrocytes injected into the periosteum of autologous bone grafts in order to provide an alternative method for cartilagerepair. A total of 22 Göttinger minipigs were operated twice on both knees.The first operation served for cartilage biopsy for the chondrocyte culture.During the second operation an osteochondral defect was created in the medial facet of the trochlear groove.The defect was treated differently with an autologous cortico-cancellous bone cylinder,harvested from the proximal tibia.Group A: untreated defect (control);B: bone-graft;C: bone-graft covered with periosteum; D: bone-graft with periosteum and injected autologous chondrocytes.The animals were killed after 6,12,26 and 52weeks.The regenerated areas were evaluated macroscopically, tested biomechanically (long-term specimens; indentation-test) and a histological, blind evaluation was carried out according to a semi-quantitative scoring system. The periosteum covered bone cylinders in Groups C and D showed good repair of the bone and cartilage defect.The repaired tissue consisted predominantly of fibrocartilage with the partial formation of hyalin like tissue.The regenerated areas were integrated with the adjacent cartilage and were biomechanically superior when compared with the other groups. The additional injection of chondrocytes did not produce significantly better results. Our findings suggest that the transplantation of periosteum-covered bone cylinders may provide an alternative method for treating chondral and osteochondral defects and can be recommended for filling large donor site defects in joint surgery.The additional transplantation of chondrocytes does not seem to be justified.     

骨膜瓣复合开窗异体骨移植修复大段骨缺损

目的探讨带血管薄层皮质骨-骨膜瓣嵌入开窗的异体骨修复大段骨缺损的效果。方法将兔胫骨去抗原后制备异体骨标本,制作大段骨缺损动物模型,以带血管薄层皮质骨-骨膜瓣复合开窗的异体骨进行修复。术后观察骨缺损的X线影像,对移植物及其周围软组织行组织学和免疫组织化学观察。结果实验组骨缺损骨痂形成和改造塑形,新生血管长入骨缺损处,新骨形成和骨单位成熟较对照组早。结论以带血管薄层皮质骨-骨膜瓣嵌入开窗的异体骨修复大段骨缺损的手术方法优于以骨膜瓣直接包裹异体骨,缩短骨缺损修复的时间。     

RIA versus iliac crest bone graft harvesting: A meta-analysis and systematic review

BackgroundReamer-Irrigator-Aspirator (RIA) of long bones is increasingly being used as an alternative to iliac crest harvesting for bone-grafts. This meta-analysis compares both harvesting techniques with regard to donor site morbidity, healing potency and implantation site morbidity.MethodsPubMed/Medline/Embase/CENTRAL/CINAHL were searched for both randomized clinical trials (RCT) and observational studies. Effect estimates were pooled across studies using random effects models and presented as weighted odds ratio (OR) with corresponding 95% confidence interval (95%CI).ResultsA total of 5 studies were included. RIA carries a lower risk for chronic pain (0% versus 14.2%, OR 0.08, 95% CI 0.02 – 0.35) and infection (1% versus 5.9%, OR 0.29, 95% CI 0.09- 0.9) at the donor site compared to iliac crest harvesting. Iliac crest bone-harvesting has an inherent additional risk of neuropraxia of the lateral femoral cutaneous nerve and numbness of the scar which is not encountered in RIA harvesting. Risk for other reported complications such as hematoma and iatrogenic fractures appear equal in both groups. The clinical healing potential of both bone grafts, in terms of union rate (OR 1.53, 95%CI 0.62 – 3.75) at the implantation site and time-to-union (MD 0.44 months, 95%CI -1.72 – 0.83), seems equal.ConclusionThe main difference between RIA and iliac crest bone graft harvesting is the considerable higher risk of chronic pain of the pelvic procedure. Although risk for infection was also higher for the iliac crest group, the absolute difference is relatively small. Evidence suggests an equal healing potential of the grafts themselves irrespective of harvesting method.     

Cartilage repair with autogenic perichondrium cell and polylactic acid grafts

The repair of articular cartilage injuries remains a challenge, with many of the current therapeutic strategies based on the grafting or recruitment of chondrogenic tissues or cells. This 1-year study compared the repair of a 3.7-mm diameter by 3-mm deep osteochondral defect in the medial femoral condyle of 24 New Zealand White rabbits; the defect was obtained using an autogenic perichondrium cell polylactic acid composite graft with a contralateral control in which the osteochondral defect remained empty. To elucidate the effect of host immune responses on the repair process after perichondrium cell transplantation, the results of the autogenic perichondrium cell polylactic acid graft group were compared with those obtained in the authors' previous 1-year study of allogenic perichondrium cell polylactic acid composite grafts implanted in a similar model. One year after surgery, the repair site underwent gross inspection and histologic, histomorphometric, biochemical, and biomechanical analyses. The autogenic perichondrium cell polylactic acid graft group (92%) and the control group in which the osteochondral defect remained empty (88%) resulted in a high percentage of grossly acceptable repairs. The autogenic grafts appeared to augment the intrinsic healing capacity of the animals (as compared with the animals in the No Implant Group). The autogenic perichondrium cell polylactic and grafts improved the histologic appearance and percentage of Type II collagen of the cartilaginous repair tissue. Compared with allogenic grafts, the autogenic grafts had better reconstitution of the subchondral bone. However, the results of this experimental model suggest a suboptimal concentration of glycosaminoglycans in the neocartilage matrix, a depressed surface of the repair tissue, a histologic appearance that was not equivalent to that of normal articular cartilage, and reduced biomechanical properties for the repair tissue. The future application of growth factors to this model may yield a treatment that can be applied in the clinical arena.     

Complications after harvesting of autologous bone from the ventral and dorsal iliac crest - a prospective,controlled study

INTRODUCTION: In a prospective, controlled study, donor site morbidity after bone graft harvesting from the anterior and posterior iliac crest was documented. METHODS: In 113 patients, monocortical to tricortical bone grafts were taken from the anterior (n = 73) or dorsal (n = 40) iliac crest. Bone graft size (0.4 - 43 cm 3, median 9.7 cm 3), Operation time (12 - 65 minutes, median 28 minutes), and postoperative donor site were documented. RESULTS: Donor site morbidity was higher after harvesting from the ventral than from the dorsal iliac crest: total morbidity 48 vs. 32.5 %, large haematomas 9.6 vs. 7.5 %, moderate haematomas 34.3 vs. 15 %, wound dehiscence 2.7 vs. 0 %. One revision operation was necessary because of a large haematoma at the ventral crest. After harvesting from the ventral iliac crest, there was one fracture ofthe iliac wing and one avulsion fracture of the iliac crest. There were no infections, no injuries of arteries or of the lateral femoral cutaneous nerve and no hemiation. After harvesting from the dorsal iliac crest, there were no major complications. CONCLUSION: Bone graft harvesting from the posterior iliac crest should be preferred over harvesting from the anterior iliac crest beeause of the substantially reduced donor site morbidity. Harvesting from the ventral iliac crest should have a clear indication, synthetic bone substitutes should be taken into consideration.     

Full-thickness skin graft from the ulnar aspect of the wrist to cover defects on the hand and digits

Skin defects on the volar surface of the hand and digits are commonly treated with skin grafts. Many donor sites capable of providing adequate skin have already been reported. Ideal conditions for the donor site depend on skin color, texture, durability, and size. The authors describe the use of a new donor site for harvesting skin grafts to repair relatively small skin defects on the hand and digits. They used full-thickness skin grafts from the ulnar aspect of the wrist to reconstruct burn contractures and syndactyly in 20 patients. Their grafts provided an ideal color and texture match, and normal function of the hand and digits was restored. The donor site was closed directly, and the resulting scar was inconspicuous.     

Axially vascularized bone substitutes: a systematic review of literature and presentation of a novel model

Introduction

The creation of axially vascularized bone substitutes (AVBS) has been successfully demonstrated in several animal models. One prototypical indication is bone replacement in patients with previously irradiated defect sites, such as in the mandibular region. The downside of current clinical practice, when free fibular or scapular grafts are used, is the creation of significant donor site morbidity.

Methods

Based on our previous experiments, we extended the creation of an arterio-venous loop to generate vascularized bone substitutes to a new defect model in the goat mandibula. In this report, we review the literature regarding different models for axially vascularized bone substitutes and present a novel model demonstrating the feasibility of combining this model with synthetic porous scaffold materials and biological tissue adhesives to grow cells and tissue.

Results

We were able to show the principal possibility to generate axially vascularized bony substitutes in vivo in goat mandibular defects harnessing the regenerative capacity of the living organism and completely avoiding donor site morbidity.

Conclusion

From our findings, we conclude that this novel model may well offer new perspectives for orthopedic and traumatic bone defects that might benefit from the reduction of donor site morbidity.     

Useful Adjuncts to Harvest Split-Thickness Skin Grafts

Background. Split-thickness skin grafts are useful for repair of defects that are not amenable to primary closure or secondary intention healing. Because of the thinness of split-thickness skin grafts, damage to the graft and curling are common with standard harvesting techniques. Adjunctive methods for harvesting split-thickness skin grafts have not been well elucidated in the literature.
Methods. Lubrication and a tongue depressor facilitate even harvesting of the split-thickness skin graft. A semipermeable membrane is applied to the split-thickness skin graft donor site before harvesting the skin graft. This aids with harvesting and minimizes trauma to the graft.
Conclusion. Use of lubrication, a tongue depressor, and a semipermeable membrane are useful adjuncts to harvesting split-thickness skin grafts.     

Aesthetic closure of the donor site of a radial forearm free flap with two local curved skin grafts

The authors have designed an aesthetic and effective coverage technique using local curved skin grafts along with vascular pedicles without additional skin incisions to solve the disadvantages of skin coverage problem of donor site defect after radial forearm free flap (RFFF) harvesting. This has, to the authors’ knowledge, not been previously described.     

Cavernous nerve regeneration using acellular nerve grafts

INTRODUCTION: The restoration of erectile function following complete transection of nerve tissue during surgery remains challenging. Recently, graft procedures using sural nerve grafts during radical prostatectomy have had favorable outcomes, and this has rekindled interest in the applications of neural repair in a urologic setting. Although nerve repair using autologous donor graft is the gold standard of treatment currently, donor nerve availability and the associated donor site morbidity remain a problem. In this study, we investigated whether an "off-the-shelf" acellular nerve graft would serve as a viable substitute. We examined the capacity of acellular nerve scaffolds to facilitate the regeneration of cavernous nerve in a rodent model. MATERIALS AND METHODS: Acellular nerve matrices, processed from donor rat corporal nerves, were interposed across nerve gaps. A total of 80 adult male Sprague-Dawley rats were divided into four groups. A 0.5-cm segment of cavernosal nerve was excised bilaterally in three of the four groups. In the first group, acellular nerve segments were inserted bilaterally at the defect site. The second group underwent autologous genitofemoral nerve grafts at the same site, and the third group had no repair. The fourth group underwent a sham procedure. Serial cavernosal nerve function assessment was performed using electromyography (EMG) at 1 and 3 months following initial surgery. Histological and immunocytochemical analyses were performed to identify the extent of nerve regeneration. RESULTS: Animals implanted with acellular nerve grafts demonstrated a significant recovery in erectile function when compared with the group that received no repair, both at 1 and 3 months. EMG of the acellular nerve grafts demonstrated adequate intracavernosal pressures by 3 months (87.6% of the normal non-injured nerves). Histologically, the retrieved regenerated nerve grafts demonstrated the presence of host cell infiltration within the nerve sheaths. Immunohistochemically, antibodies specific to axons and Schwann cells demonstrated an increase in nerve regeneration across the grafts over time. No organized nerve regeneration was observed when the cavernous nerve was not repaired. CONCLUSION: These findings show that the use of nerve guidance channel systems allow for accelerated and precise cavernosal nerve regeneration. Acellular nerve grafts represent a viable alternative to fresh autologous grafts in a rodent model of erectile dysfunction.     

微小颗粒骨移植骨细胞活性的实验研究

目的 观察微小颗粒骨在移植修复骨缺损过程中的骨细胞存活情况和生物活性. 方法 建立大鼠桡骨骨缺损模型,近交系DA大鼠88只,其中雄性大鼠28只,作为供体;雌性大鼠60只,作为受体.将受体随机分为块状骨组(n=56)、微小颗粒骨组(n=56)和空白对照组(n=4),取雄性大鼠髂骨为供体骨,分别制成直径为2mm的骨块和直径为300～500 μm的微小颗粒骨,植入骨缺损,于术后1 d、4 d、1周、2周、4周、6周、10周取材,采用原位杂交的方法观察受体内Y染色体性别决定基因(Sry)的表达情况,应用免疫组化法观察各组骨形态发生蛋白-2(BMP～2)、转化生长因子-β1(TGF-β1)、碱性磷酸酶(ALP)和I型胶原的表达情况. 结果 块状骨组在移植早期Srv的表达逐渐减少,至1周消失,4周后再次出现,并且随时间延长表达逐渐增多;微小颗粒骨组各时间段均有Sry的表达,在同一时间点,微小颗粒骨组Sry的阳性细胞数多于块状骨组(P<0.05),两种骨移植物中参与修复骨缺损的细胞类型不同.微小颗粒骨内和周围组织中BMP-2、TGF-β1、ALP和Ⅰ型胶原的阳性细胞数在术后2周内多于块状骨组(P<0.05). 结论 微小颗粒骨与块状骨修复骨缺损时均有供体骨细胞参与,但微小颗粒骨内有更多的骨细胞存活.微小颗粒骨内存活的骨细胞具有生物学活性,合成并分泌骨生长因子和骨基质蛋白,可以加速骨缺损的修复.     

Serum albumin enhances bone healing in a nonunion femoral defect model in rats: a computer tomography micromorphometry study

Purpose

Blood-derived proliferative factors such as platelet rich plasma or activated plasma are promising adjuvants for bone grafts. Our earlier studies showed that serum albumin itself can markedly enhance the proliferation of stem cells on bone allograft and postulated that albumin coating alone may improve bone graft integration in vivo.

Methods

Two femoral defect models were performed in adult male Wistar rats. In the critical size model a six millimetre gap was created in the midshaft of the femur and fixed with plate and screws, while a nonunion model was established by the interposition of a spacer in the osteotomy for four weeks which resulted in compromised healing and nonunion. Albumin coated and uncoated grafts were placed into the defects. Bone healing and morphometry were evaluated by μCT and histology four weeks after implantation of the grafts.

Results

In the critical size model none of the bone grafts were able to bridge the defect, and graft resorption was the typical outcome. In the nonunion model regular uncoated grafts had a low union rate (two out of six), which increased markedly when albumin coating was applied (six out of eight). Trabecular thickness and pattern factor improved significantly in the albumin coated group versus uncoated or empty controls.

Conclusions

Our results showed that serum albumin coating of bone grafts can enhance the remodelling and efficacy of treatment in a nonunion model.