Use of demineralized allogeneic bone transplants for plastic surgery of osteomyelitic cavities

Plasty of osteomyelitic cavities with demineralized bone transplants was performed in 55 patients. Different methods of the bone cavity plasty were used with regard for the state of soft tissues surrounding the pathological focus, changes in the purulent focus. In most of the patients (41) the cavity was filled up with the demineralized bone transplant formed with special reference to the size of the bone wound. In the other 14 patients with false joints complicated by osteomyelitis the bone allotransplant was put in the area of the defect as a duplicator. Good results were obtained in 53 (96.4%) patients.     

Osteoinduction by implants of demineralized allogeneic bone matrix is diminished in vitamin D-deficient rats

Summary Experimental heterotopic bone formation was produced by subcutaneous implants of demineralized allogeneic bone matrix (DABM) in vitamin D-deficient (−D) animals that were either not treated or given vitamin D₃ (+D) or 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) to determine the role of vitamin D and its most active metabolite in osteoinduction and implant remodeling. Histologically, implants in both +D and −D groups caused a similar acute inflammatory response, formation of a fibrous capsule, and chondrogenesis by 1 to 2 weeks after implantation. However, by 3 weeks after implantation implants in the −D animals had formed less bone matrix, had developed a defect in matrix mineralization, had reduced bone forming and bone resorbing surfaces, and had altered bone architecture resulting from defective bone remodeling. The altered histology in −D animals was not corrected by 10 weeks after implantation. Treatment of vitamin D-deficient rats with 1,25(OH)₂D₃, 65 pmol/day for 3 weeks, corrected both the defect in mineralization and the abnormal histology. The results indicate that (1) vitamin D deficiency does not alter either the timing or the sequence of histologic events associated with osteoinduction but dramatically reduces the magnitude of the response, (2) vitamin D deficiency not only impairs mineralization but also reduces bone formation and resorption, and (3) 1,25(OH)₂D₃ mimics all of the actions of vitamin D with regard to correcting the abnormal osteoinductive response and bone histomorphometry.     

Cranioplasty using allogeneic perforated demineralized bone matrix with autogenous bone paste

The efficacy of allogeneic perforated demineralized bone matrix with autogenous bone paste in the treatment of full-thickness cranial defects was evaluated in 10 consecutive patients between June 1998 and December 1998. The skull defects resulted from trauma in 9 patients and removal of a cranial tumor in 1 patient. The size of the skull defects ranged from 8 x 6 cm to 11 x 12.5 cm. Follow-up averaged 33 months for all patients. Postimplantation evaluations included serial photographs, repeated physical examination, and three-dimensional computed tomography for all patients. Visual inspection of the implanted biomaterial 6 months later was possible in 1 patient. The contour of the reconstructed skull was acceptable aesthetically without any secondary depression noted during the follow-up period. Three-dimensional computed tomographic scans taken 2 years after implantation indicated that the allogeneic perforated demineralized bone matrix provided a matrix for new bone formation with remarkable osteoinductive potential for new bone formation. The autogenous bone paste was able to caulk the demineralized bone matrix and fill the contour irregularities and gaps of the reconstructed cranium. The results from this clinical study indicated that allogeneic perforated demineralized bone matrix with autogenous bone paste is a promising alternative to an autogenous bone graft and or alloplastic material for cranioplasty.     

Use of demineralized bone matrix in the extremities

Autologous bone graft is considered as the gold standard for all indications for bone grafting procedures but the limited availability and complications in donor site resulted in seeking other options like allografts and bone graft substitutes. Demineralized bone matrix (DBM) is an allograft product with no quantity limitation. It is an osteoconductive material with osteoinductive capabilities, which vary among different products, depending on donor characteristics and differences in processing of the bone. The purpose of the present review is to provide a critical review of the existing literature concerning the use of DBM products in various procedures in the extremities. Clinical studies describing the use of DBM alone or in combination with other grafting material are available for only a few commercial products. The Level of Evidence of these studies and the resulting Grades of Recommendation are very low. In conclusion, further clinical studies of higher quality are required in order to improve the Recommendation Grades for or against the use of DBM products in bone grafting procedures.     

Use of demineralized bone matrix in children

Eighty five clinical observations of the authors have shown autotransplants demineralized in the solution of hydrochloric acid to possess pronounced osteoinductive properties. Their ability to induce osteogenesis was mostly pronounced in simultaneous plasty with a demineralized and frozen bone. Reconstructive processes are perfectly completed within 18-24 months after operation.     

Neo-osseous flaps using demineralized allogeneic bone in a rat model

Surgical reconstruction with revascularized bone grafts can be compromised by donor tissue limitations and may be refined by prefabrication of compound neoflaps using bone substitutes. The principal suitability of demineralized allogeneic bone (DALB) slabs in fabricating neo-osseous flaps based on the inferior epigastric vascular system was studied and compared with neoflaps with autologous bone (AUB). In 45 rats, the histological pattern of bone formation in response to angiogenesis induced by vessel implantation was assessed, and characteristics of vascularization of the neoflap were studied microangiographically at 2, 4, 6, and 8 weeks. Histological techniques included decalcified and nondecalcified sections, as well as intravital polyfluorochrome labeling. Blood flow of the neoflap was also assessed quantitatively using 15-microm microspheres labeled with technetium 99-methylene diphosphate (99-MDP) 8 weeks after flap fabrication. Although the DALB neoflaps showed consistent bone formation and neovascularization, the bone regeneration process was delayed distinctly in comparison with AUB. Microangiographically, however, no differences between the two types of grafts became apparent during all time periods tested. Furthermore, the radioactivity of the DALB neoflap, which means bone blood flow per dry weight, was significantly higher than in AUB grafts and even more than that of intact iliac bone (p = 0.001). The exact meaning of elevated blood flow in DALB and similar degrees of vascularization corresponding to native AUB grafts remains to be determined, but may be a sign of ongoing bone formation resulting in a suitable DALB-containing neo-osseous flap in the long term. The authors findings support that allogeneic bone could be a potential substitute for AUB in creating a prefabricated neo-osseous flap.     

Surgical correction of breast deformities following long-lasting complications of polyurethane-covered implants

Breast deformities following long-lasting complications associated with the use of polyurethane prostheses are encountered with increasing frequency in our practice. Patients with this problem often feel frustrated after a long period of unsuccessful treatment and multiple operations. The anatomopathological bases of the deformity in such patients can be summarized as follows: volumetric mammary defect, soft tissue deficiency, and distortion and fibrosis of residual breast tissues. The reconstructive procedure should provide adequate aesthetic results with permanent or long-lasting symmetry, possibly in a single operative stage. The procedures employed in 12 patients are reviewed, and 3 representative cases are described in detail. The best aesthetic results in difficult cases have been achieved with either a latissimus dorsi muscular flap raised through minimal posterior incisions and transposed anteriorly to cover a permanent, expandable implant, or a suitably tailored, partly deepithelialized transverse rectus abdominis musculocutaneous flap.     

Incorporation of autoclaved autogeneic bone supplemented with allogeneic demineralized bone matrix. An experimental study in the rabbit

Resected, autoclaved, and reimplanted bone supplemented with allogeneic demineralized bone matrix (DABM) was compared with nonsupplemented bone in the reconstruction of bilateral ulnar defects in seven adult rabbits. The reconstructions were studied in vivo with the use of serial radiography, scintigraphy (99mTc-MDP), and bone mineral determination. After sacrifice at 16 weeks, the ulnar specimens were analyzed with the use of high-resolution radiography, autoradiography (45Ca), and histologic study. Scintigraphically, the uptake was significantly higher in the DABM-supplemented implants during the entire investigation. Bone mineral content was significantly higher at four and eight weeks in the DABM-supplemented implants, compared with the nonsupplemented implants, but later it equalized. New bone formation, as reflected by 45Ca incorporation, still occurred at 16 weeks in both types of implants, but it was more intense in the DABM-supplemented ones. Radiography and histologic analysis showed more new bone in the DABM-supplemented reconstructions than in the nonsupplemented ones. High-resolution radiography showed complete incorporation of all seven DABM-supplemented implants, whereas there was nonunion in five of seven nonsupplemented reconstructions. The current study indicates that resected, autoclaved, and reimplanted diaphyseal segments supplemented with demineralized allogeneic bone matrix incorporate better than nonsupplemented implants of autoclaved autologous bone.     

Hand reconstruction with allograft demineralized bone: twenty-six implants in twelve patients.

A long-term study of 26 phalangeal or metacarpal defects that were reconstructed with allogeneic demineralized bone implants demonstrates healing comparable to that which follows autogenous bone grafting. Average follow-up was 54 months. Five patients had multiple enchondromas (Ollier's syndrome), five children had congenital hand deformities, and all of these had previously had bone grafts harvested for associated craniofacial reconstructions. With the use of demineralized bone implants, tourniquet and operative times were significantly reduced and potential donor site morbidity was eliminated. Further, regional anesthesia was used more frequently and hospitalization time was reduced. There were no postoperative complications. Demineralized bone implants have been particularly useful in patients who previously had refused bone grafting.     

Use of demineralized bone matrix in spinal fusion

Spinal fusion remains the gold-standard treatment for several pathological spine conditions. Although, autologous Iliac Crest Bone Grafting is considered the gold-standard graft choice to promote spinal fusion; however, it is associated with significant donor site morbidity and a limited graft quantity. Therefore, several bone graft alternatives have been developed, to augment arthrodesis. The purpose of this review is to present the results of clinical studies concerning the use of demineralized bone matrix (DBM), alone or as a composite graft, in the spinal fusion. A critical review of the English-language literature was conducted on Pubmed, using key word “demineralized bone matrix”, “DBM”, “spinal fusion”, and “scoliosis”. Results had been restricted to clinical studies. The majority of clinical trials demonstrate satisfactory fusion rates when DBM is employed as a graft extender or a graft enhancer. Limited number of prospective randomized controlled trials (4 studies), have been performed comparing DBM to autologous iliac crest bone graft in spine fusion. The majority of the clinical trials demonstrate comparable efficacy of DBM when it used as a graft extender in combination with autograft, but there is no clinical evidence to support its use as a standalone graft material. Additionally, high level of evidence studies are required, in order to optimize and clarify the indications of its use and the appropriate patient population that will benefit from DBM in spine arthrodesis.     

Combined technique for the correction of lower-limb deformities resulting from metabolic bone disease

We present the results of the surgical correction of lower-limb deformities caused by metabolic bone disease. Our series consisted of 17 patients with a diagnosis of hypophosphataemic rickets and two with renal osteodystrophy; their mean age was 25.6 years (14 to 57). In all, 43 lower-limb segments (27 femora and 16 tibiae) were osteotomised and the deformity corrected using a monolateral external fixator. The segment was then stabilised with locked intramedullary nailing. In addition, six femora in three patients were subsequently lengthened by distraction osteogenesis. The mean follow-up was 60 months (18 to 120). The frontal alignment parameters (the mechanical axis deviation, the lateral distal femoral angle and the medial proximal tibial angle) and the sagittal alignment parameters (the posterior distal femoral angle and the posterior proximal tibial angle) improved post-operatively. The external fixator was removed either at the end of surgery or at the end of the lengthening period, allowing for early mobilisation and weight-bearing. We encountered five problems and four obstacles in the programme of treatment. The use of intramedullary nails prevented recurrence of deformity and refracture.     

Plastic repair using the demineralized matrix of flat allogeneic bone in an operation for ventral hernia

Investigations were performed in experiments on 36 dogs. Clinico-morphological results of plasty of artificial defects of the anterior abdominal wall by demineralized matrix of a flat allogeneic bone have shown good taking by tissues. In clinic the demineralized matrix of flat allogeneic bone (scapula, skull fornix) was used in ventral hernias in 36 patients. No recurrent hernias were noted in these patients within 20 months after operation.     

The effect of demineralized bone matrix gel on bone ingrowth and fixation of porous implants

The presence of demineralized bone matrix (DBM) gel did not enhance or accelerate attachment strength or bone ingrowth and resulted in a significant decrease in implant interface attachment strength at 3 weeks. Hydroxyapatite (HA) coating resulted in significant increases in interface shear strength and bone ingrowth compared with non-HA-coated porous implants at all time periods. The HA-coated implants achieved greater attachment strength and bone ingrowth at earlier time periods and maintained greater attachment strength at long-term periods. The results of this study indicate that in the presence of a good bone-implant interference fit, there is no beneficial effect in applying DBM gel to a porous-coated or HA-coated porous implant surface. The small amount that can be applied and the degree of osteoinductivity of DBM seem to preclude it from having a significant biologic effect.     

Use of demineralized bone sawdust in the treatment of spinal injuries

The experimental investigation for the purpose of studying the possibility of intervertebral osseous adhesion formation when demineralized osseous sawdust is introduced in the intervertebral disk in case of penetrating fractures of bodies of vertebra has been carried out. In 70% of cases the osseous adhesion is formed at the level of disks which demineralized osseous sawdust was introduced to (adhesion was formed, mainly, as perifocal osseous stratifications). Osseous adhesion, in case of introduction of lekozim to the damaged disk, was noted in 20% of cases (1 animal). Osteogenesis in disks was absent in all observations in the control group. When used in clinics in 12 patients with injuries of vertebral column in 63.6% of them perivertebral osseous connection has been formed during 8-12 months.     

Cartilage resurfacing of the rabbit knee. The use of an allogeneic demineralized bone matrix-autogeneic perichondrium composite implant

A full-thickness articular-cartilage defect was created in the medial femoral condyles of 32 adult rabbits. The defects were filled with demineralized bone or a composite of demineralized bone and perichondrium. Results of cartilage repair were assessed after 12 weeks of implantation. We conclude that demineralized bone matrix used as a subchondral matrix in a cartilage repair model 1) stimulates and induces subchondral bone ingrowth, 2) provides a surface on which cartilage repair can proceed, and 3) can be utilized as a platform on which perichondrium can be fixed to provide a cellular source for cartilage repair. Repair tissue that developed from perichondrium was thicker, more closely resembled normal articular cartilage, and was of a less fibrous nature than the repair tissue that developed de novo on the demineralized bone matrix.     

Use of demineralized bone matrix in ankle/hindfoot fusion

Sixty-three patients who underwent complex ankle or hindfoot fusion had demineralized bone matrix placed in their fusion site to stimulate fusion. Thirty-seven patients had Grafton putty, a demineralized bone matrix product, and 26 patients had Orthoblast, a demineralized bone matrix mixed with crushed cancellous allograft bone placed to stimulate their fusion site. All patients were followed clinically and radiographically to fusion or nonunion. Of the 37 patients who had Grafton putty placed to stimulate ankle or hindfoot fusion, five (14%) developed a nonunion. Of the 26 patients who had Orthoblast placed to stimulate fusion, two (8%) developed a nonunion. These differences were not statistically significant. Nonunion rates of approximately 10% continue to be reported for ankle and hindfoot fusion procedures. In an attempt to minimize this complication, various bone graft substitutes have been used. We found no difference in efficacy of the two demineralized bone matrix compounds, and were not able to demonstrate a superior union rate compared to historical controls.     

Mechanical modulation of growth for the correction of vertebral wedge deformities.

This study tested the following hypotheses: (a) a vertebral wedge deformity created by chronic static asymmetrical loading will be corrected by reversal of the load asymmetry; (b) a vertebral wedge deformity created by chronic static asymmetrical loading will remain if the load is simply removed; and (c) vertebral longitudinal growth rates, altered by chronic static loading, will return to normal after removal of the load. An external fixator was used to impose an angular deformity (Cobb angle of 30 degrees) and an axial compression force (60% body weight) on the ninth caudal (apical) vertebra in two groups of 12 5-week-old Sprague-Dawley rats. This asymmetrical loading was applied to all rats for 4 weeks to create an initial wedge deformity in the apical vertebra. The rats from group I (load reversal) then underwent 1 week of distraction loading followed by 4 weeks of asymmetrical compressive loading with the imposed 30 degree Cobb angle reversed. The rats from group II (load removal) had the apparatus removed and were followed for 5 weeks with no external loading. Weekly radiographs were obtained and serial fluorochrome labels were administered to follow vertebral wedging. After the initial 4-week loading period, the combined average wedge deformity that developed in the apical vertebra of the animals in both groups was 10.7 +/- 4.4 degrees. The group that underwent load reversal showed significant correction of the deformity with the wedging of the apical vertebra decreasing to, on average, 0.1 +/- 1.4 degrees during the 4 weeks of load reversal. Wedging of the apical vertebra in the group that underwent load removal significantly decreased to 7.3 +/- 3.9 degrees during the first week after removal of the load, but no significant changes in wedging occurred after that week. This indicated a return to a normal growth pattern following the removal of the asymmetrically applied loading. The longitudinal growth rate of the apical vertebra also returned to normal following removal of the load. Vertebrae maintained under a load of 60% body weight grew at a rate that was 59.4 +/- 17.0% lower than that of the control vertebrae, whereas after vertebrae were unloaded their growth averaged 102.4 +/- 31.8%. These findings show that a vertebral wedge deformity can be corrected by reversing the load used to create it and that vertebral growth is not permanently affected by applied loading.     

Use of demineralized bone matrix and plate for sternal stabilization after traumatic dislocation

Traumatic sternal segments dislocation is a rare pathology that is on the increase because of road accidents. Ideal treatment is controversial as it is a benign non-life-threatening lesion. The few cases reported in the literature do not shed light on any preferred procedure. In the present study, three patients were treated by surgical steel monofilament and eight by titanium screws and plates and demineralized bone matrix. The reduced hospitalization, rapid functional recovery, and excellent aesthetic results of the titanium patients make use of the surgical approach inevitable.