Demineralized Bone Matrix Allograft Research Articles

Does use of Allograft Affect Union Rates in Minimally Invasive Hallux Valgus Surgery?

Category: Bunion; Basic Sciences/Biologics Introduction/Purpose: Hallux valgus is a common foot deformity that can cause significant discomfort. Surgical correction of hallux valgus can be achieved through various techniques with minimally invasive surgery (MIS) gaining popularity amongst surgeons. The use of allograft in traditional open approaches has been proposed to improve the outcomes of hallux valgus repair by expediting time to union. We performed a retrospective analysis of patients undergoing MIS hallux valgus correction with and without the allograft at time of surgery. The primary aim of our study was to determine if use of allograft in hallux valgus MIS correction led to different time to union as well as rate of unions. Methods: A retrospective analysis was conducted to compare outcomes of patients who underwent hallux valgus correction with or without allograft. Patients included in the analysis underwent primary hallux valgus correction using third generation minimally invasive techniques and had postoperative weightbearing x-rays. Exclusion criteria included revision surgery, open surgeries, and loss-to-follow up. All surgeries were performed by three fellowship trained Foot and Ankle Orthopaedic surgeons at a single center from September 2019 to December 2022. All patients had similar post operative protocols. The allograft group received 2- 5 cc’s of a demineralized bone matrix (DBM) gel. Radiographs were evaluated by two independent orthopedic surgeons who were blinded to the patient's group allocation. The primary outcome of this study was time to radiographic union and rate of union. The data was analyzed using the independent t- test for continuous variables and the Fisher Exact test for categorical variables. Results: Seventy-two patients (77 feet) met inclusion criteria: allograft group (n=25) and a control group (n=52). Demographics between both groups were similar; the overall demographics can be found in Table 1. In our study, all 77 feet obtained complete union and no malunions or non-unions were observed in either group. The average time to complete union for the allograft group was 3.52 months (± 1.58) and the control group was 4.36 months (± 2.20); union times between groups did not reach statistical significance (p = 0.09) but did demonstrate a trend towards significance (Figure 1.) Maintenance of surgical correction was observed in all patients. Conclusion: While there was no statistically significant difference in union time and/or rates between the allograft group and control group, the allograft recipients had a reduction in the average time to union post MIS hallux valgus correction. No differences were observed with regards to radiographic recurrence nor complications between the two groups. This study suggests that demineralized bone matrix allograft may potentially decrease time to union but further studies are needed to confirm this.

Does the Addition of Bone Marrow Aspirate Concentrate from the Pelvis Improve Fusion Rates of Hindfoot and Ankle Arthrodesis?

Category: Ankle Arthritis; Ankle; Hindfoot Introduction/Purpose: Ankle and hindfoot arthrodesis are common interventions for degenerative and inflammatory foot and ankle conditions. These include, but are not limited to osteoarthritis, inflammatory arthritis, deformity, and instability. While we know the addition of bone graft is critical for successful union, we do not fully understand how graft selection affects union rates. Demineralized bone matrix (DBM) is commonly chosen due to its ease of availability and osteoconductive and osteoinductive properties. In our study, we aim to determine if adding BMAc, and thus osteogenic properties, to a DBM allograft improves union rates following ankle and hindfoot arthrodesis. Methods: After receiving IRB approval from our institution, we collected the records of patients who underwent arthrodesis of the hindfoot (subtalar, calcaneocuboid, talonavicular) or ankle during a 10-year time period. Patients were then divided into two groups: arthrodesis performed with the use of DBM and arthrodesis performed with DMB-BMAc. Cases using other graft options such as bulk allograft, autograft, or bone morphogenic protein (BMP) were excluded. Fusion was determined by standard radiographic and clinical criteria and CT scans were utilized in cases which fusion could not be determined. Patients were followed for a minimum of 6 months. If fusion was not complete at that time clinical and radiographic exams were performed at the 9- and 12-month period. Patients were analyzed for sucussesful arthrodesis. Complications and revisions were recorded and analyzed. Results: A total of 124 patients who met the inclusion criteria were identified. In 49 patients only DBM was utilized, and 75 patients BMC was added to the DBM. At 12 months post operatively the group utilizing only DBM had a union rate of 90% while the union rate of the BMAc/DBM had a union rate of 88% (p=0.985) There was no difference in the rate of complications between the two groups and the groups were matched in terms of age, smoking status, DM, sex and BMI. Additionally, in our cohort there was a trend toward increased non-union and complication rate in smokers, although this did not reach statistical significance. Conclusion: Ankle and hindfoot arthrodesis are a reliable treatment option for patients with specific foot and ankle pathology. Our study reports a fusion rate in line with previous studies. The addition of BMAc from the pelvis, attempting to improve the biology of the fusion site, to DBM does not seem to affect fusion rates.

Ridge Augmentation Comparing a Cancellous Block Allograft to an Osteoinductive Demineralized Bone Matrix Allograft: A Randomized, Controlled, Blinded Clinical Trial.

Twenty-six patients with a horizontal ridge defect were entered into this 4-month randomized, controlled, blinded clinical trial to compare a cancellous block allograft to a demineralized bone matrix (DBM) allograft for ridge augmentation. Six patients were excluded from the study, leaving 20 for data interpretation. Both groups had a xenograft overlay and a collagen membrane. For the Block group there was a significant gain of 4.8 ± 1.9 mm (P = .00002; 95% confidence interval [CI]: 3.49 to 6.21), while the DBM group gained 4.6 ± 2.4 mm (P = .0002; 95% CI: 2.88 to 6.36). Vertical change was minimal for both groups (P > .05). The Block group had a mean of 40% vital bone while the DBM group had 35%.

Clinical Evaluation of Demineralized Bone Matrix Allograft in Femur Fracture in Dogs

Eight clinical cases of dogs having femur fracture, were divided into two groups, A and B with four dogs (n=4) in each group. Group A animals were treated with intramedullary pinning (IMP) alone and group B were treated using IMP alongwith demineralized bone matrix (DBM) implantation at the fracture site. The efficacy of healing was evaluated on the basis of clinical evaluation, haemato-biochemical and radiographic parameters on the day of admission (day 0), followed by 7th, 15th, 30th, 45th and 60th post-operative days. The weight bearing was observed to be better in dogs of group A. Swelling was completely absent after 15th post-operative day in dogs of both the groups. The mean values of Hb, PCV, TLC and DLC showed a non-significant variation on subsequent post-operative days in both the groups. There was a significant increase in serum calcium up to 30th post-operative day and thereafter, followed a decreasing trend. The serum alkaline phosphatase values showed non-significant variation in group A while in group B animals significant increase observed on 15th, 30th and 45th post-operative day. Radiographically, the dogs of group B showed better radiographic union of fracture evidenced by early disappearance of fracture line than those of group A.

Missed posterior shoulder dislocation and McLaughlin lesion after an electrocution accident

Posterior shoulder dislocation is a rare event that may occur after a direct trauma, an epileptic seizure, electric shock or electroconvulsive therapy. In more than 50% of the cases, posterior dislocations are missed on initial evaluation and often misdiagnosed as frozen shoulders with unfortunate consequences. We present the case of a missed posterior subluxation and reverse Hill Sachs lesion (McLaughlin lesion) in a 40-year-old woman caused by anelectric shock of 240V. The patient underwent surgery in our institute two weeks after the injury. The humeral head was reduced and the reverse Hill Sachs lesion was filled by demineralized bone matrix allograft with osteoinductive factors. Tendons were repaired and a temporaneous artrodesis was performed. At the final follow up of 12 months, we obtained a Costant Score of 93 and the patient returned to her previous daily activities.

Failure of bone regeneration after demineralized bone matrix allograft in human maxillary sinus floor elevation

ABSTRACT Background and aims: There are a number of different commercially available demineralized bone matrix (DBM) products with significant differences between products with regard to the osteoinductive effect in bone defects. We aimed to evaluate the cellular response for the osteoinductive effect of the DBM graft materials by immunohistochemistry. Methods: Among five cases of sinus mucosa biopsy from the implant placement into the sinus floor elevation using DBM allograft, one case showed an intact sinus mucosa containing DBM inserted 4 months ago, while the others were severely infected and unable to be compared with each other for the osteoinductive effect of DBM. Immunohistochemistry investigations were undertaken. Results: The multinucleated giant cells were strongly positive for RANKL, cathepsin K, and HSP‐90, and consistently positive for lysozyme, TNF‐α, CD31, CD68, MMP‐2, and MMP‐9. The stromal cells were strongly positive for osteonectin and osteocalcin, but weak for BMP‐2, BMP‐4, RUNX2, TGF‐β1, CTGF, and TGase‐2. Conclusions: For sinus floor elevation the autogenic bone graft or osteogenic stem cell replacement is necessary, whereas DBM allograft only being insufficient.

Histological and Radiographic Evaluations of Demineralized Bone Matrix and Coralline Hydroxyapatite in the Rabbit Tibia

Complex fractures resulting in bone loss or impaired fracture healing remain problematic in trauma and orthopedic surgeries. Many bone graft substitutes have been developed and are commercially available. These products differ in their osteoconductive and osteoinductive properties. Differential enhancement of these properties may optimize the performance of these products for various orthopedic and craniofacial applications. The use of bone graft substitutes offers the ability to lessen the possible morbidity of the harvest site in autografts. The objective of the present study was to compare the ability of two bone graft substitutes, BioSet RT, an allograft demineralized bone matrix formulation, and ProOsteon 500R, a coralline hydroxyapatite, in a rabbit critical tibial defect model. BioSet RT and ProOsteon 500R were implanted into a unicortical proximal metaphyseal tibial defect and evaluated for new bone formation. Samples were analyzed radiographically and histologically at 1 day, 6 weeks, 12 weeks, and 24 weeks post surgery. Both materials were biocompatible and demonstrated significant bone growth and remodeling. At 12 weeks, the BioSet RT implanted sites demonstrated significantly more defect closure and bone remodeling as determined by radiographic analyses with 10 out of 14 defects being completely healed versus 1 out of 14 being completely healed in the ProOsteon 500R implanted sites. At 24 weeks, both materials demonstrated complete closure of the defect as determined histologically. There were no statistical differences in radiographic scores between the two implanted materials. However, there was an observable trend that the BioSet RT material generated higher histological and radiographic scores, although not statistically significant. This study provides evidence that both BioSet RT and ProOsteon 500R are biocompatible and able to induce new bone formation as measured in this rabbit model. In addition, this in vivo study demonstrates the ability of BioSet RT to induce new bone formation in a shorter timeframe than ProOsteon 500R.

Treatment of Symptomatic Greater Trochanteric Fracture After Total Hip Arthroplasty

Isolated greater trochanter fractures after total hip arthroplasty are associated with major comorbidities such as debilitating weakness, pain, and dislocation. No definitive standard of care has been established for these fracture. However, it is well known that reestablishing osseous union in these patients is strongly associated with return of functional status. We report a case of an elderly patient with multiple hip revision surgeries now presenting with unilateral greater trochanter fracture. Treatment incorporated the use of a trochanteric claw plate, cerclage wiring, and adjuvant demineralized bone matrix allograft to achieve successful osseous union. This is the first reported use of adjuvant demineralized bone matrix for fixing these fractures.

Poster 135: Alveolar Ridge Augmentation Utilizing Demineralized Bone Matrix Allograft

Freeze dried demineralized bone products have been used for augmentation of alveolar ridge defects for years with varying success. Defect location and barrier membrane material have been identified as variables which affect the success of a particular graft. The aim of this study was to evaluate the efficacy of a demineralized bone matrix allograft to augment various types of ridge defects for the placement of endosseous dental implants. Four hundred forty-nine ridge augmentations in 364 patients using demineralized bone matrix block impregnated with cortical chips, demineralized bone matrix paste or a combination of both were evaluated. Buccal and crestal ridge augmentations were performed in areas of insufficient alveolar bone height and width to allow an acceptable restorative position and primary stability of an endosseous dental implant. The augmentations also utilized a combination of barrier materials. The extent of buccolingual regeneration was deemed a “success” if implants of at least 4.1 mm diameter could be placed into the proposed site with at least 1 mm of facial/buccal bone thickness. Placement of a 4.1 mm diameter implant that required “patch” augmentation of a cervical dehiscence to achieve a buccal or facial bone thickness of at least 1mm was deemed a “partial success”. A “failure” occurred when a 4.1 mm diameter implant could not be placed in a desired location due to lack of osseous coverage of at least 1 mm over the implant surface. Apico-occlusal regeneration was a “success” if at least 8 mm of ridge height was achieved to provide long term support of the planned prosthesis. n/a Implants were successfully placed in 379 of 449 sites (84.4%). An additional 49 of 449 sites (10.9%) required patch grafting. Overall, 428 of 449 sites (95.3%) had implants placed with acceptable stability. This means 21/449 (4.7%) of the graft sites required additional grafting procedures prior to implant placement. A marked difference in success/partial success rate was also noted with the use of a barrier membrane (96.9%) versus no membrane (90.8%). The results of this study would suggest demineralized bone matrix is an effective material to augment alveolar bone height and width, especially in conjunction with a barrier membrane.

Percutaneous treatment of long bone nonunions: the use of autologous bone marrow and allograft bone matrix.

Sixty-six patients with 69 "stiff" nonunions (no gross motion) of long bones were entered into a prospective study. The only therapeutic intervention was the percutaneous administration of a mixture of autologous bone marrow and allograft demineralized bone matrix on an outpatient basis. Sixty-one of the percutaneous treatments (88%) resulted in union at an average of 8.1 months (range: 2 months to 3 years). This method of treating nonunions is as successful as standard iliac crest autologous bone grafting and offers the distinct advantages of decreased morbidity, reduced costs, and shorter hospital stay.

The effect of bone graft extenders to enhance the performance of iliac crest bone grafts in instrumented lumbar spine fusion.

Allograft bone extenders are commonly used in spinal surgery to increase the available graft volume, thereby promoting and achieving a solid fusion mass. We report a single surgeon's use and early results of autologous bone graft and allograft demineralized bone matrix in 65 patients undergoing lumbar spinal fusion. Of the patients included in this study, 59 (91%) patients underwent surgical intervention for lumbar spinal stenosis, three (5%) patients had lumbar spondylolisthesis, two (3%) patients had stenosis, and one (1%) patient had bilateral spondylolysis. Forty-three (64%) women and 22 (36%) men were included in the study. The average patient age was 56 years (20-85 years, SD= +/- 16). Independent radiographic evaluation was performed. Each subsequent radiographic follow-up revealed increased improvement in average Lenke score and was statistically significant between the early (1 month) and recent (12 month) follow-ups. There were statistically significant changes in Lenke score between 1 month and 3 months follow-up (P<.01), between 3 months and 6 months follow-up (P<.001), and between 6 months and 12 months follow-up (P<.01). The gradual and constant increment of improvement in radiographic measurements in this preliminary series may indicate a positive effect of the use of bone graft extenders that may decrease the required amount of autologous bone graft. Bone graft extenders also may minimize the risks and complications associated with the harvesting procedure.

The effect of allomatrix injectable putty on the outcome of long bone applications.

Long bone defects due to nonunion or surgical excision of benign bone tumors result in areas that require rapid regeneration of local bone. This clinical and radiographic article details the results of a commercially prepared allograft demineralized bone matrix in patients with long bone voids or gaps. Of the 76 patients included for study, 41 (54%) patients were undergoing surgical intervention for removal of benign tumors or space-occupying lesions and 35 (46%) patients had long bone nonunions. AlloMatrix Injectable Putty (Wright Medical Technology, Inc, Arlington, Tenn) was used alone in 74 (97%) patients and in combination with bone marrow aspirate in two (3%) patients with tibial nonunion. Adjunctive strut allografts were used in three patients with humeral nonunion. The average time to follow-up for the combined population was 7 months (nonunion group 6 months; benign tumor group 7 months). At the most recent follow-up, radiographic evidence of the average percent of bone healing was 85.1% for the nonunion patient group and 93% for the benign tumor patient group. From this study, AlloMatrix Injectable Putty used as a bone void filler in long bone nonunions and benign tumors shows results equal to those historically reported for autograft and other materials.

Comparison of human bone marrow stromal cells seeded on calcium-deficient hydroxyapatite, β-tricalcium phosphate and demineralized bone matrix

The aim of this study was to compare three resorbable biomaterials regarding seeding efficacy with human bone marrow stromal cells (BMSCs), cell penetration into the matrix, cell proliferation and osteogenic differentiation. Calcium-deficient hydroxyapatite (CDHA), β-tricalcium phosphate ( β-TCP), and demineralized bone matrix (DBM) were seeded with human BMSCs and kept in human serum and osteogenic supplements for 3 weeks. Morphologic and biochemical evaluations were performed on day 1, 7, 14 and 21. The allograft DBM and CDHA exhibited both an excellent seeding efficacy while the performance of β-TCP was lower when compared. The total protein content and the values for specific alkaline phosphatase (ALP) increased on all matrices and no significant difference was found for these two markers. BMSCs in monolayer had a significant increase of protein, but not of ALP. Osteocalcin (OC) values increased significantly higher for BMSC in cultures on DBM when compared to CDHA and β-TCP. The OC levels decreased significantly in the BMSC monolayer culture. BMSCs were found inconsistently within the synthetic materials, whereas in DBM they were found more homogeneously distributed throughout the matrix. All three matrices promoted BMSC proliferation and differentiation to osteogenic cells. DBM allografts seem to be more favorable with respect to cell ingrowth tested by histology, and osteogenic differentiation ascertained by an increase of OC. CDHA with its high specific surface area showed more favorable properties than β-TCP regarding reproducibility of the seeding efficacy.

Applications of calcium phosphate-based cancellous bone void fillers in trauma surgery.

For more than a century, fracture repair has been augmented with autogenous cancellous bone grafting, which supplies 3 requisite properties: growth factors for osteoinduction, progenitor stem cells for osteogenesis, and scaffolding for osteoconduction. However, disadvantages to using autogenous bone include procurement morbidity, longer operative time, and limited availability. Allograft is more readily available but does not supply osteoinductive or osteogenic properties. Better alternatives for bone grafting currently include autologous bone marrow, ceramics, allograft demineralized bone matrix, and regulatory growth factors; however, none of these fulfills all 3 requisite properties. Replacement or augmentation of autograft with a calcium phosphate-based composite graft, which combines the best elements of each component into a single engineered graft, is discussed.

Comparison Between Allograft Plus Demineralized Bone Matrix Versus Autograft in Anterior Cervical Fusion|A Prospective Multicenter Study

This study analyzed the fusion results of an allograft-demineralized bone matrix composite versus autograft in a prospective series of patients undergoing surgery for cervical disc disease. To determine the fusion rates of allograft-demineralized bone matrix composite in anterior cervical fusion as compared with the gold standard autograft. For the anterior cervical fusion, the use of freeze-dried allograft is well documented in the literature, citing its effectiveness and inferior fusion rates. The use of demineralized bone matrix in conjunction with freeze-dried allograft in anterior cervical fusion has not been reported. This study was done in a prospective fashion in two medical centers. One group received autograft from the anterior iliac crest, whereas others received freeze-dried allograft augmented with demineralized bone matrix (Grafton, Osteotech, Inc., Shrewsbury, New Jersey). For the autograft group, the standard Smith-Robinson grafting technique was used. For the allograft composite group, demineralized bone matrix was pasted onto the freeze-dried allograft and into the disc space before graft insertion. The autograft group consisted of 38 patients with age ranging 26-71 years (mean, 46.1 years) and follow-up periods of 12-33 months (mean, 18.4 months). There were 19 one-level, 17 two-level, and two three-level fusions. Similarly, the allograft group consisted of 39 patients with age ranging 28-80 years (mean, 48.0 years) with follow-up period of 12-31 months (mean, 17.5 months). There were 19 one-level, 16 two-level, and four three-level fusions. Clinical and radiographic follow-up evaluations were completed at 3-month intervals. Radiographs taken 12 months after surgery were analyzed blindly. Pseudarthrosis developed in 46.2% of patients (33.3% of levels) in the allograft-demineralized bone matrix group compared with 26.3% (22% of levels) in the autograft group (P = 0.11 for patients, P = 0.23 for levels). For patients undergoing two-level fusions, 37.5% of allograft-demineralized bone matrix failed compared with 23.5% of autografts. For single-level fusions, 47.4% of allograft patients developed a pseudarthrosis compared with 26.3% in the autograft group. Graft collapse of > or = 3 mm was noted in 11% of the autograft group versus 19% in the allograft-demineralized bone matrix group (P = 0.32). Graft collapse of > or = 2 mm occurred in 24.4% of autograft patients compared with 39.7% of the allograft-demineralized bone matrix group (P = 0.09). Smokers had an increased rate of pseudarthrosis (47.1%) compared with nonsmokers (27.9%, P = 0.13). The study revealed that the allograft-demineralized bone matrix construct gives a higher rate of graft collapse and pseudarthrosis when compared with autograft in a prospective series, although the differences were not statistically significant. The pseudarthrosis rate in the series may be high because of the large percentage of smokers and radiographic evaluation techniques. For the purpose of solid radiographic fusion, the use of autograft is recommended in anterior cervical surgery until other acceptable osteoinductive materials are developed.

The Healing of Grafts Combining Freeze-Dried and Demineralized Allogeneic Bone in Rabbits

The adjunctive role of demineralized bone matrix (DBM) in enhancing the incorporation of segmental freeze dried (FD)-allogeneic bone grafts has been studied in the rabbit ulna and fibula. The studies compared the healing patterns of fresh segmental autografts, FD-allografts, DBM-allografts, and FD-allografts supplemented at the graft-host junctions with FD- or DBM-allografts as particulates (ulna) or as segmental struts (fibula). The outcome was evaluated at five and ten weeks by a radiologic score, by biomechanical properties (breaking strength, energy to failure, stiffness), and histology. The ulnar autografts healed most rapidly (ten weeks = 100%), followed by DBM allografts (60%). By all criteria, FD-allografts were poorly incorporated (20-40%), and the process was not improved by supplements of FD- or DBM-particulate/strut bone. Histologically, the DBM component of composite fibular strut grafts was osteoinductive and united with host tissues within 35 days. The contiguous FD-allograft struts were not incorporated, showing fibrocartilaginous nonunions and resorptive foci. While the addition of DBM does not protect FD-allograft integrity in the rabbit, segmental mineralized FD-allografts could provide mechanical support for some intervals until, in such composite grafts, osteoinductive processes produced biomechanically competent new bone.

The matrix of endochondral bone differs from the matrix of intramembranous bone

Osseous tissue develops via two distinctly different processes: endochondral (EC) ossification and intramembranous (IM) ossification. The present study tests the hypothesis that each type of osseous tissue contains unique inducing factors for the promotion of cartilage and bone development. Previous work suggests that subcutaneous implants of demineralized EC and IM bone matrices both induce endochondral ossification. Thus, it concludes that the bone growth promotion properties of the respective matrices are very similar. As it was unclear to us why EC and IM bone powders should possess identical osteoinductive properties, we attempted to reproduce these results. We implanted EC (femoral) demineralized bone matrix (DBM), IM (frontal) DBM, or a mixture of the two into the ventral thoracic subcutaneous tissue of 12 to 15-week-old male Sprague Dawley rats. Morphological and radiolabeling techniques in this study demonstrated that implants of EC bone matrix induce bone formation via EC ossification in contrast to implants of IM bone matrix which do not induce EC ossification. Our findings suggest that the matrix of EC bone differs qualitatively from the matrix of IM bone due to their respective abilities to induce cartilage and/or bone formation. These observations differ from those previously reported possibly because our IM DBM preparations were not contaminated with tissues of endochondral origin. In current clinical practice, EC DBM allografts are often used to induce new bone formation in defects involving both IM and EC bone. We conclude that there may be clinical settings in which it would be more appropriate to replace bone originally formed via IM ossification with IM DBM rather than EC DBM.

Posterior Cervical Spine Stabilization Under Local Anesthesia

A technique is described for posterior cervical stabilization with spinous process wiring and fusion performed with the patient under local anesthesia and using corticocancellous demineralized bone matrix allograft. In patients with unstable cervical spines, posterior stabilization and fusion with local anesthesia allowed patient interaction with the surgeon during crucial parts of the operation. The technique was well tolerated and no untoward complications occurred. The technique has not been described for the neurologically intact patient with cervical spine trauma. The purpose of this report is to document the facility and advantages of this technique over traditional general anesthesia with autograft use. Nineteen patients were treated surgically at the author's institution. Local anesthesia was used in 12, and general anesthesia was used in 7. Allograft was used in 12 and autologous iliac crest graft was used in 7 patients. The indications for surgery were instability or neurologic deficit. Blood loss and operative times were favorable when compared with general anesthesia and autograft. The fusion extended by one level in 6 of 19 patients. One patient had preoperative neurologic deficit. All 19 follow-up patients were Frankel grade E. There is no need for endotracheal intubation, the patient serves as his or her own spinal cord monitor, and the surgeon is able to be aware immediately of any threat to neurological function. Demineralized bone matrix allograft has been shown to effectively induce osteogenesis by osteoinduction as well as osteoconduction. Its use eliminates the need for autograft harvesting and permits the use of local anesthesia alone for cervical spine posterior stabilization. The more neurologically intact the patient, the more this technique is indicated.(ABSTRACT TRUNCATED AT 250 WORDS)