Cancellous Bone Allograft Research Articles

In Vivo Evaluation of Demineralized Bone Matrix with Cancellous Bone Putty Formed Using Hydroxyethyl Cellulose as an Allograft Material in a Canine Tibial Defect Model.

Demineralized bone matrix (DBM) is a widely used allograft material for bone repair, but its handling properties and retention at defect sites can be challenging. Hydroxyethyl cellulose (HEC) has shown promise as a biocompatible carrier for bone graft materials. This study aimed to evaluate the efficacy of DBM combined with cancellous bone putty formed using HEC as an allograft material for bone regeneration in a canine tibial defect model. Experiments were conducted using dogs with proximal tibial defects. Four groups were compared: empty (control group), DBM + HEC (DH), DBM + cancellous bone + HEC (DCH), and DBM + cancellous bone + calcium phosphate + HEC (DCCH). Radiographic, micro-computed tomography (CT), and histomorphometric evaluations were performed 4 and 8 weeks postoperatively to assess bone regeneration. The Empty group consistently exhibited the lowest levels of bone regeneration throughout the study period, indicating that DBM and cancellous bone with HEC significantly enhanced bone regeneration. At week 4, the DCCH group showed the fastest bone regeneration on radiography and micro-computed tomography. By week 8, the DCH group showed the highest area ratio of new bone among all experimental areas, followed by the DH and DCCH groups. This study demonstrated that HEC significantly enhances the handling, mechanical properties, and osteogenic potential of DBM and cancellous bone grafts, making it a promising carrier for clinical applications in canine allograft models. When mixed with allograft cancellous bone, which has high porosity and mechanical strength, it becomes a promising material offering a more effective and reliable option for bone repair and regeneration.

Opening-Wedge High Tibial Osteotomy with a Cancellous Strut Bone Allograft Is Inadequate for Achieving Satisfactory and Lasting Correction in Neglected Infantile Tibia Vara: Results from a Cohort of 29 Patients.

Background: Infantile tibia vara (ITV) is a rare proximal tibia deformity in infancy, leading to progressive knee varus. High tibial osteotomy is commonly practiced but has high recurrence rates. This study analyzed factors affecting treatment failure and recurrence in children undergoing opening-wedge high tibial osteotomy (OWHTO) for ITV. Methods: We retrospectively studied children with ITV who had OWHTO with a press-fit cancellous bone allograft between 2000 and 2020, with ≥2-year follow-up. Outcomes included recurrence (knee varus with tibiofemoral angle > 10°), complications, and reintervention. Results: We analyzed 39 knees in 29 patients (mean age: 4.8 ± 1.9 years; median follow-up: 7.4 years). Recurrence occurred in 22 cases (56%). Age at surgery significantly influenced recurrence, with rates of 16% before age 5 versus 95% later (hazard ratio: 12.0, p = 0.001). Langenskiöld stage also affected recurrence (β-coefficient: 2.7, 95% C.I. 1.0-4.5, p = 0.002; pseudo-R-squared: 0.50, p = 0.001), with recurrence in all stage IV or higher cases. Conclusions: Early diagnosis and treatment before age 5, ideally with Langenskiöld stage III or lower, are crucial for stable correction with OWHTO alone. Late, high-grade ITV may require combined, acute or gradual, and/or staged correction. Further evidence is needed for optimal management.

Clinical and Biological Validation of an Allogeneous Cancellous Bone Block for Alveolar Maxillary Ridge Reconstruction: A Case Series.

This exploratory case series clinically and histologically investigated the performance of allogeneic cancellous freeze-dried bone allograft (FDBA) bone blocks (Maxgraft®) for the lateral augmentation of local alveolar defects in the posterior maxilla as part of two-staged implant therapy. Five patients receiving eight implants 5 months after block augmentation with a follow-up period of up to 3 years were documented and analyzed. Horizontal alveolar dimensions before and 5 months after block augmentation were quantified using CBCT. Radiographic marginal bone level changes were quantified at implant placement, loading, and 1 year post-placement. Graft integration and resorption were histologically qualitatively evaluated from core biopsies retrieved at implant placement. Block augmentations resulted in a pronounced horizontal median bone gain of 7.0 (5.5 to 7.8) mm. Marginal implant bone levels in block-augmented bone remained constant over the 1 year follow-up period. Block grafts appeared histologically well integrated. Histologic analysis also revealed signs of progressive resorption and new bone formation at the lateral aspects of the grafts. The results of this case series support using Maxgraft® cancellous FDBA blocks as suitable materials for the lateral augmentation of local alveolar defects.

Evaluation of Integrity of Allogeneic Bone Processed with High Hydrostatic Pressure: A Pilot Animal Study.

Processing of bone allografts with strong acids and γ-sterilization results in decreased biomechanical properties and reduction in osteogenecity and osteoconductivity. High hydrostatic pressure (HHP) treatment could be a gentle alternative to processing techniques usually applied. HHP is known to induce devitalization of cancellous bone while preserving biomechanical stability and molecules that induce cell differentiation. Here, a specific HHP protocol for devitalization of cancellous bone was applied to rabbit femoral bone. Allogeneic bone cylinders were subsequently implanted into a defect in the lateral condyles of rabbit femora and were compared to autologous bone grafts. Analysis of bone integration 4 and 12 weeks postoperatively revealed no differences between autografts and HHP-treated allografts regarding the expression of genes characteristic for bone remodeling, showing expression niveous comparable to original bone cylinder. Furthermore, biomechanical properties were evaluated 12 weeks postoperatively. Autografts and HHP-treated allografts both showed a yield strength ranging between 2 and 2.5 MPa and an average bone mass density of 250 mg/cm2. Furthermore, histological analysis of the region of interest revealed a rate of 5 to 10% BPM-2 and approximately 40% osteocalcin-positive staining, with no marked differences between allografts and autografts demonstrating comparable matrix deposition in the graft region. A suitable graft integrity was pointed out by μCT imaging in both groups, supporting the biomechanical data. In summary, the integrity of HHP-treated cancellous bone allografts showed similar results to untreated autografts. Hence, HHP treatment may represent a gentle and effective alternative to existing processing techniques for bone allografts.

Sinus floor augmentation using mineralized freeze-dried bone allograft combined with recombinant human bone morphogenetic protein-2 (rhBMP-2): A long-term retrospective study

Background/purposeThe combination of recombinant human bone morphogenetic protein-2 (rhBMP-2) with a carrier material has not been extensively studied. This study aimed to evaluate the clinical, radiological, and histomorphometric outcomes of sinus floor augmentation using a 3:7 mixture of cancellous and cortical freeze-dried bone allografts (mixed AG) combined with rhBMP-2. Materials and methodsMixed AG was used for sinus floor augmentation in a total of 21 patients with a residual alveolar bone height <5 mm. Among the total 47 sites, augmentation with and without rhBMP-2 was performed in 26 and 21 sites, respectively. Radiographic parameters were assessed using cone-beam computed tomography. After a six-month healing period, core biopsies were harvested for histomorphometric analysis. ResultsThe bone gain after healing was 13.36 ± 3.9 mm and 12.07 ± 3.8 mm in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively. The survival rate of implants in both groups was 100% during the follow-up period. The proportion of newly formed bone was 24.6 ± 10.2% and 39.7 ± 18.3% in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively (P < 0.05). Moreover, the percentage of residual graft material was 21.0 ± 12.2% and 9.6 ± 10.0% in the mixed AG alone and mixed AG with rhBMP-2 groups, respectively (P < 0.05). ConclusionMixed AG combined with rhBMP-2 could be a suitable material for sinus floor augmentation. This combination may reduce the treatment time and improve the predictability of implant placement.

Rotator Cuff Repair With Bone Grafting of Greater Tuberosity Cyst: A Technique Video

Background: Nearly 500,000 rotator cuff repairs are performed annually in the United States. Cysts within the humeral head have been reported to occur in more than half of patients diagnosed with a rotator cuff tear. They are related to age-related degeneration and rotator cuff dysfunction, and may arise from congenital abnormalities. Indications: Humeral head cysts may pose technical challenges during rotator cuff repair. Cysts located at the footprint of a planned rotator cuff repair can decrease biological healing capacity and reduce the fixation strength of suture anchors. One treatment strategy to address bone loss secondary to humeral head cysts is to incorporate cancellous allograft bone chips, which provide an osteoconductive scaffold for bone formation. Technique Description: Standard arthroscopic portals were established and during arthroscopy, the rotator cuff tear was identified, and tissue was mobilized. The cyst was debrided to healthy, bleeding bone using curettes and an arthroscopic shaver. A 2.5 mL sterile syringe was packed with crushed, cancellous allograft bone chips. The tip of the syringe was removed to allow for a wider aperture to facilitate injection of bone chips. Through an accessory, percutaneous portal just lateral to the acromion, the syringe was inserted into the cyst site, and bone graft contents were injected into the cyst. Pressure was applied to the syringe to impact the bone graft material. The bone chips were impacted with the syringe plunger. Following rotator cuff repair, the patient underwent subacromial decompression, distal clavicle excision, and open sub-pectoral biceps tenodesis with suture anchor fixation. Discussion/Conclusion: Greater tuberosity cysts can impose a technical challenge during arthroscopic rotator cuff repair. Incorporation of impacted cancellous allograft bone chips is an efficient, reproducible method to enhance healing of the RTC tendon enthesis. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Comparison of the Effects of Tissue Processing on the Physicochemical Properties of Bone Allografts.

Purpose: To address the hypothesis that the tissue processing methods of solvent dehydration and freeze-drying would differentially affect the physicochemical characteristics of four commercially available bone allografts and the adhesion and differentiation of human bone marrow-derived mesenchymal stromal cells (hBMSCs) on such substrates in vitro. Materials and Methods: The surface morphology, surface area, and elemental composition of four commercially available cancellous bone allografts were examined using SEM, Brunauer-Emmett-Teller (BET) gas adsorption, and inductively coupled plasma (ICP) analyses. SEM was also employed to compare the allograft surfaces to that of human bone exposed by in vitro osteoclastic resorption. The allografts were seeded with hBMSCs, and the number of adhered cells was assessed at 3 and 7 days. Alkaline phosphatase (ALP) activity was quantified as a measure of osteogenic differentiation after 21 days. Results: Marked differences were seen between the physicochemical characteristics of the solvent-dehydrated and freeze-dried allografts, as well as between their resulting bone microarchitectures and that of osteoclast-resorbed human bone. Increased hBMSC adhesion and differentiation were observed on the solvent-dehydrated allografts compared to freeze-dried allografts, which suggests a higher putative osteogenic potential. The latter was attributed to better preservation of the bone collagen microarchitecture integrity, which may provide not only a more complex substrate architecture, but also a more favorable microenvironment to allow nutrients and oxygen to flow to the adhered cells. Conclusion: Commercially available cancellous bone allografts significantly differ in their physicochemical characteristics, stemming from differences in tissue processing and sterilization methods undertaken by tissue banks. These differences impact the response of MSCs in vitro and may alter the biologic performance of the grafts in vivo. Therefore, it is important to consider these characteristics when choosing a bone substitute for clinical application, as the physicochemical properties of the grafts play a crucial role in their interactions with the biologic environment and subsequent incorporation into the native bone.

Increased Peri-implant Bone Formation Around Simultaneously Grafted Hydrophilic Microrough Titanium Implants: An Exploratory Human Histometric Analysis in Four Patients.

This pilot case series histologically and histometrically investigated the influence of implant surface hydrophilicity on early osseointegration and peri-implant bone formation around simultaneously grafted immediate implants. Hydrophilic test (SLAactive) or hydrophobic control (SLA) implants were immediately placed in maxillary molar extraction sites and simultaneously grafted with mineralized cancellous bone allograft (MCBA). Core biopsy samples were obtained at 3 weeks postplacement and histometrically compared for bone-to-implant contact, quantity of graft material, new bone formation, tissue reaction, and inflammatory scores. Test implants showed a more pronounced implant-bone apposition, peri-implant bone formation, and bone aggregate than control implants. Trabecular bone formation and maturation were also qualitatively advanced around test implants. These results indicate that the combination of implant surface and bone graft may affect periimplant bone formation.

Allograft-Reconstructed Iliac Bone Graft Donor Site Remodels to Viable Bone and Its Feasibility for Revision Fusion.

Bone autograft options may be limited in revision spinal fusion cases. Reconstruction of the iliac bone graft (IBG) donor site with cancellous bone allograft allows for reharvest for patients who subsequently have another fusion. This study examined viability of the reconstructed IBG (RIBG) donor sites. Secondarily, we assessed the feasibility of whether the RIBG sites could be reharvested for obtaining a successful arthrodesis for a secondary fusion. Prospectively collected data of 154 consecutive lumbar revision fusions were reviewed, of which 17 cases had their IBG donor site backfilled with allograft bone at the time of their primary fusion and subsequently had secondary surgery for a pseudarthrosis repair or fusion extension. Biopsies of the RIBG and computed tomography (CT) images were obtained at the time of secondary fusion. Histology analyzed the ratio of filled to unfilled lacunae and marrow cellularity. Histology controls were from normal iliac crest. Clinically, postoperative CT and >2-year outcomes (visual analog scale [VAS] and Oswestry Disability Index [ODI]) evaluated the feasibility of the secondary fusion surgery using RIBG. The RIBG fusion rate and outcomes were compared with clinical control revision groups that had IBG and/or bone morphogenetic protein (BMP) used for their revision fusion. CT images prior to RIBG harvest found bony healing of the original graft donor site in all except 1 case. RIBG bone marrow histology found lower cellularity vs controls, but this characteristic did not appear to compromise bone viability with filled lacunae in 83% ± 14% in the RIBG group, vs 88% ± 8% for iliac controls. After revision fusion, often combined with bone growth stimulator or BMP, repeat CT demonstrated solid spinal fusions in 16 of 17 patients, whereas control revision group fusion rates were approximately 80%. Clinical improvement was significant (VAS decrease = 3.8, ODI decrease = 16.5) and comparable with the IBG revision controls. RIBG using allograft remodels into viable predominately cancellous bone and is clinically feasible for revision fusion if IBG or BMP is unavailable. Reconstructed iliac bone graft is viable and may be used as a bone graft option.

Mentoplasty with Cancellous Bone Chip Scaffolding: An Innovative Technique for Chin Aesthetics.

The facial skeleton is foundational for facial aesthetics. The authors describe an alternative technique for cosmetic chin augmentation that does not require alloplastic implants, osseous genioplasty, or autologous bone harvesting. In this new and innovative technique for chin augmentation, tissue bank allograft cancellous bone chips serve as a scaffold for bony ingrowth. The use of bone chips allows for aesthetic contouring with small adjustments in the facial skeleton. The objective of this article is to provide further information on this novel technique and demonstrate the efficacy and safety of tissue bank allograft cancellous bone chips as an alternative graft material for cosmetic chin augmentation. Retrospective review of patients who underwent chin augmentation with cancellous bone chips from July of 2015 to March of 2019 was performed. Photographic results from several patients are included. No patients developed infections, required reoperation, or went on to have explantation of the graft material. Initial results suggest cancellous bone chips are a safe, efficacious alternative graft material for cosmetic chin augmentation. Therapeutic, IV.

Maxillary sinus floor augmentation using two different ratios of cancellous and cortical freeze-dried bone allograft mixtures: clinical and histological outcomes

Maxillary sinus floor augmentation using two different ratios of cancellous and cortical freeze-dried bone allograft mixtures: clinical and histological outcomes

Periprosthetic Joint Infection (PJI)-Results of One-Stage Revision with Antibiotic-Impregnated Cancellous Allograft Bone-A Retrospective Cohort Study.

Controversy exists regarding the optimal treatment of periprosthetic joint infection (PJI), considering control of infection, functional results as well as quality of life. Difficulties in treatment derive from the formation of biofilms within a few days after infection. Biofilms are tolerant to systemically applied antibiotics, requiring extreme concentrations for a prolonged period. Minimum biofilm eradicating concentrations (MBEC) are only feasible by the local application of antibiotics. One established approach is the use of allograft bone as a carrier, granting a sustained release of antibiotics in very high concentrations after appropriate impregnation. The purpose of this study was to determine the rate of reinfection after a one-stage revision of infected hip or knee prostheses, using antibiotic-impregnated allograft bone as the carrier and avoiding cement. Between 1 January 2004 and 31 January 2018, 87 patients with PJI, according to MSIS, underwent a one-stage revision with antibiotic-impregnated cancellous allograft bone. An amount of 17 patients had insufficient follow-ups. There were 70 remaining patients (34 male, 36 female) with a mean follow-up of 5.6 years (range 2–15.6) and with a mean age of 68.2 years (range 31.5–86.9). An amount of 38 hips and 11 knees were implanted without any cement; and 21 knees were implanted with moderate cementing at the articular surface with stems always being uncemented. Within 2 years after surgery, 6 out of 70 patients (8.6%, CI 2–15.1) showed reinfection and after more than 2 years, an additional 6 patients showed late-onset infection. Within 2 years after surgery, 11 out of 70 patients (15.7%, CI 7.2–24.2) had an implant failure for any reason (including infection) and after more than 2 years, an additional 7 patients had an implant failure. Using Kaplan-Meier analysis for all 87 patients, the estimated survival for reinfection was 93.9% (CI 88.8–99.1) at 1 year, 89.9% (CI 83.2–96.6) at 2 years and 81.5% (CI 72.1–90.9) at 5 years. The estimated survival for implant failure for any reason was 90.4% (CI 84.1–96.7) at 1 year, 80.9% (CI 72.2–89.7) at 2 years and 71.1% (CI 60.3–81.8) at 5 years. One-stage revision with antibiotic-impregnated cancellous allograft bone grants comparable results regarding infection control as with multiple stages, while shortening rehabilitation, improving quality of life for the patients and reducing costs for the health care system.

PMMA-cement anterior column reconstruction in surgical treatment of spondylodiscitis

Introduction: and research questionThis paper explains how antibiotic loaded cement can be used in surgical treatment of spondylodiscitis to reconstruct the anterior column of the spine. Material and methods35 consecutive surgical procedures performed for spondylodiscitis were collected over a 11-year period and charts were reviewed. Most infections were caused mainly by staphylococcus spp (n = 16), streptococcus spp (n = 8) and pseudomonas spp (n = 4). Most patients had long standing but unsuccessful antibiotic therapy (median 42 days). Other indications included instability, neurologic deficit, abscess, and patients were generally in very poor medical condition. ResultsAnterior debridement was followed by a partial cavity filling with surgical high viscosity PMMA cement in all cases. Cement was a high viscosity gentamycin loaded cement, that was placed in the cavity created by debridement under the direct eye control. In 25 cases, a part of the cavity was filled with freeze dried cancellous bone allograft rehydrated in rifampicin. Spine was further stabilized with an anterior plate in 15 cases, with short (+1/+1) posterior instrumentation in 5 cases, and a long (≥ +2/+2) posterior instrumentation in 11 cases. In four patients, spine was left un-instrumented. Immediate, unrestricted mobilization was always authorized after surgery. None of the patients were reoperated neither for mechanical failure nor for infection relapse. ConclusionThis report supports the idea that surgical bone cement is an efficient gap filler when used through anterior approach. For small as well as for large defects, it can help to reconstruct the anterior column and locally control the infection in combination with additional stabilization and optimal intravenous and oral antibiotic treatment.

Treatment of Critical-Size Femoral Bone Defects with Chitosan Scaffolds Produced by a Novel Process from Textile Engineering.

The purpose of this study was to investigate, in vitro and in vivo, the suitability of chitosan (CHS) scaffolds produced by the net-shape-nonwoven (NSN) technology, for use as bone graft substitutes in a critical-size femoral bone defect in rats. For in vitro investigations, scaffolds made of CHS, mineralized collagen (MCM), or human cancellous bone allograft (CBA) were seeded with human telomerase-immortalized mesenchymal stromal cells (hTERT-MSC), incubated for 14 days, and thereafter evaluated for proliferation and osteogenic differentiation. In vivo, CHS, MCM and CBA scaffolds were implanted into 5 mm critical-size femoral bone defects in rats. After 12 weeks, the volume of newly formed bone was determined by microcomputed tomography (µCT), while the degree of defect healing, as well as vascularization and the number of osteoblasts and osteoclasts, was evaluated histologically. In vitro, CHS scaffolds showed significantly higher osteogenic properties, whereas treatment with CHS, in vivo, led to a lower grade of bone-healing compared to CBA and MCM. While chitosan offers a completely new field of scaffold production by fibers, these scaffolds will have to be improved in the future, regarding mechanical stability and osteoconductivity.

Reamer-irrigator-aspirate versus bone marrow aspirate concentrate for osteoprogenitor cell retention and osteoinductive protein release on cancellous bone

Bone defects often require operative intervention with the use of bone graft. Two sources of autologous bone graft include reamer-irrigator-aspirate (RIA) and bone marrow aspirate concentrate (BMC). Osteoprogenitor cells and osteoconductive proteins have been identified in both sources. This study collected samples of these cells and proteins from a canine model and cultured them on human cancellous allograft bone blocks. Findings suggest that BMC may be preferred for indications that allow for delivery via injection, saturation of the patient's tissues, or an implanted scaffold, whereas RIA may be preferred when the biologic augment is delivered as a scaffold or graft.

Two-stage bone-and-strut technique in the treatment of septic non-unions in the upper limb.

Aim To report the results of a two-stage reconstruction of septic non-unions of the upper limb using the bone-and-strut technique with a follow-up of more than two years. Methods A total of 19 patients (12 males and seven females; age 27 to 85 years) were included in this cohort study. The evaluation endpoint was set at 24 months. Radiographic union, Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) scores, pain and return to work were assessed. All patients were treated with debridement and antibiotic therapy. At a second stage, the nonunion focus was filled with a cancellous bone allograft. Stability was provided using a locking plate and a bone strut. Results After 24 months, the QuickDASH scores improved from a median of 28 (interquartile range, 13 - 35 points), to a median of 78 (interquartile range, 70 - 89 points). Mean pain scores improved from 8.1 (range, 0.3-10) to 0.6 (range 0-2). Radiographic and clinical union was seen in all patients. The majority of patients returned to work or previous activities when retired. A new neurological deficit, recurrence of infection, or other surgery-related adverse events were not observed. Conclusion The two-stage bone-and-strut technique is a safe and effective technique in the treatment of septic non-unions of the upper limb. The union rate is high, the complication rate is acceptable and return return-to-work is high. Recurrence of infectious sequelae during a follow-up period of at least two years was not seen. The patient-reported outcomes increased significantly.

Cancellous bone allograft is comparable to fibular strut allograft for augmentation in three-or four-part proximal humeral fractures.

Bone grafts have been used for augmentation and improving stability of reduced fractures in proximal humeral fractures. The aim of this study was to analyze the clinical and radiological outcomes after the use of cancellous bone allografts (CAs) for augmentation in 3- or 4-part proximal humeral fractures, and compare with fibular strut allografts (FAs). Between November 2016 and February 2018, 55 patients, followed for at least 1 year, with 3- or 4-part proximal humeral fractures fixed with locking plates were included and grouped according to the type of allograft bone used for augmentation. In this retrospective analysis, we assessed and compared the clinical and radiological outcomes of the 2 groups, using the visual analog scale score, the Constant-Murley score (CMS), the disability of the arm, shoulder, and hand (DASH) score, the range of movement, neck-shaft angle (NSA), humeral head height (HHH), and the changes of NSA and HHH, as well as recording any complications. The repeatedly measured clinical and radiological outcomes were analyzed by linear mixed models. The differences in outcomes betweengroups at the final follow-up were compared using Student's t test. There were 28 patients in the CA group and 27 patients in the FA group with an average follow-up of 14.5 months. The mean age of all patients was 64 (36-86). Nonsignificant group effects were observed on CMS (β = -8.792, P = .216), DASH (β = 1.329, P = .094), NSA (β = 1.432, P = .752), and HHH (β = 1.660, P = .628). At the final follow-up, the patients in the CA group showed no significant differences in visual analog scale (1.8 vs. 2.2, P = .276), CMS (81.5 vs. 75.4, P = .072), and DASH (11.0 vs. 13.5, P = .235) scores compared with the FA group. There were no significant differences in the change of NSA (6 vs. 4, P = .387) or HHH (1 vs. 2, P = .261). Patients with 3- or 4-part proximal humeral fractures treated with locking plates combined with CAs have good clinical and radiographic outcomes, similar to those treated with FAs.

278. Allograft reconstructed iliac bone graft donor site remodels to viable bone and its preliminary clinical effectiveness in revision fusion

BACKGROUND CONTEXT Bone autograft options may be limited for revision spinal fusion, particularly in long deformity cases where iliac fixation or prior IBG harvest are present. Contralateral IBG may not be available or was previously harvested. Alternatives such as bone morphogenic protein, BMP, at some facilities is not available for off-label use or due to expense. Nonviable alternatives have inconsistent ability to obtain arthrodesis in revision cases. Allograft reconstructed iliac bone graft donor site has been used to decrease donor site pain; it may also be a source of bone graft in patients with multiple prior fusions who need another fusion. PURPOSE The purpose of this study was to assess the viability of bone graft donor sites reconstructed with bone allograft. A secondary purpose of this prospective cohort study was to ascertain whether the reconstructed iliac bone graft, RIBG, sites could be reharvested for successful arthrodesis in revision fusion. STUDY DESIGN/SETTING Histologic and two cohort clinical prospective study. PATIENT SAMPLE Consecutive patients who had secondary thoracolumbar spinal fusion (pseudarthrosis repair or fusion extension) using RIBG. All these patients had their initial fusion with IBG and reconstruction of the bone graft donor site with cancellous allograft. OUTCOME MEASURES Histology of RIBG biopsies (lacunae and marrow) vs controls; clinical VAS, ODI outcomes. METHODS Revision spinal fusion patients, n=16, who had their iliac bone graft donor site backfilled with allograft bone at their initial fusion and subsequently had secondary fusion surgery for a pseudarthrosis repair or fusion extension had biopsies obtained at the time of secondary fusion. Histology analyzed the RIBG biopsies for viability and was compared to controls. One-year postop CT scans and 2+ yr outcomes measures (LBP VAS & ODI) evaluated the clinical success of the secondary fusion surgery using RIBG and compared to revision fusion controls using contralateral IBG. RESULTS Histology found filled lacunae average 83%, SD 14%, and the bone marrow was hypocellular in 2/3 of cases. Control patients had average 87%, SD; 8% and no hypocellularity. CT scans of the lumbar fusions utilizing RIBG, often combined with bone growth stimulator or bone morphogenic protein (BMP), demonstrated solid fusions in 15 of 16 patients. CT scan fusion rates of the IBG or BMP control cohorts were approximately 80%. Clinical improvement was significant (3.8 VAS decrease, p CONCLUSIONS RIBG using cancellous bone allograft remodels into viable bone autograft. This study is the first to report the histological viability of RIBG site and assess the feasibility of its use in revision fusion. RIBG may be useful in secondary fusion procedures if IBG or BMP are of limited availability. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Acetabular reconstruction using a composite layer of impacted cancellous allograft bone and cement: minimum 5-year follow-up study.

Revision total hip arthroplasty (rTHA) is often complex and has a less reliable outcome than primary total hip arthroplasty. Acetabular reconstruction remains a challenge because of the variable amount of bone loss. This study describes and evaluates a novel technique of acetabular reconstruction using composite bone grafting. Between June 2005 and January 2012, 108 consecutive patients underwent revision hip arthroplasty in which the acetabular component was revised using composite bone grafting. Of these, 24 were lost to follow-up leaving 84 in the study with a minimum 5-year follow-up. There were 54 women and 30 men with a mean age of 70.1 (31-91) years. All patients were assessed clinically and radiologically after a minimum of 5 years. The primary outcome measures were rate of re-revision, patient-reported outcomes and radiological evidence of loosening. The mean follow-up after revision surgery was 6.9 years (5-10). At operation, 60 patients had an acetabular defect of AAOS stage 3 or more. There was no evidence of loosening in 69 revision acetabular components; 12 showed evidence of non-progressive loosening and 3 patients underwent a re-revision procedure (2 for infection, 1 recurrent dislocation).The mean postoperative Hip Disability and Osteoarthritis Outcome Score (HOOS) was 89.11/100 (95% CI, 87.8-90.5). Scores were significantly improved in patients with a more extensive preoperative defect (p = 0.006). The overall patient satisfaction rate at final follow-up was very high. Composite impaction grafting using a layered cement and bone graft technique can give satisfactory clinical and radiological outcomes in the medium- to long-term.

Transforaminal endoscopic decompression and uninstrumented allograft lumbar interbody fusion: A feasibility study in patients with end-stage vacuum degenerative disc disease

ObjectiveThe authors investigated the feasibility of a transforaminal endoscopic decompression and un-instrumented lumbar interbody fusion procedures with cancellous bone allograft in patients painful with end-stage degenerative vacuum disc disease. Patients & methodsTwenty-nine patients who underwent endoscopic transforaminal foraminal and lateral recess decompression and direct intraoperative endoscopic visualization of a painful, hollow collapsed, rigid intervertebral disc space were grafted with cancellous allograft chips. In addition to the radiographic assessment of fusion, patients were followed for a minimum of 2 years postoperatively, and clinical outcomes were evaluated with VAS, ODI, and modified MacNab criteria. ResultsAt the final follow, mean VAS and ODI scores reduced from 7.34 ± 1.63 and 50.03 ± 10.64 preoperatively to 1.62 ± 1.741 and 6.69 ± 4.294 postoperatively (p < 0.0001). Excellent and Good clinical outcomes, according to Macnab criteria, were obtained in 34.5 % and 62.1 % of patients, respectively. Only one patient had minimal improvement from "Poor" preoperatively to "Fair" postoperatively. This female patient was treated for lumbar disc herniation L5/S1 and had an incomplete fusion at the final follow up. Computed tomography assessment of interbody fusion at the last follow-up showed successful fusion in 91.4 % of patients. ConclusionsUn-instrumented interbody fusion by packing a hollow interspace with cancellous bone allograft chips can be considered as an adjunct to endoscopic foraminal and lateral recess decompression in select patients with validated painful, collapsed, and rigid motion segments. It can be safely done in an outpatient setting at a low burden to patients.