Allograft Bone Block Research Articles

Graft Position, Healing, and Resorption in Anterior Glenohumeral Instability: A Comparison of 4 Glenoid Augmentation Techniques.

The success of glenoid augmentation procedures depends on accurate placement and healing of the graft to the glenoid. Different glenoid augmentation techniques have been described, but no comparative studies between them exist. To assess the bone graft position, healing, and resorption in a group of patients treated with 1 of 4 procedures: arthroscopic anterior bone-block procedure using either (1) fresh-frozen iliac crest allograft or (2) iliac crest autograft, (3) open Latarjet, or (4) arthroscopic Latarjet. Cohort study; Level of evidence, 3. A total of 40 patients (87.5% men; mean age, 29.5 ± 7.9 years) were included, with 10 patients in each of the procedure groups. The graft position in the axial and sagittal planes was assessed on postoperative computed tomography (CT). Graft healing and resorption were assessed in a second CT scan performed 1 year postoperatively. Qualitative variables were compared between the 4 procedures using the chi-square test, and quantitative variables were compared with the Student t test or Mann-Whitney U test. No differences were found between the procedures in the axial or sagittal position. The healing rate was significantly lower in the allograft bone-block group (20%) compared with the autograft bone-block (80%), open Latarjet (90%), and arthroscopic Latarjet (90%) groups (P < .001). Graft resorption developed in 17 of 40 (42.5%) cases overall. Osteolysis occurred in 100% of cases in the allograft bone-block group compared with 50% in the autograft group, 20% in the open Latarjet group, and 0% in the arthroscopic Latarjet group (P < .001). The glenoid surface area on 1-year CT scan was significantly lower in the allograft bone-block group compared with the autograft bone-block, open Latarjet, and arthroscopic Latarjet groups (P < .001). Arthroscopic bone-block, open Latarjet, and arthroscopic Latarjet procedures provided accurate bone graft positioning. However, very high rates of osteolysis and nonunion were observed in the iliac crest fresh-frozen allograft bone-block procedure when compared with the other procedures.

Salvage Reconstruction of a 12-cm Tendon Defect Following Chronic Achilles Rerupture-15-Year Follow-Up: A Case Report.

A 39-year-old man with a chronic Achilles rupture status post (1) failed primary repair and (2) secondary xenograft repair with graft rejection, resulting in a 12-cm Achilles tendon defect, which was reconstructed utilizing an Achilles bone block allograft and flexor hallucis longus (FHL) tendon transfer. At 15-year follow-up, the patient reported good functionality and satisfaction with the repair, with positive patient-reported outcome measures. Physical examination revealed excellent strength and range of motion. Magnetic resonance imaging confirmed the integrity and incorporation of the Achilles/FHL graft composite. This case study provides valuable insight into successful long-term management of complex chronic Achilles ruptures with large defects.

The Triple Varus Knee: A Case Presentation

Background: Knee instability due to posterior cruciate ligament (PCL) and posterolateral corner (PLC) deficiency is a devastating condition that negatively affects patient quality of life. This video presents the surgical management of a triple varus knee, including combined high tibial osteotomy (HTO), revision PCL and PLC reconstruction, and meniscus root repair. Indications: Combined HTO and revision PCL and PLC reconstruction is indicated for patients with previously failed PCL and PLC reconstruction in the setting of varus malalignment. Technique Description: The procedure begins with a medial opening-wedge biplanar HTO, which is fixed with a patient-specific locking plate. The PCL femoral tunnel is drilled via a low anterolateral portal, and the tibial insertion is debrided via a posteromedial portal. The medial meniscus is carefully freed from the posterior capsule, and 2 luggage tag sutures are placed through the posterior root. The PCL tibial tunnel and meniscus root tunnels are drilled via their respective guides. The meniscal sutures are passed through the tunnel but not fixed. An Achilles bone-block allograft is passed through the PCL tibial tunnel and fixed with suspensory fixation and an interference screw on the femoral side, while the tibial side is left free. A peroneal nerve neurolysis is performed. A fibular tunnel is drilled, and a semitendinosus allograft is whip-stitched on both sides and passed through the tunnel. A Beath pin is inserted into the femur, and the tunnel is over drilled. Both limbs of the graft are passed deep to the iliotibial band and into the tunnel. The tibial side of the PCL is fixed with an interference screw at 90° of knee flexion. The PLC grafts are fixed with an interference screw at 30° of knee flexion with slight valgus. The medial meniscus root sutures are tied over a button, with 60° of knee flexion. Screws from osteotomy fixation are replaced as needed. Results: Although outcomes following the combined procedure are lacking, good to excellent clinical outcomes have been reported in isolation following each procedure. Conclusion: A combination of HTO and revision PCL and PLC reconstruction should be considered for patients with persistent instability and/or pain in the setting of triple varus knee. 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.

Extensor Mechanism Reconstruction Using Achilles Tendon Allograft With Suture Tape Augmentation

The management of chronic extensor mechanism injuries represents a significant challenge for orthopaedic surgeons, with numerous options for graft choice and fixation construct, but no clear consensus on which technique achieves optimal outcomes. Although there is little published data regarding outcomes of different fixation methods, small case series have demonstrated modest success using Achilles tendon bone block allografts and transverse patellar screw fixation. In this technical note, we describe a surgical technique for the treatment of a chronic inferior pole patella fracture, with extensor mechanism reconstruction using an Achilles tendon allograft with suture tape augmentation. Our technique describes the use of vertical cannulated screws in the patella for passing tape augmentation sutures, increased construct security by suturing of the Achilles graft directly to the quadriceps tendon, and the use of a post screw in the proximal tibia for suture tape augmentation.

Alveolar ridge reconstruction with a digitally customized bone block allograft

AbstractBackgroundReduced alveolar ridge volume is an often consequence after tooth loss, compromising implant placement and prosthetic rehabilitation. The digital customization of bone block allografts (BBA) is an alternative that incorporates advantages such as intimate contact with the recipient bed, increasing graft stability and reduced surgical time. In addition, enamel matrix derivate (EMD) has attracted interest for its effect on osteogenic gene expression and cell adhesion; few studies have focused on the benefits of bone regeneration with EMD. The aim of this case report is to present the reconstruction of a severely atrophic alveolar ridge defect with a digitally customized bone block allograft (CBBA) in combination with EMD as an adjuvant for bone regeneration and soft tissue healing.MethodsInitially, the digital planning and manufacture of the BBA was performed based on an initial cone beam computed tomography (CBCT) scan. EMD was applied to the recipient site and to the CBBA before graft fixation. After 6 months, bone biopsies were obtained on re‐entry surgery for prosthetically guided implant placement.ResultsClinically, bone block showed good integration with the adjacent tissue and no signs of rejection or necrosis were found. On the histological evaluation, new bone was observed in intimate contact with the allograft and showed viable osteocytes and osteoblasts along its entire length. Residual allograft particles were observed to be highly osteoconductive.ConclusionAccording to the clinical and histological results presented, the digital customization of the BBA allows an ideal graft fit to the recipient bed with excellent results in bone regeneration.

Revision Rates After Primary Allograft ACL Reconstruction by Allograft Tissue Type in Older Patients.

While there is extensive literature on the use of allograft versus autograft in anterior cruciate ligament (ACL) reconstruction, there is limited clinical evidence to guide the surgeon in choice of allograft tissue type. To assess the revision rate after primary ACL reconstruction with allograft and to compare revision rates based on allograft tissue type and characteristics. Cohort study; Level of evidence, 3. Patients who underwent primary allograft ACL reconstructions at a single academic institution between 2015 and 2019 and who had minimum 2-year follow-up were included. Exclusion criteria were missing surgical or allograft tissue type data. Demographics, operative details, and subsequent surgical procedures were collected. Allograft details included graft tissue type (Achilles, bone-patellar tendon-bone [BTB], tibialis anterior or posterior, semitendinosus, unspecified soft tissue), allograft category (all-soft tissue vs bone block), donor age, irradiation duration and intensity, and chemical cleansing process. Revision rates were calculated and compared by allograft characteristics. Included were 418 patients (age, 39 ± 12 years; body mass index, 30 ± 9 kg/m2). The revision rate was 3% (11/418) at a mean follow-up of 4.9 ± 1.4 years. There were no differences in revision rate according to allograft tissue type across Achilles tendon (3%; 3/95), BTB (5%; 3/58), tibialis anterior or posterior (3%; 5/162), semitendinosus (0%; 0/46), or unspecified soft tissue (0%; 0/57) (P = .35). There was no difference in revision rate between all-soft tissue versus bone block allograft (6/283 [2%] vs 5/135 [4%], respectively; P = .34). Of the 51% of grafts with irradiation data, all grafts were irradiated, with levels varying from 1.5 to 2.7 Mrad and 82% of grafts having levels of <2.0 Mrad. There was no difference in revision rate between the low-dose and medium-to high-dose irradiation cohorts (4% vs 6%, respectively; P = .64). Similarly low (0%-6%) revision rates after primary ACL reconstruction were seen regardless of allograft tissue type, bone block versus all-soft tissue allograft, and sterilization technique in 418 patients with mean age of 39 years. Surgeons may consider appropriately processed allograft tissue with or without bone block when indicating ACL reconstruction in older patients.

Reconstructing a Patellar Tendon Rupture Neglected for 14 Years When Anatomic Restoration Is Not Possible: A Case Report.

This case highlights the utility and outcomes of an Achilles tendon bone-block allograft in reconstructing the patellar tendon of a 44-year-old man in the setting of a high-riding, irreducible patella after a chronic patellar tendon rupture of 14 years. In cases of a neglected patellar tendon rupture with an irreducible high-riding patella, an Achilles tendon bone-block allograft can provide the length and tissue necessary to reconstruct the extensor mechanism. Although reconstruction may not be anatomic, patients can still experience great subjective and objective functional improvement with restoration of the extensor mechanism even after delayed reconstruction.

The Use of Cancellous Block Allografts for Reconstruction and Following Implant Failure Associated with Severe Bone Loss: A Prospective Survival and Histomorphometric Study.

A failed implant site is prone to reduced alveolar bone volume, both horizontally and vertically. The present study assessed the outcome of using cancellous bone block allografts for ridge reconstruction following the removal of failed implants associated with severe bone loss. Individuals presenting with failed implants and massive bone loss were included. Cancellous bone block allografts were used for reconstruction of the atrophic alveolar ridge. Radiographic evaluation at 6 months postgrafting revealed favorable bone healing, allowing implant placement. Bone biopsy samples were taken during implant placement. Twenty-four blocks and 58 implants were placed in 16 patients. Over a mean follow-up time of 40 ± 15 months, the mean bone gain was 5 ± 0.5 mm horizontally and 7 ± 0.5 mm vertically. Block and implant survival rates were 96% (1 block failed) and 95% (3 implants failed), respectively. Histomorphometrically, the mean percentage of newly formed bone was 40%, with 20% residual cancellous block allograft and 40% marrow and connective tissue. Cancellous bone block allograft is a viable treatment alternative for reconstructing the alveolar ridge to achieve a successful second reimplantation, even in the presence of initial severe bone loss.

Quadriceps Tendon Reconstruction With Achilles Tendon Bone Block Allograft

Chronic quadriceps tendon ruptures are relatively uncommon albeit debilitating injuries to the knee extensor mechanism. Previous literature demonstrates worse reported outcomes with delayed surgical intervention, and no gold-standard technique currently exists for managing chronic quadriceps tendon ruptures. The goal of this technique is to provide orthopaedic surgeons an additional option that may provide a greater mechanical load to failure and greater allograft acceptance for cases with large tendon gapping or poor tissue quality that may not be viable to other lengthening techniques. We describe the repair of a chronic quadriceps tendon rupture using an Achilles tendon bone block allograft.

Locked Posterior Shoulder Dislocation with Impression Fracture Treated All Arthroscopically With the Use of an Allograft Bone Block a Case Report

Locked posterior shoulder dislocations are uncommon and poses many difficulties in diagnosis. They are often overlooked during initial examination and delayed diagnosis adversely affects healing process. Apart from many open treatment options there are reports of single attempts to treat such cases arthroscopically. We present an original case of a posterior locked dislocation of the shoulder joint with a fracture of the lesser tuberosity followed by reverse Hill-Sachs fracture, treated in a novel fashion all-arthroscopically with the use of allogenic bone graft. According to Constant Shoulder Score that tries to asses functional and subjective performance of the shoulder joint before the operation and after 12 months, we achieved a leap from 11% to 84%. The patient restored almost full range of motion and painless movement in activi-ties of daily life as well as during sports. The use of an arthroscopy reduces the invasiveness of the procedure, improves visualization of the joint and allows augmentation of the bone loss without performing an open approach. We believe that this is A promising method of treatment for selected cases of locked posterior shoulder dislocation.

Esthetic Assessment following Ridge Augmentation, Late Implant Placement and Immediate Esthetic Reconstruction of the Atrophic Anterior Maxilla.

Purpose: Evaluate the esthetic outcome of ridge augmentation using cancellous bone-block allografts, late implant placement, and immediate loading in the atrophic anterior maxilla, by PES (pink esthetic score) and WES (white esthetic score) indexes. Materials and Methods: Retrospective cohort study. Inclusion criteria were bone loss of at least 3 mm horizontally and 3 mm vertically according to preliminary CBCT; ridge augmentation using cancellous bone-block allografts; six months later the implant insertion and immediately loaded. PES-WES index was used for esthetic assessment of soft tissues surrounding the final implant-supported prosthesis (ISP). Results: All twenty-five successive individuals were included. The mean follow-up was 12.1 ± 56 months (range, 42–90 months). The mean PES index and WES index were 7 ± 1.74 (range: 5–10) and 8.4 ± 2.12 (range: 5–10), respectively. The mean total combination of PES index and WES index (PES/WES) was 15.3 ± 2.85 (range: 12–20). All ISPs had an overall score >12 (the defined threshold of clinical acceptability). Conclusions: Ridge augmentation in the atrophic anterior maxilla using cancellous bone-block allografts and immediate loading allows a stable esthetic result of the soft and hard tissues over the years (follow-up of 42–90 months).

Achilles Tendon-Bone Block Allograft for Massive Rotator Cuff Tears With Bony Deficiency of the Greater Tuberosity: A Minimum 2-Year Follow-up Study.

Background:Massive rotator cuff tears associated with greater tuberosity bone loss are challenging to treat. Repairing the rotator cuff without addressing the greater tuberosity deficiency may result in poorer clinical outcomes.Hypothesis:Utilizing an Achilles tendon–bone block allograft to address both the massive rotator cuff tear and greater tuberosity bone loss concurrently can result in improved clinical outcomes.Study Design:Case series; Level of evidence, 4.Methods:The authors performed a retrospective study of patients treated between January 2011 and December 2018 with Achilles tendon–bone block allograft for massive rotator cuff tears associated with greater tuberosity bone loss. The inclusion criteria were massive rotator cuff tear and bony deficiency of the greater tuberosity; patients with a history of bony metabolism disease, connective tissue disease, and previous surgery to the wrist or elbow of the affected limb were excluded. Range of motion, visual analog scale for pain, Constant score, and Single Numeric Assessment Evaluation score were assessed preoperatively and at a minimum of 2 years postoperatively. Radiographs and ultrasound images were evaluated to assess allograft union and rotator cuff integrity.Results:Five patients (3 male and 2 female; mean age, 54.0 ± 12.2 years) were included in the study. The mean follow-up was 80.6 ± 33.7 months. Preoperative to postoperative values improved significantly on the visual analog scale (from 45.8 ± 25.5 to 14.5 ± 14.1; P = .04), Constant score (from 36.8 ± 7.9 to 73.5 ± 3.1; P < .001), and Single Numeric Assessment Evaluation score (from 42.5 ± 26.3 to 82.5 ± 10.4; P = .04). Forward flexion improved significantly from 53° ± 47° to 149° ± 17° (P = .03). Four of the 5 patients achieved bony union. One patient required removal of symptomatic hardware at 6 months postoperatively, and 1 patient required revision surgery at 1 year postoperatively because of progressive osteonecrosis of the humeral head.Conclusion:In patients with massive rotator cuff tears and a greater tuberosity bony deficiency, utilizing an Achilles tendon–bone block allograft to restore the bony defect and reinforce the rotator cuff repair was safe and effective. At a minimum of 2 years postoperatively, most patients demonstrated improved clinical outcomes, tendon healing, and graft incorporation.

The Use of Bone Block Allografts for Vertical Augmentation of the Extremely Atrophic Mandible.

Treatment alternatives based on implant-supported prostheses (ISPs) may be almost impossible in cases with extremely atrophic mandibles. Vertical bone augmentation is then the only possibility to achieve an ISP. The consequences of vertical augmentation in extremely atrophic mandibles (≤ 10-mm bone height) of edentulous patients using allogeneic block grafts via a submental approach were assessed. The recorded parameters were sex, age, physical status, hospitalization duration, postoperative complications, implant characteristics (length, diameter), early and late implant failure (yes/no; primary outcome variable). Bone height was measured at three points using the pre-grafting and pre-implant placement CBCT imaging. The difference between the measurements was defined as bone gain (primary outcome variable). Sixteen patients (2 men, 14 women) were included. The preoperative bone height ranged from 4 to 10 mm. A mean of 5.3 ± 1 months was allowed for graft consolidation. The average bone height gain was 11.2 ± 3.1 mm. Two to six dental implants were placed in the grafted bone. Early implant failure occurred in 4 out of 73 (5.5%). Follow-up ranged from 12 to 92 (mean: 48 ± 30) months. All patients were followed for more than a year, and two additional late implant failures were recorded, rendering a 92% cumulative survival rate. Bone grafting using allogeneic bone blocks via a submental approach seems to be a promising solution for reconstruction of the extremely atrophic mandible.

Esthetic Assessment Succeeding Anterior Atrophic Maxilla Augmentation with Cancellous Bone-Block Allograft and Late Restoration Loading.

Background: Various conditions may lead to bony deficiency in the anterior maxilla. The present study evaluated esthetic (PES—pink esthetic score and WES—white esthetic score) results after augmentation of the anterior atrophic maxilla using cancellous bone-block allograft followed by implant placement and late (conventional) loading. Methods: Cohort study that included 33 patients with missing teeth in the upper anterior region characterized by extensive bone loss. Allogeneic cancellous bone-blocks were used for augmentation. Six months later, a dental implant was inserted. After a waiting time of an additional six-months, implant exposure and reconstruction were performed. The mean follow-up period was 62.93 ± 17.37 months (range 19–82 months). Results: The mean value of PES/WES was 17.8 ± 2.78. All patients had a PES/WES value above 12 (threshold value defined as clinically acceptable esthetics). The mean value of PES was 9.0 ± 1.79 and the mean value of WES was 8.8 ±1.84. Conclusions: Bone augmentation of the anterior atrophic maxilla using cancellous block-allograft and late loading supports achievement of a predictable esthetic result with long-term stability of soft and hard tissues around implant-supported reconstructions.

Distal Tibial Allograft Bone Block for Posterior Shoulder Instability with Bone Loss: A Case Series

Distal Tibial Allograft Bone Block for Posterior Shoulder Instability with Bone Loss: A Case Series

Biologic Augmentation of Tibiotalocalcaneal Arthrodesis with Autologous Bone Block is Associated with High Rates of Fusion

Category:Ankle; HindfootIntroduction/Purpose:Tibiotalocalcaneal (TTC) arthrodesis is an established salvage procedure for severe deformities of the hindfoot. Despite its prevalence, end-stage pathology, systemic comorbidities, and the physical demands of surgery often precipitate unsuccessful outcomes, with nonunion rates as high as 85% in medically complex patients. Given the considerable morbidity associated with TTC arthrodesis, there has been recent interest in maximizing the physiologic potential of fusion by means of surgical technique, osteoinductive and osteoconductive biological agents, and vascularized bone flaps. Here, we present a novel approach to TTC arthrodesis using femoral head allograft bone block, bone marrow aspirate, and demineralized bone matrix (DBM) in the absence of tourniquet. Additionally, we explore the role of the medial femoral condyle (MFC) free flap as a reconstructive adjunct to arthrodesis.Methods:The sample consisted of 14 patients presenting to a tertiary care facility for reconstructive limb salvage. TTC arthrodesis was performed without tourniquet and biologically augmented with fresh-frozen femoral head allograft, pelvic bone marrow aspirate, and DBM. Three patients with severe soft tissue defects also underwent vascularized osseous reconstruction with MFC free flap. Recovery protocol included three months of prolonged non-weightbearing mechanical stabilization followed by conversion to weightbearing AFO boot for one year. Post-operative plain radiographs and computed tomography (CT) scans were assessed for fusion at regular follow-up. After fusion, participants completed a survey on patient-reported outcomes, which included the modified Foot Function Index (FFI) and Patient-Reported Outcomes Measurement Information System (PROMIS) scales for pain and physical function.Results:Successful TTC fusion was documented on plain radiograph in 13 patients (92.9%) and confirmed via CT in 10 patients (90.9%). The mean time-to-fusion was 183.2 +- 83.2 days. One patient (7.1%) failed to achieve fusion and underwent amputation secondary to infectious wound complications. Patients who underwent vascularized bone grafting had more robust healing and significantly shorter time-to-fusion (112.3 +- 31.7 days vs. 204.4 +- 82.7 days, p = 0.05). The mean patient-reported FFI score was found to be 40.96% +- 23.08%, indicating mild-to-moderate impairment in foot function. Similarly, PROMIS data revealed that patients who underwent TTC arthrodesis had a pain T-score of 58.34 (z = 0.83) and a physical function T-score of 39.00 (z = - 1.10), corresponding to mild pain and moderate impairment, respectively.Conclusion:We sought to biologically optimize the osteoinductive and osteoconductive potential of TTC arthrodesis using femoral head allograft bone block, bone marrow aspirate, and DBM in the absence of tourniquet. This approach resulted in excellent rates of fusion with minimal pain and preserved function of the lower extremity. Osseous healing was significantly enhanced by MFC flap in patients with soft tissue defects. We, therefore, recommend biologic augmentation of TTC arthrodesis as a viable salvage option for patients facing amputation or other undesirable outcomes.

Histomorphometrical Assessment of Sinus Augmentation Using Allograft (Particles or Block) and Simultaneous Implant Placement

The aim of the present study was to compare the clinical, radiological and histomorphometrical outcome of simultaneous implant placement following augmentation of atrophic maxillary sinuses using allograft (block or particles). Consecutive patients with maxillary residual alveolar ridge height ≤3 mm, scheduled for sinus floor augmentation with simultaneous implant placement, were randomly included. Allograft bone-block or bone-particles served as grafting material. Simultaneously, dental implants were inserted. Biopsies were taken at second stage surgery (after 9 months) for histomorphometric evaluation. Initially 38 sinus augmentations (29 individuals) were allocated for the study. In 4 out of 21(19%) sinuses using particles it was impossible to stabilize the implants and a second stage insertion was preferred, leaving 34 sinuses for histomorphometric evaluation. The difference in the ability to perform simultaneous implant placement was statistically significant (p < 0.05). Ninety implants were inserted simultaneously. All implants osseointegrated. None of the implants was lost up to the end of follow-up time (Range 50–120 months, Mean 74.5 ± 13.5 months). Bone gain radiographically 12.3 ± 1 mm vs. 11.2 ± 1 mm (block vs. particles respectively) and new bone formation histomorphometrically 27.7 ± 15% vs. 32.1 ± 19% (block vs. particles respectively) showed no statistically significant differences between the two groups. Sinus augmentation using allograft (particles or block) and simultaneous implant placement is predictable. All outcome parameters are similar when sinus bone-blocks augmentation is compared to bone-particles augmentation (radiological new bone gain, implant survival, hisomorphometricly new bone formation) despite the ability to stabilize implants, when placed simultaneously with sinus augmentation. Blocks may be advisable when simultaneous implant placement is imperative in cases with residual alveolar bone height ≤3 mm.

Fusion rates support wired allograft combined with instrumented craniocervical fixation in the paediatric population

BackgroundOccipitocervical and atlantoaxial instability in the pediatric population is a rare and challenging condition to treat. Variable surgical techniques have been employed to achieve fusion. The study aimed to assess bony fusion with rigid craniocervical fixation using an allograft bone block to serve as scaffold for bony fusion.MethodsThis is a single center case series from a tertiary referral neurosurgical center. The series includes 12 consecutive pediatric patients with rigid craniocervical fusion between 2006 and 2014. The primary outcome was bony fusion as assessed by computed tomography and flexion-extension radiographs. The authors did not receive external funding for this study.ResultsTwelve patients (age 1–15 years) were operated with a median imaging follow-up time of 22 months (range 6–69 m). A modified Gallie fusion technique with a tightly wired allograft bone block was used in 10 of 13 procedures. One patient underwent re-fixation due to screw breakage. Eleven out of 13 procedures resulted in a stable construct with bony fusion. All 10 patients operated with the modified Gallie fusion technique with sublaminar wiring of allograft bone block had bony fusion. No post-operative complications of the posterior fixation procedure were noted.ConclusionsThe modified Gallie fusion technique with allograft bone block without post-operative immobilization achieved excellent fusion. We conclude there is no need to use autograft or BMPs in craniocervical fusion in the pediatric population, which avoids related donor-site morbidity.Level of evidenceLevel IV—case series; therapeutic.

Demographics and Distal Tibial Dimensions of Suitable Distal Tibial Allografts for Glenoid Reconstruction

To evaluate whether characteristics such as age, height, weight, sex, or body mass index affected the distal tibial dimensions and radius of curvature (ROC) of a potential donor for anterior glenoid augmentation. A retrospective review of magnetic resonance imaging of ankles without bony trauma was performed, and the anteroposterior (AP) and medial-lateral (ML) distances and ROC of the tibial plafond articular surface were measured. Demographic characteristics, including age, sex, height, weight, and body mass index, were recorded. A total of 141 imaging studies were included (73 men and 68 women; average age, 38.2 ± 12.65years). All potential specimens accommodated harvest of a 10× 22-mm distal tibial allograft bone block. Men had greater ML (42.74cm [95% confidence interval (CI), 42.09-43.39cm] vs 38.01cm [95% CI, 37.30-38.72cm]; P < .001) and AP (38.16cm [95% CI, 37.47-38.85cm] vs 34.57cm [95% CI, 33.97-35.17cm]; P < .001) dimensions. Significant moderately positive correlations were found for AP dimensions with height (r= 0.584, P < .001) and weight (r= 0.383, P < .001) and for ML dimensions with height (r=0.711, P < .001) and weight (r= 0.467, P < .001). ROC was positively correlated with height (r= 0.509, P < .001) and weight (r= 0.294, P < .001). Patient age was not related to either the AP or ML distal tibial dimensions or ROC. After magnetic resonance imaging analysis, all potential donors permitted harvest of a standard-sized distal tibial allograft irrespective of sex or common anthropometric measures, and 85.8% showed distal tibial morphology acceptable for glenoid augmentation. AP and ML graft dimensions and ROC correlated significantly with height and weight. Level II, diagnostic study.

Anterior atrophic mandible restoration using cancellous bone block allograft.

Bone block grafting may be required to restore the alveolar process prior to implant placement in Kennedy Class IV partial edentulism of the anterior mandible. Evaluate the application of allograft cancellous bone blocks for the augmentation of the anterior atrophic mandible. Fourteen consecutive patients underwent augmentation with cancellous bone block allografts in the anterior mandible. A bony deficiency of at least 3 mm horizontally and up to 3 mm vertically according to computerized tomography para-axial reconstruction served as inclusion criteria. Following 6 months, 26 implants were placed and a cylindrical sample core was collected. All specimens were prepared for histological and histomorphometrical examination. The rehabilitation scheme was two dental implants, placed in the lateral incisor area, supporting a 4-unit implant-supported prosthesis. Twenty-four blocks were placed in 14 patients. Mean follow-up was 26 ± 17 months. Mean bone gain was 5 ± 0.5 mm horizontally, and 2 ± 0.5 mm vertically. Twenty-six implants were used. Marginal bone loss at last follow up did not extend beyond the first thread. Block and implant survival rates were 91.6% and 100%, respectively. All patients but one received a fixed implant-supported prosthesis. Histomorphometrically, the mean fraction of the newly formed bone was 42%, that of the residual cancellous block-allograft 17%, and of the marrow and connective tissue 41%. The potential of cancellous bone block allografts for reconstruction of Kennedy Class IV partial edentulism in the anterior mandible seems promising but still has to be evaluated scientifically in long-term observations.