Showing papers on "Iliac crest published in 2010"

Bone mineralization defects and vitamin D deficiency: Histomorphometric analysis of iliac crest bone biopsies and circulating 25-hydroxyvitamin D in 675 patients

Abstract: Parathyroid hormone (PTH) is only one measurable index of skeletal health, and we reasoned that a histomorphometric analysis of iliac crest biopsies would be another and even more direct approach to assess bone health and address the required minimum 25-Hydroxyvitamin D [25(OH)D] level. A cohort from the northern European population with its known high prevalence of vitamin D deficiency therefore would be ideal to answer the latter question. We examined 675 iliac crest biopsies from male and female individuals, excluding all patients who showed any signs of secondary bone diseases at autopsy. Structural histomorphometric parameters, including osteoid indices, were quantified using the Osteomeasure System according to ASBMR standards, and serum 25(OH)D levels were measured for all patients. Statistical analysis was performed by Student's t test. The histologic results demonstrate an unexpected high prevalence of mineralization defects, that is, a pathologic increase in osteoid. Indeed, 36.15% of the analyzed patients presented with an osteoid surface per bone surface (OS/BS) of more than 20%. Based on the most conservative threshold that defines osteomalacia at the histomorphometric level with a pathologic increase in osteoid volume per bone volume (OV/BV) greater than 2% manifest mineralization defects were present in 25.63% of the patients. The latter were found independent of bone volume per trabecular volume (BV/TV) throughout all ages and affected both sexes equally. While we could not establish a minimum 25(OH)D level that was inevitably associated with mineralization defects, we did not find pathologic accumulation of osteoid in any patient with circulating 25(OH)D above 75 nmol/L. Our data demonstrate that pathologic mineralization defects of bone occur in patients with a serum 25(OH)D below 75 nmol/L and strongly argue that in conjunction with a sufficient calcium intake, the dose of vitamin D supplementation should ensure that circulating levels of 25(OH)D reach this minimum threshold (75 nmol/L or 30 ng/mL) to maintain skeletal health.

Normalization of Glenohumeral Articular Contact Pressures After Latarjet or Iliac Crest Bone-Grafting

Abstract: Background: Multiple bone-grafting procedures have been described for patients with glenoid bone loss and shoulder instability. The purpose of this study was to investigate the alterations in glenohumeral contact pressure associated with the placement and orientation of Latarjet or iliac crest bone graft augmentation and to compare the amount of glenoid bone reconstruction with two coracoid face orientations. Methods: Twelve fresh-frozen cadaver shoulders were tested in static positions of humeral abduction (30°, 60°, and 60° with 90° of external rotation) with a 440-N compressive load. Glenohumeral contact pressure and area were determined sequentially for (1) the intact glenoid; (2) a glenoid with an anterior bone defect involving 15% or 30% of the glenoid surface area; (3) a 30% glenoid defect treated with a Latarjet or iliac crest bone graft placed 2 mm proud, placed flush, or recessed 2 mm in relation to the level of the glenoid; and (4) a Latarjet bone block placed flush and oriented with either the lateral (Latarjet-LAT) or the inferior (Latarjet-INF) surface of the coracoid as the glenoid face. The amount of glenoid bone reconstructed was compared between the Latarjet-LAT and Latarjet-INF conditions. Results: Bone grafts in the flush position restored the mean peak contact pressure to 116% of normal when the iliac crest bone graft was used (p < 0.03 compared with the pressure with the 30% defect), 120% when the Latarjet-INF bone block was used (p < 0.03), and 137% when the Latarjet-LAT bone block was used (p < 0.04). Use of the Latarjet-LAT bone block resulted in mean peak pressures that were significantly higher than those associated with the iliac crest bone graft (p < 0.02) or the Latarjet-INF bone block (p < 0.03) at 60° of abduction and 90° of external rotation. With the bone grafts placed in a proud position, peak contact pressure increased to 250% of normal (p < 0.01) in the anteroinferior quadrant and there was a concomitant increase in the posterosuperior glenoid pressure to 200% of normal (p < 0.02), indicating a shift posteriorly. Peak contact pressures of bone grafts placed in a recessed position revealed high edge-loading. Augmentation with the Latarjet-LAT bone block led to restoration of the glenoid articular contact surface from the 30% defect state to a 5% defect state. Augmentation of the 30% glenoid defect with the Latarjet-INF bone block resulted in complete restoration to the intact glenoid articular surface area. Conclusions: Glenohumeral contact pressure is optimally restored with a flush iliac crest bone graft or with a flush Latarjet bone block with the inferior aspect of the coracoid becoming the glenoid surface. Bone grafts placed in a proud position not only increase the peak pressure anteroinferiorly, but also shift the articular contact pressure to the posterosuperior quadrant. Glenoid bone augmentation with a Latarjet bone block with the inferior aspect of the coracoid as the glenoid surface resulted in complete restoration of the 30% anterior glenoid defect to the intact state. These findings indicate the clinical utility of a flush iliac crest bone graft and utilization of the inferior surface of the coracoid as the glenoid face for glenoid bone augmentation with a Latarjet graft.

Evaluation of Maxillary Alveolar Reconstruction Using a Resorbable Collagen Sponge with Recombinant Human Bone Morphogenetic Protein-2 in Cleft Lip and Palate Patients

Abstract: Introduction: A resorbable collagen matrix with recombinant human bone morphogenetic protein (rhBMP-2) was compared with traditional iliac crest bone graft for the closure of alveolar defects during secondary dental eruption. Methods: Sixteen patients with unilateral cleft lip and palate, aged 8 to 12 years, were selected and randomly assigned to group 1 (rhBMP-2) or group 2 (iliac crest bone graft). Computed tomography was performed to assess both groups preoperatively and at months 6 and 12 postoperatively. Bone height and defect volume were calculated through Osirix Dicom Viewer (Pixmeo, Apple Inc.). Overall morbidity was recorded. Results: Preoperative and follow-up examinations revealed progressive alveolar bone union in all patients. For group 1, final completion of the defect with a 65.0% mean bone height was detected 12 months postoperatively. For group 2, final completion of the defect with an 83.8% mean bone height was detected 6 months postoperatively. Dental eruption routinely occurred in both...

Graft options in posterolateral and posterior interbody lumbar fusion.

Abstract: Study design Review article, review of literature. Objective To review the bone graft options that exist for posterolateral and posterior interbody lumbar fusion. Summary of background data As the number of lumbar fusion surgeries has increased over the last decade, alternative methods of grafting have been developed. Iliac crest autograft bone has traditionally been used for lumbar fusion. The downside to this graft option, however, is donor site morbidity. Methods The current literature on alternatives to iliac crest autograft bone for obtaining lumbar fusion was reviewed. Results Platelet gels, demineralized bone matrix, synthetic bone graft, and bone morphogenetic protein are potential options for bone graft supplementation or substitution. In preclinical studies, platelet gels have been beneficial to bone growth when combined with autograft, but clinical studies do not support the use of platelet gel in posterolateral lumbar fusion. Preclinical studies of demineralized bone matrix have shown significant variability in the osteoinductive properties of the available products, and clinical data showing efficacy is limited. The use of synthetic bone graft material (ceramics) in lumbar fusion surgery is increasing. Calcium phosphate compounds (i.e., beta-tricalcium phosphate and hydroxyapetite) are most commonly used and are often combined with type I collagen to form a matrix. These materials provide an osteoconductive scaffold for bony ingrowth and can be combined with bone marrow aspirate or used as a carrier for osteogenic factors. Bone morphogenetic protein (rhBMP-2) has been shown to provide similar or even increased fusion rates over autograft iliac crest bone. There are, however, potential safety concerns associated with the use of bone morphogenetic protein that are not fully understood. Conclusion Several alternatives to iliac crest autograft bone provide promising early clinical results in achieving posterolateral and posterior interbody lumbar fusion.

Clinical and histomorphometric evaluation of extraction sockets treated with an autologous bone marrow graft.

Abstract: Purpose: The aim of this study was to evaluate the potential of an autologous bone marrow graft in preserving the alveolar ridges following tooth extraction. Materials: Thirteen patients requiring extractions of 30 upper anterior teeth were enrolled in this study. They were randomized into two groups: seven patients with 15 teeth to be extracted in the test group and six patients with 15 teeth to be extracted in the control group. Hematologists collected 5ml of bone marrow from the iliac crest of the patients in the test group immediately before the extractions. Following tooth extraction and elevation of a buccal full-thickness flap, titanium screws were positioned throughout the buccal to the lingual plate and were used as reference points for measurement purposes. The sockets were grafted with an autologous bone marrow in the test sites and nothing was grafted in the control sites. After 6 months, the sites were re-opened and bone loss measurements for thickness and height were taken. Additionally, before implant placement, bone cores were harvested and prepared for histologic and histomorphometric evaluation. Results: The test group showed better results (Po0.05) in preserving alveolar ridges for thickness, with 1.14 " 0.87mm (median 1) of bone loss, compared with the control group, which had 2.46 " 0.4mm (median 2.5) of bone loss. The height of bone loss on the buccal plate was also greater in the control group than in the test group (Po0.05), 1.17 " 0.26mm (median 1) and 0.62! 0.51 (median 0.5), respectively. In five locations in the control group, expansion or bone grafting complementary procedures were required to install implants while these procedures were not required for any of the locations in the test group. The histomorphometric analysis showed similar amounts of mineralized bone in both the control and the test groups, 42.87 " 11.33% (median 43.75%) and 45.47 " 7.21% (median 45%), respectively. Conclusion: These findings suggest that the autologous bone marrow graft can contribute to alveolar bone repair after tooth extraction.

Donor site morbidity after bone harvesting from the anterior iliac crest

Abstract: Objectives Autologous bone grafting is a common, standard procedure in maxillofacial surgery. We investigated complications of harvesting bone from the anterior iliac crest. Study design A retrospective analysis with a 2-year observational period included 75 patients who had undergone iliac bone grafting. Two techniques were examined: the closed osteotomy using a cylinder osteotome (Shepard) and an open procedure with a saw. Results One major complication, a fracture of the anterior superior iliac spine, was observed (0.7%). Regarding long-term morbidity, 3 patients (4%) suffered from persistent pain and 2 (2.7%) from persistent sensory disturbance. A correlation by gender showed greater severity of pain directly after graft harvesting in women ( P Wilcoxon ≤ .001). Harvesting of corticocancellous blocks caused more pain than with the cylinder osteotome ( P Median ≤ .07). Conclusion The morbidity after iliac crest harvesting was found to be moderate to low, but the procedure is still necessary and frequently used.

Treatment of chondral defects of the knee with one step matrix-assisted technique enhanced by autologous concentrated bone marrow: In vitro characterisation of mesenchymal stem cells from iliac crest and subchondral bone

Abstract: Cartilage repair is still an unsolved problem. In the last years many cell-based treatments have been proposed, in order to obtain good regeneration of cartilage defects. The Autologous Matrix-Induced Chondrogenesis technique (AMIC ® ) combines the micro-fracture procedure with the use of a specific biological membrane. The phenotypic feature of bone marrow cell population, harvested from iliac crest and knee subchondral bone of patients treated with the AMIC ® technique, enhanced by autologous concentrated bone marrow, was analysed to evaluate potential variations of the cell population. Samples of eleven patients, with isolated chondral lesions grade III or IV were treated with the AMIC ® technique, enhanced by the use of autologous concentrated bone marrow. A small fraction of bone marrow samples, both from iliac crest and from the created micro-fractures, was analysed by FACS analysis and then cultured to verify their proliferative and differentiation potential. An average of 0.04% of concentrated bone marrow cells harvested from the iliac crest, presented mesenchymal stem cell phenotype (CD34 − /CD45 low /CD271 high ), whereas just 0.02% of these cells were identified from the samples harvested during the creation of micro-fractures at the knee. After two passages in culture, cells expressed a peculiar profile for MSC. Only MSC from bone marrow could be long-term propagated and were able to efficiently differentiate in the cultures. Although the AMIC ® approach has many advantages, the surgical technique in the application of the microfracture technique remains essential and affects the final result.

Treatment of nontraumatic osteonecrosis of the femoral head with the implantation of core decompression and concentrated autologous bone marrow containing mononuclear cells

Abstract: Since self-limited repair ability of the necrotic lesion may be a cause for failure of the technique, the possibility has been raised that bone marrow mononuclear cells (BMMCs) containing BMSCs implanted into a necrotic lesion of the femoral head with core decompression (CD) may be of benefit in the treatment of this condition. For this reason, we studied the implantation of the concentrated autologous bone marrow containing mononuclear cells in necrotic lesion of the femoral head to determine the effect of the method. The study included 45 patients (59 hips, 9 females, 36 males; mean age 37.5 years, range 16–56 years) with stages I–IIIA nontraumatic avascular necrosis of the femoral head according to the system of the Association Research Circulation Osseous. Concentrated bone marrow (30–50 ml) containing mononuclear cells has been gained from autologous bone marrow (100–180 ml) obtained from the iliac crest of patient with the cell processor system. Concentrated bone marrow was injected through a CD channel into the femoral head. The outcome was determined by the changes in the Harris hip score, by progression in radiographic stages, and by the need for hip replacement. The mean follow-up was 27.6 months (range 12–40 months). Pre- and post-operative evaluations showed that the mean Harris hip score increased from 71 to 83. Clinically, the overall success is 79.7%, and hip replacement was done in 7 of the 59 hips (11.9%). Radiologically, 14 of the 59 hips exhibited femoral head collapse or narrowing of the coxofemoral joint space, and the overall failure rate is 23.7%. The number of BMMCs increased from 12.2 ± 3.2 × 106/ml to 35.2 ± 12 × 106/ml between pre-concentration and post-concentration. The concentrated autologous bone marrow containing mononuclear cells implantation relieves hip pain, prevents the progression of osteonecrosis. Therefore, it may be the treatment of choice particularly in stages I–II nontraumatic osteonecrosis of the femoral head.

Bone union rate with autologous iliac bone versus local bone graft in posterior lumbar interbody fusion.

Abstract: Study design A retrospective clinical study with a long-term follow-up in a single facility. Objective The purpose of this study is to compare bone union rate between autologous iliac crest bone graft and local bone graft in patients treated by posterior lumbar interbody fusion (PLIF) using carbon cage for single-level interbody fusion. Summary of background data Recently, a number of authors have reported on local bone grafting using bone that is obtained from laminectomy, and have indicated that the achieved fusion rate is similar to that of autologous iliac bone grafting. However, there is no report comparing the fusion rates between autologous iliac bone and local bone graft with a detailed follow-up of fusion progression. Methods The subjects were 101 patients whose course could be observed for at least 2 years. The diagnosis was lumbar spinal canal stenosis in 14 patients, herniated lumbar disc in 19 patients, and degenerative spondylolisthesis in 68 patients. Single interbody PLIF was performed using iliac bone graft in 54 patients and local bone graft in 47 patients. Existence of pseudarthrosis on X-P (anteroposterior and lateral view) was investigated during the same follow-up period. Results No significant differences were found in operation time and blood loss. Significant differences were also not observed in fusion grade at any follow-up period or in fusion progression between the 2 groups. Donor site pain continued for more than 3 months in 6 cases (11%). The final fusion rate was 94.5% versus 95.8%. Conclusion Fusion results from the local bone group and the autologous iliac bone group were nearly identical. Furthermore, fusion progression was nearly identical. Complications at donor sites were seen in 17% of the cases. From the aforementioned results, it was concluded that local bone graft is as beneficial as autologous iliac bone graft for PLIF at a single level.

Deficient bone formation in idiopathic juvenile osteoporosis: a histomorphometric study of cancellous iliac bone.

Abstract: Idiopathic juvenile osteoporosis (IJO), a rare cause of osteoporosis in children, is characterized by the occurrence of vertebral and metaphyseal fractures. Little is known about the histopathogenesis of IJO. We analyzed by quantitative histomorphometry iliac crest biopsies from 9 IJO patients (age, 10.0-12.3 years; 7 girls) after tetracycline labeling. Results were compared with identically processed samples from 12 age-matched children without metabolic bone disease and 11 patients with osteogenesis imperfecta type I. Compared with healthy controls, cancellous bone volume (BV) was markedly decreased in IJO patients (mean [SD]: 10.0% [3.1%] vs. 24.4% [3.8%]), because of a 34% reduction in trabecular thickness (Tb.Th) and a 37% lower trabecular number (Tb.N; p < 0.0001 each; unpaired t-test). Bone formation rate (BFR) per bone surface was decreased to 38% of the level in controls (p = 0.0006). This was partly caused by decreased recruitment of remodeling units, as shown by a trend toward lower activation frequency (54% of the control value; p = 0.08). Importantly, osteoblast team performance also was impaired, as evidenced by a decreased wall thickness (W.Th; 70% of the control value; p < 0.0001). Reconstruction of the formative sites revealed that osteoblast team performance was abnormally low even before mineralization started at a given site. No evidence was found for increased bone resorption. Compared with children with osteogenesis imperfecta (OI), IJO patients had a similarly decreased cancellous BV but a much lower bone turnover. These results suggest a pathogenetic model for IJO, in which impaired osteoblast team performance decreases the ability of cancellous bone to adapt to the increasing mechanical needs during growth. This will finally result in load failure at sites where cancellous bone is essential for stability.

Surgical treatment of upper, middle and lower cervical injuries and non-unions by anterior procedures

Abstract: The goals of any treatment of cervical spine injuries are: return to maximum functional ability, minimum of residual pain, decrease of any neurological deficit, minimum of residual deformity and prevention of further disability. The advantages of surgical treatment are the ability to reach optimal reduction, immediate stability, direct decompression of the cord and the exiting roots, the need for only minimum external fixation, the possibility for early mobilisation and clearly decreased nursing problems. There are some reasons why those goals can be reached better by anterior surgery. Usually the bony compression of the cord and roots comes from the front therefore anterior decompression is usually the procedure of choice. Also, the anterior stabilisation with a plate is usually simpler than a posterior instrumentation. It needs to be stressed that closed reduction by traction can align the fractured spine and indirectly decompress the neural structures in about 70%. The necessary weight is 2.5 kg per level of injury. In the upper cervical spine, the odontoid fracture type 2 is an indication for anterior surgery by direct screw fixation. Joint C1/C2 dislocations or fractures or certain odontoid fractures can be treated with a fusion of the C1/C2 joint by anterior transarticular screw fixation. In the lower and middle cervical spine, anterior plating combined with iliac crest or fibular strut graft is the procedure of choice, however, a solid graft can also be replaced by filled solid or expandable vertebral cages. The complication of this surgery is low, when properly executed and anterior surgery may only be contra-indicated in case of a significant lesion or locked joints.

Anatomy and landmarks for the superior and middle cluneal nerves: application to posterior iliac crest harvest and entrapment syndromes.

Abstract: Object. To date, only scant descriptions of the cluneal nerves are available. As these nerves, and especially the superior group, may be encountered and injured during posterior iliac crest harvest for spinal arthrodesis procedures, the present study was performed to better elucidate their anatomy and to provide anatomical landmarks for their localization. Methods. The superior and middle cluneal nerves were dissected from their origin to termination in 20 cadaveric sides. The distance between the posterior superior iliac spine (PSIS) and superior cluneal nerves at the iliac crest and the distance between this bony prominence and the origin of the middle cluneals were measured. The specific course of each nerve was documented, and the diameter and length of all cluneal nerves were measured. Results. Superior and middle cluneal nerves were found on all sides. An intermediate superior cluneal nerve and lateral superior cluneal nerve were not identified on 4 and 5 sides, respectively. The superior cluneal nerves always passed through the psoas major and paraspinal muscles and traveled posterior to the quadratus lumborum. The mean diameters of the superior and middle cluneal nerves were 1.1 and 0.8 mm, respectively. From the PSIS, the superior cluneal branches passed at means of 5, 6.5, and 7.3 cm laterally on the iliac crest. At their origin, the middle cluneal nerves had mean distances of 2 cm superior to the PSIS, 0 cm from the PSIS, and 1.5 cm inferior to the PSIS. In their course, the middle cluneal nerves traversed the paraspinal muscles attaching onto the dorsal sacrum. Conclusions. Knowledge of the cutaneous nerves that cross the posterior aspect of the iliac crest may assist in avoiding their injury during bone harvest. Additionally, an understanding of the anatomical pathway that these nerves take may be useful in decompressive procedures for entrapment syndromes involving the cluneal nerves. (DOI: 10.3171/2010.3.SPINE09747) key w o RDS • anatomy • iliac crest • nerve injury • anatomical landmark • gluteal region

Iliac bone histomorphometry in children with newly diagnosed inflammatory bowel disease

Abstract: Children with inflammatory bowel disease (IBD) manifest low bone mass; the cause remains unclear. We performed transilial bone biopsies in 20 IBD children at diagnosis and found a mild cortical bone deficit and slow bone turnover. It is possible that low mechanical stimulation due to inadequate muscle mass contributes to the bone deficit. Children with newly diagnosed IBD can have low bone mineral density and disturbed bone metabolism, but the tissue level characteristics of the bone involvement in pediatric IBD have not been elucidated. In the present study, we evaluated the skeletal status, including static histomorphometry on transiliac bone samples, in 20 patients (age range 8.4 to 17.7 years, 12 boys) with newly diagnosed IBD and compared results to published normative data. Despite normal height (mean Z-score 0.04, SD 1.2), areal bone mineral density at the lumbar spine was moderately low (mean age- and sex-specific Z-score −0.8, SD 1.1). Total body bone mineral content and lean mass were low for age and sex as well (mean Z-scores −1.2, SD 0.9 and −2.0, SD 0.9, respectively). Biochemical bone markers indicated low bone formation and resorption activity. Bone histomorphometry revealed a slightly low cortical width (mean 23%, SD 25%, below the result expected for age) but a normal amount of trabecular bone. The percentage of trabecular bone surface covered by osteoid or osteoclasts was low, suggesting that both bone formation and bone resorption were suppressed. Our results indicate that young patients manifest a mild cortical bone deficit at the iliac crest and slow trabecular bone turnover even at diagnosis, in the setting of IBD.

Foraminoplastic ventral epidural approach for removal of extruded herniated fragment at the L5-S1 level.

Abstract: The 'foraminoplastic' ventral epidural approach and its advantages in the treatment of extruded disk herniation at the L5-S1 level are described. Percutaneous endoscopic lumbar discectomy is a minimally invasive procedure applicable to various types of lumbar disk herniation, but the L5-S1 disk space is still challenging to access due to anatomic limitations such as high iliac crest or severely narrowed foramen. The 'foraminoplastic' ventral epidural approach was performed in 25 patients with herniated disk radiculopathy at L5-S1 from March 2003 to May 2004. Their mean age was 39.2 years (range 20-67 years) and the mean follow-up duration was 32.5 months (range 28-42 months). During the procedure, 'foraminoplasty' was performed by undercutting the hypertrophic superior facet with the endoscopic bone cutter under C-arm guidance. The clinical result was assessed according to the visual analogue scale (VAS) and Oswestry disability index (ODI). Preoperative mean VAS score of 7.4 for leg pain fell to 1.6 postoperatively and mean preoperative ODI of 55.5% improved to 16.9% postoperatively, both showing significant improvements (p < 0.001). Mean hospital stay was 14.2 hours. Twenty-two patients had the favorable outcomes. Two patients required conversion to open microdiscectomy due to incomplete decompression and recurrent disk herniation. The 'foraminoplastic' approach is a safe and efficient surgical option for L5-S1 disk herniation even in patients with high iliac crest and narrow foramen.

Osteotomy of distal radius fracture malunion using a fast remodeling bone substitute consisting of calcium sulphate and calcium phosphate

Abstract: Malunion after a distal radius fracture can be treated with an osteotomy of the distal radius. Autologous iliac crest bone graft is often used to fill the gap, but the procedure is associated with donor site morbidity. In this study a novel fast resorbing biphasic bone substitute consisting of a mixture of calcium sulphate and calcium phosphate is used (Cerament BoneSupport AB, Sweden). Fifteen consecutive patients, with a mean age of 52 (27-71) years were included. All had a malunion after a distal radius fracture and underwent an osteotomy. A fragment specific fixation system, TriMed (TriMed, Valencia, CA), consisting of a Buttress Pin and a Radial Pin Plate were used for fixation and a calcium sulphate and calcium phosphate mixture as bone substitute. The patients were followed for 1 year. Grip strength increased from 61 (28-93)% of the contralateral hand to 85 (58-109)%, p < 0.001. DASH scores decreased from 37 (22-61) to 24 (2-49) p = 0.003. Radiographically all osteotomies healed. An increase of ulnar variance was noted during healing from 1.8 mm immediately postoperatively to 2.6 mm at final follow up. Osteotomy can increase grip strength and decease disability after a malunited fracture. In the present series the bone substitute was replaced by bone, but a minor loss of the achieved radiographic correction was noted in some patients during osteotomy healing. A more rigid fixation may improve the radiographic outcome with this kind of bone substitute.

Controversies in skull reconstruction.

Abstract: In the early 1980s, it was shown that bone from the skull (membranous bone) maintained its volume to a significantly greater extent than bone from the rib and iliac crest regions (endochondral bone). However, the reason for this enhanced volume maintenance was not clarified for many years. On the basis of this enhanced volume maintenance, cranial bone became the ideal autogenous graft of choice for hard tissue repair. In the ensuing years, the current authors performed a large number of autogenous split skull cranial bone cranioplasties with significant success. However, the lure of an off-the-shelf material that obviates bone harvest remained. From 1995 to 2005, the senior author performed 20 full-thickness skull defect cranioplasty corrections using calcium phosphate cement (Norian Craniofacial Repair System; Synthes, Inc, West Chester, PA; Stryker-Leibinger, Kalamazoo, MI). Of these full-thickness defects, 16 were large (arbitrarily defined as greater than 25 cm2). In this paper, we report our long-term major and minor complication rates using this material. Because of our high, long-term complication rate (38%), we believe this material is contraindicated for large, full-thickness, skull defects (>25 cm2) and we have returned to autogenous cranial bone as the criterion standard for reconstruction in such patients.

RIA reamings and hip aspirate: a comparative evaluation of osteoprogenitor and endothelial progenitor cells.

Abstract: Autologous bone grafting represents the gold standard modality to treat atrophic non-unions by virtue of its osteoinductive and osteoconductive properties. The common harvest site is the iliac crest, but there are major concerns due to limited volume and considerable donor site morbidity. Alternative autologous bone graft can be harvested from the femoral bone cavity using a newly developed 'Reamer Irrigator Aspirator' (RIA). Osseous aspirated particles can be recovered with a filter and used as auto-graft. The purpose of this study was to compare the concentration and differentiation potential of mesenchymal stem cells (MSC) and endothelial progenitor cells (EPC) harvested with the RIA technique or from the iliac crest, respectively. RIA aspirate was collected from 26 patients undergoing intramedullary nailing of femur fractures. Iliac crest aspirate was collected from 38 patients undergoing bone graft transplantation. Concentration of MSC and EPC were assessed by means of the MSC colony assay, EPC culture assay and flowcytometry (CD34, CD133, VEGF-R2), respectively. Osteogenic differentiation of MSC's was measured by von Kossa staining. Patients in both groups did not significantly differ regarding their age, gender or pre-existing health conditions. In comparison to aspirates obtained from iliac crest the RIA aspirates from the femur contained a significantly higher percentage of CD34+ progenitor cells, a significantly higher concentration of MSC and a significantly higher concentration of early EPC. The percentage of late EPC did not differ between both sites. Moreover, the capability of MSC for calcium deposition was significantly enhanced in MSC obtained with RIA. Our results show that RIA aspirate is a rich source for different types of autologous progenitor cells, which can be used to accelerate healing of bone and other musculoskeletal tissues.

Mesenchymal stem cells and inorganic bovine bone mineral in sinus augmentation: comparison with augmentation by autologous bone in adult sheep.

Abstract: Our aim was to compare the osteogenic potential of mononuclear cells harvested from the iliac crest combined with bovine bone mineral (BBM) (experimental group) with that of autogenous cancellous bone alone (control group). We studied bilateral augmentations of the sinus floor in 6 adult sheep. BBM and mononuclear cells (MNC) were mixed and placed into one side and autogenous bone in the other side. Animals were killed after 8 and 16 weeks. Sites of augmentation were analysed radiographically and histologically. The mean (SD) augmentation volume was 3.0 (1.0) cm 3 and 2.7 (0.3) cm 3 after 8 and 16 weeks in the test group, and 2.8 (0.3) cm 3 (8 weeks) and 2.8 (1.2) cm 3 (16 weeks) in the control group, respectively. After 8 weeks, histomorphometric analysis showed 24 (3)% BBM, and 19 (11)% of newly formed bone in the test group. The control group had 20 (13%) of newly formed bone. Specimens after 16 weeks showed 29 (12%) of newly formed bone and 19 (3%) BBM in the test group. The amount of newly formed bone in the control group was 16 (6%). The results show that mononuclear cells, including mesenchymal stem cells, in combination with BBM as the biomaterial, have the potential to form bone.

Histological differences in iliac and tibial bone graft.

Abstract: Background: Cancellous bone graft is frequently used during orthopedic procedures. While the iliac crest has traditionally been the most common donor site, the proximal tibia is an alternative dono...

Efficacy of silicate-substituted calcium phosphate ceramic in posterolateral instrumented lumbar fusion.

Abstract: STUDY DESIGN/SETTING Retrospective review of a consecutive, nonrandomized series operated on by 2 surgeons. OBJECTIVE To evaluate the clinical and radiographic effectiveness of a silicated hydroxyapatite ceramic as a bone graft substitute in a series of patients undergoing posterolateral instrumented lumbar fusion. SUMMARY OF BACKGROUND DATA Newer-generation synthetic ceramics have been refined to maximize their host-graft interaction and stimulation of new tissue formation, including silicate-substitution. METHODS An independent radiologist interpreted the computed tomography images at 6, 12, and 24 months after surgery. Forty-two patients with 1- or 2-level lumbar degenerative disorders underwent posterior laminectomy (when indicated) and posterolateral fusion with instrumentation. Surgical levels included 15 patients who underwent 2-level and 27 single-level fusion procedures (57 levels operated on in total). RESULTS The average back pain scores improved from 5.6 ± 2.5 preoperative to 2.1 ± 2.5 at follow-up (P < 0.05). Similar results were seen with leg pain improvement from 5.8 ± 2.5 to 1.4 ± 1.9 (P < 0.05). At 6 months, 35% of levels revealed fusion, which increased to 76.2% and 76.5% at 12 and 24 months, respectively. No evidence of ectopic bone formation or osteolysis was noted. CONCLUSION In this study, a silicated calcium phosphate-based ceramic has been shown to be effective as a graft substitute and eliminate the need for autogenous iliac crest bone graft. The results confirm radiographic healing in posterolateral instrumented lumbar fusion at 24-months follow-up. The clinical outcomes also substantiate significant pain improvement consistent with published data in the literature compared with other bone graft alternatives.

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

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

A prospective, randomized, controlled, multicenter study of osteogenic protein-1 in instrumented posterolateral fusions: report on safety and feasibility.

Abstract: STUDY DESIGN A prospective, randomized, controlled, multicenter clinical study. OBJECTIVE To evaluate the safety and feasibility of osteogenic protein (OP)-1 in 1-level lumbar spine instrumented posterolateral fusions. SUMMARY OF BACKGROUND DATA Instrumented posterolateral fusion with the use of autograft is a commonly performed procedure for a variety of spinal disorders. However, harvesting of bone from the iliac crest is associated with complications. A promising alternative for autograft are bone morphogenetic proteins. METHODS As part of a larger prospective, randomized, multicenter study, 36 patients were included, who received a 1-level instrumented posterolateral fusion of the lumbar spine. All patients had a degenerative or isthmic spondylolisthesis with symptoms of neurologic compression. There were 2 treatment arms: OP-1 combined with locally available bone from laminectomy (OP-1 group) or iliac crest autograft (autograft group). The primary outcome was the fusion rate based on a computed tomography scan after 1-year follow-up. The clinical outcome was measured using the Oswestry Disability Index. Additionally, the safety of OP-1 was evaluated by comparing the number and severity of adverse events that occurred between both groups. RESULTS Using strict criteria, fusion rates of 63% were found in the OP-1 group and 67% in the control group (P = 0.95). There was a decrease in Oswestry scores at subsequent postoperative time points compared with preoperative values (P > 0.001). There were no significant differences in the mean Oswestry scores between the study group and control group at any time point (P = 0.56). No product-related adverse events occurred. CONCLUSION The results demonstrate that OP-1 combined with locally obtained autograft is a safe and effective alternative for iliac crest autograft in instrumented single-level posterolateral fusions of the lumbar spine. The main advantage of OP-1 is that it avoids morbidity associated with the harvesting of autogenous bone grafts from the iliac crest.