Metaphyseal Defects Research Articles

Knee joint reconstruction after hemiarticular resection using pedicled patella and vascularized fibular graft

Between 1999 and 2005, seven patients had resection of tumors around the knee joint that involved half of the articular surface of the femoral or tibial side. Average age of the patients was 28 years (range, 14-40). Tumor pathology was giant cell tumor in four patients, osteoblastoma in two, and benign fibrous histocytoma in one patient. Two patients had recurrent tumors. The tumor was located in the distal femur in five patients and in the proximal tibia in the remaining two. The ipsilateral patella pedicled on the infrapatellar fat pad was used to substitute the resected articular surface and a vascularized fibula osteoseptocutaneous flap was used to reconstruct the metaphyseal defect. Average follow-up period was 6.5 years (range, 3.5-10 years). All flaps survived. Average time to bone union was 3.5 months (range, 3-4 months), and average time to full weight-bearing was 5 months (range, 4-6 months). No radiological signs of avascular necrosis of the patella were observed in any patient. Two patients required secondary procedures for correction of instability. One patient had local recurrence. At final follow-up, the median range of knee motion was from 10° to 100°. The average Knee Society Score (KSS) was 76 points (range; 50-85 points), and the average KSS functional score was 76.6 points (range, 70-90 points). In conclusion, the procedure is a reliable option for after resection of tumors that involve half the articular surface of the femur or the tibia.

Fixation of Tibial plateau fractures with synthetic bone graft versus natural bone graft, a comparison study

Purpose The goal of this study was to determine differences in fracture stability and functional outcome between synthetic bone graft and natural bone graft with internal fixation of tibia plateau metaphyseal defects.

Low-Intensity Ultrasound Application in Distal Radius Metaphyseal Bone Defects of Dogs

We assessed the repair of transverse, 3-mm wide bone gaps created at the distal radius in 28 dogs that were randomly divided into two 14-animal groups; one was the control group and the other received a daily, 20-min application of low-intensity pulsed ultrasound for 100 days. Sequential radiographs, histomorphometrics, bone fluorescent histology and bone vascularity assessments found that all animals from both groups obtained a stage of hypertrophic-type nonunion with fibrocartilage tissue formation throughout the region of osteotomy. However, treated animals exhibited areas of endochondral ossification within the fibrocartilage region. There was no difference in type of vascularity or the newly formed bone process obtained by tetracycline labeling. Application of low-intensity ultrasound was not capable of significantly changing the reparative process and it may not be sufficiently powerful to overcome a combination of local deleterious effects on bone healing, created by gapping, excessive motion and periosteal resection. (E-mail: jbvolpon@fmrp.usp.br)

Fibrous cortical defect (nonossifying fibroma) of the mandibular ramus: report of 2 cases

Fibrous cortical defect, also known as metaphyseal fibrous defect and nonossifying fibroma, among other terms, is a benign, non-neoplastic proliferative process that is relatively common in the long bones of skeletally immature adolescents. Although the lesion is thought to be a developmental abnormality or defect, the exact etiopathogenesis is largely unknown. The lesion has a limited growth potential and good treatment outcome. This process is very rare in the gnathic bones, and only a few sporadic case reports are documented. This article presents the clinicopathologic features of 2 additional cases and reviews the relevant literature in attempt to identify key features and facilitate rendering definitive diagnosis for this rare entity.

Experimental posterolateral spinal fusion with beta tricalcium phosphate ceramic and bone marrow aspirate composite graft

Background:Beta tricalcium phosphate is commonly used in metaphyseal defects but its use in posterolateral spinal fusion remains controversial. There are very few published animal studies in which use of beta tricalcium phosphate has been evaluated in the posterolateral lumbar arthrodesis model. Hence we conducted a study to evaluate the potential of composite graft of beta tricalcium phosphate and bone marrow aspirate in comparison to autologous bone graft, when used for posterolateral spinal fusion.Materials and Methods:Single level posterolateral lumbar fusion was performed in 40 adult male Indian rabbits, which were assigned randomly into one of the four groups based on graft materials implanted; a) 3 gm beta tricalcium phosphate plus 3 ml bone marrow aspirate (Group I); b) 3 ml bone marrow aspirate alone (Group II); c) 3 gm beta tricalcium phosphate (Group III) and d) 3 gm autologous bone graft (Group IV). Each group had 10 rabbits. Half of the rabbits were sacrificed by injecting Phenobarbitone intraperitoneally after eight weeks and the remaining after 24 weeks, and were evaluated for fusion by X-rays, computed tomography (CT) scans, manual palpation test and histology.Results:Beta tricalcium phosphate used with bone marrow aspirate produced best results when compared to other groups (P =.0001). When beta tricalcium phosphate was used alone, fusion rates were better as compared to fusion achieved with autologous iliac crest bone graft though statistically not significant (P =0.07). Autologous bone graft showed signs of new bone formation. However, the rate of new bone formation was comparatively slow.Conclusion:Composite graft of beta tricalcium phosphate and bone marrow aspirate can be used as an alternative to autologous iliac crest bone graft.

Non-ossifying fibroma (metaphyseal fibrous defect) of the mandible

A 15-year-old young man was referred for evaluation of a non-tender swelling of the left mandibular angle region. A non-ossifying fibroma was diagnosed. The lesion was enucleated under general anesthesia. The postoperative course was uneventful. There have been no signs of recurrence, and there was complete bone regeneration in the region 24months after operation. This report also reviews other fifteen cases of non-ossifying fibroma in the mandible reported in the literature.

Platelet‐rich plasma on calcium phosphate granules promotes metaphyseal bone healing in mini‐pigs

The role of platelet-rich plasma (PRP) as a promoter of bone healing remains controversial. The aim of this study was to investigate the effect of PRP in combination with calcium phosphate granules (CPG) on bone defect healing in a metaphyseal long bone defect. A metaphyseal bone defect at the proximal tibia of 16 mini-pigs was filled with CPG combined with autologous PRP or CPG solely (control group). The PRP showed 4.4-fold more platelets compared to peripheral blood. Six weeks after surgery the radiological and histomorphometrical evaluations showed significantly more bone formation in the PRP group in the central area of the defect zone (p < 0.01) as well as the cortical defect zone (p < 0.04). Furthermore, the resorption rate of CPG was increased in animals who received PRP. Nevertheless there were only isolated instances of complete osseous bridging of the bone defects even in the PRP group. This study demonstrates that a PRP-CPG composit promotes bone regeneration but does not lead to a solid fusion of a tibial defect in mini-pigs.

Femorale Revisionsprothesen

Revision hip replacements are complicated surgeries because the femoral quality is often reduced by large substance losses. Stem fixation in terms of sufficient primary stability is therefore a great challenge for the orthopaedic surgeon. The aim of the present study was to examine two currently used prostheses in Germany (MHP and MRP) concerning their ability to securely bridge femoral defects. Up to a segmental metaphyseal defect, both stems showed sufficient fixation in our experimental setup. However, because of its predominantly distal fixation, the MRP stem would unnecessarily bridge proximal bone areas still capable of load bearing. In the presence of a transfemoral approach, the surgeon should favour the distal fixation mode because in this situation the proximal fixation option is absent. Therefore, the isthmus takes a key role for both stem designs.

Biofunctionality of MBCP ceramic granules (TricOs™) plus fibrin sealant (Tisseel®) versus MBCP ceramic granules as a filler of large periprosthetic bone defects: an investigative ovine study

We aimed to quantify bone colonization toward an untreated titanium implant with primary stability following filling of the defect with micromacroporous biphasic calcium phosphate (MBCP) granules (TricOs) or MBCP granules mixed with fibrin sealant (Tisseel). Medial arthrotomy was performed on the knees of 20 sheep to create a bone defect (16 mm deep; 10 mm diameter), followed by anchorage of a titanium screw. Defects were filled with TricOs or TricOs-Tisseel granules, a perforated MBCP washer, a titanium washer and titanium screw. Sheep were euthanized at 3, 6, 12 and 26 weeks. From Week 12 onwards, the percentage of bone in contact with the 8 mm anchorage part of the screw increased in both groups, confirming its primary stability. At 26 weeks, whereas bone colonization was similar in both groups, biodegradation of ceramic was more rapid in the TricOs-Tisseel group (P = 0.0422). The centripetal nature of bone colonization was evident. Bone contact with the titanium implant surface was negligible. In conclusion, the use of a model that reproduces a large metaphyseal bone defect around a titanium implant with primary stability, filled with a mixture of either TricOs ceramic granules or TricOs granules mixed with Tisseel fibrin sealant, suggests that the addition of fibrin to TricOs enhances bone filling surgical technology.

Letters

Department of Orthopaedic Surgery, The Medical College of Wisconsin, Milwaukee, WI (Toth) Department of Orthopaedic Surgery, Emory University School of Medicine, Atlanta, GA (Boden) The Hughston Clinic, Columbus, GA (Burkus) The comment refers to a sheep study (not a clinical study). The device is FDA approved, but not for the use in metaphyseal defects as described in the initial manuscript. Corporate/Industry funds were received in support of this work. One or more of the author(s) has/have received or will receive benefits for personal or professional use from a commerical party related directly or indirectly to the subject of this manuscript: e.g., honoraria, gift, consultancies, royalties, stocks, stock options, decision making position.

RhBMP-2 Induces Transient Bone Resorption Followed by Bone Formation in a Nonhuman Primate Core-Defect Model

Bone resorption preceding bone formation has been reported following the administration of recombinant human bone morphogenetic protein-2 (rhBMP-2) delivered in an absorbable collagen sponge (ACS) in metaphyseal bone. This study characterizes treatment with rhBMP-2/ACS in metaphyseal bone with use of a nonhuman primate core-defect model. Unilateral proximal femoral core defects were treated with 360 microg of rhBMP-2/ACS or ACS alone or were left untreated in seven, five, and five adult male cynomolgus monkeys, respectively. Distal femoral core defects in seven of the above animals were treated with 360 microg of rhBMP-2/ACS in one limb and ACS alone in the contralateral limb. Retention of rhBMP-2 in the proximal part of the femora was determined with use of tracer amounts of (125)I-rhBMP-2 imaged with a gamma camera. The distal part of the femora was evaluated with in vivo computed tomography. Computed tomography and histological evaluation were performed on harvested segments in all animals at twenty-four weeks. The histological response in the proximal and distal parts of the femora containing core defects treated with 360 microg of rhBMP-2/ACS in one limb and ACS alone in the contralateral limb was evaluated at one, two, and four weeks in three animals per time point. Approximately 39.9%, 24.2%, 3.4%, and 0.5% of the rhBMP-2 was retained in the proximal part of the femora at one, seven, fourteen, and twenty-one days, respectively. The mineral density and trabecular volume fraction of the core defects treated with rhBMP-2/ACS, those treated with ACS alone, and untreated core defects in the proximal part of the femora were 81%, 54%, and 20%, respectively, and 94%, 36%, and 31%, respectively, of the corresponding region in the contralateral limbs at twenty-four weeks. The mineral density and trabecular volume fraction of the region surrounding the core defects treated with rhBMP-2/ACS, those treated with ACS alone, and untreated core defects were 112%, 105%, and 104%, respectively, and 117%, 108%, and 107%, respectively, of the corresponding region in the contralateral limbs. Treatment with rhBMP-2/ACS increased the size of the proximal and distal core defects compared with treatment with ACS alone. Histological evaluation of the rhBMP-2/ACS-treated limbs demonstrated that bone resorption was initiated at one week in association with osteoclasts and receptor activator of nuclear factor-kappaB ligand-positive stained spindle-shaped cells and peaked at two weeks. Bone formation was observed at two weeks and was ongoing at twenty-four weeks. Treatment of metaphyseal core defects with rhBMP-2/ACS resulted in bone resorption followed by bone formation in nonhuman primates.

Combined use of platelet-rich plasma and autologous bone grafts in the treatment of long bone defects in mini-pigs

The use of platelet-rich plasma (PRP) for improving of bone defect healing is discussed controversially. The aim of this study was to assess the effect of PRP in combination with autologous cancellous graft on bone defect healing in a critical metaphyseal long bone defect. A critical size defect in the tibial metaphysis of 16 mini-pigs was filled either with autologous cancellous graft as control group or with autologous cancellous graft combined with autologous PRP. Compared to native blood platelets were enriched about 4.9-fold in the PRP. After 6 weeks, the specimens were assessed by X-ray and histological evaluation. Histomorphometrical analysis revealed that the area of new bone was significantly higher in the PRP group concerning the central area of the defect zone (p<0.02) as well as the cortical defect zone (p<0.01). All defects showed substantial new bone formation, but only defects of the PRP group regenerated entirely. The PRP group was superior to the control group even in the semi-quantitative assessment of the osseous bridging in both observed areas of the defect. Within the limits of the present study it could be demonstrated that PRP combined with autologous cancellous graft leads to a significantly better bone regeneration compared to isolated application of autologous cancellous graft in an in vivo critical size defect on load-bearing long bones of mini-pigs.

BENIGN FIBROUS HISTOCYTOMA OF THE DISTAL RADIUS: A REPORT OF A CASE AND A REVIEW OF THE LITERATURE

Benign fibrous histocytoma of bones is a very rare tumour and only a few cases have been reported. We report a case of 40-year-old patient with no significant previous medical history who presented with a painful lesion in his right wrist joint. Incision biopsy was done and there was a histological picture similar to a metaphyseal fibrous defect (non-ossifying fibroma). This was managed with excision of the lesion and filling the defect with cancellous and cortical bone grafts from the left iliac bone. To our knowledge, this is the second case report of a benign fibrous histocytoma involving the distal radius in adult. In this case report, we review similar cases in the literature and discuss the differential diagnoses of this lesion.

Behavior of bioactive glass-ceramic implanted into long bone defects: a scintigraphic study

The purpose of the study was to assess the long-term behavior and incorporation of the bioactive oxyhydroxyapatite glass-ceramic used to fill defects of long bones after curettage of bone cysts in 17 patients. The method of evaluation was a three-phase bone scintigraphy combined with radiographic and clinical evaluation. At a mean follow-up of 7 years, the glass-ceramic material had been completely incorporated. Mean uptake ratio was 1.31+/-0.25 after implantation of glass-ceramic in the metaphyseal region and 2.07+/-0.62 after implantation of glass-ceramic in the diaphyseal region (P<0.05). Mean uptake ratio was 1.40+/-0.30 in patients without persistent pain and 2.07+/-0.69 in patients who complained of pain in the area of synthetic filling (P<0.05). The bioactive glass-ceramic can be implanted into the metaphyseal defects of long bones, but this material is not suitable for filling the diaphyseal defects.

Evaluation of a novel nanocrystalline hydroxyapatite paste Ostim® in comparison to Alpha-BSM® - more bone ingrowth inside the implanted material with Ostim® compared to Alpha BSM®

BackgroundThe purpose of this study was to evaluate the performance a newly developed nanocrystalline hydroxyapatite, OSTIM® following functional implantation in femoral sites in thirty-eight sheep for 1, 2 or 3 months. Ostim® 35 was compared to an established calcium phosphate, Alpha BSM®.MethodsBiomechanical testing, μ-CT analysis, histological and histomorphological analyses were conducted to compare the treatments including evaluation of bone regeneration level, material degradation, implant biomechanical characteristics.ResultsThe micro-computed tomography (μCT) analysis and macroscopic observations showed that Ostim® seemed to diffuse easily particularly when the defects were created in a cancellous bone area. Alpha BSM® remained in the defect.The performance of Ostim was good in terms of mechanical properties that were similar to Alpha BSM® and the histological analysis showed that the bone regeneration was better with Ostim® than with Alpha BSM®. The histomorphometric analysis confirmed the qualitative analysis and showed more bone ingrowth inside the implanted material with Ostim® when compared to Alpha BSM ® at all time points.ConclusionsThe successful bone healing with osseous consolidation verifies the importance of the nanocrystalline hydroxyapatite in the treatment of metaphyseal osseous volume defects in the metaphyseal spongiosa.

Open reduction and internal fixation for treatment of severely impacted valgus proximal humeral fractures

Objective To assess the clinical results of open reduction and internal fixation(ORIF) for treatment of severely impacted valgus proximal humeral fractures. Methods From April 2004 to February 2008,twenty-three patients with a severely impacted valgus fractures of the proximal part of the humerus were treated with ORIF.The modified Thompson approach was employed to facilitate open reduction of the fractures and fixation with LPHP.Autologous bone graft was filled in the metaphyseal defect created behind the humeral head following its reduction in 20 cases.The rotator cuff tear was identified in 8 cases and was repaired with nonabsorbable sutures during the surgery.Systematic rehabilitation of the shoulder joint was performed postoperatively. Results All patients were followed up for at least one year,with an averaged of 17 months (ranged from 12 to 33 months).All fractures united within two years postoperatively.No patient had signs of internal fixation failure and avascular necrosis on the latest radiographys.The clinical outcomes were rated using Neer score system.Nine cases were graded as excellent,10 cases as good,3 cases as fair,and one as poor.The overall excellent and good rate was 82.6%.Patients' satisfactory rate was 91.3%.Pain at the iliac donor site was noted in 5 cases. Conclusion Treating severely impacted valgus proximal humeral fractures with open reduction and internal fixation using improved early motion of the shoulder and produced good clinical results. Key words: Humeral fractures; Internal fixators; Follow-up studies

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

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

A New Injectable Brushite Cement: First Results in Distal Radius and Proximal Tibia Fractures.

The restoration of metaphyseal defects remains a challenge for the treating surgeon. Although injectable brushite cements may help to refill bone defects stabilized with internal fixation, human data remains unavailable. The main goal of this prospective multicenter study was to observe the performance of this material in a clinical setting. The study conducted in seven trauma units included closed metaphyseal distal radius and proximal tibia fractures with bone defects, stabilized with internal fixation and subsequent filling with brushite cement. At 6- and 12-month follow-ups, patient satisfaction (visual analog scale [VAS]) was recorded, as well as complications. Thirty-eight proximal tibia fractures and 37 patients with distal radius fractures were included. Overall patient satisfaction with the treatment was high (mean VAS = 92 and 91 for proximal tibia and distal radius, respectively), despite the loss of reduction being described in 11% of proximal tibia and 24% of distal radius fractures; the majority of them included severe fracture types. Radiological evaluation showed postoperative cement leakage in 20 cases, where the majority occurred at the distal radius (n = 15). In 13 distal radius fractures, the leakage was resorbed by the final examination. The tested material showed good outcome in the majority of patients and adequate resorption characteristics, even in the case of extravasation. Stable internal fixation, sufficient bone quality, and no contact between the cement and joint are essential requirements for chronOS Inject, which can be considered as an alternative to existing augmentation materials.

Potential for thermal damage to articular cartilage by PMMA reconstruction of a bone cavity following tumor excision: A finite element study

Benign, giant cell tumors are often treated by intralesional excision and reconstruction with polymethylmethacrylate (PMMA) bone cement. The exothermic reaction of the in-situ polymerizing PMMA is believed to beneficially kill remaining tumor cells. However, at issue is the extent of this necrotic effect into the surrounding normal bone and the adjacent articular cartilage. Finite element analysis (ABAQUS 6.4-1) was used to determine the extent of possible thermal necrosis around prismatically shaped, PMMA implants (8–24 cc in volume), placed into a peripheral, sagittally symmetric, metaphyseal defect in the proximal tibia. Temperature/exposure time conditions indicating necrotic potential during the exotherm of the polymerizing bone cement were found in regions of the cancellous bone within 3 mm of the superior surface of the PMMA implant. If less than 3 mm of cancellous bone existed between the PMMA implant and the subchondral bone layer, regions of the subchondral bone were also exposed to thermally necrotic conditions. However, as long as there were at least 2 mm of uniform subchondral bone above the PMMA implant, the necrotic regions did not extend into the overlying articular cartilage. This was the case even when the PMMA was in direct contact with the subchondral bone. If the subchondral bone is not of sufficient thickness, or is not continuous, then care should be taken to protect the articular cartilage from thermal damage as a result of the reconstruction of the tumor cavity with PMMA bone cement.

Verwendung von nanokristallinem Hydroxyapatit (Ostim®) bei der Versorgung von Radiusfrakturen

In this study, innovative bone replacement material was tested after complicated metaphyseal radius fractures with the affected joints. In all, 11 C 2, 11 C 3 and 3 A 3 radius fractures were treated by surgery combining an angularly stable palmar plate osteosynthesis with defect filling using nanocrystalline hydroxyapatite. Examinations were conducted preoperatively and postoperatively after 4 weeks, 12 weeks and 9-12 months. After 10.5+/-1.4 months, inclination angles of 8.7+/-1.8 degrees (dorsopalmar) and 18.8+/-2.9 degrees (radioulnar) were measured at the treated fractures, the ulnar drift was 0.6+/-1.8 mm. According to the Gartland/Werley scale, 10 therapeutic results were considered "excellent", 12 "good" and 3 "fair". An angularly stable plate osteosynthesis with metaphyseal defect filling using nanocrystalline hydroxyapatite for the treatment of A 3, C 2 and C 3 radius fractures showed satisfactory radiological and clinical results.