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PubMed1987

Loss of proteoglycans during decalcification of fresh metaphyses with disodium ethylenediaminetetraacetate (EDTA).

Recent immunofluorescent and histochemical data did not detect changes in the concentration of proteoglycans between noncalcified and calcified cartilage in fetal bovine growth plate or metaphyseal bone. These findings were constant, regardless of prior fixation before demineralization with disodium ethylenediaminetetraacetate (EDTA) or prior demineralization before fixation. Previous experience has shown that EDTA can extract proteoglycans from calcified cartilage. With this in mind, we determined the amount of proteoglycan extracted from calcified cartilage in metaphyseal bone and uncalcified growth plate cartilages during decalcification of unfixed fresh tissues with EDTA. To this end, fresh growth plate cartilages and metaphyses were decalcified at 5 degrees C for 48 hours in a buffered solution of EDTA to which several protease inhibitors were added. Under these conditions 20-25% of the total proteoglycan (measured as uronic acid and hexosamine) was extracted from mineralized cartilage but only about 1% from the uncalcified (growth plate) cartilages. Thus, histochemical and immunohistochemical studies appear to be insensitive measures of proteoglycan concentrations in histological sections of mineralized tissue and may not give quantitative information.

Animals↗
PubMed2005

Treatment of epiphyseo-metaphyseal fractures in children with an original implant. The threaded pin with an adjustable lock (Fixano).

OBJECTIVE: Improvement of stability of internal fixation of epiphyseo-metaphyseal fractures in children with an implant characterized by its small diameter, easy utilization and its versatility. It avoids the drawbacks of screw fixation particularly in respect to the growth plate. INDICATIONS: Potentially all epiphyseo-metaphyseal fractures in children. CONTRAINDICATIONS: None. Crossing of the growth cartilage by small pins (< 2 mm) is without consequences under the condition that no compression is applied and that correction of a faulty pin position is limited to one. SURGICAL TECHNIQUE: In general, two threaded pins are used. They are inserted in a divergent fashion after the fracture has been reduced. Percutaneous insertion is possible. An adjustable lock screwed on a special key is slid over the end of the pin and put in contact with bone. It is squeezed until the key breaks off. The pins are then shortened. RESULTS: Since November 1999 these pins have been used for six olecranon fractures. In January 2002 we extended the indication to other fracture sites. Between January 2002 and July 2003 this system has been used 37 times (six olecranon fractures, eleven lateral condylar fractures and 13 medial epicondylar fractures of the elbow, and seven fractures of the ankle). A total of 43 fractures were treated (20 girls, 23 boys, average age 9.8 +/- 3.6 years) Average duration of follow-up 16.8 +/- 4.7 months. The assessment of results was based on technical, radiographic, and functional aspects. The overall results were good, in particular in respect to the stability of implants and the functional results. No secondary displacement, nor nonunion were observed; the pins were removed in all children at 6 weeks. The ease of handling the implants and the good clinical and radiologic results led us to propose these pins for routine use in epiphyseal and epiphyseo-metaphyseal fractures in children. Some improvements, however, are indicated principally, in particular in respect to the control of compression achieved by the adjustable lock.

Bone Nails↗
PubMed1998

[Distal, metaphyseal compression fractures of the radius. Results of open reposition, stable defect replacement with cortico-cancellous iliac crest bone and plate osteosynthesis].

Conservative treated distal radius fractures with extended metaphyseal void and missing cortical support resulted in loss of reduction. From 1988 till 1994 117 fractures of the distal radius were treated by open reduction, filling the metaphyseal void with a corticocancellous iliac bone graft and plate fixation. In this retrospective study results after surgical reconstruction were evaluated radiologically and clinically and were discussed to conservative treatment. 30 patients suffering from extraarticular metaphyseal distal radius fracture were evaluated after a mean of 42 months (minimum 20, maximum 68 months) after surgery. Ulnar variance was restored in 70% to the uninvolved side. Ulnar minus variance up to 2 mm persisted in 30%. Radial joint angles were restored to normal in 53%. In 40% of the patients a loss of reduction up to 10 degrees and in 7% up to 25 degrees occured. Active range of motion in the sagittal and frontal plane was equivalent to the non involved side in 30%. 70% of the patients showed reduced range of motion up to 20%. Rotation was unlimited in 77%, reduced up to 10% in 23%. Subjective results were excellent in 90%, good in 10%. Compared to conservative therapie, surgery showed superior results.

Adolescent↗
PubMed1996

Effect of essential trace metal on bone metabolism in the femoral-metaphyseal tissues of rats with skeletal unloading: comparison with zinc-chelating dipeptide.

The effect of essential trace metals on bone metabolism was investigated in the femoral-metaphyseal tissues obtained from skeletal-unloaded rats. Skeletal unloading was designed by using the model of hindlimb suspension in rats; the animals were fed for 4 days with the unloading. Femoral-metaphyseal tissues were cultured for 24 hours in a medium containing either vehicle (control), nickel, manganese, cobalt, copper, zinc, or zinc-chelating dipeptide (beta-alanyl-L-histidinato zinc; AHZ) in the concentration range of 10(-6) to 10(-4) M. Bone biochemical components (alkaline phosphatase activity, glucose consumption, and DNA content) were significantly decreased by skeletal unloading. The presence of zinc sulfate or AHZ (10(-5) and 10(-4) M) caused a significant increase of alkaline phosphatase activity in the bone tissues from unloaded rats. This effect was not seen by nickel, manganese, cobalt and copper (10(-6) to 10(-4) M). The culture medium glucose was clearly consumed by the bone tissues. This consumption was inhibited by nickel, manganese, or copper (10(-5) and 10(-4) M), while cobalt, zinc, and AHZ had no effect. DNA content in the bone tissues from unloaded rats was significantly increased by all metal compounds (10(-5) M). The effect of AHZ on bone components was greater than zinc sulfate. The AHZ (10(-5) M)-increased alkaline phosphatase activity in the bone tissues from unloaded rats was clearly blocked by the presence of cycloheximide (10(-6) M), staurosporine (10(-7) M), dibucaine (10(-4) M), or okadaic acid (10(-7) M). The present study demonstrates that, of various essential trace metals, zinc compounds have an unique anabolic effect on bone metabolism in the femoral-metaphyseal tissues of rats with skeletal unloading. Zinc-chelating dipeptide may stimulate bone protein synthesis through the mechanism that is involved in protein kinases.

Alkaline Phosphatase↗
PubMed2003

Spondylo-megaepiphyseal-metaphyseal dysplasia: an unusual bone dysplasia.

A rare case of spondylo-megaepiphyseal-metaphyseal dysplasia is reported in a 10-year-old boy. The features were metaphyseal dysplasia, markedly defective ossification of vertebral body centres and enlarged epiphyses. Although it shares some features with spondylo-metaphyseal dysplasia, oto-spondylo-megaepiphyseal dysplasia and cleidocranial dysplasia, the presence of several unusual radiological findings sets it apart.

Child↗
PubMed2000

Schmid type metaphyseal chondrodysplasia: a spondylometaphyseal dysplasia identical to the "Japanese" type.

BACKGROUND: Schmid-type metaphyseal chondrodysplasia (Schmid MCD) is an autosomal dominant chondrodysplasia resulting from various mutations in the COL10A1 gene. This disorder has been well delineated at a clinical level and has been classified radiographically as a pure metaphyseal chondrodysplasia. A missense mutation in the COL10A1 gene has also been shown to cause a rare spondylo-metaphyseal chondrodysplasia (SMD) named the "Japanese" type which, apart from exhibiting a mild spinal phenotype, shares striking clinical and radiographic similarities to Schmid MCD. OBJECTIVE: The clinical, radiographic and molecular similarities between Schmid MCD and Japanese SMD led to the hypothesis that these conditions could be identical type X collagenopathies. MATERIALS AND METHODS: We analyzed 33 cases of typical Schmid MCD from the International Skeletal Dysplasia Registry, looking specifically for any radiographic evidence of spinal involvement. RESULTS: We found that in 9.1% (3/33) of cases reviewed there was definite radiographic evidence of spinal involvement comprising mild platyspondyly, vertebral body abnormalities, and end-plate irregularity. CONCLUSION: These data indicate that spinal changes are an uncommon but variable component of Schmid MCD and that this condition and "Japanese" SMD are identical collagen type X disorders. Furthermore, the fact that the specific mutation reported in the family with Japanese type SMD, resulting in the substitution of a glutamic acid residue for a glycine at codon 595 (G595 E), has also been reported in a patient with Schmid MCD strongly supports this conclusion.

Child↗
PubMed2006

Parecoxib impairs early metaphyseal bone healing in rats.

INTRODUCTION: Cox2 inhibitors decrease prostaglandin production and therefore influence bone healing especially in unstable long bone models. It is unclear to what extent implant fixation in stable metaphyseal bone is impaired. METHOD: Male rats numbering 30 and female rats numbering 40 received a stainless steel screw in the metaphyseal bone of the proximal tibia. Half of the rats were treated with 6.4 mg/kg BW parecoxib by continuous release from a subcutaneous mini pump during 7 or 14 days. After treatment, the pull out force, stiffness, and pull out energy of the screw were measured. RESULTS: No effect of parecoxib on the pull out force was found for male rats. In female rats the pull out force was decreased by 16% (P = 0.03) after 7 days treatment with parecoxib. This effect had disappeared after 14 days. CONCLUSION: Adverse effects of parecoxib on the early phase healing of metaphyseal bone in female rats are small and were not detectable after 14 days. No effect was seen in male rats, possibly due to a faster metabolic elimination of the drug.

Animals↗
PubMed1999

Role of metaphyseal cancellous bone defect size in secondary displacement in Colles' fracture.

The purpose of this study was to evaluate the role of the metaphyseal cancellous bone defect size in secondary dislocation of Colles' fracture. Thirty-five patients with a dislocated Colles' fracture were examined by computed tomography (CT) for metaphyseal bone defects. The size of the defect was assessed and related to the surface area of the cross-section of the distal radius at the site of the defect. The relative size of the defect correlated with the severity of dorsal angulation of the fracture but not with the shortening of the radius seen after cast immobilization. We concluded that secondary displacement of the distal radius is partly mediated through the metaphyseal cancellous bone defect, and to prevent malunion in dorsal angulation, operative treatment or possibly filling of the defect should be considered even as early as during primary reduction if a large defect is suspected.

Adult↗
PubMed2000

Synergistic effect of genistein and zinc on bone components in the femoral-metaphyseal tissues of female rats.

The effect of genistein and zinc on bone components in rats was investigated. Femoral-metaphyseal tissues obtained from female rats (4 weeks old) were cultured for 24 h in a medium containing either vehicle or genistein (10(-7)-10(-5) M) in the absence or presence of zinc sulfate (10(-6)-10(-4) M) in vitro. The presence of genistein (10(-6) and 10(-5) M) or zinc (10(-6) and 10(-5) M) caused a significant increase in alkaline phosphatase activity, deoxyribonucleic acid (DNA), and calcium content in the metaphyseal tissues. These increases were significantly enhanced by the combination of each compound. The synergistic effect on bone components was seen in the combination with genistein (10(-6) and 10(-5) M) plus zinc (10(-5) M). Such an effect was completely blocked by the presence of cycloheximide (10(-6) M), an inhibitor of protein synthesis. Moreover, the oral administration of genistein (100 and 300 micrograms/kg body weight) or zinc sulfate (1 and 5 mg Zn/kg) to rats for 3 days caused a significant elevation of alkaline phosphatase activity, DNA, and calcium content in the femoral-metaphyseal tissues. These increases were significantly enhanced by the combination of each compound. The synergistic effect was seen in the case of genistein (100 and 300 micrograms/kg) plus zinc (5 mg/kg). These results demonstrate that the anabolic effect of genistein on bone components is synergistically enhanced by zinc in vitro and in vivo. This study further supports the view that the combination of nutritional factors has a potent anabolic effect on bone metabolism.

Alkaline Phosphatase↗
PubMed2002

Anabolic effect of phosphogenistein and phosphodaidzein on bone components in rat femoral-metaphyseal tissues in vitro.

The effect of phosphogenistein and phosphodaidzein, which are phosphorylated for the hydroxyl group (OH) at the 7-position of genistein and daidzein, on bone components was investigated. Femoral-metaphyseal tissues obtained from male rats (4 weeks old) were cultured for 24-72 h in Dulbecco's modified Eagle's medium (high glucose, 4.5%) supplemented with antibiotics and bovine serum albumin. The presence of phosphogenistein (10(-5) M) caused a significant increase in calcium content, alkaline phosphatase activity, and deoxyribonucleic acid (DNA) content in bone tissues cultured for 24 h. Phosphodaidzein (10(-5) M) significantly elevated bone calcium and DNA content. These effects were completely prevented by the presence of cycloheximide (10(-6) M), an inhibitor of protein synthesis. When femoral-metaphyseal tissues were cultured for 48 h in the presence of parathyroid hormone (1-34) (PTH; 10(-8) M) or prostaglandin E2 (PGE2; 10(-6) M), bone calcium content was significantly decreased. This decrease was significantly blocked by the presence of phosphogenistein (10(-6) and 10(-5) M) or phosphodaidzein (10(-6) and 10(-5) M). The presence of PTH (10(-8) M) or PGE2 (10(-6) M) caused a significant increase in glucose consumption and lactic acid production by bone tissues. These increases were significantly inhibited by the presence of phosphogenistein (10(-5) M) or phosphodaidzein (10(-5) M), indicating their inhibitory effect on bone resorption. The present study has demonstrated that both phosphogenistein and phosphodaidzein have an anabolic effect on bone metabolism in rat femoral-metaphyseal tissues in vitro.

Alkaline Phosphatase↗
PubMed1995

Metaphyseal bone lesions in young dogs with systemic canine distemper virus infection.

Bone lesions, restricted to the metaphyses of long bones, were observed in young dogs with systemic distemper following experimental and spontaneous infection. Canine distemper virus (CDV) antigen was found immunocytochemically in hematopoietic marrow cells, osteoclasts, osteoblasts and rarely in osteocytes. In experimentally infected dogs, viral antigen was demonstrated in the metaphysis between 5 and 36 days after infection. Associated lesions, characterized by necrosis of osteoclasts, persistence of primary spongiosa and atrophy and necrosis of osteoblasts and marrow cells, were mild and most prominent between 8 and 32 days postinfection. Metaphyseal osteosclerosis (MO) of the long bones, varying from mild to severe, was observed macroscopically in 8 (19%) out of 42 dogs with spontaneous distemper. Affected animals were between 3 and 6 months of age and belonged mainly to the large breeds. In these animals, MO was characterized histologically by persistence of primary spongiosa, loss of bone marrow cells and necrosis of osteoclasts and bone marrow cells varying from mild to severe. Summarized, CDV-associated bone lesions were only transient and there were no indications of viral persistence in bones of dogs experimentally infected with CDV. Although no clinical signs related to the bones were observed, the present study reveals that infection of metaphyseal bone cells is common in young dogs with systemic distemper and occurrence of viral antigen in these cells results in defects in bone modelling.

Animals↗
PubMed1987

The role of bone cells in increasing metaphyseal hard tissue in rapidly growing rats treated with prostaglandin E2.

The skeletal effects of graded doses of prostaglandin E2 (PGE2) given to weanling Sprague-Dawley rats for 3 weeks were investigated to elucidate the role of bone cells in increasing hard tissue mass. Decalcified (3 micron) sections were quantified in the light microscope by point hit and intersect counting using a Merz grid. Hard tissue mass (bone and calcified cartilage) and osteoblast, osteoclast and osteoprogenitor cell numbers were counted in metaphyseal tissue bands 0.24, 0.48, 0.72, 1.20, 1.68, 2.16, 2.64, 3.12, 3.60 and 4.08 mm from the growth plate metaphyseal junction. Changes were different and more marked in the secondary spongiosa than the primary spongiosa of the proximal tibial metaphysis of treated rats. In the primary spongiosa of rats treated with 3 or 6 mg PGE2/kg/d (1) an increase in bone and hard tissue masses and (2) a decrease in osteoclasts, osteoprogenitor cell numbers and surface to volume ratio was observed. In the secondary spongiosa (lower metaphysis) of rats treated with 2 same dose levels (1) an increase in bone mass, calcified cartilage cores, and hard tissue mass and perimeter, an elevation of osteoprogenitor cell and osteoblast numbers, a depression of osteoclast, osteoclast nuclei numbers and surface to volume ratio and new sites of intramembranous ossification (woven bone formation) originating from the cortico-endosteal envelope was observed. In this growing rat skeletal model, we showed that PGE2 increases metaphyseal calcified tissue mass by depressing hard tissue resorption and stimulating the replication and differentiation of osteoblast precursors to form new foci of woven bone.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Adaptation of non-growing former epiphysis and metaphyseal trabecular bones to aging and immobilization in rat.

No data exit for distal tibia (DT), a bone site with growth plate closure at 3 months of age and with very low trabecular bone turnover rate. The purpose of this study was to characterize the response of DT to aging and immobilization (IM) in 6 to 16.5 month-old female rats. One hundred and forty six 6 month-old Sprague-Dawley rats were divided into aging controls and right hindlimb immobilization (RHLI) groups. The right hindlimb was immobilized against the abdomen with elastic bandages. Rats were sacrificed serially from 6 to 16.5 months old at intervals of 2 to 8 weeks. The histomorphometric study was performed on areas of former epiphyseal and metaphyseal trabecular bone of DT. No changes on bone mass or architecture were found in aging controls throughout the study. There was a decrease in bone mass of the former epiphysis after 3.5 months of IM due to resorption exceeding formation. Then it reverted to the aging control level at 4 months post IM. At the former metaphyseal site, significant bone loss (-19%) was observed as early as two weeks after IM. The peak bone loss (-54%) was reached at 1.5 months after IM and plateaued thereafter. The bone loss was mainly due to the reduction of trabecular thickness although trabecular number decreased significantly after 3.5 months IM. These results suggest that both former epiphysis and metaphyseal trabecular bones in DT can quickly adapt by losing bone to immobilization.

Adaptation, Physiological↗
PubMed2004

Histochemical evaluation for the biological effect of menatetrenone on metaphyseal trabeculae of ovariectomized rats.

To evaluate the biological effects of vitamin K2 (menatetrenone, MK-4) on ovariectomy (OVX)-induced bone loss, we have examined histological alterations of femoral metaphyses of sham-operated (sham group), ovariectomized (OVX group), and MK-4 dietary-supplemented OVX (MK-4 group; 50 mg/kg per day) female Fischer rats 1, 2, 5, and 8 weeks after OVX. In the first week, rats of the OVX and MK-4 groups showed discontinuous trabeculae compared with sham-operated rats. At 2 weeks after OVX, the OVX rats revealed many large tartrate resistant acid phosphatase (TRAP)-positive osteoclasts, while osteoclasts in the MK-4-treated rats were similar in size to those of the sham group. At 5 weeks, the OVX and MK-4 groups revealed fragmented trabeculae in femoral metaphyses. The cartilage matrix was partially exposed due to stimulated bone resorption in the OVX group, but not in the MK-4 group. After 8 weeks, the OVX rats had little metaphyseal trabeculae, whereas the MK-4-treated rats had maintained short trabeculae. Despite the presence of intense alkaline phosphatase-positive osteoblasts on trabeculae in the MK-4 group, TRAP-positive osteoclasts were flattened without developing ruffled borders. Therefore, MK-4 appeared to lessen the increase in osteoclastic bone resorption induced by OVX, as well as to maintain the accelerated osteoblastic activity. It is of importance to identify the target cells for MK-4 in bone. Autoradiography localized [3H]-labeled MK-4 mainly in osteoblasts and adjacent bone matrices, but not in osteoclasts, indicating that MK-4 targets osteoblasts. Thus, MK-4 appears to target osteoblasts, consequently inhibiting bone loss induced by ovariectomy.

Animals↗
PubMed2005

Interlocking nails for displaced metaphyseal fractures of the distal tibia.

Metaphyseal fractures of the distal tibia near the ankle joint are difficult to manage. Poor soft tissue coverage and comminution of the fracture complicate open reduction. This prospective study aims to evaluate the practicability of using interlocking nails to treat such fractures. Using the method of closed reduction and internal fixation with a shortened tibial interlocking nail, 20 consecutive cases of distal tibial metaphyseal fractures within 4 cm of the ankle joint line were enrolled from 1997 to 2001. All patients received regular post-operative radiographic check-up and the ankle function was evaluated with the Iowa Ankle-Evaluation rating system. Our result was satisfactory and all of the fractures united solidly with a mean union time of 17.2 weeks. No major complication occurred. We conclude that tibial interlocking nailing is a reliable and safe method for managing metaphyseal fractures of the distal tibia near the ankle joint.

Adult↗
PubMed1986

The role of the epiphyseal and metaphyseal circulations on longitudinal growth in the dog: an experimental study.

An experimental model using the immature canine proximal fibular epiphysis was developed to isolate and investigate the effects of the epiphyseal and metaphyseal circulations on longitudinal growth. Experimental constructs studied the epiphyseal circulation, the epiphyseal and metaphyseal circulations, a devascularized growth plate, and a control group. Twenty-four limbs were studied by serial x-ray films and microangiographic and histologic analyses at time of death, 24 weeks after surgery. The data from this preliminary study show that both metaphyseal and epiphyseal circulations are necessary for predictable longitudinal growth.

Animals↗
PubMed2001

The surgical treatment of Kienböck's disease by radius and ulna metaphyseal core decompression.

We present a new surgical procedure, metaphyseal core decompression, to treat Kienböck's disease. Twenty-two patients were treated between 1976 and 1988 and were retrospectively reviewed. Sixteen were male and 6 female with an average age of 36 years (range, 18-64 years). The surgical technique involved curettage of the distal radius and ulna metaphyseal bone through small cortical windows. The average follow-up period was 10 years (range, 6-16 years). No postoperative complications were noted and no patient underwent additional surgical procedure. Sixteen patients were pain-free; 4 noted occasional pain. Twenty returned to their prior occupation. One patient had moderate pain and altered his occupation. Another had increasing pain and had x-ray evidence of advanced intercarpal arthritis. The average arc of wrist extension and flexion was 77% of the opposite wrist and the average grip strength was 75%. Long-term follow-up monitoring indicates that the metaphyseal core decompression produces results at least as good as other surgical procedures without any postoperative complications.

Adult↗