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At least 235 records · Page 13Linked to original sources
PubMed1997

Jansen-type metaphyseal chondrodysplasia: analysis of PTH/PTH-related protein receptor messenger RNA by the reverse transcriptase-polymerase chain method.

Jansen-type metaphyseal chondrodysplasia (JMC) has both delayed ossification in long bones and usually hypercalcemia. We report a Japanese male patient with JMC who presented with rachitic signs on radiographs, hypercalcemia (13 mg/dl) and low %TRP at age 3 months (mo). Hypercalcemia was treated from age 3 mo to 11 yr. Progressive widening, splaying and fragmentation of the metaphyses have been recognized on radiographs which resulted in shortened tubular bones and consequent short stature [107 cm (-6.5 SD)] at age 13 yr. Hypercalcemia tended to normalize, and %TRP became normal at age 13 yr. Repeated measurements of serum PTH and PTH-related protein (PTHrP) levels showed that they were low or normal in the face of hypercalcemia and high urine cAMP excretion, which led us to suspect constitutive activation of the PTH/PTHrP receptor. Direct sequencing of PTH/PTHrP receptor complementary DNA from skin fibroblast cells revealed a CAC to CGC transversion yielding a strictly conserved His223 to Arg substitution found in 90% of DNA fragment in the second transmembrane domain of the receptor. This mutation created a restriction site Sphl (G/CATG/C). Direct sequencing of genomic DNA and also restriction enzyme digestion revealed heterozygous transition. The mutation was absent in the parents with normal phenotype. We conclude that both dysplastic bone lesions and calcium homeostasis are age-dependent in JMC, and that the His223-Arg substitution is the same as that found in four Caucasian patients with a similar phenotype irrespective of the ethnic difference, and that the preferential expression of an abnormal allele of the PTH/PTHrP receptor mRNA in skin fibroblast despite heterogygotic transversion in the genomic DNA suggests the importance of allele expression.

Dwarfism↗
PubMed1995

Relationship of the subperiosteal bone collar to metaphyseal lesions in abused infants.

We studied the relationship between the subperiosteal bone collar and forty metaphyseal lesions in specimens obtained at autopsy from ten infants who died with evidence of abuse. The fracture specimens were studied with high-detail radiography and light microscopy. The typical morphological pattern was a fracture extending through the primary spongiosa adjacent to the chondro-osseous junction. As the fracture line approached the cortex, it veered away from the growth plate, undercutting a fragment of bone that was thicker peripherally than it was centrally. Histological examination showed that this peripheral fragment of bone included the subperiosteal bone collar. Inclusion of the subperiosteal bone collar within the peripheral portion of the metaphyseal fracture fragment explains the radiographic appearance of corner fractures and bucket-handle patterns described by Caffey in abused infants.

Bone Marrow↗
PubMed1998

Epiphyseal-metaphyseal enchondromatosis. A new clinical entity.

We reviewed the cases of eight unrelated children who had an unusual form of enchondromatosis characterized by unilateral enchondromas arising within the epiphyseal and metaphyseal regions of the long tubular bones of the lower extremity. Unlike previously described enchondromas, the lesions developed extensively within the epiphysis before closure of the growth plate and there was direct extension across the epiphyseal growth plate into the metaphysis. The lesions resulted in severe limb-length discrepancy and angular deformity (which increased in every patient after the time of presentation), asymmetrical premature physeal arrest, and joint incongruity, all of which necessitated numerous operative procedures. Seven patients had limb-lengthening and one had a Boyd amputation without lengthening. Five patients had a second lengthening procedure. Twenty-seven osteotomies (range, one to five procedures per patient) were done; six patients had a repeat osteotomy. Four patients had an epiphyseodesis. We believe that these lesions represent a previously undescribed clinical entity, which we termed epiphyseal-metaphyseal enchondromatosis.

Biopsy↗
PubMed2003

Humeral fixation by press-fitting of a tapered metaphyseal stem: a prospective radiographic study.

BACKGROUND: The technique of shoulder arthroplasty requires a method for securely and durably fixing the humeral component in the medullary canal of the proximal part of the humerus. As an alternative to fixation by cementing or tissue ingrowth, we explored the effectiveness of using a prosthesis with a metaphyseal taper from the anatomic neck to the diaphysis. This component is designed to obtain press-fit fixation in the cancellous bone of the metaphysis rather than in the cortical bone of the diaphysis. We tested the hypothesis that this press-fit humeral stem, designed to respect the taper of the proximal part of the humeral canal, would be associated with a low rate of loosening in patients managed with primary shoulder arthroplasty for osteoarthritis. METHODS: A prospective study was conducted to evaluate the prevalence of radiolucent lines around press-fit humeral prostheses. One hundred and thirty-one patients with glenohumeral osteoarthritis were followed for a minimum of two years. A zonal method of evaluating radiolucent lines was established. Shift in position and subsidence were judged qualitatively. RESULTS: No component showed subsidence or a shift in position. Fifty shoulders (39%) had no radiolucency. Two shoulders had radiolucency around the proximal part of the prosthesis, and seventy-five had radiolucency at the distal tip. Eleven radiolucencies were > or =1 mm in width. A neutral stem orientation was significantly less likely to be associated with radiolucency (p = 0.026). The prevalence of radiolucent lines did not differ between patients managed with hemiarthroplasty and those managed with total shoulder arthroplasty, and it did not increase with longer periods of follow-up. CONCLUSIONS: In patients managed with shoulder arthroplasty, the fixation of a press-fit humeral component that has a tapered metaphyseal segment is comparable with that reported for cemented components and superior to that reported for press-fit cylindrical components. CLINICAL RELEVANCE: This type of fixation may provide an alternative to cementing of the humeral stem in individuals with glenohumeral osteoarthritis.

Adult↗
PubMed2005

Intramedullary nailing of distal metaphyseal tibial fractures.

BACKGROUND: The treatment of distal metaphyseal tibial fractures remains controversial. This study was performed to evaluate the results of intramedullary nailing of distal tibial fractures located within 5 cm of the ankle joint. METHODS: Over a sixteen-month period at two institutions, thirty-six tibial fractures that involved the distal 5 cm of the tibia were treated with reamed intramedullary nailing with use of either two or three distal interlocking screws. Ten fractures with articular extension were treated with supplementary screw fixation prior to the intramedullary nailing. Radiographs were reviewed to determine the immediate and final alignments and fracture-healing. The Short Form-36 (SF-36) and Musculoskeletal Function Assessment (MFA) questionnaires were used to evaluate functional outcome. RESULTS: Acceptable radiographic alignment, defined as <5 degrees of angulation in any plane, was obtained in thirty-three patients (92%). No patient had any change in alignment between the immediate postoperative and the final radiographic evaluation. Complications included one deep infection and one iatrogenic fracture at the time of the intramedullary nailing. Six patients could not be followed. The remaining thirty fractures united at an average of 23.5 weeks. Three patients with associated traumatic bone loss underwent a staged autograft procedure, and they had fracture-healing at an average of 44.3 weeks. The functional outcome was determined at a minimum of one year for nineteen patients and at a minimum of two years (average, 4.5 years) for fifteen patients. At one year, there were significant limitations in several domains despite fracture union and maintenance of alignment, but there was improvement in the MFA scores with time. CONCLUSIONS: Intramedullary nailing is an effective alternative for the treatment of distal metaphyseal tibial fractures. Simple articular extension of the fracture is not a contraindication to intramedullary fixation. Functional outcomes improve with time.

Adolescent↗
PubMed2005

Use of a distraction plate for distal radial fractures with metaphyseal and diaphyseal comminution.

BACKGROUND: Distal radial fractures with extensive comminution involving the metaphyseal-diaphyseal junction present a major treatment dilemma. Of particular difficulty are those fractures involving the articular surface. One approach is to apply a dorsal 3.5-mm plate extra-articularly from the radius to the third metacarpal, stabilizing the diaphysis and maintaining distraction across the radiocarpal joint. METHODS: Twenty-two patients treated with a distraction plate for a comminuted distal radial fracture were included in the study. With use of three limited incisions, a 3.5-mm ASIF plate was applied in distraction dorsally from the radial diaphysis, bypassing the comminuted segment, to the long-finger metacarpal, where it was fixed distally. The articular surface was anatomically reduced and was secured with Kirschner wires or screws. Eleven of the twenty-two fractures were treated with bone-grafting. The plate was removed after fracture consolidation (at an average of 124 days), and wrist motion was initiated. All patients were followed prospectively with use of radiographs, physical examination, and DASH (Disabilities of the Arm, Shoulder and Hand) scores. RESULTS: All fractures united by an average of 110 days. Radiographs showed an average palmar tilt of 4.6 degrees and an average ulnar variance of neutral (0 degrees), whereas loss of radial length averaged 2 mm. Flexion and extension averaged 57 degrees and 65 degrees, respectively, and pronation and supination averaged 77 degrees and 76 degrees , respectively. The average DASH scores were 34 points at six months, 15 points at one year, and 11.5 points at the time of final follow-up (at an average of 24.8 months). According to the Gartland-Werley rating system, fourteen patients had an excellent result, six had a good result, and two had a fair result. Grip strength and the range of motion of the wrist at one year correlated inversely with the proximal extent of fracture comminution into the diaphysis. The duration of plate immobilization did not correlate with the range of motion of the wrist or with the DASH score at one year. CONCLUSIONS: The use of a distraction plate combined with reduction of the articular surface and bone-grafting when needed can be an effective technique for treatment of fractures of the distal end of the radius with extensive metaphyseal and diaphyseal comminution. A functional range of motion with minimal disability can be achieved despite a prolonged period of fixation with a distraction plate across the wrist joint.

Adult↗
PubMed2006

Use of a distraction plate for distal radial fractures with metaphyseal and diaphyseal comminution. Surgical technique.

BACKGROUND: Distal radial fractures with extensive comminution involving the metaphyseal-diaphyseal junction present a major treatment dilemma. Of particular difficulty are those fractures involving the articular surface. One approach is to apply a dorsal 3.5-mm plate extra-articularly from the radius to the third metacarpal, stabilizing the diaphysis and maintaining distraction across the radiocarpal joint. METHODS: Twenty-two patients treated with a distraction plate for a comminuted distal radial fracture were included in the study. With use of three limited incisions, a 3.5-mm ASIF plate was applied in distraction dorsally from the radial diaphysis, bypassing the comminuted segment, to the long-finger metacarpal, where it was fixed distally. The articular surface was anatomically reduced and was secured with Kirschner wires or screws. Eleven of the twenty-two fractures were treated with bone-grafting. The plate was removed after fracture consolidation (at an average of 124 days), and wrist motion was initiated. All patients were followed prospectively with use of radiographs, physical examination, and DASH (Disabilities of the Arm, Shoulder and Hand) scores. RESULTS: All fractures united by an average of 110 days. Radiographs showed an average palmar tilt of 4.6 degrees and an average ulnar variance of neutral (0 degrees), whereas loss of radial length averaged 2 mm. Flexion and extension averaged 57 degrees and 65 degrees, respectively, and pronation and supination averaged 77 degrees and 76 degrees, respectively. The average DASH scores were 34 points at six months, 15 points at one year, and 11.5 points at the time of final follow-up (at an average of 24.8 months). According to the Gartland-Werley rating system, fourteen patients had an excellent result, six had a good result, and two had a fair result. Grip strength and the range of motion of the wrist at one year correlated inversely with the proximal extent of fracture comminution into the diaphysis. The duration of plate immobilization did not correlate with the range of motion of the wrist or with the DASH score at one year. CONCLUSIONS: The use of a distraction plate combined with reduction of the articular surface and bone-grafting when needed can be an effective technique for treatment of fractures of the distal end of the radius with extensive metaphyseal and diaphyseal comminution. A functional range of motion with minimal disability can be achieved despite a prolonged period of fixation with a distraction plate across the wrist joint.

Bone Plates↗
PubMed1993

Metaphyseal abnormalities in children: pathophysiology and radiologic appearance.

The most active site of formation of bone in children is the metaphysis. Systemic and local diseases are reflected by alterations in the morphology of this region. In this pictorial essay, we examine several patterns of metaphyseal abnormalities seen on radiologic images and review the associated pathophysiology. Differential diagnosis may be aided by considering the pathologic mechanisms responsible for the various metaphyseal alterations.

Adolescent↗
PubMed2000

In vitro comparison of metaphyseal and diaphyseal placement of centrally threaded, positive-profile transfixation pins in the equine third metacarpal bone.

OBJECTIVE: To evaluate in vitro holding power and associated microstructural and thermal damage from placement of positive-profile transfixation pins in the diaphysis and metaphysis of the equine third metacarpal bone. SAMPLE POPULATION: Third metacarpal bones from 30 pairs of adult equine cadavers. PROCEDURE: Centrally threaded positive-profile transfixation pins were placed in the diaphysis of 1 metacarpal bone and the metaphysis of the opposite metacarpal bone of 15 pairs of bones. Tensile force at failure for axial extraction was measured with a materials testing system. An additional 15 pairs of metacarpal bones were tested similarly following cyclic loading. Microstructural damage was evaluated via scanning electron microscopy in another 6 pairs of metacarpal bones, 2 pairs in each of the following 3 groups: metacarpal bones with tapped holes and without transfixation pin placement, metacarpal bones following transfixation pin placement, and metacarpal bones following transfixation pin placement and cyclic loading. Temperature of the hardware was measured with a surface thermocouple in 12 additional metacarpal bones warmed to 38 C. RESULTS: The diaphysis provided significantly greater resistance to axial extraction than the metaphysis. There were no significant temperature differences between diaphyseal and metaphyseal placement. Microstructural damage was limited to occasional microfractures seen only in cortical bone of diaphyseal and metaphyseal locations. Microfractures originated during drilling and tapping but did not worsen following transfixation pin placement or cyclic loading. CONCLUSIONS AND CLINICAL RELEVANCE: Centrally threaded, positive-profile transfixation pins have greater resistance to axial extraction in the diaphysis than in the metaphysis of equine third metacarpal bone in vitro. This information may be used to create more stable external skeletal fixation in horses with fractures.

Animals↗
PubMed1984

Mineralization in rat metaphyseal bone exhibits a circadian stage dependency.

Density gradient fractionation analysis of rat metaphyseal bone was used to delineate the biorhythmic changes in bone matrix mineralization. Seventy-two 4-week-old rats were entrained to 12-hr light, 12-hr dark cycles (light, 0800-2000 hr; darkness, 2000-0800 hr) for 4 weeks. All animals were fed ad lib. on Purina laboratory rat chow and tap water. Groups of 10-12 rats were killed by cervical dislocation at 4-hr intervals during a 24-hr period, and the tibias were then biopsied and frozen in liquid N2. Metaphyseal bone was fractionated via bromoformtoluene density gradients into specific gravity fractions ranging from 1.7 to 2.8. Density gradient fractions were analyzed for concentrations of calcium and inorganic phosphorus. Chronograms indicated that the accumulation of both calcium and inorganic phosphorus into the newly forming/least-dense mineral moieties of bone (1.3-1.7 sp grav) showed a single peak in the biorhythm of the rat. A statistically significant circadian rhythm of mineralization was detected for calcium (P less than 0.001) and inorganic phosphorus (P less than 0.039), with peaks during the environmental dark span. These results suggest that the physiological phasing of bone mineralization in the light-dark synchronized rat, is similar to that previously noted for cartilage mineralization and is antiphasal to the midday peak in bone collagen synthesis.

Animals↗
PubMed2004

The use of an injectable bone graft substitute in tibial metaphyseal fractures.

Eight consecutive patients with severely comminuted proximal or distal tibial metaphyseal fractures were surgically treated with a novel injectable, in situ hardening calcium sulfate material to provide temporary intraoperative structural support until instrumentation was appropriately placed. The calcium sulfate bone substitute was also used as a bone void filler to provide an osteoconductive environment following stabilization. Bone regrowth was observed in all patients and, in seven of the eight patients, 90%-100% bone formation was observed within 3 months. The bone substitute had almost completely resorbed by 3 months in all patients. One patient with extensive initial bone loss required a second bone graft. Although the patient sample size was small, the success rate of treating severely comminuted fractures was significantly better than in reports using only internal fixation. Injectable bone substitute for minimally invasive surgery to repair metaphyseal fractures.

Adult↗
PubMed1999

[Metaphyseal chondrodysplasia].

Metaphyseal chondrodysplasia (MCD) is a heterogeneous group of diseases characterised by defective enchondral ossification, leading to metaphyseal changes. The different types of MCD can be distinguished by clinical findings, radiology and genetic tests. Based on a case story with MCD, pancreatic insufficiency and granulocytopenia (Shwachman's syndrome), we review the most common types of MCD with regard to clinical manifestations, radiological findings, and genetic background.

Adolescent↗
PubMedDate not supplied

Smooth Kirschner (K) wire fixation of distal metaphyseal osteotomy bunionectomies: a 10-year retrospective survey.

The authors reviewed 500 distal metaphyseal osteotomy bunionectomies with smooth Kirschner (K)-wire fixation performed over a 10-year period. Postoperatively, the patients were allowed to ambulate with a forefoot compression bandage and a semirigid surgical shoe. The cases were evaluated radiographically for malunion, delayed union, nonunion, aseptic necrosis, bone callus formation, and final alignment. Soft tissue and bone infection, as well as pin irritation, were also evaluated. Computation of results demonstrated eight malunions, one delayed union, no nonunions, and two cases of aseptic necrosis. There were 52 cases (10.4%) that led to bone callus formation; 54 patients (10.8%) experienced pin irritation. A total of seven infections occurred (1.4%) that could possibly be attributed to the pin, of which four (0.8%) required incision and drainage. It was observed that certain procedures, such as the Laird osteotomy, decreased the effectiveness of the K-wire, while others, such as the Chevron osteotomy, resulted in the fewest complications. Bunionectomies performed bilaterally or with adjunct procedures, in contrast to isolated bunionectomies, were also found to decrease the effectiveness of the K-wire. Due to the minimal number of complications that were encountered and the high success rate that was attained, the authors conclude that utilization of smooth K-wire fixation for distal metaphyseal osteotomy bunionectomies remains a viable and effective treatment alternative.

Adolescent↗
PubMedDate not supplied

Increased osteogenic response to exercise in metaphyseal versus diaphyseal cortical bone.

Recent experimental data suggest that the anabolic response of bone to changes in physical activity and mechanical loading may vary among different skeletal elements, and even within different regions of the same bone. In order to better understand site-specific variation in bone modeling we used an experimental protocol in which locomotor activity was increased in laboratory mice with regular treadmill exercise for only 30 min/day. We predicted that the regular muscle contractions that occur during exercise would significantly increase cortical bone formation in these animals, and that the increase in cortical bone mass would vary between metaphyseal and diaphyseal regions. Cortical bone mass, density, and bone geometry were compared between these two regions using pQCT technology. Results indicate that exercise increases bone mineral content (BMC) in the mid-diaphysis by approximately 20%, whereas bone mass in the metaphyseal region is increased by approximately 35%. Endosteal and periosteal circumference at the midshaft are increased with exercise, whereas increased periosteal circumference is accompanied by marked endosteal contraction at the metaphysis, resulting in an increase in cortical area of more than 50%. These findings suggest that the osteogenic response of cortical bone to exercise varies significantly along the length of a bone, and more distal regions appear most likely to exhibit morphologic changes when loading conditions are altered.

Animals↗
PubMed1991

Locked intramedullary fixation for metaphyseal malunion and nonunion.

Locked intramedullary rod fixation, established for metaphyseal fractures, is applicable to reconstructive procedures. Fourteen cases of complex nonunion or malunion (five infected) were reviewed retrospectively. Thirteen of the 14 fractures united. Eleven of 14 required an open procedure for removal of metal, soft-tissue release, bone grafting, osteotomy, or resection of infected bone. Infections were controlled by resection, depot antibiotics, and early stabilization. Interlocking intramedullary rods are an excellent fixation technique for posttraumatic metaphyseal reconstructive procedures.

Adolescent↗
PubMed1990

Medial external fixation with lateral plate internal fixation in metaphyseal tibia fractures. A report of eight cases associated with severe soft-tissue injury.

Eight patients with unstable fractures involving the articular surface and metaphyseal-diaphyseal bone of the proximal or distal tibia associated with severe soft-tissue injury or compounding wound were treated with irrigation, debridement, tetanus inoculation, antibiotic prophylaxis, and combined internal fixation with one-half frame external skeletal fixation for neutralization. All patients were followed to complete healing and functional restoration of the extremity. All fractures healed, but one superficial and one deep infection occurred. All patients achieved at least 110 degrees of knee motion. This method should be considered in unstable metaphyseal and articular tibia fractures not adequately stabilized with a lateral plate in which use of an additional medial plate is required for stability, but contraindicated because of the status of the soft tissues or extensive comminution of the bone.

Accidents, Traffic↗
PubMedDate not supplied

Tailor's bunion: clinical evaluation and correction by distal metaphyseal osteotomy with cortical screw fixation.

Fifth metatarsal distal metaphyseal osteotomy represents a very common surgical procedure performed for tailor's bunion deformity. The authors advocate using a cortical bone screw for fixation device offers many advantages over conventional devices (i.e., Kirschner wire). The purpose of this paper is to offer a means to thoroughly evaluate tailor's bunion deformity clinically, biomechanically, and radiographically. This will allow the podiatric surgeon to choose a procedure of choice to correct the deformity. The technique of fifth metatarsal distal metaphyseal osteotomy with cortical bone screw fixation using AO4 principles is fully described.

Biomechanical Phenomena↗
PubMedDate not supplied

Effect of long-term nontraumatic immobilization on metaphyseal spongiosa in young adult and old beagle dogs.

A radiographic and histomorphometric change in volume in the metaphyseal spongiosa in response to long-term immobilization was investigated in young adult and old beagle dogs and compared with changes in diaphyseal compacta of the same bones. Sixty weeks of nontraumatic immobilization of young dogs produced a 66% loss of metaphyseal spongiosa in the third metacarpus, a 50% loss in the radius, and a 25% loss in the humerus. In older animals, the loss amounted to 54%, 46%, and 37%, respectively. In both age groups, the loss of the spongiosa exceeded that of the compacta in the same bones, and, as in the compacta, it was greatest in the small peripheral bones. Although maximal loss occurs during the first 24 to 32 weeks, it may continue to a lesser degree up to 60 weeks and perhaps beyond 60 weeks of immobilization. Since bone loss can occur only on bone surfaces, the earlier and greater loss from the spongiosa may be explained in part by the higher endosteal surface-to-volume ratio of spongy bone. Given a similar bone structure and physiology in man and dog, the observations made in this study may apply to man as well.

Age Factors↗