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PubMed1978

Hematogenous osteomyelitis of metaphyseal-equivalent locations.

Flat and irregular bones have anatomic subdivisions comparable to long bones. This concept is useful in the radiograpic evaluation of solitary bone lesions. Areas adjacent to cartilage are metaphyseal-equivalent locations. Prior to skeletal maturation, metaphyseal-type vascular anatomy predisposes these sites to involvement by hematogenous osteomyelitis. Approximately 30% of cases of hematogenous osteomyelitis affect these metaphyseal-equivalent sites and often present difficult diagnostic challenges. Forty-nine patients with this condition are described.

Adolescent↗
PubMed1996

A regional approach to the classic metaphyseal lesion in abused infants: the proximal tibia.

OBJECTIVE: The purpose of this study was to systematically analyze the spectrum of morphologic alterations of the classic metaphyseal lesion (CML) involving the proximal tibia of abused infants and to identify features that aid in the radiologic diagnosis and assessment of healing. MATERIALS AND METHODS: Thirty-one infants who died with evidence of inflicted skeletal injury were studied with high-detail skeletal surveys, resected specimen radiography, and histopathologic analysis. The number of fractures identified, the portions of the proximal tibial metaphyses involved, and the age of the lesions were assessed. RESULTS: Seventeen proximal tibial CMLs were noted. They were bilateral in six instances and unilateral in five. When the lesion was visible radiographically, it always involved the medial aspect of the metaphysis, with involvement of the lateral metaphyseal margin in more extensive injuries. Fractures tended to be less conspicuous when acute and were more easily recognizable with healing, especially with specimen radiography. Histologically, the fracture line consistently undercut the medial subperiosteal bone collar. Extension of hypertrophic chondrocytes from the growth plate into the region of fracture was a common finding. CONCLUSION: The CML of the proximal tibia has distinctive radiologic and histopathologic characteristics that relate to the anatomy of the region. Because the proximal tibia is a common site for this strong indicator of infant abuse, the region should be carefully evaluated with well-collimated, high-detail skeletal radiographs in all cases of suspected infant abuse.

Child Abuse↗
PubMed1996

A regional approach to classic metaphyseal lesions in abused infants: the distal tibia.

OBJECTIVE: The purpose of this study was to analyze systematically the spectrum of morphologic alterations of classic metaphyseal lesions (CML) involving the distal tibia of abused infants and to identify features that assist in the radiologic diagnosis and assessment of healing. MATERIALS AND METHODS: Thirty-one infants who died with evidence of inflicted injury were studied with high-detailed skeletal surveys, resected-specimen radiography, and histopathologic analysis. The number of fractures identified, the portions of the distal tibial metaphyses involved, and the age of the lesion were assessed. RESULTS: A total of 16 CML of the distal tibia were noted. Eight infants had unilateral injury that always involved the left side, and four had bilateral lesions. When a CML was visible radiographically, it was always seen along the medial aspect of the metaphysis; lateral metaphyseal involvement was evident with more extensive injuries and always accompanied medial involvement. Fractures tended to be less conspicuous when acute and were more easily recognized with healing, especially with specimen radiography. Radiographically, the typical fracture separated a medial fragment that was tall and triangular; this appearance was histologically related to the undercutting of the long subperiosteal bone collar. In healing lesions, extension of hypertrophic chondrocytes from the growth plate into the region of the fracture was a consistent finding. CONCLUSION: CML of the distal tibia have distinctive radiologic and histopathologic characteristics that relate to the anatomy of the region. Visualization of these fractures depends on the quality of the radiographs obtained. An understanding of the radiologic and histopathologic features of CML should aid in the recognition of this strong indicator of infant abuse.

Child Abuse↗
PubMed1996

A regional approach to the classic metaphyseal lesion in abused infants: the proximal humerus.

OBJECTIVE: The purpose of this study was to systematically analyze the spectrum of morphologic alterations of the classic metaphyseal lesion (CML) involving the proximal humerus of abused infants and to identify radiologic features that aid in the diagnosis and assessment of healing. MATERIALS AND METHODS: Thirty-one infants who died with evidence of inflicted skeletal injury were studied with high-detail skeletal surveys, resected specimen radiography, and histologic analysis. In each infant, the number of fractures, the involved portions of the proximal humeral metaphyses, and the age of the lesion were assessed. RESULTS: Seven proximal humeral CMLs were seen in four infants. Radiography of the only infant with an acute injury revealed no fracture; however, evidence of trabecular disruption was found histologically. Radiographic patterns in the six healing injuries included focal corner-fracture appearance, transmetaphyseal radiolucency, irregularity of the metaphyseal margin, and flame-shaped mineralized extensions into the physeal cartilage. Histologically, all CMLs undercut the lateral subperiosteal bone collar, explaining the corner-fracture appearance. Focal and diffuse thickening of the zone of hypertrophic chondrocytes was seen, and peninsulas of primary spongiosa surrounded by hypertrophied cartilage corresponded to the flame-shaped densities revealed radiographically. The fracture morphology was better seen on specimen radiography than on skeletal survey images. CONCLUSION: CML of the proximal humerus has distinctive radiologic and histopathologic characteristics that relate to the anatomy of the region. In our study, changes at the chondroosseous junction revealed by radiography correlated well with histologic evidence of healing. Although the proximal humerus is a less common location for CML than the lower extremity, the proximal humerus should be carefully scrutinized on high-detail radiographs in cases of suspected infant abuse.

Child Abuse↗
PubMed2000

Microcrack density and length in the proximal and distal metaphyses of the humerus and radius in dogs.

OBJECTIVE: To compare microcrack density and length in the proximal and distal metaphyses of the humerus and radius in dogs. SAMPLE POPULATION: Left humerus and radius from each of 10 dogs of medium to large size. PROCEDURE: Metaphyseal specimens were bulk stained in 1% basic fuchsin in graded alcohols and embedded in methylmethacrylate. For quantification of fatigue-induced microscopic damage, transverse sections were prepared from proximal and distal metaphyseal regions, and length and density of microcracks were determined, using light microscopy. RESULTS: Bone region, age, and body weight were not significantly associated with microcrack density or length. CONCLUSIONS AND CLINICAL RELEVANCE: The hypothesis that fatigue-induced injury (increased microcrack density and length) caused by cyclic loading associated with daily activity is greater in bone regions prone to development of osteosarcoma was not supported by data from this study.

Animals↗
PubMed1997

Metaphyseal-diaphyseal angle in Blount's disease. A 30-year follow-up of 13 unoperated children.

We analyzed the metaphyseal-diaphyseal angle in 13 patients with infantile Blount's disease, who had been followed without treatment during the entire growth period and without any form of realignment procedure in adulthood. On diagnosis at 23 (17-35) months of age, the metaphyseal-diaphyseal angle varied between 7 degrees and 25 degrees. At follow-up, most of the legs were almost straight. We found that the diagnosis of Blount's disease cannot be based solely on the metaphyseal-diaphyseal angle and that a bowed knee must be followed with repeated examinations before it can be decided whether treatment is needed.

Adult↗
PubMed2007

Effects of etoposide and cyclophosphamide acute chemotherapy on growth plate and metaphyseal bone in rats.

Pediatric cancer chemotherapy is known to cause bone growth arrest and osteoporotic changes, and yet the underlying mechanisms remain largely unknown. This project investigated effects of acute chemotherapy with topoisomerase inhibitor etoposide (Eto, 80 mg/kg), alkylating agent cyclophosphamide (Cyc, 240 mg/kg) or their combination (Cyc 120 mg/kg + Eto 50 mg/kg) on structural and cellular changes in the growth plate cartilage and metaphyseal bone, two important regions responsible for bone growth and bone mass accumulation. On day 3 after a single injection with either of the three treatments, although the total growth plate thickness was not significantly altered, the cellularity and height of the proliferative zone were significantly reduced. It was shown that while Eto suppressed chondrocyte proliferation, Cyc induced apoptosis in the growth plate proliferative zone. In the metaphysis, although osteoblastic cell surface was decreased in all three treated groups, the trabecular bone bone volume (BV/TV%) was not significantly altered on day 3. On the other hand, the acute chemotherapy reduced heights of both primary and secondary spongiosa trabecular bone. Therefore, Eto and/ or Cyc chemotherapy altered survival or proliferation of growth plate chondrocytes and metaphyseal osteoblastic cells and reduced heights of metaphyseal spongiosa trabecular bone, which may contribute to chemotherapy side effects of these two drugs on bone lengthening and bone mass accumulation.

Animals↗
PubMedDate not supplied

Oblique metaphyseal osteotomy for the correction of Tailor's bunions: a 3-year review.

This study presents a 3-year review of patients undergoing a fifth metaphyseal osteotomy for the treatment of Tailor's bunions. Postoperative analysis consisted of patient's subjective appraisal, activity level, physical examination, and radiographic studies. The fifth metaphyseal osteotomy, in this study, reduced lateral deviation and fourth-fifth intermetatarsal angles to less than or equal to normal values, while decreasing intermetatarsal head distance and returning the fifth metatarsophalangeal joint to congruency. Patient satisfaction was high while providing a low incidence of transfer lesions. This manuscript demonstrates the fifth metaphyseal osteotomy to be a viable treatment for Tailor's bunions.

Adolescent↗
PubMed1989

Distal metaphyseal tibial nonunions associated with significant bowing deformity and cortical bone loss: treatment with human bone morphogenetic protein (h-BMP) and internal fixation.

Distal tibial metaphyseal nonunions with significant posterior bowing deformities are extremely difficult to manage and may require the use of additional healing factors to achieve union. Four patients with complex multiple failed surgically treated distal metaphyseal nonunions were treated with debridement of the nonunion, correction of deformities, internal stabilization, and augmentation with human bone morphogenetic protein implants (h-BMP). All patients had, following resection of the anterior cortical sequestrum, a significant cortical defect extending from a level proximal to the ankle joint to the distal tibial metaphysis. The average number of failed previous surgical procedures were 5.8 and average age was 35.3 years. Symptomatic nonunion averaged 24.8 months. All patients received h-BMP combined with insoluble noncollagenous proteins (iNCP) either in a delivery form of coated polylactic polyglycolic acid strips (1 x 13 cm.) or in gelatin capsules. The h-BMP/iNCP implants were placed within the anterior cortical defects in contact with the residual distal metaphyseal bone. All nonunions were stabilized with internal fixation. Ankle motion was difficult to record preoperatively but good to very good ankle function was obtained at final follow-up evaluation in three of four patients. All fractures healed without further surgical treatment at an average of 4.4 months. h-BMP/iNCP protein implants were felt to be of benefit in the healing of these difficult fracture problems.

Adult↗
PubMed1989

[Extensometry and primary anchorage of femur implants. Study of the upper metaphyseal intracortical support of the B.P.R cement-less implant].

This study uses extensometry to compare the distribution of strain on a fresh femur before and after implantation of various titanium prostheses: one is a cementless implant with metaphyseal endosteal support; the second is a cemented prosthesis with and without calcar collar contact; the last is a titanium implant with fixation by screens. The precision of the measurements have been improved particularly in the proximal metaphyseal area using bidirectional gauges. The system of loading permits comparison of the different implants and the results obtained with the B.P.R. prosthesis compared with the cemented implant without calcar contact are very close. The effect of the collar appears very limited despite the optimal conditions of the in vivo implantation that improve the calcar-collar contact. The screw implant increases the stress shielding of the proximal area of the femur. The different steps of the experiment illustrate the strain distribution in relation to the implantation of the devices and the contact bone prosthesis. The significant endosteal fixation of the B.P.R. prosthesis in the proximal metaphyseal area allows a better primary anchorage which increases distribution of the stress and therefore results in better secondary fixation by bony ingrowth.

Biomechanical Phenomena↗
PubMed1985

[Arrangement of collagen fibers in the epiphyses and metaphyses of long bones in vertebrates].

The arrangement of collagene fibers in bone epiphyses and mataphyses form various species of reptiles and mammals was studied with a polarized light microscope and with a scanning electron microscope. In spite of the variety of shape observed in the long bone extremities of different species, the collagenic fibers arrangement in the bone epiphyses and metaphyses appeared constant. Even in reptiles known to lack a growth plate, the metaphyseal and epiphyseal fiber patterns evoked those observed in mammals. A common fiber pattern may therefore be proposed which allows the coexistence of two apparently incompatible functions: growth, that induces an increased fragility at the epiphyseo-metaphyseal junction as opposed to mechanical support, which has to cope with load and traction forces at the same junctional site.

Alligators and Crocodiles↗
PubMed1982

[A new form of familial metaphyseal dysplasia. Preliminary report].

A new hereditary form of metaphyseal dysplasia is described. A clear distinction from other forms of metaphyseal dysplasias is evident by the lack of hyperostosis of the skull, an autosomal dominant inheritance, Erlenmeyer flask deformity of the distal femoral metaphyses, and characteristic deformations of the radius. The observation is discussed, and reference is given to an identical observation published earlier.

Adolescent↗
PubMed1982

[Benign pheochromocytoma and metaphyseal bone lesions in childhood].

The authors report a 5 year-old child in whom lesions of the inferior metaphyses of the femur and superior metaphyses of the tibia were observed after successive pheochromocytomas. The aspect of the lesions, their improvement after surgical treatment of the tumors, the data in the literature and histologic findings suggest that a bone ischemia was induced by impaired microcirculation with infarction of the metaphyses.

Adrenal Gland Neoplasms↗
PubMed1993

Indonesian type of metaphyseal dysplasia.

The authors describe two Indonesian siblings affected by a hitherto undocumented form of metaphyseal dysplasia that simulates enchondromatosis. The notable clinical features were short stature and lateral bowing of the lower extremities. These features were readily recognizable at birth. The radiographic examinations showed that the metaphyseal anomalies were localized predominantly in the lower extremities, the hip joints being the most severely affected. The upper extremities showed only minimal abnormalities. The name "Indonesian type of metaphyseal dysplasia" is suggested for this autosomal recessive bone disorder.

Bone and Bones↗
PubMed1996

[Metaphyseal chondrodysplasia as differential diagnosis to rickets].

Metaphyseal chondrodysplasias are a heterogeneous group of rare disorders, with flaring and irregularity of various metaphyses. The radiographic changes are similar to rickets, but calcium and phosphorus metabolism is normal. Other types are Schmid, Spahr, McKusick, Schwachman and Jansen, which can be separated by clinical, radiographic, genetic and biochemical criteria. We present a patient with metaphyseal chondrodysplasia, Schmid type, whose bone disorder was thought to be rickets and was treated as such.

Diagnosis, Differential↗
PubMed1997

[Treatment of metaphyseal fractures of the tibia by the Ilizarov external fixator].

PURPOSE: This external fixation was used for 46 of 60 cases of proximal tibial metaphyseal fractures, over a 10 years period. The choice of an external fixation was determined by the poor reputation of internal fixation for even complex closed fractures. The reasons for the choice of the Ilizarov device were: the possibility of fitting the fixation pins close to the knee joint if necessary, the circular nature of the system, and finally the possibility of adding an intrafocal mounting (I.F.M.) which can bring the displaced bone fragments together using shaped blockstops pins. The program theoretically foresaw an initial sequence using external fixation until bone continuity was achieved, followed by a complementary plaster for one or two months. MATERIALS: 7 of the 46 fractures were lost for follow-up. Of the remaining 39 cases, there were 5 early complications: one knee septic arthritis which led to stop the method before the second month. Each of these 5 failures were due to improper use of the method. 34 cases have been followed for more than two years. RESULTS: 29 cases of consolidation of which 3 initial displacements were wrongly considered as acceptable. There was no case of displacement while the fixation was in place. There were 5 nonunions: 2 at the diaphyseal level in long metaphyso-diaphyseal fractures, 2 were comminutive metaphyseal fractures in which the fixation had been removed by error before the third month. With this fixation, neither the traumatic opening, nor the presence of a fibular fracture significantly affected consolidation. The healing period was however longer when the fracture was more extensive and comminutive. The bone gaps were treated by interfocal mounting (I.F.M.) but loss of bone stock persisted; they affected the occurrence of nonunion. CONCLUSION: Each failure of the method is explained by its improper use. The Ilizarov fixation is an excellent mechanical response to these fractures: on condition that the technical rules are respected, that an intrafocal mounting is used to remove interfragmentary gaps, and that the fixator is kept in place long enough, according to the size and comminutive nature of the fracture. This fixation is reliable in these conditions but does not compensate intrafocal bone loss exceeding 40 per cent of the metaphyseal bone mass.

Adult↗
PubMed1998

Unclassified sclerosing bone dysplasia with osteopathia striata, cranial sclerosis, metaphyseal undermodeling, and bone fragility.

Sclerosing bone dysplasias are diagnosed on the basis of a characteristic pattern of osteosclerosis and clinical manifestations; in many of them, cause and pathogenesis are still unknown. A 33-year-old man had five fractures of the humerus, tibiae, and femur as a result of mild traumatic incidents that occurred between the ages of 18 and 33 years as well as a remnant of rib fractures without apparent trauma on radiographs. His height was 158 cm (-2.2 SD). Radiographic evaluation showed cranial sclerosis, longitudinal striations in the metaphyses of the femur and tibia, fan-like striation in the ilium, metaphyseal widening in the femur and tibia, and sclerosis of the ribs. The blood chemistry findings, including serum calcium, phosphorus, and alkaline phosphatase, were normal. Biopsy from the ilium showed thick trabeculae composed of woven bone. The coexistence of osteopathia striata, cranial sclerosis, metaphyseal undermodeling, and bone fragility has not been recognized previously. Our case appears to represent a new form of sclerosing bone dysplasia.

Abnormalities, Multiple↗
PubMed2003

A proper metaphysics for cognitive performance.

The general failure to individuate component causes in cognitive performance suggests the need for an alternative metaphysics. The metaphysics of control hierarchy theory accommodates the fact of self-organization in nature and the possibility that intentional actions are self-organized. One key assumption is that interactions among processes dominate their intrinsic dynamics. Scaling relations in response time variability motivate this assumption in cognitive performance.

Cognition↗