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At least 1,117 records · Page 62Linked to original sources
PubMed2007

Effect of proximal femoral osteoporosis on cementless hip arthroplasty: a short-term clinical analysis.

OBJECTIVE: The aim of this retrospective investigation was to explore the influence of femoral osteoporosis on short-term curative effects of cementless hip arthroplasty and to evaluate the femoral metaphyseal bone mineral density (BMD) for femoral osteoporosis in order to guide prosthesis choice and rehabilitation. METHODS: We performed 127 total arthroplasty operations between June 1999 to February 2003 and investigated 49 cementless hip replacements with the Metalcancellous cementless Lubeck II system being used in all hips. There were twenty men and twenty-nine women whose mean age at the time of the operation was 60 years (range, 52~81 years). The patients were divided into osteoporosis or normal groups according to the femoral metaphyseal BMD measured preoperatively. The average duration of follow-up was 30 months (range, 8~52 months). We evaluated all of the patients from a clinical standpoint with use of a standard-terminology questionnaire with respect to the short-term curative effects and patients' satisfaction. Hip pain status and functional ability were important indicators of treatment efficacy. RESULTS: Harris hip score and patients' satisfaction in femoral osteoporosis patients who underwent noncemented hip arthroplasty were lower (P=0.004, P=0.03) while the incidence of thigh pain was higher (P=0.03) than the patients with non-osteoporosis. CONCLUSION: The higher incidence of pain, as well as the decrease in function experienced by the patients in osteoporosis group, supports the case that cementless arthroplasty is not a better choice for those patients and that we had better select prosthesis based on the femoral metaphyseal BMD.

Aged↗
PubMed1999

Posttraumatic tibia valga in children. A long-term follow-up note.

BACKGROUND: We reevaluated seven patients who initially had been managed nonoperatively because of a progressive valgus deformity that had occurred within approximately twelve months after satisfactory healing of a proximal tibial metaphyseal fracture sustained at an average age of four years (range, eleven months to six years and four months). All seven patients were described in a previous report from our institution, published in 1986. In that report, spontaneous improvement of the angulation was documented after an average duration of follow-up of thirty-nine months and nonoperative treatment of the deformity was recommended. METHODS: The patients were followed radiographically for an average of fifteen years and three months (range, ten years and four months to nineteen years and eleven months) after the injury. The radiographs were reviewed to determine the metaphyseal-diaphyseal angle, the mechanical tibiofemoral angle, the proximal and distal tibial remodeling angles, the limb-length discrepancy, and the deviation of the mechanical axis of the limb from the center of the knee joint. Knee function was assessed with use of the rating system of the Cincinnati Sportsmedicine and Orthopaedic Center, and ankle function was assessed with use of the rating system of the American Orthopaedic Foot and Ankle Society. RESULTS: Every patient had spontaneous improvement of the metaphyseal-diaphyseal and mechanical tibiofemoral angles. Most of the correction occurred at the proximal part of the tibia. The mechanical axis of the limb remained lateral to the center of the knee joint in every patient, with an average deviation of fifteen millimeters (range, three to twenty-four millimeters). The affected tibia was longer than the contralateral tibia in every patient, with an average limb-length discrepancy of nine millimeters (range, three to eighteen millimeters). The knee score on the affected side was excellent for five patients and fair for two; one of the patients who had a fair score had had a tibial osteotomy at the age of sixteen years because of pain in the lateral aspect of the knee that was thought to be due to malalignment. The ankle score on the affected side was excellent for three patients and good for four. CONCLUSIONS: Spontaneous improvement of the deformity occurred in all patients and resulted in a clinically well aligned, asymptomatic limb in most. We believe that patients who have posttraumatic tibia valga should be followed through skeletal maturity and that operative intervention should be reserved for patients who have symptoms secondary to malalignment.

Adolescent↗
PubMed2004

Survival of microvascular physeal allograft transplants following withdrawal of short-term postoperative immunosuppression.

BACKGROUND: Physeal necrosis following vascularized allograft transplantation occurs because of vascular rejection. The effect of immunosuppression withdrawal on physeal viability after bone-healing to the recipient site was investigated with use of a validated model for heterotopic microvascular transplantation of rabbit tibial physeal allografts. Our hypothesis was that an allograft survives after withdrawal of immunosuppression only if bone-healing, and therefore epiphyseal and metaphyseal vascular continuity, occurs between the transplanted physis and the recipient bone. METHODS: Physeal grafts with adjacent exposed epiphyseal and metaphyseal bone were transplanted to allogeneic recipients. Graft circulation was restored microsurgically. The immunosuppression regimen consisted of cyclosporine, administered for six weeks, followed by withdrawal of immunosuppression for four weeks. The animals were killed at ten weeks postoperatively. Group I consisted of twelve allografts that were transferred with bone contact between the transplanted graft and the iliac crest recipient site, whereas group II consisted of twelve allografts transplanted without bone contact. Control groups had identical surgical procedures without immunosuppression. Longitudinal growth was assessed by fine-detail radiography, and osseous union was evaluated histologically. Transplanted physes were evaluated histologically, and cellular viability was quantified by bromodeoxyuridine uptake. Two-way analysis of variance was used to compare physeal viability between groups. RESULTS: Following immunosuppression withdrawal, the physeal grafts with bone contact had significantly greater viability indices (16.0 +/- 2.9 compared with 0.0 +/- 0.0, p < 0.005) and decreased longitudinal growth (5.1 +/- 1.9 mm compared with 10.3 +/- 3.5 mm, p < 0.05), and they demonstrated histological features that were consistent with continued viability associated with mild rejection compared with grafts transplanted without bone contact. Abnormalities of physeal architecture, however, were seen routinely. All control physes transferred without immunosuppression were nonviable and did not grow. CONCLUSIONS: The viability of physeal allograft transplants is preserved following the withdrawal of immunosuppression, provided that the graft design and recipient site preparation allow for epiphyseal and metaphyseal neovascularization mediated by bone-healing between graft and recipient.

Animals↗
PubMed2006

Metal-on-metal hybrid surface arthroplasty. Surgical Technique.

BACKGROUND: Following the reintroduction of metal-on-metal articulating surfaces for total hip arthroplasty in Europe in 1988, we developed a surface arthroplasty prosthetic system using a metal-on-metal articulation. The present study describes the clinical and radiographic results of the first 400 hips treated with metal-on-metal hybrid surface arthroplasties at an average follow-up of three and a half years. METHODS: Between November 1996 and November 2000, 400 metal-on-metal hybrid surface arthroplasties were performed in 355 patients. All femoral head components were cemented, but only fifty-nine of the short metaphyseal stems were cemented. The patients had an average age of forty-eight years, 73% were men, and 66% had a diagnosis of osteoarthritis. Clinical and radiographic follow-up was performed at three months postoperatively and yearly thereafter. RESULTS: The majority of the patients returned to a high level of activity, including sports, and 54% had activity scores of >7 on the University of California at Los Angeles activity assessment system. Kaplan-Meier survivorship curves demonstrated that the rate of survival of the components at four years was 94.4%. For patients with a surface arthroplasty risk index score of >3, the rate of survival of the components at four years was 89% compared with a rate of 97% for those with a score of <or=3. The patients with a higher risk index were 4.2 times more likely to undergo revision to a total hip replacement at four years. Twelve hips (3%) had a revision to a total hip replacement. Seven of the twelve hips were revised because of loosening of the femoral component, and three were revised because of a femoral neck fracture. Substantial radiolucencies were seen around sixteen uncemented metaphyseal femoral stems. No femoral radiolucencies were observed among the hips in which the metaphyseal stem was cemented. The most important risk factors for femoral component loosening and substantial stem radiolucencies were large femoral head cysts (p = 0.029), patient height (p = 0.032), female gender (p = 0.005), and smaller component size in male patients (p = 0.005). CONCLUSIONS: The preliminary experience with this hybrid metal-on-metal bearing is encouraging. Optimal femoral bone preparation and component fixation are critical to improving durability. The metal-on-metal hybrid surface arthroplasty is easily revised to a standard femoral component if necessary.

Adolescent↗
PubMed1986

Histology and histomorphometry of the tibia growth in two turkey strains.

Qualitative and quantitative histological methods on decalcified and undecalcified specimens were used for comparing the linear and radial growth of the tibia in two turkey strains: a light strain, Betina, without leg problems and a heavy strain, Maxiboul, with leg problems. Groups of 10 clinically healthy male turkeys of each strain were studied at 2, 6, 8, 16, and 20 weeks of age. Three histomorphometric parameters of longitudinal growth were quantitated in the proximal growth plate and metaphysis. These were: height of the proliferative zone, density of ossification buds (metaphyseal sprouts), and volume of metaphyseal trabecular bone. Four histomorphometric parameters of radial growth were quantitated in the diaphysis. These were cortical thickness, active zone/total surface, density of maturing osteons in the active zone, and bone apposition rate at the maturing primary osteons level. The results showed some evidence for factors predisposing to leg problems in the Maxiboul strain. At 8 weeks, the Maxiboul strain had a lower ossification bud density (13.1/mm2 vs. 20.7/mm2; P less than .05) and a lower metaphyseal trabecular bone volume (16.4% vs. 22.0%; P less than .05) when compared to the Betina strain. No difference was detected in the cortical thickness of the diaphysis in the two strains except at 2 weeks of age (799 microns vs. 387 microns; P less than .001), despite the heavier weight of the Maxiboul strain.

Animals↗
PubMed2001

Stimulatory effect of zinc on insulin-like growth factor-I and transforming growth factor-beta1 production with bone growth of newborn rats.

The effect of zinc, an essential trace element, on insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 production was investigated to determine the role of this metal in bone growth of newborn rats. Femoral-diaphyseal and metaphyseal tissues were obtained between 1 and 28 days after birth of newborn rats, and cultured for 24 h in a serum-free Dulbecco's modified Eagle's medium containing either vehicle or zinc sulfate (10(-6) - 10(-4) M). Protein concentration in the medium was significantly increased by culture with bone tissues of newborn rats with increasing age (14 and 21 days). Medium IGF-I and TGF-beta1 concentration was gradually reduced with increasing age after birth. The presence of zinc (10(-5) and 10(-4) M) caused a significant increase in protein, IGF-I, and TGF-beta1 concentrations in the medium cultured with the diaphyseal or metaphyseal tissues obtained at 7 and 14 days after birth. The expression of IGF-I and TGF-beta1 mRNA was demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) analysis in the diaphyseal and metaphyseal tissues cultured for 24 h using rat IGF-I or TGF-beta1-specific primers. These expressions were significantly raised in the presence of zinc (10(-4) M) in culture medium. The present study demonstrates that zinc has a stimulatory effect on IGF-I and TGF-beta1 production in the femoral tissues with bone growth of newborn rats.

Animals↗
PubMed1991

Induction of osteochondromas by periosteal resection.

Forty immature and 40 mature rabbits which received periosteal resection from the proximal metaphyses or diaphyses of tibiae were evaluated for the occurrence of osteochondromas at the sites of periosteal defects. Thirteen of 20 immature tibiae with the periosteal defects at their proximal metaphyses showed osteochondromas covered by hyaline cartilage caps. We assume that the occurrence of osteochondroma at the metaphyseal region of growing long bone, where the periosteal defects were made, is due primarily to a decrease in the power of the periosteum to control the circumferential growth of the metaphysis, and is due secondarily to an abnormal proliferation of cartilage progenitors located in Ranvier's groove.

Animals↗
PubMed1999

Behavior of the femoral stem in the Bihapro hip prosthesis.

This study evaluated the hydroxyapatite-coated femoral stem of the Bihapro hip prosthesis (Biomet Ltd, Bridgend, United Kingdom) using radiography, TC-99 scintigraphy, and bone densitometry. Thirty stems with >2 years of follow-up (mean: 31 months) were evaluated. No loosening or changes in the position of the implant were seen, and the mean subsidence was 2.2 mm. Radiography revealed a densification in the metaphyseal zone with reconstruction of the trabecular lines in 21 cases, while in 22 patients, radiolucent lines in the distal area of the femoral component were observed. Scintigraphy showed a diaphyseal normo-captation in 19 cases and a hypercaptation <1.4 with a mean index of 1.1 in 10 patients. Metaphyseal hypercaptation >1.4 was seen in 24 patients. Bone densitometry revealed increased density in the metaphyseal zones in 29 patients with a periprosthetic/normal bone quotient of 1.4.

Bone Density↗
PubMed1999

[Role of growth hormone underproduction and support load deficit in development of muscle atrophy and osteopenia in tail-suspended rats].

In a 20-day experiment with tail-suspended male rats histological and histomorphometric techniques were used to study the effects of growth hormone, thyroxin, and graded support loads on the progress of atrophy in soleus and gastrocnemius m.m., tibial metaphyses spongiosis, and growth of tibiae. Daily injections of growth hormone at a dose of 0.5 mg/kg of the body mass were found to restore the longitudinal growth of tibiae and to suppress osteopenia in the spongiosis of metaphyses; however, they did not have any noteworthy effect on the muscular atrophy in the suspended rats. Support loading of the hind limbs for 2 hours a day in parallel to the treatment with growth hormone and thyroxin (0.02 mg/kg of the body mass per a day) suppressed the atrophy in soleus m. but not in gastrocnemius m. They were not able to oppose to osteoporosis in tibial metaphyses spongiosis; tibial growth was not normalized. Thyroxin did not appear to markedly influence muscle and bone atrophies; moreover, it made hypofunctioning of the thyroid more intense and, when combined with the growth hormone, masked the positive effect of the latter on the rats' bones.

Animals↗
PubMed1999

[Elastic intramedullary nailing of the tibia with the Marchetti-Vicenzi nail. 43 treated cases].

PURPOSE OF THE STUDY: The purpose of this study was to analyse the results of tibial intramedullary nailing using an unreamed "Universal Elastic Bundle Nail". MATERIAL AND METHODS: Forty-three intramedullary nailing of tibial shaft were done in 43 patients with recents fractures, from May 1993 and May 1996. There were 36 males and 7 females. The average age was 31.5 years (range 17-68 years). Thirty-three were injured in a traffic accident (20 motorcycles, 5 pedestrians and 8 car passengers), seven were injured in a home accident (fall) and three had a sport injury. There were 13 open fractures according to Gustilo: 5 grade I, 7 grade II and one grade III B. Eight fractures involved the proximal metaphyseal part of the tibia, 16 the distal metaphyseal part and 14 the tibial shaft; in five cases there were segmental fractures. According to AO classification there were: 10 fractures type A, 24 fractures type B and 9 fractures type C (5 segmental fractures). In 5 cases there were associated femoral fractures: three ipsilaterals and two controlaterals. All were treated in the same time: four by UEBN device and one by AO's nail. All the patients with type B and C fractures were positioned on a Maquet table with a boot traction or transcalcaneal pin traction (in the distal fractures). The nail was introduced after closed reduction through a vertical transpatellar tendon incision, without reaming procedure. RESULTS: Forty one fractures healed after an average time of 96 days (60-120). In 11 open fractures bone union occurred after 98 days (85-120). The distal fractures healed after a mean time of 86 days (60-120), proximal fractures in 123 days and mid shaft fractures in 98 days. In type A fractures bone union occurred after an average time of 68 days, while bone union occurred after a mean time of 100 days in type B and C fractures. Two patients with an open proximal type B fracture, had a delayed union: both healed after proximal screws removal. Two fractures healed with a valgus angulaton 5 degrees and 10 degrees. No infection, no loss of reduction and no bundle migration has been noted. DISCUSSION: The Marchetti-Vicenzi's nail (UEBN) permitted a stable fixation in tibial fractures. The use of this unreamed nailing coupled with an automatic distal locking in the metaphyseal cancellous bone, reduced operative time and shortened X Ray's radiation exposure. At the follow-up fracture healing occurred in 41 cases 95.3 p. 100 at four months. Two delayed union occurred after four months, the two cases were open fractures grade II. All the two cases healed after secondary procedure without any loss of function. Malunion occurred in two patients (in only one case there was a major valgus angulation 10 degrees), the two cases were related to technical error. We had no cases of infection or leg shortening or bundle migration in the ankle joint. CONCLUSION: We believe that Universal Elastic Bundle Nail allows a stable and safety fixation in open or closed tibial fractures without pseudarthrosis and without infection (in our series).

Accidents↗
PubMed2003

[Influence of proximal stem geometry and stem-cement interface characteristics on bone and cement stresses in femoral hip arthroplasty: finite element analysis].

PURPOSE OF THE STUDY: The combined effects of proximal canal filling and stem-cement surface characteristics on stresses in the cement and bone in femoral hip arthrosplasty were investigated by finite element analysis. MATERIAL AND METHODS: Our finite element study of a femoral implant fitted with a stainless steel stem was based on a set of 4 models with decreasing metaphyseal fill, designed to simulate loading before the occurrence of any deterioration in the cement-bone interface. Thus, the cement was represented fully bonded to the bone. The implant-cement interface was modeling in the bonded and debonded states. First a vertical load was applied to the implant to simulate the conditions of the bearing phase of gait. Second, a rotational load was applied to the implant. Torsional loading tests were found to be satisfactory for studying variations in shape of the proximal portion of femoral implants because they simulate the most critical loading conditions such as stair climbing or chair rising. RESULTS: With the bonded implant-cement surface, bone stresses were rather distal, whereas they were mainly proximal with the debonded implant-cement interface. Under rotational loading, debonded implants produced less normal tensile and shear stresses in the proximal portion of the cement mantle. In contrast, compressive cement stresses were higher with debonded implants. In the debonded state, the rotational stability of the implant was found to be closely related to the degree of metaphyseal fill. CONCLUSION: In conclusion, the use of implants with a debonded metal-cement interface and with optimal metaphyseal filling should preserve the cement-bone interface from excessive shear and tensile stresses, while providing good rotational stability.

Arthroplasty, Replacement, Hip↗
PubMed1992

Effects of 1 alpha(OH)-vitamin D3 and 24,25(OH)2-vitamin D3 on long bones of glucocorticoid-treated rats.

Glucocorticoids may induce osteopenia in experimental animals and in man. In order to study the possible effects of vitamin D metabolites in the prevention of glucocorticoid-induced osteopenia in rats, we administered 1 alpha(OH)-vitamin D3, 24,25(OH)2-vitamin D3 or a combination of both metabolites, by intragastric intubation, to rats treated daily by intramuscular injections of 10 mg/kg cortisone acetate. Treatment with the vitamin D metabolites started after 1 month of glucocorticoid therapy, at the time osteopenia was already present. Cortisone acetate decreased the gain weight, increased alkaline phosphatase (AP) and decreased Ca serum levels. It also decreased tibial wet and ash weight and tibial Ca content. Computerized histomorphometry of sections from the upper tibia showed decreased epiphyseal bone volume and increased bone marrow volume; decreased height of hypertrophic cartilage in the growth plate and decreased amount of persisting cartilage in the metaphyseal bone trabeculae were also observed. Administration of 24,25(OH)2D3 alone did not reduce these glucocorticoid-induced bone changes and sometimes even worsened them. 1 alpha(OH)D3 reversed many of the deleterious effects of cortisone acetate. It reduced serum AP levels, increased serum Ca levels, increased bone ash weight, epiphyseal and metaphyseal bone volume, with a concomitant reduction in epiphyseal and metaphyseal bone marrow volume. The best results were obtained by a combination of 1 alpha(OH)D3 and 24,25(OH)2D3. It is presumed that both metabolites are needed to reduce the impact of glucocorticoids on bone. 1 alpha(OH)2D3 acts on the gut, increasing Ca absorption (which was decreased by glucocorticoids), and 24,25(OH)2D3 directly acts on bone to enhance bone formation and mineralization.

24,25-Dihydroxyvitamin D 3↗
PubMed2004

Metal-on-metal hybrid surface arthroplasty: two to six-year follow-up study.

BACKGROUND: Following the reintroduction of metal-on-metal articulating surfaces for total hip arthroplasty in Europe in 1988, we developed a surface arthroplasty prosthetic system using a metal-on-metal articulation. The present study describes the clinical and radiographic results of the first 400 hips treated with metal-on-metal hybrid surface arthroplasties at an average follow-up of three and a half years. METHODS: Between November 1996 and November 2000, 400 metal-on-metal hybrid surface arthroplasties were performed in 355 patients. All femoral head components were cemented, but only fifty-nine of the short metaphyseal stems were cemented. The patients had an average age of forty-eight years, 73% were men, and 66% had a diagnosis of osteoarthritis. Clinical and radiographic follow-up were performed at three months postoperatively and yearly thereafter. RESULTS: The majority of the patients returned to a high level of activity, including sports, and 54% had activity scores of >7 on the University of California at Los Angeles activity assessment system. Kaplan-Meier survivorship curves demonstrated that the rate of survival of the components at four years was 94.4%. For patients with a surface arthroplasty risk index score of >3, the rate of survival of the components at four years was 89% compared with a rate of 97% for those with a score of </=3. The patients with a higher risk index were 4.2 times more likely to undergo revision to a total hip replacement at four years. Twelve hips (3%) had a revision to a total hip replacement. Seven of the twelve hips were revised because of loosening of the femoral component, and three were revised because of a femoral neck fracture. Substantial radiolucencies were seen around sixteen uncemented metaphyseal femoral stems. No femoral radiolucencies were observed among the hips in which the metaphyseal stem was cemented. The most important risk factors for femoral component loosening and substantial stem radiolucencies were large femoral head cysts (p = 0.029), patient height (p = 0.032), female gender (p = 0.005), and smaller component size in male patients (p = 0.005). CONCLUSIONS: The preliminary experience with this hybrid metal-on-metal bearing is encouraging. Optimal femoral bone preparation and component fixation are critical to improving durability. The metal-on-metal hybrid surface arthroplasty is easily revised to a standard femoral component if necessary. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.

Adolescent↗
PubMed2004

Expression of albumin in bone tissues and osteoblastic cells: involvement of hormonal regulation.

The expression of albumin in bone-related cells was investigated. Bone marrow cells and femoral-diaphyseal and -metaphyseal tissues were obtained from normal rat femur. Western blot analysis for protein in the lysate of bone marrow cells showed expression of albumin. The production of albumin was found in the bone marrow cells and femoral-diaphyseal and -metaphyseal tissues obtained from rat femur. When the femoral-diaphyseal and -metaphyseal tissues were cultured for 48 h in a serum-free medium in vitro, albumin was greatly released into culture medium from the bone tissues. The expression of albumin in osteoblastic MC3T3-E1 cells was investigated by Western blot analysis. Osteoblastic cells were cultured for 48 h in a serum-free medium containing either vehicle, parathyroid hormone (1-34) (human PTH; 10(-7) M), 17beta-estradiol (10(-9) M), insulin-like growth factor-I (IGF-I; 10(-8) M) or zinc sulfate (10(-4) M). The production of albumin in osteoblastic cells was significantly enhanced in the presence of PTH, IGF-I, 17beta-estradiol or zinc sulfate. These factors stimulated significantly the release of albumin from osteoblastic cells into culture medium. The effect of IGF-I (10(-8) M) in increasing the production of albumin in osteoblastic cells was completely prevented in the presence of cycloheximide (10(-7) M), an inhibitor of protein synthesis, or 5, 6-dichloro-1-beta-D-ribofuranosyl-benzimidazole (DRB; 10(-6) M), an inhibitor of transcriptional activity. This study demonstrates that albumin is expressed in bone marrow cells and osteoblastic cells, and that the production of albumin in osteoblastic cells is enhanced by various bone anabolic factors in vitro.

3T3 Cells↗
PubMed2006

[Use of Hoffman external fixation for extra-articular upper metaphysealtibial fractures].

Treatment of extra-articular upper metaphyseal tibial fractures can be difficult. Orthopedic treatment is frequently complicated by second displacement These fractures are inappropriate for locked intra-medullary nailing because of the shorteness of the proximal extremity. Damages of soft tissues. frequently associated with these factures, expose internal osteosynthesis to many risks. For these reasons, we opted for external fixation. Our study was a retrospective analysis of 46 extra-articular metaphyseal tibial fractures treated by external fixation with Hoffman material. The average follow-up was 24 months. Consolidation was obtained within 4 months in average. Septic complications. inherent to the method were uncommon or minor. Functional results were satisfactory in 84% of cases. So, external fixation with Hoffman material. with particular recommandations, is a promising method for the treatment of extra-articular of proximal metaphyseal tibial fractures.

Adult↗
PubMed1990

The relative contribution of individual osseous circulations to diaphyseal cortical blood supply.

The potential contributions of periosteal, nutrient (medullary), and epiphyseo-metaphyseal circulations, respectively, to cortical blood supply have been investigated by isolating each using a diaphyseal segment model. The periosteal circulation was isolated by creating and nailing a 2-cm segment of the adult rabbit tibial diaphysis. The medullary circulation was isolated by external application of a silastic sheath to a diaphyseal segment. The epiphyseo-metaphyseal circulation was isolated by combining both techniques. The residual potential routes of blood supply to each isolated segment were studied by arterial radiography and by histology in a postmortem study and in a survival study at various times up to 4 weeks after the isolation procedure. Both centrifugal and centripetal arterial supply were observed in the postmortem study. In the survival study, cortical arterial perfusion was observed up to 4 weeks following isolation of the periosteal circulation but only up to 2 weeks following isolation of the nutrient (medullary) circulation. At 4 weeks, the segment was not perfused when supplied only by the epiphyseo-metaphyseal system. It would appear, therefore, that the periosteal circulation provides a potential source of arterial supply to the diaphyseal cortex. Furthermore, an intact periosteal circulation seems to be necessary if an isolated segment of cortical bone is to continue to be adequately perfused with blood.

Angiography↗
PubMed1985

Classification, diagnosis, and treatment of transitional fractures of the distal part of the tibia.

I studied the anatomical relationships in thirty-two transitional fractures of the distal part of the tibia by standard radiography and in thirteen of these patients by computerized axial tomography. Three different configurations of fractures could be identified: biplane fractures and two different types of triplane fractures (Type I and Type II). In the biplane lesion the fracture is restricted to the epiphysis, while the triplane fractures are characterized by a wedge of metaphyseal bone. In the Type-I triplane lesion the metaphyseal portion of the fracture ends in the physis, while in the Type-II triplane lesion the metaphyseal portion of the fracture line extends through the physis into the epiphysis and the joint. On the anteroposterior radiograph, the epiphyseal fracture line in both the biplane and the two types of triplane fractures may be found anywhere from the extreme medial to the extreme lateral position. Its location, however, is exclusively dependent on the maturity of the distal tibial physis and is not influenced by the mechanism of injury. The use of computerized axial tomography has revealed the true dimensions of these fractures, and the diagnosis of biplane and triplane fractures can now be made by standard radiography alone. However, the evaluation of undisplaced or only slightly displaced Type-II triplane fractures will still occasionally require the use of computerized axial tomography. Displaced transitional fractures with a fracture gap of more than two millimeters in the weight-bearing portion of the epiphysis require open reduction. If the gap is less than two millimeters, non-operative treatment with a plaster cast is sufficient.

Adolescent↗
PubMed1979

Technetium colloid bone marrow imaging in Fanconi's anemia.

Four patients with Fanconi's anemia were evaluated with 99mTc-sulfur colloid bone marrow scans. The scans revealed similar paradoxical and irregular tracer distribution in all four patients. Normal to increased activity was demonstrated in the proximal metaphyses of the humeri with varying degrees of increased activity in more primitive marrow sites in the distal diaphyses of the humeri and tibia, the distal metaphyses of the humeri and femora, and the proximal metaphyses of the ulnae, radii, and tibia. Skip areas of normal distribution were seen in the proximal diaphyses of the humeri and femora. Although the scan reflects only the reticuloendothelial portion of bone marrow, it may be of some value in the differential diagnosis of pancytopenia.

Abnormalities, Multiple↗