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PubMed2001

A controlled study of the effects of alendronate in a growing mouse model of osteogenesis imperfecta.

Recent studies have reported that bisphosphonates reduce fracture incidence and improve bone density in children with osteogenesis imperfecta (OI). However, questions still persist concerning the effect of these drugs on bone properties such as ultrastructure and quality, particularly in the growing patient. To address these issues, the third-generation bisphosphonate alendronate was evaluated in the growing oim/oim mouse, an animal model of moderate-to-severe OI. Alendronate was administered to 6-week-old mice during a period of active growth at a dosage of 73 microg alendronate/kg/day for the first 4 weeks and 26 microg alendronate/kg/day for the next 4 weeks. Positive treatment effects included a reduction in the number of fractures sustained by the alendronate-treated oim/oim mice compared with untreated oim/oim mice (2.1+/-2.0 vs 3.2+/-1.6 fractures per mouse), increased femoral metaphyseal density (0.111+/-0.02 vs 0.034+/-0.04 g/cm2), a tendency towards reduced tibial bowing (4.0+/-3.7 vs 6.1+/-5.8 degrees), and towards increased femoral diameter (1.22+/-0.12 vs 1.15+/-0.11 mm). Potential negative effects included a persistence of calcified cartilage in the treated oim/oim metaphyses compared with treated wildtype (+/+) (33.8+/-11.1 vs 22.1+/-10.2%), and significantly shorter femora compared with nontreated oim/oim mice (14.8+/-0.67 vs 15.3+/-0.37 mm). This preclinical study demonstrates that alendronate is effective in reducing fractures in a growing mouse model of OI, and is also an important indicator of potential positive and negative outcomes of third-generation bisphosphonate therapy in children with OI.

Alendronate↗
PubMed2002

Femoral head vascularisation in Legg-Calvé-Perthes disease: comparison of dynamic gadolinium-enhanced subtraction MRI with bone scintigraphy.

BACKGROUND: It has been reported that MRI using a dynamic gadolinium-enhanced subtraction technique can allow the early identification of ischaemia and the pattern of revascularisation in Legg-Calvé-Perthes (LCP) disease with increased spatial and contrast resolution. Therefore, dynamic gadolinium-enhanced subtraction (DGS) MRI may be a possible non-ionising substitute for bone scintigraphy. OBJECTIVE: The purpose of this prospective study was to compare DGS MRI and bone scintigraphy in the assessment of femoral head perfusion in LCP disease. MATERIALS AND METHODS: Twenty-six DGS MR images and bone scintigraphies of 25 hips in 23 children were obtained at different stages of LCP disease; three stage I, 12 stage II, six stage III and five stage IV (Waldenström classification). The extent of necrosis, epiphyseal revascularisation pathways (lateral pillar, medial pillar, and/or transphyseal perfusion) and metaphyseal changes were analysed. RESULTS: Total agreement between both techniques was noted in the depiction of epiphyseal necrosis (kappa=1), and metaphyseal abnormalities (kappa=0.9). DGS MRI demonstrated better revascularisation in the lateral (kappa=0.62) and medial pillars (kappa=0.52). The presence of basal transphyseal reperfusion was more conspicuous with MRI. CONCLUSIONS: DGS MRI allows early detection of epiphyseal ischaemia and accurate analysis of the different revascularisation patterns. These changes are directly related to the prognosis of LCP disease and can aid therapeutic decision making.

Adolescent↗
PubMed2000

Developmental coxa vara associated with spondylometaphyseal dysplasia (DCV/SMD): "SMD-corner fracture type" (DCV/SMD-CF) demonstrated in most reported cases.

BACKGROUND: This paper reports three children with short stature: developmental coxa vara unilateral in the first case and bilateral in the other two; somewhat squared and "ovoid" vertebral bodies in the first patient, and normal to slightly tall vertebral bodies in the third; metaphyseal changes in some long tubular bones including bone fragments similar to the corner fractures seen in child abuse in all three patients. MATERIALS AND METHODS: The first and second patients were sisters; their mother, also quite short, had surgical procedures in early life for bilateral "coxa vara"; their brother, also of short stature, had bilateral coxa valga with otherwise normal femoral heads and necks, and mild metaphyseal changes associated with two minute "corner fractures" in the proximal metaphysis of the left tibia. RESULTS: A review of reported cases of developmental coxa vara associated with spondylometaphyseal dysplasia revealed that simulated corner fractures were present in most instances.

Bone and Bones↗
PubMed1997

The scapula as a window to the diagnosis of skeletal dysplasias.

Evaluation of the scapula can be useful in the diagnosis of skeletal dysplasias and helpful for the classification and delineation of new entities. A review of 2100 computerized cases of skeletal dysplasias in the International Skeletal Dysplasia Registry was performed. We found that the Luton type of platyspondylic lethal skeletal dysplasia differed radiographically from the San Diego type and Torrance type by the presence of two spikes at the inferior angle of the scapula. Hypoplasia of the body of the scapula, which is characteristic for campomelic dysplasia but not for kyphomelic dysplasia, is also present in Antley-Bixler syndrome. Radiographic and clinical similarities between campomelic dysplasia and Antley-Bixler syndrome suggest that they might be related disorders and that the latter condition should be included in the bent-bone dysplasia group. Similarity between the metaphyseal regions of the scapula and the metaphyses of the long tubular bones in the different types of short-rib polydactyly syndrome illustrates the importance of evaluation of the scapula in this group as well as in other well-defined or unknown osteochondrodysplasias.

Bone Diseases, Developmental↗
PubMed2003

The acrophysis: a unifying concept for enchondral bone growth and its disorders. I. Normal growth.

In order to discuss and illustrate the common effects on normal and abnormal enchondral bone at the physes and at all other growth plates of the developing child, the term "acrophysis" is proposed. Acrophyses include the growth plates of secondary growth centers including carpals and tarsals and apophyses, and the growth plates at the non-physeal ends of small tubular bones. The last layer of development of both physes and acrophysis is the cartilaginous zone of provisional calcification (ZPC). The enchondral bone abutting the ZPC shares similar properties at physes and acrophyses, including the relatively lucent metaphyseal bands of many normal infants at several weeks of age. The bone-in-bone pattern of the normal vertebral bodies and bands of demineralization of the tarsal bones just under the ZPC are the equivalent of those bands. The growth arrest/recovery lines of metaphyses similarly have equivalent lines in growth centers and other acrophyseal sites. Nearly the same effects can also be anticipated from the relatively similar growth plate at the cartilaginous cap of benign exostoses ("paraphysis"). The companion article will explore abnormalities at acrophyseal sites, including metabolic bone disease and dysplasias.

Bone Development↗
PubMed1996

Rickets in a 6-month-old monkey.

A 6-month-old male monkey with rickets was found dead by its keeper. Radiographic studies showed osteopenia of the entire skeletal system, a cup-shaped concavity and poor mineralization of metaphyseal ends, and markedly widened and irregular epiphyseal growth plates of the long bones and ribs. Gross anatomic findings included bowing abnormalities and microfractures in the radius, ulna, tibia, and fibia, and enlarged and widened cartilage columns extending into the metaphyses in the long bones and ribs. Histologic features included deficient mineralization and irregular disordered columns of proliferating cartilage in growth plates extending into other zones, dilated vascular channels, and poor mineralization of chondroid and osteoid tissues.

Animals↗
PubMed2001

Radiological features of 24 periosteal chondrosarcomas.

OBJECTIVE: To report the imaging findings of 24 periosteal chondrosarcomas diagnosed, staged, treated and followed in a single institution, to analyze and define their pattern, and discuss their practical consequences. DESIGN AND PATIENTS: Plain films, 16 CT examinations and four MRI examinations were reviewed, and compared with the histological evaluation. RESULTS: There were 20 men and four women, aged from 17 to 65 years. Twelve lesions involved the distal femoral metaphyses (8 posteriorly), five the proximal humerus, two the proximal metaphyses of the femur and two of the tibia, two the humeral shafts and one the iliac wing. Size varied from 4 to 11 cm. The cortex was always involved (thick, 15; thin, 13). Typical cartilaginous calcifications and cartilaginous lobules were very frequent. Radial thick periosteal bone formations (n = 6) indicated calcifications between the lobules of cartilage. Medullary involvement was rare (n = 2). All patients are alive and free of disease. CONCLUSIONS: Recognizing periosteal chondrosarcoma is of paramount importance because the prognosis is excellent after adequate local surgery alone. The patterns of other surface tumors of bone are usually different.

Adolescent↗
PubMed2004

Preservation of femoral bone mass after total hip replacements with a lateral flare stem.

Uncemented, porous-coated femoral stems rely on bone in-growth to achieve stable, long-lasting fixation. The loss of proximal femoral bone mass around hip stems has been traditionally termed "stress shielding" and has been linked to the transfer of loads to the diaphysis and the relative unloading of the proximal femur. A total of 10 total hip arthroplasties with a proximally coated lateral flare device designed to engage both cortices at the metaphyseal level were evaluated with dual-energy X-ray (DEXA) absorptiometry and qualitative radiographic changes 3 weeks after surgery and at 12, 24 and 52 weeks thereafter. All hips were radiologically stable. The DEXA measurements revealed an overall increase in the bone mineral density (BMD) at 52 weeks of 3%. Greater gains were observed at or below the lateral flare of the stem in the metaphyseal femur.

Arthroplasty, Replacement, Hip↗
PubMed2006

Minimally invasive plate osteosynthesis in the treatment of proximal humeral fracture.

The management of fractures of the proximal shaft of the humerus has been evolving since the development of new techniques and new implants in recent years. It seems that this kind of fracture has an increasing incidence in the older, osteoporotic population. In the last 2 years, we have operated on 17 patients, with an average age of 65, who had proximal humeral shaft fractures treated by minimally invasive percutaneous osteosynthesis (MIPO) technique using the metaphyseal locking compression plate. Our study evaluated the surgical technique used and the outcome for these patients with regards to their range of movement and shoulder function. Our results showed that all the patients could achieve at least 140 masculine of shoulder abduction in the first 6 months after the operation, except for three patients who had shoulder impingement. These patients had an average Constant score of 76.8. All fractures had bony union at 6 months, except one, which was probably due to poor reduction in the initial operation. Another complication that we encountered was radial nerve neuropraxia. The ways to prevent these complications are discussed. In conclusion, MIPO fixation using the metaphyseal locking compression plate is a good option for the management of proximal humeral shaft fractures. It provides early functional recovery, but we had to pay special attention to some of the surgical details in order to minimise complications.

Adult↗
PubMed2001

Histology of Kashin-Beck lesions.

There are few papers in existence describing the histopathology of Kashin-Beck disease. The few existing papers mention chondronecrosis within the epiphyseal primodium and metaphyseal cartilage. In the present study, two series of samples were available for histology: supernumerary fingers removed from young subjects and intra-articular bodies collected in more advanced cases of the disease. The prevailing characteristic of the samples is the absence of vascularisation within the proximal cartilage end plate of the phalanx associated with an alteration of the epiphyseal bone formation. These observations suggest that Kashin-Beck disease could develop from an alteration of the angiogenesis of the metaphyseal cartilage resulting in degeneration with consequent joint dysplasia, which may be associated with a decrease in growth of the diaphyseal bones.

Adolescent↗
PubMed1996

[Unstable fractures of the distal radius: a new classification].

We have carried out a retrospective study of 100 fractures of the distal radius which were classified according to 3 principal factors, namely the amount of displacement (D), the involvement of the epiphysis (E), and the degree of metaphyseal comminution (M). Each of these 3 groups was further divided into 4 levels of increasing instability. The fractures were assessed 3 months after injury. Most occurred in old patients with low grades in the DEM scale, often in association with osteoporosis and following a simple fall. Metaphyseal comminution and the degree of displacement did not correlate with the degree of osteoporosis. The highest grades of epiphyseal lesions occurred in young patients, and intact epiphyses were seen in the more osteoporotic population. The Kapandji technique, using 3 Kirschner wires, was used in 58 cases, mostly with low grades of DEM, and gave satisfactory results, but in 14% anterior carpal translation was noted. This may lead to anterior instability. External fixation was employed in 32 patients with higher grade fractures. A good anatomical result was usually obtained but the wrists were more stiff. In 7 of these patients fixation of articular fragments by wires was also needed. Reduction and immobilisation in a cast was undertaken in 7 cases with variable results. Double cortical pinning was used in 3 patients and was useful in the highest grades of displacement. We outline a scheme for treatment based on our classification.

Adolescent↗
PubMed1998

Neonatal hip: from anatomy to cost-effective sonography.

Therapeutic success in treating congenital dysplasia of the hip is associated with early diagnosis, but the specific neonatal anatomy makes screening difficult. The purpose of this study was to determine whether this specific neonatal anatomy is taken into account by current ultrasound (US) techniques. Anatomic studies were performed on 22 hips, US examinations on 7750 neonatal hips; 2370 untreated hips were reexamined at 1 month by US and at 3 months by X-ray. The transformation of the neonatal cartilaginous acetabulum into an osseous cavity is dependent on harmonious metaphyseal growth and a properly seated femoral head. Defects in the acetabular roof, together with displacement of the femoral head, cause an abnormal anatomical relationship which leads to further deformities. The described sonographic techniques give only partial information on these specific abnormalities. The sonographic monoplanar methods as used in Graf's technique, which relies largely on acetabular development, lead to difficulties in assessing posterior coverage of the femoral head and difficulties in assessing alignment of the metaphyseal weight-bearing surface with the femoral head. Combining Graf's morphological analysis with Novick's dynamic technique enables one to more accurately define the relationship of the femoral head and the acetabulum and increases the reliability and predictive value of the examination, while reducing the number of doubtful cases. This makes screening cost effective.

Cost-Benefit Analysis↗
PubMed2000

Abnormal growth plate function in pigs carrying a dominant mutation in type X collagen.

We have identified a naturally occurring, dominant mutation that causes dwarfism in domestic pigs (Sus scrofa). With a positional candidate gene approach, the dwarf phenotype was shown to be a result of a single amino acid change, G590R, in the alpha1 (X) chain of type X collagen. Type X collagen is a homotrimer of alpha1(X) chains encoded by the COL10A1 gene, which is expressed in hypertrophic chondrocytes during the process of endochondral ossification. An amino acid substitution at the equivalent position in human type X collagen, G595E, has previously been shown to cause Schmid metaphyseal chondrodysplasia (SMCD), which is a relatively mild skeletal disorder associated with dwarfism and growth plate abnormality. Consistent with the clinical phenotype of SMCD patients, radiological and histological examination of the dwarf pigs revealed metaphyseal chondrodysplasia in the long bones. Yeast-based, two-hybrid protein interaction studies and in vitro assembly experiments demonstrated that the amino acid substitution interfered with the ability of the mutated collagen molecules to engage in trimerization. This work establishes that the chondrodysplastic dwarf pigs by genetic, biochemical, radiological and histological criteria provide a valid animal model of SMCD.

Animals↗
PubMed2002

The thrust plate prosthesis in patients with aseptic osteonecrosis of the femoral head.

BACKGROUND: The thrust plate prosthesis (TPP) is an implant with a metaphyseal fixation at the proximal femur that transmits the load forces of the hip onto the femoral neck. The osseous incorporation of the TPP and the adaptation of the bone to this force transmission depend on the bone quality, which is reduced to minor vitality and stability in patients with osteonecrosis of the femoral head. Depending on the etiology of the femoral head necrosis, the TPP might lead to early failures. METHODS: In a prospective study, 63 patients with 72 cementless TPP due to femoral head osteonecrosis were examined. A clinical and radiological evaluation was performed preoperatively, 3 and 6 months postoperatively, and every year thereafter. The average follow-up period was 4.8+/-1.3 years with a minimum of 3 years. The pathogenesis of femoral head necrosis included alcoholism (n=19), subsequent to renal transplantation (n=11), during cortisone therapy of other dyscrasia (n=9), preceding a polychemotherapy (n=4), diabetes (n=3), sickle cell anemia (n=1), and idiopathic osteonecrosis (n=25). RESULTS: The Harris Hip Score increased continuously from 50.0 points beyond 79.8 points after 3 months to 86.8 points within the 1st year, and subsequently remained stable at this level. Revision was necessary in six cases (8.3%). Of these, three had an aseptic loosening of the implant: 2 cases with renal transplantation and 1 of alcoholism with an extension of the necrotic area to the seating of the TPP. The other three patients showed septic implant loosenings: 2 cases with renal transplantation and 1 of alcoholism. Radiolucent lines were found in 9 cases (12.5%), mostly in zones 1 and 2 underneath the TPP. Of these, 1 with an idiopathic osteonecrosis was assessed to be radiologically loosened. The overall failure rate was 9.7%, with a proportion of 36.4% in patients with renal transplantation. Excluding this specific patient group, the failure rate was 4.9%. CONCLUSIONS: Femoral head necrosis following renal transplantation and extension of the necrotic area into the femoral neck are contraindications for TPP. Excluding these patients, the TPP shows comparable mid-term results to cementless stemmed prostheses and supplies advantages especially for younger patients, because of its metaphyseal, bone-preserving fixation. However, evaluation of the clinical impact of the TPP in comparison with other cementless femoral stem systems requires long-term examinations in the future.

Adult↗
PubMed2003

Injectable calcium phosphate bone cement Norian SRS for the treatment of intra-articular compression fractures of the distal radius in osteoporotic women.

BACKGROUND: Distal radius fracture often presents a metaphyseal void which is more extended in elderly, osteoporotic patients. Bone graft and bone substitutes are reported to be beneficial in maintaining metaphyseal reduction. METHODS: We performed a prospective study on 52 menopausal, osteoporotic women with unstable intra-articular distal radius fractures to compare the outcome of percutaneous pinning and immobilisation in a cast for 6 weeks with that using injectable calcium phosphate bone cement (Norian Skeletal Repair System, SRS) to supplement pin and screw fixation and immobilisation in a cast for 3 weeks. All patients were reviewed 2 years (range 21-29 months) after surgery. RESULTS: Patients treated with SRS had better functional outcome, restoration of movement and grip strength ( p<0.001). In this group there was 1 mm loss of radial length, 3 degrees loss of radial inclination and 7 degrees loss of palmar tilt. In the control group radial length decreased 3 mm, radial inclination decreased 11 degrees and palmar tilt 12 degrees. Loss of reduction was significantly higher in the control group ( p<0.001). CONCLUSION: We conclude that the use of Norian SRS to supplement pin and screw fixation is effective in maintaining the reduction of unstable intra-articular distal radius fractures in osteoporotic patients and provides a better clinical outcome than percutaneous pinning.

Aged↗
PubMed2005

Palmar locking plate for treatment of unstable dorsal dislocated distal radius fractures.

INTRODUCTION: This study investigates the clinical and radiological results of open reduction and internal fixation of unstable distal radial fractures using a palmar placed interlocking plate system with no substitutes for treatment of the dorsal metaphyseal fracture void. MATERIALS AND METHODS: Nineteen patients with a mean age of 61 years (range 49-78 years) and a dorsally displaced distal radial fracture were treated using a palmar placed 2.4 mm interlocking plate system. All 17 women and 2 men were followed up according to the study protocol. Standardised radiographs in anteroposterior and lateral projection were performed before reduction and at 2, 6, 12 and 24 weeks after surgery. Radiological measurements included palmar tilt, radial inclination and radial shortening as defined by ulnar variance and intra-articular steps. Clinical assessment included active range of motion (ARM) of the wrist, pain according to a visual analogue scale (VAS), grip power, working ability, Disability of Arm, Shoulder and Hand-Score (DASH Score) and Mayo Wrist Score. RESULTS: At final follow-up after a minimum of 11 months, the palmar tilt was +1 degrees , radial inclination 19.8 degrees and ulnar variance 1.0 mm. Mean loss of palmar tilt measured 1.9 degrees , radial inclination 1.3 degrees and ulnar variance 0.4 mm. Mean wrist extension measured 58 degrees , wrist flexion 41 degrees , pronation 83 degrees and supination 84 degrees . The Mayo Wrist Score showed 21% excellent, 58% good, 16% fair and 5% poor results. CONCLUSION: The treatment of unstable, dorsally dislocated, distal radius fractures AO types A3, C1 and C2, with a palmar placed 2.4 mm interlocking plate system and without additional treatment of the metaphyseal defects showed good radiological and functional results with minimal loss of reduction.

Aged↗
PubMed2006

Salvage of proximal tibial malunion or nonunion with the use of angled blade plate.

INTRODUCTION: Single buttress plating laterally was sometimes performed by a few orthopedists to treat complex tibial plateau fractures with medial compartment involvement. However, we might encounter cases with medial compartment collapse due to such treatment. The causes of failure, the technique of the revision surgery, and the methods of prevention were investigated retrospectively. The purpose of this study was to report our clinical results of a retrospectively followed series of patients treated with blade plate fixation for proximal tibial metaphyseal nonunions and malunions which were treated with unilateral plating. MATERIALS AND METHODS: Twenty-eight patients with failed treatment of complex tibial plateau fractures due to single buttress plating laterally underwent the revision surgeries. Removal of the buttress plate, proximal tibial corrective osteotomy, and insertion of an angled blade plate medially were performed. Postoperatively, exercise of the range of motion of the knee was encouraged as early as possible. RESULTS: Twenty-five patients were followed-up for a median of 4.8 years (range, 1.2-6.8), and all fractures healed at a median of 4.0 months (range, 3.0-6.0). The proximal medial tibial angle (PMTA) was corrected to the acceptable range (80-99 degrees ) in all 25 patients (P<0.001) and knee function improved in 22 out of 25 patients (P<0.001). CONCLUSION: For clinical and biomechanical considerations, single buttress plating laterally was unsuitable for complex tibial plateau fractures with medial compartment involvement due to relatively huge compressive loads on the medial compartment. The stability provided by a few screws of the buttress plate laterally was normally insufficient. An angled blade plate could be a useful armament in the management of metaphyseal nonunion and malunions of the proximal tibia. Its better stabilization could normally provide a high success rate.

Adult↗
PubMed1999

A non-destructive technique for 3-D microstructural phenotypic characterisation of bones in genetically altered mice: preliminary data in growth hormone transgenic animals and normal controls.

A non-destructive, three-dimensional technique for microstructural phenotypic characterisation of skeletal elements in genetically altered mice is presented. Preliminary data in bovine growth-hormone transgenic animals and control littermates are shown. The technique is based on microcomputed tomography (microCT) and digital postprocessing and allows for a differential quantitative analysis of the cortical and trabecular bone compartments in the axial and peripheral skeleton. The distal femora and the first lumbar vertebral bodies of six animals were CT scanned in the axial plane with an isotropic resolution of 20 microm. The periostal surface and the marrow spaces were segmented fully automatically, and the trabecular and cortical compartments were separated interactively. After 3-D reconstruction, various regions of interest (diaphyseal, metaphyseal and epiphyseal) were selected for the analysis. The femora and vertebrae of the transgenic animals showed obvious differences in size, shape, and trabecular arrangement compared with the control animals. The total bone mass was increased by a factor of two to three, but the trabecular bone was increased much more (up to 12 times) than the cortical bone. The transgenic animals showed an increased ratio of trabecular vs cortical bone (0.90 to 1.27 vs 0.14 to 0.36 in the femoral diaphysis) and an elevated trabecular bone volume fraction (49% to 73% vs 18% to 43% in the femoral metaphysis). The mean 3-D cortical thickness was similar in the normal and transgenic animals (values between 93 microm and 232 microm in the dia- and metaphyses), but the minimal cortical thickness was lower in the transgenic animals (22 to 31 microm vs 54 microm to 110 microm in the diaphysis). The technique presented is suitable for phenotypic characterisation of bone structure in genetically altered mice.

Animals↗