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PubMed1982

The radiological spectrum of fibrodysplasia ossificans progressiva.

The radiographic manifestations of nine South African patients with fibrodysplasia ossificans progressiva (FOP) have been analysed in detail. In three of these individuals, a 10--15 year follow-up was available. The condition usually presents before the age of 5 years; in one infant, abnormal calcification was demonstrated at 9 months. The disorder is remorselessly progressive but the hands, diaphragm and viscera are spared. Ossification in ligaments at the site of their attachment to long bones produces a 'pseudo-exostosis' appearance. Tethering of the shafts of long bones and growth at the proximal metaphyses can result in dislocation of shoulder and hip joints. In the hip joint the sloping configuration of the acetabular roof is produced by normal growth at the proximal metaphyseal end of the tethered femur. Calcification in periarticular tissues, together with bony and fibrous ankylosis, contributed to joint fixation. A similar process of growth inhibition leads to disparity in size between the bodies of the cervical vertebrae and their posterior appendages. It is concluded that apart from the developmental abnormality in the great toes, the skeletal changes in FOP are the consequence of soft tissue ossification and that the condition is not a primary bone dysplasia.

Arthrography↗
PubMed2001

A minimally invasive medial approach for proximal tibial fractures.

Numerous techniques have been described for MIPPO (minimally invasive percutaneous plate osteosynthesis) for metaphyseal or combined metaphyseal-articular fractures of the proximal tibia. Surgical management is often complicated by the initial soft tissue damage, malalignment, remaining instability, or infection. In this prospective cohort study, we describe the diagnostic procedures vital for preoperative planning. These include plain radiographs and CT scans in case of articular fracture components. The techniques for temporary stabilization and definitive fracture care using 4.5 mm DCP, LC-DCP, and LISS (Less Invasive Stabilization System) by limited medial incisions are described in a stepwise protocol. From 1996 to 1998, six fractures in six patients were studied. According to the AO classification, there were four type 41 fractures and two type 42 fractures. One patient died of ARDS. All patients had an intact medial soft tissue coverage allowing a medial approach. One patient developed a compartment syndrome, which was addressed by lateral dermato-fasciotomy prior to osteosynthesis. A LISS was used in three patients. The only complication related to surgery was in a patient with a four-part fracture with lateral comminution and a dislocated postero-medial fragment, which was reduced and buttressed with a short posteromedial 3.5 mm small fragment plate. This patient developed a deep, intraarticular infection, which was successfully treated with revision surgery; the implants were left in situ. At her latest follow-up at 18 months, she had a range of motion of 0/10/110, was back at work, and able to participate in recreational sports. The average time to healing was between 12 and 20 weeks postoperatively. There was no delayed healing, pseudarthrosis, recurrent fracture or late infection. None of the cases needed bone grafting. At the most recent follow-up, all patients were bearing full weight without walking aids. All cases achieved a neutral alignment and satisfactory range of movement. Though further data are needed we have sound reason to propagate a single medial approach and minimally invasive osteosynthesis as a sufficient and subtle technique for stabilization of these complicated fractures.

Adult↗
PubMed2003

An injectable calcium phosphate cement as a bone-graft substitute in the treatment of displaced lateral tibial plateau fractures.

In the treatment of displaced tibial plateau fractures, filling the resultant metaphyseal defect is essential for maintaining reduction. This study reports on 14 patients with an average age of 53 (range 34-63) years who sustained such a fracture and whose tibial defect was augmented with an injectable calcium phosphate cement under arthroscopic and fluoroscopic control. Eight fractures were treated with subcortical percutaneous screw fixation, plates were used in four cases and two fractures were treated with bone cement only. Full weight-bearing was allowed after 6-12 weeks. At the last follow-up which averaged 28 (range 18-47) months, the reduction achieved at the index operation was not altered in any of the patients except one. Most patients recorded little or no pain with an average VAS score of 1.2 (0-3.4). Ten patients had no limitation of their walking distance. Patient satisfaction was good or excellent in 12 cases. Flexion averaged 140 degrees (range 130-150 degrees ) and extension was unlimited in 13 patients. The Lysholm knee score averaged 80 and the Knee Society score 180 (range 127-195). In our opinion the injectable calcium phosphate cement used here is a promising alternative for filling metaphyseal defects in the treatment of displaced tibial plateau fractures.

Adult↗
PubMed2001

Imaging of growth disturbance in children.

Growth disturbance of the long bones in children is frequently post-traumatic but also occurs because of physeal, epiphyseal, or metaphyseal ischemia. The imaging features of growth arrest depend more on the anatomic site involved than on the cause. The physes of the distal tibia and femur and proximal tibia are disproportionately at risk because of their complex geometry. The central undulation in the distal femur and the bump in the anteromedial physis (Kump's bump) in the distal tibia are the sites of initial physiologic closure and the most frequent areas of premature fusion. The MR imaging features of growth disturbance are characteristic. T1-weighted images show low signal intensity GRL and variable signal intensity bony bridges. On GRE sequences, a bridge appears as low signal intensity interruption in the otherwise high signal intensity physeal cartilage. Physeal widening on GRE and T2-weighted images implies physeal dysfunction without bridge formation. Proton density and T2-weighted images best reveal associated metaphyseal and soft tissue changes. Regardless of the cause, MR imaging exquisitely depicts cartilaginous pathology at the physis. MR evaluation should be considered in patients at high risk for growth disturbance including young children with extensive residual growth potential; those with involvement of particularly vulnerable growth plates; and those with severe, complex fractures.

Child↗
PubMedDate not supplied

Morphometric analysis of growth retardation in fetal lambs following experimental infection of pregnant ewes with border disease virus.

The onset of growth retardation was investigated in fetal lambs following experimental infection of pregnant ewes with Border Disease virus (BDV) on day 53 of pregnancy. Fetuses from control and infected ewes were harvested at weekly intervals between day 60 and day 95 of gestation and morphometric studies were completed on tibial radiographs and tibial growth cartilage metaphyseal junctions. Mean tibial areas were significantly reduced (P < 0.01) in fetuses from infected ewes at 35 and 42 days after infection and growth cartilage metaphyseal junctions were less mature in fetuses from infected ewes at 42 days after infection. Positive immunostaining for BDV antigen was demonstrated in the brains of all fetuses from infected ewes between 14 and 42 days after infection. Attempts to demonstrate BDV antigen in bone proved unsuccessful. It is concluded that intrauterine growth retardation is an early manifestation of BDV infection in lambs and that the process is initiated shortly following infection of the fetus.

Animals↗
PubMed2004

[Biphasic ceramic wedge and plate fixation with locked adjustable screws for open wedge tibial osteotomy].

PURPOSE OF THE STUDY: The aim of this radiological study was to evaluate the use of a biphasic ceramic wedge combined with plate fixation with locked adjustable screws for open wedge tibial osteotomy. MATERIAL AND METHODS: Twenty-six consecutive patients (27 knees) underwent surgery between December 1999 and March 2002 to establish a normal lower-limb axis. The series included 6 women and 20 men, mean age 50 years (16 right knees and 11 left knees). Partial weight-bearing with crutches was allowed on day 1. A standard radiological assessment was performed on day 1, 90, and 360 (plain AP and lateral stance films of the knee). A pangonogram was performed before surgery and at day 360. Presence of a lateral metaphyseal space, development of peripheral cortical bridges, and osteointegration of the bone substitute-bone interface were evaluated used to assess bone healing. The medial tibial angle between the line tangent to the tibial plateau and the anatomic axis of the tibia (beta) was evaluated to assess preservation of postoperative correction. The HKA angle was determined. RESULTS: Three patients were lost to follow-up and 23 patients (24 knees) were retained for analysis. At last follow-up, presence of peripheral cortical bridges and complete filling of the lateral metaphyseal space demonstrated bone healing in all patients. Good quality osteointegration was achieved since 21 knees did not present an interface between the bone substitute and native bone (homogeneous transition zone). The beta angle was unchanged for 23 knees. A normal axis was observed in patients (16 knees) postoperatively. DISCUSSION: Use of a biphasic ceramic wedge in combination with plate fixation with locked adjustable screws is a reliable option for open wedge tibial osteotomy. The bone substitute fills the gap well. Tolerance and integration are optimal. Bone healing is achieved. Plate fixation with protected weight bearing appears to be a solid assembly, maintaining these corrections.

Adult↗
PubMed2005

[Twenty nine shoulder reconstructions after resection of the proximal humerus for neoplasm with mean 7-year follow-up].

PURPOSE OF THE STUDY: Techniques available for shoulder reconstruction after resection of a tumor of the proximal humerus include scapulohumeral arthrodesis, humerus prosthesis with or without an allograft, inverted prostheses, and massive allografts. The purpose of this study was to review clinical and radiological outcomes in a series of 29 patients (20 men and 9 women) who underwent resection-reconstruction of the proximal humerus and to establish from these cases a decision making algorithm for therapeutic indications as a function of tumor invasion. MATERIAL AND METHODS: The tumors were 20 chondrosarcomas, five osteosarcomas, two Ewing sarcomas and one malignant hemangiopericytoma. In 17 patients epiphyso-metaphyseal or epiphyso-metaphyso-diaphyseal resection was performed with preservation of the abductor muscles (type S34A or S345A according to the Musculoskeletal Tumor Society classification). For 12 patients epiphyso-metaphyseal or epiphyso-metaphyso-diaphyseal resection was performed without preservation of the abductor muscles (type S34B or S345B). Reconstruction was achieved using a centromedullary cemented nail in one patient, scapulohumeral arthrodesis in three, a massive humerus prosthesis in 15, and composite humerus prosthesis in three and an inverted prosthesis in seven. The functional score of the Musculoskeletal Tumor Society (MSTS) and standard x-rays were used to assess outcome. RESULTS: Mean follow-up was 85 months (range 16-300). The mean MSTS score was 88% for inverted prostheses, 76% for composite prostheses, 72.6% for massive prostheses, 75% for scapulohumeral arthrodeses, 67% for massive prostheses, and 80% for cemented centromendullary nail. Five patients died from their malignant disease and one from another cause. Four patients are alive but with active disease after a mean follow-up of 108 months and 19 patients (65.5%) are alive and free of locoregional recurrence or metastasis after a mean 83.5 months. We had 28 complications. Glenohumeral instability was the most frequent (11 cases). DISCUSSION: Resection of the upper portion of the humerus should be performed to achieve cancerologically satisfactory tumor resection and enable shoulder resection, if possible, with preservation of a viable and functional abductor system. The functional outcome after such reconstruction depends on the type of bony resection, but also on the sacrifice of the rotator cuff and the deltoid muscle. In light of our experience and results in the literature, we advocate, despite the small number of cases for the different reconstructions, the following decision-making algorithm after resection of the proximal humerus without joint invasion: when the resection removes the rotator cuff and the deltoid (or the axillary nerve), there are two options: scapulohumeral arthrodesis or massive humerus prosthesis for patients who do not desire a complex therapy with a long postoperative period; when the resection preserves the rotator cuff and/or the deltoid muscle, reconstruction can be achieved with a composite (inverted or not) prosthesis with suture of the cuff tendons. We prefer the inverted composite prosthesis; if the deltoid muscle can be preserved but not the rotator cuff, the composite inverted prosthesis appears to be the most logical solution, but scapulohumeral arthrodesis can be proposed in selected cases.

Adolescent↗
PubMed1987

Epiphyseal osteosarcoma: distinguishing features from clear cell chondrosarcoma, chondroblastoma, and epiphyseal enchondroma.

In a retrospective radiologic and histologic study of 286 osteosarcomas in files of a metropolitan hospital, four patients (three men and one woman) with osteosarcomas confined to the epiphysis were identified. In this series, there were also 16 metaphyseal osteosarcomas that extended to the epiphysis with penetration through the cartilaginous growth plate, a structure that ordinarily resists tumor growth. All tumors occurred in the femoral condyle. Characteristically, all four patients had histories of knee joint pain, and three reported antecedent trauma. Radiologically, the tumors showed predominantly lytic features. Histologically, three of the tumors were osteoblastic in type, and one was mostly chondroblastic. Purely epiphyseal osteosarcoma has overlapping radiologic features with clear cell chondrosarcoma, epiphyseal chondroblastoma, and epiphyseal enchondroma. The epiphyseal osteosarcomas of the distal femur reported here were characterized by a history of symptoms localized to the knee joint itself as a consequence of their epiphyseal location and joint involvement. This is in contrast to the usual metaphyseal osteosarcomas, which present with lower thigh pain and swelling. Because osteosarcomas may present as lytic tumors confined to the epiphysis, they should be included in the differential diagnosis of such lesions.

Bone Neoplasms↗
PubMed1976

Florid and subclinical rickets among immigrant children in Glasgow.

200 Asian 300 African, Chinese, or Scottish children were examined for clinical, biochemical, and radiological evidence of vitamin-D deficiency. Among the Asians there were 10 with florid rickets and 15 with subclinical rickets. Among the African, Chinese, and Scottish children there were no cases of florid rickets and only 7 cases of subclinical rickets (3 African, 3 Chinese, and 1 Scottish). Loss of metaphyseal definition is considered to be the radiological pattern of minimal active rickets and metaphyseal bands to represent the healing stage. Serum 25-hydroxycholecalciferol concentrations were low in clinical and subclinical minimal active rickets although there was some overlap with the wide range found in the "normal" group. Elevated serum-alkaline-phosphatase levels alone should not be regarded as indicating vitamin-D deficiency. The continuing prevalence of rickets in Asian children and in particular among schoolchildren warrants immediate action, which is long overdue.

Africa↗
PubMed2003

The removal torque of titanium screw inserted in rabbit tibia treated by dual acid etching.

Chemical acid etching alone of the titanium implant surface have the potential to greatly enhance osseointegration without adding particulate matter (e.g. TPS or hydroxyapatite) or embedding surface contaminants (e.g. grit particles). The aims of the present study were to evaluate any differences between the machined and dual acid etching implants with the removal torque as well as topographic analysis. A total of 40 custom-made, screw-shaped, commercially pure titanium implants with length of 5 mm and an outer diameter of 3.75 mm were divided into 4 groups, 10 screws in each, and chemical modification of the titanium implant surfaces were achieved using HF and HCl/H(2)SO(4) dual acid etching. The first exposure was to hydrofluoric acid and the second was to a combination of hydrochloric acid and sulfuric acid. The tibia metaphysics was exposed by incisions through the skin, fascia, and periosteum. One implant of each group was inserted in every rabbit, 2 in each proximal tibia metaphysics. Every rabbit received 3 implants with acid etched surfaces and 1 implant with a machined surface. Twelve weeks post-surgically, 7 rabbits were sacrificed, Subsequently, the leg was stabilized and the implant was removed under reverse torque rotation with a digital torque gauge (Mark-10 Corporation, USA) (Fig. 1). Twelve weeks after implant placement, the removal torque mean values were the dual acid etched implants (24%HF+HCl/H(2)SO(4), group C) required a higher average force (34.7 Ncm), than the machined surface implants (group A) (p=0.045) (Mann-Whiteney test). Scanning electron micrographs of acid etching of the titanium surface created an even distribution of very small (1-2 microm) peaks and valleys, while machining of the titanium surface created typical microscopically grooved surface characteristics. Nonetheless, there was no difference in surface topography between each acid etched implant groups. Therefore, chemically acid etching implant surfaces have higher strengths of osseointegration than machined implant surfaces. There is less correlation between removal torque and the difference in HF volume%.

Acids↗
PubMed1993

Application of computer-based histomorphometry to the quantitative analysis of methylprednisolone-treated adjuvant arthritis in rats.

Analyses of paw edema and histomorphometry were performed on tibio-talar joints to determine arthritic pathological responses in untreated 28-day adjuvant-induced polyarthritis (AIP) rats, and to determine the drug effect on inhibiting these responses in AIP rats treated with methylprednisolone. Histomorphometric measurements were performed on regions including articular joint space, synovial tissue, articular and epiphyseal cartilage, epiphyseal and metaphyseal bone marrow, and endosteal and periosteal cortical bone surfaces. Analysis of paw edema indicated that paw volume was significantly increased in untreated AIP rats. This increase in paw volume was partially prevented in AIP rats treated with 0.3 mg methylprednisolone/kg per day, and completely prevented in AIP rats treated with the two higher dose levels (1 and 3 mg/kg per day). Histomorphometric analysis of untreated AIP tibio-talar joints showed decreased articular joint space whereas synovial tissue area increased and a minor, but significant, articular cartilage erosion area occurred. Epiphyseal growth cartilage area was decreased. Trabecular bone area in distal tibial epiphyseal and metaphyseal regions was markedly decreased whereas bone marrow area increased involving a large number of macrophages and osteoclasts. Eroded endocortical bone area was increased while cortical bone area decreased. Marked osteophyte proliferation occurred on the periosteal surface. These arthritic pathological changes were inhibited by the treatment of methylprednisolone in a dose-dependent fashion. The animals treated with the highest dose of methylprednisolone complete prevented the development of the AIP-induced pathological changes. These data confirmed qualitative histological evaluation of arthritic changes but did not correlate with the anti-edema effects of methylprednisolone (100% inhibition at 1.0 and 3.0 mg/kg, p.o.). It is suggested that quantitative histomorphometry be used to determine more precisely the AIP rat model and the effects of drugs on different histopathological features in this experimental model of arthritis in preference to paw edema which gives a more limited picture of the arthritic response.

Analysis of Variance↗
PubMed1994

Gender dependent effects of testosterone and 17 beta-estradiol on bone growth and modelling in young mice.

This study examined the effects of estrogen (17 beta-estradiol) and testosterone on the growth of long bones in male and female mice, with and without gonadectomy. Weight and nose-to-tail length were determined at 3 weeks of age at time of gonadectomy, 7 days later at the onset of hormone therapy, and throughout the treatment period. Gonadectomized mice exhibited an initial weight gain during the pretreatment period but length was unaffected. Hormone treatment altered weight gain in surgical and intact animals in a gender- and hormone-dependent manner. Estradiol enhanced weight gain in intact mice, but inhibited weight gain in ovariectomized mice. Lower doses of estradiol increased weight gain in orchiectomized mice at early time points. Testosterone increased weight in intact females and males, but not in gonadectomized mice. Estradiol increased nose-to-tail length in intact females at early time points, but inhibited length in ovariectomized females at later times, and it decreased length in intact males. Testosterone increased length in normal females and normal males. Serum Ca was unaffected by ovariectomy, but orchiectomy resulted in decreased levels. Estradiol reduced serum Ca in gonadectomized animals; serum Ca was increased by estradiol treatment in intact females. Changes in tibial bone weight, ash weight and mineral composition, and relative sizes of epiphyseal and metaphyseal bone were gender-, gonadectomy- and hormone-specific. Bone weight was greater in ovariectomized mice. Ash weight per bone was comparable, but there was an increase in Ca and P content with ovariectomy. Estradiol increased bone weight, ash content, and bone Ca and P in ovariectomized and intact females. Orchiectomy alone did not alter bone weight, ash content, or Ca and P, but orchiectomized mice were sensitive to estradiol; all parameters were increased in the orchiectomized animals treated with estradiol. Analysis of the ash content and Ca and P per mg bone, rather than per bone, demonstrated estradiol and testosterone alter net bone formation, but not the amount of mineral per unit bone. Ovariectomy increased hypertrophic cartilage. While estradiol did not alter tibial area in ovariectomized mice, it caused an increase in intact females. The total amount of growth plate cartilage in ovariectomized animals was decreased by estradiol to levels typical of intact animals due to a greater decrease in the hypertrophic cartilage in the ovariectomized mice, as well as a greater increase in metaphyseal bone area. Testosterone had no effect on these parameters in the females. Orchiectomy decreased the amount of growth plate cartilage, but increased the hypertrophic zone.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1993

Anabolic responses of an adult cancellous bone site to prostaglandin E2 in the rat.

The objects of this study were to determine: (1) the response of a non-growing cancellous bone site to daily prostaglandin E2 (PGE2) administration; and (2) the differences in the effects of daily PGE2 administration in growing (proximal tibial metaphysis, PTM) and non-growing cancellous bone sites (distal tibial metaphysis, DTM). Seven-month-old male Sprague-Dawley rats were given daily subcutaneous injections of 0, 1, 3 and 6 mg PGE2/kg per day for 60, 120 and 180 days. The static and dynamic histomorphometric analyses were performed on double-fluorescent labeled undecalcified distal tibial metaphyses (DTM). No age-related changes were found in static and dynamic histomorphometry of DTM cancellous bone between 7 and 13 months of age. The DTM of 7-month-old (basal controls) rats consisted of a 24.5 +/- 7.6%-metaphyseal cancellous bone mass, and a thick trabeculae (92 +/- 12 micron). It also had a very low tissue-base bone formation rate (3.0 +/- 7.3%/year). Exogenous PGE2 administration produced the following transient changes in a dose-response manner between zero and 60 days: (1) increased trabecular bone mass and improved architecture (increased trabecular bone area, width and number, and decreased trabecular separation); (2) increased trabecular interconnections; (3) increased bone formation parameters; and (4) decreased eroded perimeter. A new steady state with more cancellous bone mass and higher bone turnover was observed from day 60 onward. The elevated bone mass induced by the first 60 days of PGE2 treatment was maintained by another 60 and 120 days with continuous daily PGE2 treatment. When these findings were compared to those previously reported for the PTM, we found that the DTM was much more responsive to PGE2 treatment than the PTM. Percent trabecular bone area and tissue-based bone formation rate increased significantly more in DTM as compared to PTM after the 60 days of 6 mg PGE2 treatment. These observations indicate that a non-growing cancellous bone site is more responsive than growing bone site to long-term daily administration of PGE2.

Aging↗
PubMed1997

Post-mortem radiological examination in infants: evidence of child abuse?

We examined the value of post-mortem radiological examination of infants who were brought in for medico-legal autopsy. Twenty children between the age of 1 month and 15 months died under the picture of SIDS. No radiological or other signs of previous child abuse were seen in our autopsy material. A fatal case of child abuse with several metaphyseal fractures is reported. Some fractures were not visible on gross examination, but could be demonstrated by radiography and histology. In our material no association between SIDS and child abuse was found. In suspected cases of child abuse, particularly rib fractures and metaphyseal fractures should be sought. We recommend that post-mortem radiography is performed in such cases. If fractures are demonstrated, they should be verified by histologic examination.

Autopsy↗
PubMed2002

The effect of long-term methylprednisolone treatment on the femoral head in growing pigs.

The effect of long term steroid treatment on coagulation, intraosseous pressure (IOP), femoral head (FH) blood flow, and histology in the normal organism was investigated in this study in growing pigs. From 24 growing female Danish Landrace pigs from 12 litters, 12 animals daily received 100 mg methylprednisolone orally for three months. Their 12 sister pigs served as controls without steroid treatment. Prothrombin time, activated partial thromboplastin time (aPTT), fibrinogen, and antithrombin III levels were recorded in jugular venous blood. Blood flow of the hip regions was measured by means of the radioactive microsphere technique. Metaphyseal and epiphyseal IOP of the left or right proximal femur were measured. Histomorphometry of the left or right FH epiphysis was performed. Major growth inhibition was found in the corticosteroid (CS) treated group. In CS pigs, aPTT was shortened to 50% compared to control pigs. Plasma fibrinogen was higher in the CS animals. Total FH blood flow was not different while regional blood flow in the cranial subregion of the FH epiphysis was higher in the CS group. Metaphyseal and epiphyseal IOP of the proximal femur were not different in the CS animals. Histomorphometrically, cancellous bone volume (23 +/- 1% vs. 34 +/- 2%; p < 0.001) and bone turnover (10 +/- 2% vs. 55 +/- 8%; p < 0.001) of the FH epiphysis was lowerin the CS than in the control group. The FH epiphysis of the CS animals invariably showed an irregular cartilage-bone interface with cartilaginous projections into the subchondral bone mainly in its cranial part. In normal growing pigs, long term high dose CS treatment has induced a hypercoagulable state of plasma via the intrinsic pathway of coagulation, cartilaginous projections into FH subchondral bone, FH osteopenia, and reduced bone turnover. Long-term steroid treatment did not produce FH necrosis or FH IOP alterations in the immature pig model.

Animals↗
PubMed2003

Orthopedic management of vertebral and long bone fractures in patients with osteoporosis.

Because of the evolving demographics of the world's population, fracture surgeons must become experts in the treatment of fractures in osteoporotic bone. Toward this end, fracture surgeons are learning to modify the classic techniques of internal fixation to adapt them to the elderly population. Screws should be placed into the best quality of bone available, which, in most cases, is an opposing cortex. Screw fixation can be augmented using acrylic cement. When using plate fixation, stable bone contact at the fracture site is the most important factor in reducing strain in the plate. Shortening of the affected bone is advisable to achieve this contact in comminuted fractures. Plates should not be used to bridge areas of comminution in osteoporotic bone. Plates should generally be as long as is compatible with the affected bone, with screws placed as close to and as far away from the fracture site as possible. When confronted with diaphyseal fractures or fractures with metaphyseal-diaphyseal comminution, locked intramedullary nails can be used. Angled blade plates are applicable to osteoporotic metaphyseal fractures but should be used as tension band plates, which require stable load-sharing contact opposite the plate. Antiglide plating and use of tension band wires are also effective strategies for osteoporotic fractures. Finally, to reduce the morbidity of bone graft harvest and to ensure adequate volumes of graft, the use of bone graft substitutes is particularly applicable in elderly patients. All patients with evidence of osteoporosis should be started on a medical regimen to combat further bone loss that includes calcium supplementation with a prescription for antiresorptive agents, including bisphosphonates, calcitonin, or hormone replacement therapy.

Bone Transplantation↗
PubMed2000

Diversity of proximal femoral medullary canal.

To analyze the endosteal dimensions of the proximal femoral medullary canal, we studied 50 cadaver femora using computed tomography and a border detection method from 20 mm above the lesser trochanter, the osteotomy level, down to the isthmus. We documented the presence of a dense calcar septum in 96% of femora studied. In addition to mediolateral, anteroposterior, and neck-oriented dimensions, we calculated canal flare indices (CFIs) between the osteotomy level and the isthmus and metaphyseal canal flare indices (MCFIs) between the osteotomy level and the level 20 mm below the lesser trochanter midpoint to describe the shape of the endosteal cavity. With respect to the canal opening, the anteroposterior and mediolateral planes parallelled each other over the entire region as indicated by the high correlation (r = .7, P < .001) between the CFIs in these directions. The prediction of one dimension from another was unreliable in the metaphyseal region, where bone ingrowth is supposed to occur in a femoral prosthesis. The MCFI seemed to be the best parameter to distinguish the various types of proximal femoral canal shapes. We have described the variability of the proximal femoral endosteal dimensions in detail and find that the wide variation in the shape and size of the proximal femoral medullary canal means that it is almost impossible to achieve 100% cortical contact with the stem, especially in the metaphysis.

Aged↗
PubMed2000

The anatomic basis for the concept of lateralized femoral stems: a frontal plane radiographic study of the proximal femur.

We determined the range of sizes for a system of monoblock femoral prostheses that would provide adequate (a term defined in the text) fill in the frontal plane and restore femoral offset and leg length. We performed an anatomic study, based on measurements in 200 anteroposterior pelvic radiographs. If diaphyseal filling implants are to be used, 9 sizes are sufficient to obtain excellent canal filling and restoration of femoral offset in >80% of cases, assuming that the level of neck osteotomy can vary over a 1-cm range. When using metaphyseal filling implants, only a limited adjustment can be obtained from the level of neck osteotomy. A system limited to 8 sizes approximates the anatomy of the femoral canal with satisfactory precision in 73% of cases. If such a system is provided with only a single neck shaft angle for each stem size, it does not allow restoration of the biomechanical center of the hip in >67% of cases. A system of 8 sizes of 1 neck/shaft angle and a 22-mm modular head restores the anatomy in only 49% of cases. Approximating the frontal anatomy of 85% of femora with an implant filling the metaphysis requires at least 15 sizes distributed in 3 metaphyseal configurations, each supplied with 2 different neck shalt angles.

Aged↗