Proximal Femoral Metaphysis Research Articles

Three-dimensional analysis of the proximal anterior femoral flare and torsion. Anatomic bases for metaphyseally fixed short stems design

The use of femoral stems with a short metaphyseal fixation may lead to fractures or subsidence. Such failures may be related to a mismatch between the torsions or the sagittal flares of the stem and the femur. The goal of our study was to perform a 3D analysis of the proximal metaphyseal femur anatomy with a special focus on the anterior proximal flare and torsion. Such data may help to detect the outlier patients for whom a short metaphyseal fixation should be avoided. A prospective study included 80 consecutive patients who underwent a primary cementless THA with a 3D CT-scan based pre-operative planning. A femoral frame was determined in order to analyse the proximal metaphyseal torsion and flares of the femur. The mean metaphyseal torsion was 21.6° ± 7° at 5mm above the lesser trochanter (LT) and 34.7° ± 8.8 at 15mm under LT generating a differential torsion of 13° around the LT. The mean flare index was 4.3 ± 0.9 medially, 3.7 ± 0.8 laterally, 2 ± 0.6 anteriorly and 3.1 ± 0.6 posteriorly. The anterior flare was the only flare significantly correlated to the bone density, to the age and to the femoral off-set: the higher the anterior flare index, the younger the patient, the higher the bone density and the higher the femoral offset. The anterior flare was not significantly correlated to the femoral anteversion, the metaphyseal torsion and the coronal neck-shaft angle. The proximal femoral metaphysis presents a highly variable anterior flare and torsion that may explain a mismatch between the femur and the femoral stem, consequently generating a risk of subsidence or fracture when using shortly fixed stems. Level IV.

Primary Intraosseus Xanthoma Involving the Proximal Femur in a Normolipidemic Patient: A Case Report

We report the case of a 25-year-old woman presenting with left hip pain. A lesion was found in the proximal femoral metaphysis. Benign bone tumor, such as intraosseous lipoma or liposclerosing myxofibrous tumor, was suspected based on simple radiographs and magnetic resonance images. Curettage of the lesion and bone grafting was performed. Histologic findings reflected primary intraosseous xanthoma of the proximal femur. Laboratory tests revealed the patient to be normolipidemic, while immunoelectrophoretic fractionation of lipoproteins revealed normal values for alpha, pre-beta, beta, and chylomicrons. At the one-year follow-up, there was no evidence of local recurrence. This is the first reported case of primary intraosseous xanthoma of the proximal femur in a normolipidemic patient.

Effects of Danshensu on bone formation in ovariectomized rats

Objective: To investigate the effects of Danshensu on bone formation in ovariectomized rats.Methods: Thirty female SD rats were randomly divided into three groups with 10 rats in each:blank control group, model control group and Danshensu group. The osteoporosis model was induced by bilateral ovariectomy and rats in Danshensu group were fed with Danshensu 12.5 mg·kg-1·d-1 by gavage after ostroporosis model induced. All animals were sacrificed after 90 days. The bone mineral density (BMD) of the whole body, femur and lumbar vertebra was measured by dual energy X-ray absorptiometry. The biomechanical properties of femur were measured by AG-IS mechanical universal testing machine. Serum osteocalcin and bone alkaline phosphates (BALP) levels were measured by ELISA. The number of osteoblasts of proximal femoral metaphysis was counted with light microscopy after HE staining. Results: Compared with blank control group, BMD, biomechanical properties of femur, serum osteocalcin and BALP levels and the number of osteoblasts were decreased in model control group (P<0.05 or P<0.01). While compared with model control group, BMDs of the whole body, femur and lumbar vertebra, the elastic modulus, maximum load, yield strength, breaking point load of femur, the serum levels of osteocalcin and BALP, and the number of osteoblasts were significantly improved in Danshensu group (P<0.05 or P<0.01). Conclusion: Danshensu can improve bone quality by increasing bone density, improving biomechanical properties, promoting the expression of osteogenesis-related factors, and increasing the number of osteoblasts.

Treatment Outcomes and Quality of Life after the Implantation of Modular Prostheses of the Proximal Femur in Patients with Cancer Metastases.

Surgical treatment of pathological fractures of the proximal femur with intramedullary rods produces good short-term outcomes, but after some time the fixation often becomes unstable in patients with a good prognosis and a repeat surgery is required. Modular prostheses allow for better long-term outcomes. A total of 64 surgical resection procedures for metastatic tumours of the proximal femur combined with the implantation of modular prostheses were performed at the Oncological Orthopaedics Department in Brzozów in 2010-2014. Modular prostheses were used in cases of extensive bone loss involving the proximal femoral epiphysis and metaphysis in patients in a good general condition. All patients were assessed with respect to their condition, pain intensity (VAS scale) and physical function according to the Karnofsky scale. After surgery, the patients underwent additional assessment of gait efficiency and performance with the MSTS and HHS scores. A total of 38 women and 26 men were operated on. The mean age was 66 years among the women and 69 years among the men. The follow-up period ranged from 3.6 to 1.2 years (1.8 years on average). A total of 28 GMRS (Stryker) and 36 MUTARS (Implantcast) endoprostheses were implanted. The implants were fixed with cement in 19 cases and cementless in 45 cases. All patients reported an improved quality of life after surgery. Mean pain intensity measured in a VAS scale was 3.8 and the Karnofsky physical function score was 65. Mean gait efficiency and performance assessed in the HHS and MSTS scores at 6 weeks post surgery was 75 and 20 points, respectively. All patients were able to walk and the majority could do so without crutches or using one crutch. Complications were rare. One patient experienced a massive relapse with implant loosening. There were no deep infections requiring implant removal and no implant loosening or dislocation. 1. Surgical treatment of bony metastases with modular prostheses leads to good outcomes. 2. As a surgical solution, modular prostheses considerably improve the quality of life and show slight positive progress in post-operative follow-up. 3. Complications in the form of infections, implant loosening or tumour relapse found in the patients were consistent with other literature reports.

Aluminum trichloride impairs bone and downregulates Wnt/β-catenin signaling pathway in young growing rats

Aluminum (Al) can accumulate in bone and cause bone diseases. Few studies have investigated molecular mechanism of Al-induced bone diseases. Thus, in this study, rats were orally exposed to 0 (control group) and 0.4 g/L aluminum trichloride (AlCl3) (treatment group) for 30, 60, 90 or 120 days, respectively. The Al content of femora and serum, bone histological structure, bone mineral density (BMD) of the distal and proximal femoral metaphysis and Wnt/β-catenin signaling pathway (the mRNA expressions of Wnt3a, Fzd2, LRP-5, β-catenin, Tcf4, cyclin D1 and c-Myc, the protein levels of Wnt3a and β-catenin, the activities of Fzd2 and LRP-5) in rat femora were determined on day 30, 60, 90 or 120, respectively. The results showed that the Al contents of femora and serum were increased, the BMD of the distal and proximal femoral metaphysis were decreased, the femora histological structure were disrupted, the mRNA expressions of Wnt3a, Fzd2, LRP-5, β-catenin, Tcf4, cyclin D1 and c-Myc, the protein levels of Wnt3a and β-catenin, the activities of Fzd2 and LRP-5 were all decreased in the treatment group compared with the control group with time prolonged. These results indicated that AlCl3 impaired femora by inhibiting the Wnt/β-catenin signaling pathway in young growing rats.

What's New in Pediatric Orthopaedics.

Kelly, Derek M. MD1,a; VanderHave, Kelly MD2; Martus, Jeffrey E. MD3 Author Information

Regional fat depots and their relationship to bone density and microarchitecture in young oligo-amenorrheic athletes

ContextVarious fat depots have differential effects on bone. Visceral adipose tissue (VAT) is deleterious to bone, whereas subcutaneous adipose tissue (SAT) has positive effects. Also, marrow adipose tissue (MAT), a relatively newly recognized fat depot is inversely associated with bone mineral density (BMD). Bone mass in athletes depends on many factors including gonadal steroids and muscle mass. Exercise increases muscle mass and BMD, whereas, estrogen deficiency decreases BMD. Thus, the beneficial effects of weight-bearing exercise on areal and volumetric BMD (aBMD and vBMD) in regularly menstruating (eumenorrheic) athletes (EA) are attenuated in oligo-amenorrheic athletes (OA). Of note, data regarding VAT, SAT, MAT and regional muscle mass in OA compared with EA and non-athletes (C), and their impact on bone are lacking. MethodsWe used (i) MRI to assess VAT and SAT at the L4 vertebra level, and cross-sectional muscle area (CSA) of the mid-thigh, (ii) 1H-MRS to assess MAT at L4, the proximal femoral metaphysis and mid-diaphysis, (iii) DXA to assess spine and hip aBMD, and (iv) HRpQCT to assess vBMD at the distal radius (non-weight-bearing bone) and tibia (weight-bearing bone) in 41 young women (20 OA, 10 EA and 11 C 18–25years). All athletes engaged in weight-bearing sports for ≥4h/week or ran ≥20miles/week. Main outcome measuresVAT, SAT and MAT at L4; CSA of the mid-thigh; MAT at the proximal femoral metaphysis and mid-diaphysis; aBMD, vBMD and bone microarchitecture. ResultsGroups had comparable age, menarchal age, BMI, VAT, VAT/SAT and spine BMD Z-scores. EA had higher femoral neck BMD Z-scores than OA and C. Fat mass was lowest in OA. SAT was lowest in OA (p=0.048); L4 MAT was higher in OA than EA (p=0.03). We found inverse associations of (i) VAT/SAT with spine BMD Z-scores (r=−0.42, p=0.01), (ii) L4 MAT with spine and hip BMD Z-scores (r=−0.44, p=0.01; r=−0.36, p=0.02), and vBMD of the radius and tibia (r=−0.49, p=0.002; r=−0.41, p=0.01), and (iii) diaphyseal and metaphyseal MAT with vBMD of the radius (r≤−0.42, p≤0.01) and tibia (r≤−0.34, p≤0.04). In a multivariate model including VAT/SAT, L4 MAT and thigh CSA, spine and hip BMD Z-scores were predicted inversely by L4 MAT and positively by thigh CSA, and total and cortical radius and total tibial vBMD were predicted inversely by L4 MAT. VAT/SAT did not predict radius or tibia total vBMD in this model, but inversely predicted spine BMD Z-scores. When L4 MAT was replaced with diaphyseal or metaphyseal MAT in the model, diaphyseal and metaphyseal MAT did not predict aBMD Z-scores, but diaphyseal MAT inversely predicted total vBMD of the radius and tibia. These results did not change after adding percent body fat to the model. ConclusionsVAT/SAT is an inverse predictor of lumbar spine aBMD Z-scores, while L4 MAT is an independent inverse predictor of aBMD Z-scores at the spine and hip and vBMD measures at the distal tibia and radius in athletes and non-athletes. Diaphyseal MAT independently predicts vBMD measures of the distal tibia and radius.

Adipose tissue-derived stem cells in the ovariectomy-induced postmenopausal osteoporosis rat model

This study investigated the efficacy of adult adipose tissue-derived stem cells in restoring bone using an osteoporotic rat model. Thirty-six female Wistar rats (250–300 g, 12 weeks) were randomized into three equal groups: SHAM group (sham-operated), ovariectomy-induced (OVX) group and OVX with stem cell injection group (OVX with stem). Femur extraction and blood sampling were performed at 5, 6, 7 and 8 weeks. The proximal femoral metaphysis was scanned by micro-CT and evaluated for changes in various histomorphometric parameters. β-catenin expression was determined using H&E and immunohistochemistry. Bone metabolism was assessed using measurements of C-telopeptide of collagen type I (CTX), osteocalcin, and bone alkaline phosphatase (BALP). There was a trend for an increase in the bone mineral density (BMD), bone volume/trabecular bone volume (BV/TV) and trabecular number (Tb.N) in the OVX with stem group as compared with the OVX group, and decrease in the OVX with stem group as compared with SHAM group. The trabecular thickness (Tb.Th) and trabecular separation (Tb.Sp) of the OVX group were increased compared with those values in the SHAM and OVX with stem group. BALP levels were higher in the OVX group as compared with that in the other two groups and osteocalcin levels were highest in the SHAM group and slightly increased in the OVX with stem group as compared with the OVX group. This study may help us gain an understanding of the role of MSCs in the pathophysiology and treatment of osteoporosis.

Kinetic examination of femoral bone modeling in broilers

Lameness in broilers can be associated with progressive degeneration of the femoral head leading to femoral head necrosis and osteomyelitis. Femora from clinically healthy broilers were dissected at 7 (n = 35, 2), 14 (n = 32), 21 (n = 33), 28 (n = 34), and 42 (n = 28) d of age, and were processed for bone histomorphometry to examine bone microarchitecture and bone static and dynamic properties in the secondary spongiosa (IISP) of the proximal femoral metaphysis. Body mass increased rapidly with age, whereas the bone volume to tissue volume ratio remained relatively consistent. The bone volume to tissue volume ratio values generally reflected corresponding values for both mean trabecular thickness and mean trabecular number. Bone metabolism was highest on d 7 when significant osteoblast activity was reflected by increased osteoid surface to bone surface and mineralizing surface per bone surface ratios. However, significant declines in osteoblast activity and bone formative processes occurred during the second week of development, such that newly formed but unmineralized bone tissue (osteoid) and the percentages of mineralizing surfaces both were diminished. Osteoclast activity was elevated to the extent that measurement was impossible. Intense osteoclast activity presumably reflects marked bone resorption throughout the experiment. The overall mature trabecular bone volume remained relatively low, which may arise from extensive persistence of chondrocyte columns in the metaphysis, large areas in the metaphysis composed of immature bone, destruction of bone tissue in the primary spongiosa, and potentially reduced bone blood vessel penetration that normally would be necessary for robust development. Delayed bone development in the IISP was attributable to an uncoupling of osteoblast and osteoclast activity, whereby bone resorption (osteoclast activity) outpaced bone formation (osteoblast activity). Insufficient maturation and mineralization of the IISP may contribute to subsequent pathology of the femoral head in fast-growing broilers.

Prognosis value of early diffusion MRI in Legg Perthes Calvé disease

PurposeTo evaluate diffusion MRI of the proximal femoral epiphysis and metaphysis as a prognosis factor in Legg Calvé Perthes (LCP) disease. MethodsThirty-one children (mean age 5.5 years, range 2.5–10.5) with unilateral LCP were included in a prospective, consecutive series. Radiographs were analysed and classified as per Herring criteriae. Mean follow-up was 19 months (range 6–30). Forty-nine MRI scans were performed at either the condensation or fragmentation stage. Apparent Diffusion Coefficient (ADC) of both the femoral epiphysis and metaphysis were measured bilaterally and ADC ratio were calculated, then compared to the Herring group. ResultsSixteen hips were rated Herring A or B, 3 Herring B-C and 12 Herring C. ADC was increased in affected hips compared to unaffected sides, both at the femoral epiphysis (P<0.001) and metaphysis (P<0.0001). ADC ratio of the femoral metaphysis was positively correlated to Herring classification: if superior to 1.63, it was associated with a bad prognosis (Herring B-C or C) (P=0.0017, sensitivity=89%, specificity=58%). Interobserver reliability of ADC measurement was excellent. The 1.63 threshold could be determined as early as the condensation stage. ConclusionsDiffusion presents several advantages including being non radiating and non invasive. It does not need contrast medium administration and it can be performed without anaesthesia. The origin of the increased ADC remains unknown. Basically, it reflects molecular changes (true diffusion) but it is also influenced by the vascular supply (pseudo-diffusion). ADC ratio could provide an early prognosis before Herring classification is applicable. Level of evidence: Level III. Prospective uncontrolled study.

Bedside Hip Ultrasonography in the Pediatric Emergency Department

We present a case of a 3-year-old girl brought to the emergency department for evaluation of limp after falling off the monkey bars 1 day prior. X-rays of the entire left lower extremity were normal with no evidence of fracture, dislocation, or effusion. Point-of-care ultrasound of the left hip demonstrated a hip effusion, which prompted further imaging, ultimately revealing an occult fracture of the left proximal femoral metaphysis. This case demonstrates the ability of point-of-care ultrasound to guide the management of patients presenting to the pediatric emergency department with musculoskeletal complaints.

Slipped upper femoral epiphysis: Outcome after in situ fixation and capital realignment technique

Background:Slipped upper femoral epiphysis (SUFE) is the gradually acquired malalignment of the upper femoral epiphysis (capital) and the proximal femoral metaphysis. SUFE is uncommon in India, and there are no previous studies on outcome and clinical characteristics of patients with SUFE from India. This study evaluates the presentation, disease associations and outcome of SUFE from a tertiary care centre in India.Materials and Methods:Twenty six consecutive children with SUFE seen over a period of 4 years were reviewed. The clinical presentations, severity of the slip, surgical interventions (n=30) were assessed. Twenty one boys and five girls with a mean age 13.1 years (range 10-16 years) were included in the study. Four children had bilateral involvement. There were 4 rural and 22 urban children from the eastern and southern states of the country. The presentation was acute in 7, acute on chronic in 5, and chronic in 14, with a mean duration of symptoms of 51 days (range 3-120 days). Slips were stable in 16 and unstable in 10 children. Two children had adiposogenital syndrome. Body mass index was high in 12 out of 23 children. Vitamin D levels were low in 20 out of 21 children, with a mean vitamin D level of 12.61 ± 5 ng/ml. Eighteen children underwent in situ pinning. Eight children underwent capital realignment.Results:Clinical outcome as assessed by Merle d’ Aubigne score was excellent in 6, good in 10, fair in 6 and poor in 1. Half of the in situ fixation patients underwent osteoplasty procedure for femoroacetabular impingement and 5 more were symptomatic. The head neck offset and α angle after in situ pinning were −1.12 ± 3 mm and 66.05 ± 9.7°, respectively and this improved to 8.7 mm and 49°, respectively, after osteoplasty. One child in the pinning group had chondrolysis. Eight patients with severe slip underwent capital realignment. Mean followup was 20.15 months. The anterior head neck offset and α angle were corrected to 6.8 ± 1.72 mm and 44.6 ± 7.0° mm, respectively. Two children with unstable slip in the capital realignment group had avascular necrosis which was diagnosed at presentation by bone scan.Conclusion:High BMI, vitamin D deficiency and endocrine disorders are associated with SUFE in India and should be evaluated as some of these are amenable to prevention and treatment. Most patients treated with in situ pinning developed femoroacetabular impingement. The early results after capital realignment procedure are encouraging and help to avoid a second procedure which is needed in a majority of patients who underwent in situ pinning.

Accurate in vitro identification of fracture onset in bones: Failure mechanism of the proximal human femur

Bone fractures have extensively been investigated, especially for the proximal femur. While failure load can easily be recorded, and the fracture surface is readily accessible, identification of the point of fracture initiation is difficult. Accurate location of fracture initiation is extremely important to understand the multi-scale determinants of bone fracture. In this study, a recently developed technique based on electro-conductive lines was applied to the proximal femoral metaphysis to elucidate the fracture mechanism. Eight cadaveric femurs were prepared with 15–20 electro-conductive lines (crack-grid) covering the proximal region. The crack-grid was connected to a dedicated data-logger that monitored electrical continuity of each line at 700kHz. High-speed videos (12,000 frames/s, 0.1–0.2mm pixel size) of the destructive tests were acquired. Most crack-grid-lines failed in a time-span of 0.08–0.50ms, which was comparable to that identified in the high-speed videos, and consistent with previous video recordings. However, on all specimens 1–3 crack-grid-lines failed significantly earlier (2–200ms) than the majority of the crack-grid-lines. The first crack-grid-line to fail was always the closest one to the point of fracture initiation identified in the high-speed videos (superior–lateral neck region). Then the crack propagated simultaneously, at comparable velocity on the anterior and posterior sides of the neck. Such a failure pattern has never been observed before, as spatial resolution of the high-speed videos prevented from observing the initial opening of a crack. This mechanism (fracture onset, time-lag, followed by catastrophic failure) can be explained with a transfer of load to the internal trabecular structure caused by the initial fracture of the thin cortical shell. This study proves the suitability of the crack-grid method to investigate bone fractures associated to tensile stress. The crack-grid method enables significantly faster sampling than high-speed cameras. The present findings elucidate some aspects of the failure mechanism of the proximal human femoral metaphysis.

Electroacupuncture Prevents Ovariectomy-Induced Osteoporosis in Rats: A Randomised Controlled Trial

Electroacupuncture (EA) treatment has been shown to increase bone mineral density (BMD) in ovariectomised (OVX) rats; however, the underlying mechanisms remain unclear. To systematically evaluate the effects of EA on OVX rats and the Wnt/β-catenin signalling pathway. Three-month-old female Sprague-Dawley rats were randomly divided into three different groups (n=10 each): sham operated control (sham operated), ovariectomy (OVX) and ovariectomy with EA treatment (OVX+EA). Rats in the OVX+EA group received 12-week EA treatments. Serum bone-specific alkaline phosphatase level (p<0.01), BMD of the proximal femoral metaphysis and the fifth lumbar (L5) vertebral body (both, p<0.05) and maximum load and energy to failure of L5 vertebral body (both p<0.01) were significantly higher in the OVX+EA group than in the OVX group. Trabecular area, trabecular width and trabecular number were significantly higher in the OVX+EA group by 66.9%, 29.2% and 30.3%, respectively, than in the OVX group (all, p<0.01). Trabecular separation was 31.9% lower in the OVX+EA group than in the OVX group (p<0.01). Quantitative real-time reverse transcription polymerised chain reaction indicated that the expressions of mRNAs for low-density lipoprotein receptor-related protein 5 and β-catenin were significantly increased in the OVX+EA group, as compared with the OVX group (p<0.01 and p<0.05, respectively). This study demonstrates that EA can prevent OVX-induced bone loss and deterioration of bone architecture and strength by stimulating the Wnt/β-catenin signalling pathway. These findings suggest that EA may bet a promising adjunct method for inhibiting OVX-induced osteoporosis in clinical settings.

MRI of the proximal femur predicts marrow cellularity and the number of mesenchymal stem cells

To determine whether the marrow conversion index (MCI) in MRI is related to the total number of mononuclear and mesenchymal stem cells (MSCs) in proximal femoral metaphysis of patients with hip osteoarthritis. Thirty-two hips of 32 consecutive patients who underwent total hip arthroplasty (THA) for hip osteoarthritis were included in this study. MRI of the hip was performed preoperatively and MCI was subsequently calculated. Three-milliliter bone marrow samples were obtained from the proximal femur during THA and the number of total mononuclear cells was determined using a hemocytometer. Colony forming unit-fibroblasts (CFU-Fs) assays of MSCs were performed by transferring a total of 2 × 10(4) mononuclear cells to each of five 60-mm plates. One week later, the numbers of colonies were counted. The total number of mononuclear cells decreased with increasing MCI. Likewise, the prevalence and total number of CFU-Fs increased with increasing number of total mononuclear cells, and decreased with increasing MCI. Our results suggest that measurement of MCI in MRI can be an objective and noninvasive method to predict marrow cellularity and the number of MSCs in patients with hip osteoarthritis.

An Adolescent Patient With Hip Pain: Slipped Capital Femoral Epiphysis

.He had a moderate antalgic gait with the left leg in external and internal rotation. He had also showed limited mobility of left hip in abduction, with no edema or crepitation and sensory or motor defi cits. The examination of the contralateral hip was unremarkable. The anteroposterior hip radiograph showed increased left hip joint space compared to the right hip (Fig. 1). A frog-leg lateral left hip radiograph demonstrated dislocated capital femoral epiphysis on the proximal femoral metaphysis (Fig. 2). He was taken to surgery with the diagnosis of slipped capital femoral epiphysis and the right femoral epiphysis internally fi xed with a single-cannulated screw under scopy guidance. Slipped capital femoral epiphysis (SCFE), also named as adolescent coxa vara, is characterized by a growth disturbance of the proximal femoral growth plate, resulting in posterior and inferior displacement of the proximal femoral epiphysis (femoral head) on the metaphysis (femoral neck) [1, 2]. It is a common hip disorder which is known to be strongly related to overweight and obesity in adolescents and children aged 9 - 16 years [1, 3]. A retrospective review of emergency department records stated that 68% of children with SCFE had body mass index above the 95th percentile mean weight for age [2]. The most frequent presenting symptoms in patients with SCFE are pain in the affected hip, groin, thigh, or

Dynamic analysis of exposure to aluminum and an acidic condition on bone formation in young growing rats

The toxic effects of exposure to aluminum (Al) in an acidic condition on bone formation in young growing rats were studied. Wistar rats were divided randomly into Al-treated group (100 mg Al 3+/L; pH 5.6) and control group (distilled water). Al-treated rats showed lower body weight, lower serum pH, higher accumulation of Al, in addition to disordered metabolism of calcium and phosphorus compared with control rats. The levels of parathyroid hormone, calcitonin, osteocalcin, procollagen carboxy-terminal propeptide and bone alkaline phosphatase were significantly lower in the Al-treated group than in the control group from days 90, 30, 60, 60 and 90, respectively. The bone mineral density of the distal and proximal femoral metaphysis was significantly lower in the Al-treated group than in the control group on days 120 and 150. These findings suggest that long-term Al exposure in an acidic condition inhibits bone formation and induces bone loss in young growing animals.

Predictors of the Need for Femoral Shortening Osteotomy During Open Treatment of Developmental Dislocation of the Hip

It is well accepted that femoral shortening osteotomy can reduce the risk of complications after open reduction of developmental dislocation of the hip (DDH), especially in older children and "high" dislocations. It remains unclear, however, at what age a child needs a femoral shortening osteotomy and what exactly constitutes a "high" dislocation. The purpose of our study was to evaluate age and femoral displacement as predictors of the need for a femoral shortening osteotomy during the open treatment of DDH. A retrospective study was performed on all hips that underwent open treatment for DDH between 2005 and 2008. In our algorithm, femoral shortening osteotomy was performed only if it was necessary to ease femoral head reduction (independent of patient age and radiographic displacement). Preoperative anteroposterior radiographs of the pelvis were used to measure the normalized superior and lateral displacement of the proximal femoral metaphysis relative to Hilgenreiner's line and the lateral edge of the triradiate cartilage, respectively. Operative reports were reviewed to determine age at the time of surgery and whether or not a femoral shortening osteotomy was performed. Our series consisted of 72 consecutive hips; mean patient age was 35.6 months (range: 16.4 to 76.0 mo). Overall, 25 of 72 hips (35%) underwent a femoral shortening osteotomy. When the proximal femur was vertically displaced greater than 30% of the pelvic width, the child was significantly more likely to need a femoral shortening osteotomy (P<0.0001, relative risk 3.6). Children older than 36 months of age were also more likely to require a shortening compared with younger children (P=0.001, relative risk 3.2). When both factors were present, the relative risk of needing a femoral shortening was 3.8 (P<0.00002). As expected, older patients (>36 mo of age) and high dislocations (superior displacement of the proximal femur >30% of pelvic width) were more likely to require a femoral shortening osteotomy. Our results may help frame expectations for both the family and the surgeon when anticipating surgical treatment for DDH. 3 (case-control study).

Preadipocyte Factor-1 Is Associated with Marrow Adiposity and Bone Mineral Density in Women with Anorexia Nervosa

Despite having low visceral and sc fat depots, women with anorexia nervosa (AN) have elevated marrow fat mass, which is inversely associated with bone mineral density (BMD). Adipocytes and osteoblasts differentiate from a common progenitor cell, the human mesenchymal stem cell. Therefore, understanding factors that regulate this differentiation process may provide insight into bone loss in AN. The objective of the study was to investigate the relationship between preadipocyte factor-1 (Pref-1), a member of the epidermal growth factor-like family of proteins and regulator of adipocyte and osteoblast differentiation, and fat depots and BMD in AN. This was a cross-sectional study. The study was conducted at a clinical research center. Patients included 20 women with AN (26.8 +/- 1.5 yr) and 10 normal-weight controls (29.2 +/- 1.7 yr). There were no interventions. Pref-1, leptin, IGF-I, IGF binding protein (IGF-BP)-2 and estradiol levels were measured. BMD of the spine and hip was measured by dual-energy x-ray absorptiometry. Marrow fat content of the L4 vertebra and femur was measured by (1)H-magnetic resonance spectroscopy. Pref-1 levels were significantly higher in AN compared with controls (P = 0.01). There was a positive correlation between Pref-1 and marrow fat of the proximal femoral metaphysis (R = 0.50, P = 0.01) and an inverse association between leptin and L4 marrow fat (R = -0.45, P < 0.05). There was an inverse association between Pref-1 and BMD of both the anteroposterior spine and lateral spine (R = -0.54, P = 0.003; R = -0.44, P = 0.02, respectively). Pref-1 is elevated in AN. Pref-1, IGF-I, IGF-BP2 and leptin are associated with marrow adiposity and BMD.

ACR Appropriateness Criteria® on Developmental Dysplasia of the Hip—Child

Developmental dysplasia of the hip (DDH) affects 1.5 of every 1,000 caucasian Americans and less frequently affects African Americans. Developmental dysplasia of the hip comprises a spectrum of abnormalities, ranging from laxity of the joint and mild subluxation to fixed dislocation. Early diagnosis of DDH usually leads to low-risk treatment with a harness. Late diagnosis of DDH in children may lead to increased surgical intervention and complications. Late diagnosis of DDH in adults can result in debilitating end-stage degenerative hip joint disease. Screening decreases the incidence of late diagnosis of DDH. Clinical evaluation for DDH should be performed periodically at each well-baby visit until the age of 12 months. There is no consensus on imaging screening for DDH. Consideration for screening with ultrasound is balanced between the benefits of early detection of DDH and the increased treatment and cost factors. In addition, randomized trials evaluating primary ultrasound screening did not find significant decrease in late diagnosis of DDH. In the United States, hip ultrasound is selectively performed in infants with risk factors, such as family history of DDH, breech presentation, and inconclusive findings on physical examination. Ultrasound for DDH should be performed after 2 weeks of age because laxity is common after birth and often resolves itself. A pelvic radiograph can optimally be performed after the age of 4 months, when most infants will have ossification centers of the femoral heads.