Osteonecrosis in systemic lupus erythematosus: Systematic insight from the epidemiology, pathogenesis, diagnosis and management.

Osteonecrosis (ON) is one of the serious and well recognized complicationscausing severe pain and disability in patients with systemic lupus erythematosus (SLE), and its manifestation and pathogenesis are only partially understood. This review provide an update of the recent progress in etiology, pathogenesis, diagnosis, and treatment of systemic lupus erythematosus related osteonecrosis (SLE-ON). Despite the concomitant use of corticosteroids, alcohol and obesity, the dysregulated immune micro-environment and the complex pathogenesis of SLE synergistically play important roles in the development of ON. Osteonecrosis of femoral head (ONFH) is the most often involved joint in SLE. The current classification and staging system of ONFH is based on imaging techniques, particularly relating to MRI and CT, for the identification and quantification of necrotic lesions. For SLE-ONFH patients, both SLE specific clinical symptoms and ONFH imaging findings should be comprehensively evaluated. Even though advances concerning bone grafting and arthroplasty procedures have resulted in improved clinical outcomes, early pharmacological treatment at the pre-collapse stage may prevent joint collapse and reduce the joint arthroplasty rate, and this needs to be accounted. Although some progress has been made, considerably more research is needed before we fully understand SLE-ONFH. Future treatments of SLE-ONFH may involve genetic or cell-based therapies that target potential biomarkers, and this will lead to effective measures for saving thefunction of hip joint and preventing osteonecrosis.

Avascular necrosis of the femoral head in patients treated for leukaemia. Assessment of the need for a diagnostic protocol. / Necrosis avascular de cabeza femoral en pacientes tratados de leucemia. Evaluación de la necesidad de un protocolo diagnóstico.

OBJECTIVE: To evaluate the incidence of avascular necrosis of the hip in leukaemia patients treated in our hospital with high doses of corticosteroids in order to evaluate the necessity for an early detection protocol. MATERIAL AND METHODS: Observational-descriptive and retrospective study from 2005 to 2016 of 253 patients diagnosed with paediatric leukaemia. Patients with musculoskeletal pathology were identified and patients with avascular necrosis were analysed. RESULTS: A total of 26 patients (10%) had musculoskeletal symptoms. Three patients with avascular necrosis (1.2%) were analysed. One girl, 7 years old, was treated conservatively with traction - suspension and discharge. Two boys, an 11 and a 15.4 year-old,who developed graft-versus-host disease secondary to bone marrow transplantation, and whose treatment included high doses of corticosteroids, developed avascular necrosis of the hip. One was treated with bisphosphonates and forage and the other ended up with a total hip arthroplasty. DISCUSSION: The occurrence of musculoskeletal symptoms during the treatment of leukaemia is different according to the bibliographic series (0.43 -12.6%). Some authors observe an increased risk in female patients between the ages of 10 and 17. A retrospective study reveals that there is a delay of 3.9 months in the diagnosis of CAP since the onset of pain. Other authors relate NAV to loading joints, age and high doses of corticosteroids. CONCLUSION: Based on the low incidence of avascular necrosis of the hip in our 14-year-old population treated for leukaemia, the creation of diagnostic protocols seems not to be necessary. However, close monitoring of patients with potential risk factors recognized in the literature, is advisable.

Positron emission tomography-computed tomography in the assessment of viability of femoral head in acetabular fractures.

PURPOSE: The aim of this study was to use positron emission tomography-computed tomography (PET-CT) imaging as a tool for assessment of viability of femoral head in acetabular fractures and help in early detection of complications like avascular necrosis (AVN) of the femoral head. METHODS: In our study PET-CT was done pre-operatively and six weeks postoperatively in 31 patients who underwent open reduction and internal fixation (ORIF) of acetabular fractures and fracture-dislocations. There were 26 male and five female patients who were treated in our institute between January 2009 and July 2010. Patients were subsequently followed up with plain radiographs for a mean period of 3.8 years and minimum of two years. RESULTS: Although seven out of 31 patients showed avascularity of the femoral head on PET-CT in the pre-operative period, only two patients progressed to AVN at final follow up, whereas the other five patients regained the vascularity at the end of six weeks. There was no statistically significant correlation between vascular status on pre-operative scan and the presence of AVN on final follow-up radiograph. There was a significant correlation between avascularity of the femoral head on the sixth week PET-CT and AVN in the final radiograph. CONCLUSION: PET-CT seems to be useful as a prognostic investigation in the assessment of the vascular status of the femoral head following injuries around the hip. Both pre-operative and postoperative imaging are necessary to understand the time-dependent changes in blood flow following injury.

Diagnostic performance of MR imaging in the assessment of subchondral fractures in avascular necrosis of the femoral head.

OBJECTIVE: A prospective study was conducted to determine the accuracy of routine magnetic resonance (MR) imaging in correctly identifying subchondral fracture in avascular necrosis of the femoral head without apparent focal collapse on standard radiographs. MATERIALS AND METHODS: Spiral computed tomography (CT) with coronal and sagittal reformations and routine MR imaging with spin-echo T1WI and fat-suppressed spin-echo T2WI coronal, axial, and sagittal images were performed in 28 hips of 25 patients (M/F = 20:5; age 16-76 years) suffering from early-stage avascular necrosis of the femoral head on standard radiographs. The MR images were reviewed by a musculoskeletal radiologist and a general radiologist in blinded fashion. Using CT as the standard of reference, the accuracy of MR imaging in diagnosing subchondral fractures in avascular necrosis was evaluated. RESULTS: When the diagnoses of the two readers were compared with each other, only 16 of the 28 diagnoses (57.5%) agreed. Seventeen of the 28 MR imaging readings (60.7%) made by the musculoskeletal radiologist and 15 of the 28 (53.5%) made by the general radiologist agreed with those of the CT standard. False-positive diagnosis (that is, diagnosis of fracture when no fracture could be seen on CT) was more common than false-negative diagnosis. CONCLUSIONS: The accuracy of routine MR imaging in the evaluation of subchondral fracture is not satisfactory. False-positive diagnosis is not uncommon. Interpretation of routine MR imaging readout should be guarded.

Femoral head osteonecrosis: volumetric MRI assessment and outcome.

Effective treatment of femoral head osteonecrosis (FHON) requires early diagnosis and accurate assessment of the disease severity. The ability to predict in the early stages the risk of collapse is important for selecting a joint salvage procedure. The aim of the present study was to evaluate the outcome in patients treated with vascularized fibular grafts in relation to preoperative MR imaging volumetry. We studied 58 patients (87 hips) with FHON. A semi-automated octant-based lesion measurement method, previously described, was performed on the T1-w MR images. The mean time of postoperative follow-up was 7.8 years. Sixty-three hips were successful and 24 failed and converted to total hip arthroplasty within a period of 2-4 years after the initial operation. The rate of failures for hips of male patients was higher than in female patients. The mean lesion size was 28% of the sphere equivalent of the femoral head, 24+/-12% for the successful hips and 37+/-9% for the failed (p<0.001). The most affected octants were antero-supero-medial (58+/-26%) and postero-supero-medial (54+/-31%). All but postero-infero-medial and postero-infero-lateral octants, showed statistically significant differences in the lesion size between patients with successful and failed hips. In conclusion, the volumetric analysis of preoperative MRI provides useful information with regard to a successful outcome in patients treated with vascularized fibular grafts.

[Early contrast-enhanced MR imaging assessment of femoral head viability after femoral neck fracture]. / Evaluarea precoce a viabilitatii capului femural in fractura de col femural prin RMN cu substanta de contrast.

AIMS: To evaluate the use of MR imaging, before and after i.v. administration of Magnevist, for assessing the femoral head perfusion after femoral neck fracture. Evaluation of femoral head viability is important because the outcome of internal fixation is adversely affected by the development of capital osteonecrosis. METHODS: We performed MRI of the femoral head in 48 hours of injury, on 10 patients with femoral neck fracture. Five patients underwent MR imaging of the hip utilizing fat-suppressed (STIR) sequences and the others, T1-weighted spin-echo sequences before and after i.v. contrast administration. MR findings were correlated with radiographic follow-up for at least 12 months. RESULTS: Radiographic follow-up showed femoral head osteonecrosis in two patients. On contrast-enhanced MR images of these patients, the femoral head did not enhance and was lower in signal intensity than were the enhancing femoral shaft and neck distal to the fracture and the enhancing femoral head on the unaffected side. In the patients with persistent perfusion, contrast-enhanced MR images showed a uniform increase in signal intensity in the femoral shaft and neck as well as the femoral head; the femoral head on the fractured side showed contrast enhancement similar to that on the healthy side. CONCLUSIONS: These preliminary results indicate that contrast-enhanced MR imaging may be useful for noninvasive evaluation of femoral head perfusion after femoral neck fracture. MR findings also may aid the clinician in deciding between joint-preserving therapy and hip arthroplasty.

Accuracy of Medicare claims data for rheumatologic diagnoses in total hip replacement recipients.

This analysis was performed to examine whether Medicare claims accurately document underlying rheumatologic diagnoses in total hip replacement (THR) recipients. We obtained data on rheumatologic diagnoses including rheumatoid arthritis (RA), avascular necrosis (AVN), and osteoarthritis (OA) from medical records and from Medicare claims data. To examine the accuracy of claims data we calculated sensitivity and positive predictive value using medical records data as the "gold standard" and assessed bias due to misclassification of claims-based diagnoses. The sensitivities of claims-based diagnoses of RA, AVN, and OA were 0.65, 0.54, and 0.96, respectively; the positive predictive values were all in the 0.86-0.89 range. The sensitivities of RA and AVN varied substantially across hospital volume strata, but in different directions for the two diagnoses. We conclude that inaccuracies in claims coding of diagnoses are frequent, and are potential sources of bias. More studies are needed to examine the magnitude and direction of bias in health outcomes research due to inaccuracy of claims coding for specific diagnoses.

[Assessment of tissue microcirculation in patients with aseptic necrosis of femur heads in systemic lupus erythematosus (SLE)]. / Otsenka tkanevoi mikrotsirkuliatsii u bol'nykh s asepticheskim nekrozom golovok bedrennykh kostei pri sistemnoi krasnoi volchanke.

AIM: To study microcirculation in the tissues above the hip joints with and without aceptic necrosis of the femur head for diagnosis of necrosis stages. MATERIALS AND METHODS: 22 SLE patients were examined for blood flow above the region of affected and intact (control) hip joints using clearance of Xe-133 from the intratissue deposit. Basal circulation and factors of its regulation were investigated with laser dopplerflowmetry. RESULTS: Effective skin blood flow above the hip joints with necrosis stage I significantly differed from that of the control. Basal skin blood flow above the hip joints in suspected stage I of aceptic necrosis differed significantly from the control and that in stage II osteonecrosis. CONCLUSION: The study of tissue microcirculation above the hip joints in SLE patients with aceptic necrosis of the femur heads allows making diagnosis both at early and late stage of osteonecrosis.

Intraoperative assessment of femoral head vascularity after femoral neck fracture.

OBJECTIVES: To develop an intraoperative technique to predict the development of avascular necrosis after internal fixation of femoral neck fractures. DESIGN: Prospective study. SETTING: All patients were treated at the same hospital. PATIENTS/PARTICIPANTS: Sixty-four patients who presented for internal fixation of a femoral neck fracture were enrolled in the study. INTERVENTION: A 2.0-millimeter drill was used to assess the presence and character of bleeding from the femoral head at open reduction and internal fixation of a femoral neck fracture. MAIN OUTCOME MEASUREMENTS: Patients were evaluated postoperatively by history, examination, and roentgenography for the development of avascular necrosis of the femoral head fragment. A minimum two-year follow-up with radiography was required for entry into the study, with an average follow-up of 3.2 years. RESULTS: None of the fifty-six patients with bleeding from the drill holes in the femoral head fragment developed avascular necrosis. Eight of eight patients with no bleeding after reduction developed avascular necrosis. There were no infections or nonunions. CONCLUSIONS: Intraoperative drilling of the femoral head is a highly sensitive and specific predictor for the development of avascular necrosis after femoral neck fractures.

Gadolinium-enhanced MR imaging of pediatric patients after reduction of dysplastic hips: assessment of femoral head position, factors impeding reduction, and femoral head ischemia.

OBJECTIVE: We describe gadolinium-enhanced MR imaging of position and vascular enhancement of the femoral head in pediatric patients who have undergone reduction of hip dislocation. SUBJECTS AND METHODS: Within 24 hr of hip reduction and spica casting, we performed 25 gadolinium-enhanced MR studies in 18 infants and young children (15 girls, three boys) with 23 dysplastic hips. All but two patients underwent closed reductions. We evaluated intraoperative arthrograms for obstacles to reduction and subsequent radiographs for avascular necrosis. RESULTS: MR images showed that all femoral heads were in their respective acetabula, but several structures interfered with concentric reduction. Obstacles to reduction included a pulvinar (n = 16), infolding of the capsule (n = 9), interposition of the labrum (n = 2), and a hypertrophied ligamentum teres and transverse ligament (n = 2). All 50 femoral heads showed enhancement: 35 normally, 10 homogeneously but less than on the contralateral femoral head or the ipsilateral greater trochanter, and five with areas of focally decreased enhancement. Hips that showed decreased enhancement had undergone greater degrees of abduction (r = .38, p < .01). CONCLUSION: Gadolinium-enhanced MR imaging can reveal abnormalities of hip position and proximal femoral epiphyseal and physeal vascularity that can occur after hip reduction. Abnormalities of enhancement were more frequent in patients who had greater femoral abduction. The effect of decreased epiphyseal vascular enhancement is still uncertain.

[Femur head necrosis in the adult. Diagnosis, therapy, legal aspects for insurance medicine]. / Hüftkopfnekrose des Erwachsenen. Diagnostik, Therapie, versicherungsrechtliche Aspekte.

Early recognition and adequate therapy of necrosis of the head of the femur in adult patients in increasingly gaining importance since they considerably influence the permanent loss of function and reduction of the earning capacity of people of working age. Presently, MRT examination is the most conclusive method for the early stage of necrosis of the head of the femur. After the introduction of microsurgical methods, new therapeutic measures for avascular necrosis of the head of the femur are available, apart from conventional surgical methods to relieve the necrotic areas and the so-called metabolic irritation drilling. Direct vascular-supply, autologous, heterotopic, corticospongiose transplants in the necrotic head of the femur are suited to re-establish circulation in the necrotic area. This involves a considerable operative scope of work.

Acute fracture of the femoral neck: assessment of femoral head perfusion with gadopentetate dimeglumine-enhanced MR imaging.

OBJECTIVE: Evaluation of the perfusion and viability of the femoral head after fracture of the femoral neck is important because the outcome of conservative treatment or joint-preserving surgery is adversely affected by the development of capital osteonecrosis. We evaluated the use of MR imaging, before and after IV administration of gadopentetate dimeglumine, for assessing perfusion of the femoral head in 13 patients with acute fracture of the femoral neck. SUBJECTS AND METHODS: Multiecho (1600/30-240 [TR/TE]) MR images were obtained before contrast administration and gradient-echo (315/14, 90 degrees flip angle) MR images were obtained both before and after contrast administration. MR findings were correlated with findings on superselective digital subtraction angiograms of the vessels supplying the femoral head and with clinical-radiographic follow-up for at least 12 months. RESULTS: Digital subtraction angiography showed impaired blood supply to the femoral head in five patients. On contrast-enhanced MR images of these patients, the femoral head did not enhance and was lower in signal intensity than were the enhancing femoral shaft and neck distal to the fracture and the enhancing femoral head on the unaffected side. In the patients with persistent perfusion, contrast-enhanced MR images showed a uniform increase in signal intensity in the femoral shaft and neck as well as the femoral head; the femoral head on the fractured side showed contrast enhancement similar to that on the healthy side. CONCLUSION: These preliminary results indicate that contrast-enhanced MR imaging may be useful for noninvasive evaluation of femoral head perfusion after fracture of the femoral neck. MR findings also may aid the clinician in deciding between joint-preserving therapy and hip arthroplasty.

[Osteochondrosis deformans coxae juvenilis (Legg-Calvé-Perthes disease) in the MR tomogram: diagnosis and follow-up assessment correlated with x-rays and skeletal scintigraphy]. / Die Osteochondrosis deformans coxae juvenilis (Morbus Legg-Calvé-Perthes) im MR-Tomogramm: Diagnose und Verlaufsbeurteilung in Korrelation zu Röntgen und Skelettszintigraphie.

23 children with Legg-Perthes' disease (25 affected hips) were prospectively evaluated via MRI, bone scintigraphy and conventional radiography both at first presentation and during follow-ups. For the early diagnosis of LCPD MRI was similar as sensitive as isotope bone scan and more precise than conventional radiography. The extent of the necrotic area within the epiphysis could be better assessed by MRI than by conventional radiography. Providing a more detailed depiction of bone marrow and soft tissues MRI showed exactly the position and contour of the femoral head including the femoral and acetabular cartilage. The loss of containment of the femoral head could be diagnosed earlier by MRI than by conventional radiography. A system of staging of LCPD oriented towards the pathogenesis of the disease was possible with MRI in school age children, at least when comparing the tomograms with earlier studies. Scintigraphy was the most reliable imaging technique to determine the onset of revascularisation.

[Acute hip pain in the adult--assessment by magnetic resonance tomography]. / Der akute Hüftschmerz des Erwachsenen--Abklärung durch MR-Tomographie.

Using the modern cross-sectional imaging technique of MRI, significant improvement has been achieved in the early diagnosis of acute hip diseases, such as avascular femoral head necrosis, transient osteoporosis, coxitis, and tumors, the demarcation of which can be seen by MRI. Studies with MRI in patients with transient osteoporosis have revealed three stages during the clinical course. The focal stage is similar to femoral head necrosis, but always without the typical sclerotic rim. To obtain complete remission, transient osteoporosis only requires immobilization. There are difficulties in diagnosing infected and neoplastic processes.

Avascular necrosis of the femoral head: morphologic assessment by MR imaging, with CT correlation.

To better understand the morphologic appearance of avascular necrosis (AVN) of the femoral head on magnetic resonance (MR) images (1.5 T) and computed tomographic (CT) scans, the records of 21 lesions were reviewed retrospectively. All MR imaging studies included T1-weighted images (T1WI) (repetition times [TR] of 400-1,000 msec, and echo times [TE] of 20-25 msec), and 15 included T2-weighted images (T2WI) (TR = 2,000-2,500 msec; TE = 60-80 msec). MR signal features of the lesions were compared with features on the corresponding CT scans. Abnormalities in the superoanterior aspect of the femoral head were noted on both image types in all 21 lesions but were more obvious on MR images in two. A characteristic margin of peripheral sclerosis seen on CT scans in 95% (20 of 21) of lesions corresponded to a line of low intensity on MR images. Fractures complicating AVN were seen in eight lesions at CT scanning. On T1WI, fractures were not clearly delineated. On T2WI, fractures were of high intensity but were depicted less clearly than on CT scans. Central signal intensity of the lesions on T1WI correlated with the presence or absence of fracture: 88% (seven of eight) of the lesions with fractures appeared less intense than fat, compared with only 8% (one of 13) of lesions without fractures (P less than .005). While MR imaging is a sensitive method for early diagnosis of AVN, CT scanning can more accurately identify fractures and is thus important for staging.

A quantitative assessment of femoral head activity using 99Tcm -polyphosphate and a computer data collection system.

Abnormal femoral head activity in Legg-Calve-Perthes' disease has been measured using 99Tcm -polyphosphate and a gamma camera/computer data collection system. A reference point on the data matrix, which is unaffected by the diease, is used for deriving comparative uptake ratios in each femoral head. The reference point remains unaltered after surgical procedures or short intervals between follow-up studies. Early abnormality can be measured in both unilateral and bilateral femoral head pathology.

Bone trauma and related benign disease: assessment by bone scanning.

The radionuclide investigation of skeletal trauma in the past was confined generally to scintimetry and an occasional bone scan. The development of improved radiopharmaceuticals, including 99mTc-labeled compounds with their enhanced sensitivity, and the refinement of imaging devices offering superior resolution and speed have allowed a more detailed assessment of conditions resulting from trauma. Practical approaches to the diagnosis of subtle bone injury resulting in stress fracture, the differentiation between delayed healing and nonunion, and early recognition of avascular necrosis and osteomyelitis are now available. The changing pattern of radionuclide uptake in bone following damage by radiation and other abnormalities as a consequence of trauma also can be easily studied.