Objective: To compare six different parameters described in literature for estimation of pelvic tilt on an anteroposterior pelvic radiograph and to create a simple nomogram for tilt correction of prosthetic cup version in total hip arthroplasty. Design: Simultaneous anteroposterior and lateral pelvic radiographs are taken routinely in our institution and were analyzed prospectively. The different parameters (including three distances and three ratios) were measured and compared to the actual pelvic tilt on the lateral radiograph using simple linear regression analysis. Patients: One hundred and four consecutive patients (41 men, 63 women with a mean age of 31.7 years, SD 9.2 years, range 15.7-59.1 years) were studied. Results: The strongest correlation between pelvic tilt and one of the six parameters for both men and women was the distance between the upper border of the symphysis and the sacrococcygeal joint. The correlation coefficient was 0.68 for men (P<0.001) and 0.61 for women (P<0.001). Based on this linear correlation, a nomogram was created that enables fast, tilt-corrected cup version measurements in clinical routine use. Conclusion: This simple method for correcting variations in pelvic tilt on plain radiographs can potentially improve the radiologist's ability to diagnose and interpret malformations of the acetabulum (particularly acetabular retroversion and excessive acetabular overcoverage) and post-operative orientation of the prosthetic acetabulum.

Three Swainson's Blue Mountain Rainbow Lorikeets (Trichoglossus haematodus moluccanus), ranging from 6 to 8 months of age, presented with lethargy, emaciation, and progressive neurologic signs. The first one died 24 hours after the onset of clinical signs, and the other two were euthanized 10 to 14 days after the onset of progressive neurologic disease. Clinical signs in these lorikeets included head pressing, hemiparesis, seizures, obtunded mentation, weakness, and lethargy. Two of the lorikeets had hepatomegaly, and one had splenomegaly on gross examination. Histopathology revealed disseminated microgranulomas in the liver, spleen, and brain, and lymphohistocytic perivascular encephalitis and cephalic vasculitis. Electron microscopic examination of macrophages in brain lesions revealed spherical to rod-shaped prokaryotic organisms with a trilaminar cell wall. Molecular analysis revealed a novel species of Coxiella. This is believed to be the first report of a Coxiella sp. causing disease in a lorikeet.

Hibernoma is a rare benign soft tissue tumor of brown fat. Awareness of the MR imaging appearances of this lesion may allow for improved preoperative diagnosis or at least inclusion of hibernoma as a possible benign differential diagnosis prior to surgery.

The initial patient had thoracic T6 and T8 vertebra plana. Bone scan showed additional vertebral body involvement. Follow-up was available over a 3 year period. The second patient had partial collapse of T9 and, 2 years later, of C6. Subsequently extensive multifocal disease ensued and follow-up was available over 8 years. The third patient initially had L3 inferior partial collapse and 1 year later T8 involvement with multifocal disease. Follow-up was available over 3 years. The imaging findings of the three patients include partial and complete vertebra plana with a subchondral line adjacent to endplates associated with bone marrow MR signal alterations. Awareness of the imaging appearances may help the radiologist to include this entity in the differential diagnosis in children who present with spinal pathology and no history of trauma. Histopathological examination excludes tumor and infection but with typical imaging findings may not always be necessary.

A 28-year old woman presented with Léri's disease (melorheostosis) and the rare combination of complex vascular malformations and lymphatic anomalies. Multifocal melorheostosis was segmental and unilateral, located in the left axial and peripheral skeleton, fifth thoracic vertebral body, fifth rib. left upper limb and lumbosacral spine (third lumbar body to first sacral segment). Sacral involvement was associated with spinal canal stenosis. Additionally the patient had multiple nevi and had suffered from left hemiplegia since birth. Lymphangiectasia of the mesentery and thorax led to chylothorax resistant to therapy for which the patient underwent a pleuropericardiectomy. Death ensued due to respiratory failure.