ABSTRACT. We report herein a case of multicentric myelolipoma in an 11-year-old beagle dog that presented with vomiting. Laparotomy demonstrated the presence of a large mass adherent to the greater omentum and multiple small white maculae in the spleen. Cytological and histological examinations revealed that the mass and maculae comprised mature adipocytes and hematopoietic elements including granulocytic, erythrocytic and megakaryocytic series in several phases of maturation and macrophages containing hemosiderin deposits, resembling bone marrow. Multicentric myelolipoma was diagnosed. This is first report of multicentric myelolipoma in a dog.

Introduction Mutilating-type rheumatoid arthritis, the most aggressive type of rheumatoid arthritis, is frequently associated with destructive cervical involvement, both at the high-cervical and subaxial levels, causing significant neurological deficit, and their natural course of the disease and the survival are discouraging. For such cases, we have been actively performing occipito-thoracic fusion since 1991. Although medical treatment for rheumatoid patients has represented a marked improvement, it could not treat all of these patients because of several reasons. Therefore, it is still important to evaluate the past treatment results. Methods We investigated the neurological improvement and prognosis in 51 mutilating-type rheumatoid arthritis patients who underwent occipito-thoracic fusion between 1991 and 2010. The neurological status was evaluated using modified Ranawat classification; class IIIB was subdivided into IIIBa (able to sit upright) and IIIBb (bedridden). Results The preoperative neurologic status was IIIBa in 19 patients and IIIBb in 17 patients. 15 of the 19 patients with class IIIBa improved to being able to walk (79 %), whereas only 3 of the 17 patients with class IIIBb improved to being able to walk (18 %) after surgery. Of the 51 patients, 28 died during follow-up; the mean age at death was 67.2 years. The postoperative 5-and 10-year survival rates were 60.3 and 26.4 %, respectively. Conclusion The neurological improvement and prognosis after surgery was poorer in class IIIBb patients than in the other patient groups. Occipito-thoracic fusion can improve the neurological symptoms and prognosis. However, early surgical intervention is recommended, before a patient becomes bedridden (class IIIBb).

Introduction The natural history of cervical spine lesions in rheumatoid arthritis (RA) is variable. We have actively performed occipito-thoracic fusion for severe destructive rheumatoid cervical disorders and reported its clinical results and complications. In our previous study, the most frequent complication was the adjacent-level failures caused by the fragile spine. The objective of this study was to determine risk factors for adjacent-level failures after occipito-thoracic fusion. Materials and Methods Subjects were 35 RA patients (31 females and 4 males) who underwent occipito-thoracic fusion using RRS Loop Spinal System Ò (Robert Reid Inc. Tokyo, Japan), and the incidence and characteristics of adjacent-level failures were investigated. Furthermore, the adjacent-level failures were divided into two types according to their levels, fracture at the lowest level of the fusion area and that at the level inferior to the fusion area, and the characteristics of each type were evaluated. Results and Conclusion Nine (26 %) of 35 patients suffered adjacent-level failures (10 vertebral fractures). Adjacent-level failures occurred when the distance of fixation was ''O-T4'' or longer. The long fusion might cause adjacentlevel failures due to greater mechanical stress. Seven fractures occurred at the lowest level of the fusion area, and all of them were cured without symptoms by conservative treatment. Three fractures occurred at the level inferior to the fusion area, and one of them needed additional surgery due to sudden paraplegia resulting from collapse of the adjacent vertebra. After occipito-thoracic fusion, burst fractures at the level inferior to the fusion area might cause sudden paraplegia, and therefore a careful observation should be required for patients with these fractures.

A prospective radiographic study.The purpose of this study was to analyze whether a novel skull clamp positioning system and technique is useful for obtaining good, quantitative cervical sagittal alignment during posterior cervical surgery.Different surgical procedures depend on cervical spine positioning. However, maneuver of the device and cervical position depends on the skill of the operator.This study included 21 male and 10 female patients with cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament of the cervical spine, undergoing posterior cervical surgery using the novel skull clamp positioning system. The average patient age was 68.6 years (range: 56–87 years). The novel system has a scale to adjust the neck position and to enable intended cervical sagittal alignment. First, the patient was placed on the operating table in the prone position with preplanned head–neck sagittal alignment (neutral position in general). The head was rotated sagittally, and the head was positioned in the military tuck position with the novel device that was used to widen the interlaminar space. After completing the decompression procedure, the head was rotated again back to the initial preplanned position. During this position change, the scale equipped with the device was useful in determining accurate positions. The C0-C1, C0-C2, C1-C2, C2-C7, and C0-C7 angles were measured on lateral radiographs taken pre-, intra-, and postoperatively.This novel system allowed us to obtain adequate, quantitative cervical sagittal alignment during posterior cervical surgery. There were no clinically significant differences observed between the pre- and postoperative angles for C1-C2 and C2-C7.Sagittal neck position was quantitatively changed during posterior cervical surgery using a novel skull clamp positioning system, enabling adequate final cervical sagittal alignment identical to the preplanned neck position.