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Muheremu A.,Tsinghua University | Sun Y.,Beijing Ji Shui Tan Hospital
Medical Hypotheses | Year: 2016

Patients with cervical spondylosis often present with some atypical symptoms such as vertigo, headache, palpitation, nausea, abdominal discomfort, tinnitus and blurred vision and hypomnesia. Although there are a few hypotheses about the etiology of those symptoms, none of them have provided evidence convincing enough to explain the clinical, pathological and anatomic manifestation of those symptoms. One of the more acceptable explanations is that those symptoms are the results of stimulation of the sympathetic nerves in the posterior longitudinal ligament. The clinical fact that dissection of the posterior longitudinal ligament significantly alleviates the severity of those symptoms seems like an evidence for the validity of this hypothesis. However, recent clinical studies showed that laminoplasty, which has no effect on the posterior longitudinal ligament, can achieve the similar effect. In this paper, we hypothesize that stimulation of the dura mater and spinal cord might be the cause of atypical symptoms in patients with cervical spondylosis. © 2016 Elsevier Ltd.

Carballido-Gamio J.,University of California at San Francisco | Harnish R.,University of California at San Francisco | Saeed I.,University of California at San Francisco | Streeper T.,University of California at San Francisco | And 13 more authors.
Journal of Bone and Mineral Research | Year: 2013

Hip fracture risk rises exponentially with age, but there is little knowledge about how fracture-related alterations in hip structure differ from those of aging. We employed computed tomography (CT) imaging to visualize the three-dimensional (3D) spatial distribution of bone mineral density (BMD) in the hip in relation to age and incident hip fracture. We used intersubject image registration to integrate 3D hip CT images into a statistical atlas comprising women aged 21 to 97 years (n = 349) and a group of women with (n = 74) and without (n = 148) incident hip fracture 4 to 7 years after their imaging session. Voxel-based morphometry was used to generate Student's t test statistical maps from the atlas, which indicated regions that were significantly associated with age or with incident hip fracture. Scaling factors derived from intersubject image registration were employed as measures of bone size. BMD comparisons of young, middle-aged, and older American women showed preservation of load-bearing cortical and trabecular structures with aging, whereas extensive bone loss was observed in other trabecular and cortical regions. In contrast, comparisons of older Icelandic fracture women with age-matched controls showed that hip fracture was associated with a global cortical bone deficit, including both the superior cortical margin and the load-bearing inferior cortex. Bone size comparisons showed larger dimensions in older compared to younger American women and in older Icelandic fracture women compared to controls. The results indicate that older Icelandic women who sustain incident hip fracture have a structural phenotype that cannot be described as an accelerated pattern of normal age-related loss. The fracture-related cortical deficit noted in this study may provide a biomarker of increased hip fracture risk that may be translatable to dual-energy X-ray absorptiometry (DXA) and other clinical images. © 2013 American Society for Bone and Mineral Research.

Sun Y.Q.,Beijing Ji Shui Tan Hospital | Samartzis D.,University of Hong Kong | Cheung K.M.C.,University of Hong Kong | Wong Y.W.,University of Hong Kong | Luk K.D.K.,University of Hong Kong
European Spine Journal | Year: 2011

The correction rate (CR) and fulcrum bending correction index (FBCI) based on the fulcrum bending radiograph (FBR) were parameters introduced to measure the curve correcting ability; however, such parameters do not account for contributions by various, potential extraneous "X-Factors" (e.g. surgical technique, type and power of the instrumentation, anesthetic technique, etc.) involved in curve correction. As such, the purpose of the following study was to propose the concept of the "X-Factor Index" (XFI) as a new parameter for the assessment of the correcting ability of adolescent idiopathic scoliosis (AIS). A historical cohort radiographic analysis of the FBR in the setting of hook systems in AIS patients (Luk et al. in Spine 23:2303-2307, 1998) was performed to illustrate the concept of XFI. Thirty-five patients with AIS of the thoracic spine undergoing surgical correction were involved in the analysis. Plain posteroanterior (PA) plain radiographs were utilized and Cobb angles were obtained for each patient. Pre- and postoperative PA angles on standing radiograph and preoperative fulcrum bending angles were obtained for each patient. The fulcrum flexibility, curve CR, and FBCI were determined for all patients. The difference between the preoperative fulcrum bending angle and postoperative PA angle was defined as AngleXF, which accounted for the correction contributed by "X-Factors". The XFI, designed to measure the curve correcting ability, was calculated by dividing Angle XF by the fulcrum flexibility. The XFI was compared with the curve CR and FBCI by re-evaluating the original data in the original paper (Luk et al. in Spine 23:2303-2307, 1998). The mean standing PA and FBR alignments of the main thoracic curve were 58.3° and 24.5°, respectively. The mean fulcrum flexibility was 58.8%. The mean postoperative standing PA alignment was 24.7°. The mean curve CR was 58.0% and the mean FBCI was 101.1%. The mean XFI was noted as 1.03%. The CR was significantly positively correlated to curve flexibility (r = 0.66; p < 0.01).The FBCI (r = -0.47; p = 0.005) and the XFI (r = -0.45; p = 0.007) were significantly negatively correlated to curve flexibility. The CR was not correlated to AngleXF (r = 0.29; p = 0.089).The FBCI (r = 0.97; p < 0.01) and the XFI (r = 0.961; p < 0.01) were significantly positively correlated to AngleXF. Variation in XFI was noted in some cases originally presenting with same FBCI values. The XFI attempts to quantify the curve correcting ability as contributed by "X-Factors" in the treatment of thoracic AIS. This index may be a valued added parameter to accompany the FBCI for comparing curve correction ability among different series of patients, instrumentation, and surgeons. It is recommended that the XFI should be used to document curve correction, compare between different techniques, and used to improve curve correction for the patient. © 2010 Springer-Verlag.

Muheremu A.,Beijing Ji Shui Tan Hospital | Niu X.,Beijing Ji Shui Tan Hospital
World Journal of Surgical Oncology | Year: 2014

Giant cell tumor of bone (GCTB) accounts for 5% of primary skeletal tumors. Although it is considered to be a benign lesion, there are still incidences of pulmonary metastasis. Pulmonary metastasis of GCTB may be affected by tumor grading and localization as well as the age, gender and overall health status of the patient. Patients with local recurrence are more likely to develop pulmonary metastasis of GCTB. High expression of some genes, cytokines and chemokines may also be closely related to the metastatic potential and prognosis of GCTB. The treatment of the primary GCTB is key to the final outcome of the disease, as intralesional curettage has a significantly higher local recurrence and pulmonary metastasis rate than wide resection. However, even patients with pulmonary metastasis seem to have a good prognosis after timely and appropriate surgical resection. It is hoped that with the development of novel surgical methods and drugs, pulmonary metastasis of GCTB can be prevented and treated more effectively. © 2014 Muheremu and Niu; licensee BioMed Central Ltd.

Xu H.,Beijing Ji Shui Tan Hospital | Niu X.,Beijing Ji Shui Tan Hospital
Chinese Journal of Oncology | Year: 2014

Objective: The aim of the present study was to investigate the outcome of surgical management in patients with giant cell tumor (GCT) of extremity long hone and the risk factors for recurrence. Methods: Clinicopathological data of 145 patients with giant cell tumor of long bone treated in our hospital from 2002 to 2008 were retrospectively reviewed. There were 79 male and 66 female patients. The mean age at first diagnosis was 29 (11-66) years. There were 45 GCTs localized in the distal femur, followed by 36 in the proximal tibia, 22 in the proximal femur, 19 in the distal radius, 8 in the proximal fibula, 8 in the proximal humerus, 4 in the distal tibia and one in the distal fibula, distal humerus and proximal radius, for each. Surgical treatment included extensive curettage in 81 cases and resection in 64 cases. The possible risk factors for recurrence included age, gender, tumor location, Campanacci grading, pathologic fracture and types of surgery. The patients were followed up with a mean duration of 50 months ranging from 36 to 104 months. The correlation of age, gender, tumor location, Campanacci grading, pathologic fracture and types of surgery with the risk for recurrence was analyzed. Results: The overall local recurrence rate was 4. 8% (7/145) and the mean duration for recurrence was 20 months ranging from 4 to 52 months. The local recurrence rate was 7.4% (6/81) in the extensive curettage group and 1.6% (1/64) in the resection group (P = 0. 134). The difference was not statistically significant. Age, gender, tumor location, Campanacci grading, pathologic fracture and types of surgery were not risk factors for recurrence. Conclusions: The results of the present study suggest that clinical and imaging features and types of surgery are not affecting factors for recurrence of giant cell tumor of long bone. Extensive curettage provides similar favorable local control of the tumor as resection. We would recommend extensive curettage while resection should be done following indications.

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