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61.
In order to clarify how intra-articular lesions influence the survival of a periacetabular osteotomy in patients with dysplasia of the hip, we performed an observational study of 121 patients (121 hips) who underwent a transposition osteotomy of the acetabulum combined with an arthroscopy. Their mean age was 40.2 years (13 to 64) and the mean follow-up was 9.9 years (2 to 18). Labral and cartilage degeneration tended to originate from the anterosuperior part of the acetabulum, followed by the femoral side. In all, eight hips (6.6%) had post-operative progression to Kellgren-Lawrence grade 4 changes, and these hips were associated with the following factors: moderate osteoarthritis, decreased width of the joint space, joint incongruity, and advanced intra-articular lesions (subchondral bone exposure in the cartilage and a full-thickness labral tear). Multivariate analysis indicated subchondral bone exposure on the femoral head as an independent risk factor for progression of osteoarthritis (p = 0.003). In hips with early stage osteoarthritis, femoral subchondral bone exposure was a risk factor for progression of the grade of osteoarthritis. Although the outcome of transposition osteotomy of the acetabulum was satisfactory, post-operative progression of osteoarthritis occurred at a high rate in hips with advanced intra-articular lesions, particularly in those where the degenerative process had reached the point of femoral subchondral bone exposure.  相似文献   
62.

Background

Since Sugioka transtrochanteric anterior rotational osteotomy (ARO) for osteonecrosis of the femoral head (ONFH) changes the morphology of the proximal femur, total hip arthroplasty (THA) after previous ARO is considered a technically demanding procedure. The purpose of this study was to compare the clinicoradiologic outcomes of THA after ARO with those of THA without any antecedent surgery for ONFH.

Methods

Twenty-four hips in 20 patients who underwent cementless THA after ARO (postosteotomy group) were retrospectively reviewed and compared with patients who underwent cementless THA without any antecedent surgery for ONFH during the same period (primary group). In the postosteotomy group, the mean duration from ARO to THA was 19.7 years. All patients were followed for at least 5 years (mean, 8.3 years; follow-up rate, 78.5%). A clinical assessment was performed preoperatively and at the latest follow-up using the Harris Hip Score. A radiographic examination was performed at 3 months after THA and at the latest follow-up.

Results

The Harris Hip Score at the latest follow-up in the postosteotomy group was equivalent to that in the primary group, but longer operation time and greater intraoperative blood loss were observed in the postosteotomy group. There were no significant differences in postoperative complications, including dislocation (2 hips in each group). The leg lengthening in the postosteotomy group tended to be longer. No hips showed implant malpositioning, loosening, or required any revision surgery.

Conclusion

The clinicoradiologic outcomes of THA after ARO are considered to be comparable with those of THA without any antecedent surgery for ONFH.  相似文献   
63.

Purpose

The combined anteversion (CA) technique is a method in which the cup is placed according to the stem anteversion in total hip arthroplasty (THA). We examined whether the CA technique reduced the dislocation rate, and the distribution of CA with the manual placement of the cup.

Methods

We retrospectively reviewed 634 hips in 579 patients with primary cementless THA. In 230 hips using the CA technique [CA(+)], a CA of 50 ± 10° was the aim. In the remaining 404 hips [CA(−)], the cup was first placed targeting 20° of anteversion. The post-operative CA was measured using the computed tomography (CT) images in 111 hips.

Results

One hip (0.4 %) had a dislocation in the CA(+) group, whereas ten hips (2.5 %) had a dislocation in the CA(−) group. A multivariate analysis showed that primary diagnosis, head size and CA technique significantly influenced the dislocation rate. Patients in the CA(−) group were 5.8 times more likely to have a dislocation compared to the CA(+) group. In the 111 hips with CT images, 81 hips (73.0 %) achieved the intended CA.

Conclusions

Although the manual placement of the cup resulted in 27 % of outliers from the intended CA, the CA technique significantly reduced the dislocation after primary THA.  相似文献   
64.
To investigate cytokine/chemokine changes in amyotrophic lateral sclerosis (ALS), we simultaneously measured 16 cytokine/chemokines (interleukin [IL]-1beta, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12 [p70], IL-13, IL-17, interferon-gamma, tumor necrosis factor-alpha, granulocyte colony stimulating factor [G-CSF], macrophage chemoattractant protein-1 [MCP-1], and macrophage inflammatory protein-1beta) in cerebrospinal fluid (CSF) and sera from 37 patients with sporadic ALS and 33 controls using a multiplexed fluorescent bead-based immunoassay. We also conducted immunohistochemical analyses from 8 autopsied ALS cases and 6 nonneurologic disease controls as well as cell culture analyses of relevant cytokines and their receptors. We found that concentrations of G-CSF and MCP-1 were significantly increased in ALS CSF compared with controls. In spinal cords, G-CSF was expressed in reactive astrocytes in ALS cases but not controls, whereas G-CSF receptor expression was significantly decreased in motor neurons of spinal cords from ALS cases. Biologically, G-CSF had a protective effect on the NSC34 cell line under conditions of both oxidative and nutritional stress. We suggested that G-CSF has potentially neuroprotective effects on motor neurons in ALS and that downregulation of its receptor might contribute to ALS pathogenesis. On the other hand, MCP-1 correlated with disease severity, which may aggravate motor neuron damage.  相似文献   
65.
We report the case of a 65-year-old man who had encephalitis with a high titer of voltage-gated potassium channel antibodies (VGKC-Abs). His initial symptoms included memory disturbance, confusion, and seizures. Laboratory tests revealed a low plasma sodium concentration and a strong positive result for VGKC-Abs. A diffusion-weighted magnetic resonance imaging (MRI) scan showed a high intensity lesion within the right basal ganglia, which later showed normal intensity. The patient's initial symptoms resolved without any treatment. During the first relapse, the patient experienced consciousness disturbance and an increased number of seizures than that observed initially. A diffusion weighted MRI scan showed a high intensity lesion within the right hippocampus, and a fluid attenuated inversion recovery (FLAIR) weighted MRI scan showed high intensity lesions within the right hippocampus, right thalamus, and pons. The patient's symptoms and the MRI abnormalities resolved with prednisolone therapy. During the second relapse, he again experienced consciousness disturbance and an increased number of seizures than that observed initially. Diffusion-and FLAIR weighted MRI scans showed high intensity lesions within the right thalamus. However, the array of immunosuppressive treatments used during the first relapse was not as effective during the second relapse. The serum VGKC-Ab titers before steroid therapy during the first relapse and after immunosuppressive treatment during the second relapse were 1,252 pmol/L and 22.4 pmol/L, respectively. Brain MRI revealed signal changes in the basal ganglia at the onset of disease, in the limbic area during the first relapse, and in the thalamus during the second relapse. VGKC-Ab-associated encephalopathy is usually considered a benign autoimmune disorder; however, in our case, the encephalitis gradually became intractable to various immunosuppressive treatments, and unique MRI abnormalities were observed.  相似文献   
66.
We investigated the effect of the lgG from patients with myasthenia gravis (MG) on the degradation of normal rat junctional acetylcholine receptor (AChR) labeled with 125l-α-bungarotoxin (BuTx) and calculated the degradation rate (DR). The DR for the lgG from these patients was significantly higher than that from healthy volunteers and patients with other autoimmune diseases. For MG, DR was significantly correlated with the severity of the disease but not with anti-AChR antibody titer. DR was accelerated by lgG from patients with generalized MG whose antibody titers were in the normal range and by lgG from patients with ocular MG. These results indicate that measurement of the DR of junctional AChR in normal rats is more closely correlated with the severity of the disease than is measurement of anti-AChR antibody and that the former is a sensitive and confirmatory method for evaluating MG. © 1993 John Wiley & Sons, Inc.  相似文献   
67.
Oral cenesthopathy is a somatic delusion or hallucination involving the oral area and is categorized as a delusional disorder, somatic type. The pathophysiology of this intractable condition remains obscure. In this study, we clarified the pathophysiology of oral cenesthopathy by evaluating regional brain perfusion. We performed single photon emission computed tomography (SPECT) using 99mTc-ethylcysteinate dimer in 16 subjects (cenesthopathy:control = 8:8). The SPECT images were visually assessed qualitatively, and quantitative analyses were also performed using a three-dimensional stereotactic region-of-interest template. The visual assessment revealed a right > left perfusion asymmetry in broad areas of the brain among the patients. The quantitative analysis confirmed that the regional cerebral blood flow values on the right side were significantly larger than those on the left side for most areas of the brain in the patients. A comparison of the R/(R + L) ratios in both groups confirmed the significant brain perfusion asymmetry between the two sides in the callosomarginal, precentral, and temporal regions in the patients. Qualitative evaluation of the SPECT images revealed right > left brain perfusion asymmetry in broad regions of the brain. Moreover, the quantitative analyses confirmed the perfusion asymmetry between the two sides in the frontal and temporal areas. Those may provide the key for elucidation of the pathophysiology of oral cenesthopathy.  相似文献   
68.
Purpose. This study evaluated the usefulness of performing regular finger dilation (RFD) of the anastomosis to prevent stenosis after low anterior resection (LAR). Methods. Defecatory function was assessed in 22 patients who had undergone LAR more than 6 months earlier. The patients were divided into an RFD group, comprising 15 patients who had undergone regular RFD, and a non-RFD group, comprising 7 patients who had dropped out of our follow-up with RFD. The physiological and clinical findings in relation to defecatory function were compared. Results. The type and size of the stapler and anal manometric parameters were similar. The RFD group had significantly better defecatory function in terms of bowel movement and sensation of incomplete evacuation (P < 0.01, respectively) with a significantly wider anastomotic diameter and higher evacuation rate (P < 0.01, respectively). Conclusion. These findings demonstrate that RFD is useful for preventing anastomotic stenosis and achieving favorable defecatory function after LAR. Therefore, a prospective randomized study should be scheduled. Received: February 13, 2001 / Accepted: September 11, 2001  相似文献   
69.
70.
BACKGROUND: Direct mechanical ventricular actuation (DMVA) is a non-blood contacting method of biventricular support. DMVA employs a vacuum attached, pneumatically regulated, flexible membrane to transfer both systolic and diastolic forces to the ventricular myocardium. The purpose of this study was to determine if DMVA effectively restores pump performance when applied to the severely failing heart. METHODS: Bovines (n = 10) underwent thoracotomy and were instrumented for continuous hemodynamic monitoring. Cardiac failure was induced by beta1-blockade to achieve a cardiac index of < 1.5 l/min/m2 for 1 hour. Heart rate was maintained at 100 bpm by atrioventricular sequential pacing. Synchronous DMVA support was then applied for 3 hours. RESULTS: Eight animals achieved significant reductions in cardiac index and mean arterial pressures (35%* and 43%* control, respectively; *p < 0.05). DMVA restored cardiac index to baseline and significantly increased arterial pressures (p < 0.05; DMVA versus cardiac failure). Pulmonary flow and mean pulmonary artery pressures were similar to baseline during DMVA (p = NS). Pathologic exam did not demonstrate evidence of significant device trauma. CONCLUSIONS: DMVA support can effectively restore pump performance of the acutely failing heart. Synchronization may be inherent to the stimulus of cardiac compression. These data further substantiate DMVA's potential as an adjunct to the field of circulatory support.  相似文献   
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