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Background: The Bisurface knee prosthesis was designed in 1989 to improve knee flexion without affecting the durability of the prosthesis. The prosthesis has a unique ball-and-socket joint in the midposterior portion of the femoral and tibial components, which functions as a posterior stabilizing cam mechanism and causes femoral rollback. The femoral component was made of alumina ceramic. The purpose of this study was to review the clinical results of the first 223 arthroplasties performed with this prosthesis in order to assess whether this new implant had achieved its design objectives.Methods: From December 1989 to May 1994, all patients who were scheduled for primary total knee arthroplasty were enrolled in a prospective study of the Bisurface knee. The patients were evaluated clinically according to The Hospital for Special Surgery knee-rating system and with a self-administered questionnaire, and they were evaluated radiographically according to the system of the Knee Society. Kaplan-Meier survivorship analysis was performed with revision of the knee or recommendation for revision as the end point.Results: One hundred and sixty-six patients treated with a total of 223 consecutive primary total knee arthroplasties were enrolled in the study, and 182 knees were followed for 3.9 to 9.0 years (mean, 5.8 years). Preoperatively, the mean Hospital for Special Surgery knee score was 44.5 points. At the time of latest follow-up, the mean knee score was 86.3 points. The mean preoperative and postoperative ranges of flexion were 119 and 124 degrees, respectively. The patients, even those with a good preoperative range of motion, rarely lost deep flexion of the knee after the procedure. A revision operation was performed in eight knees (because of infection in five, instability in two, and breakage of the peg of the patellar component in one). Two knees had recurrent medial-lateral subluxations of the femorotibial articulation, which were treated nonoperatively. No prosthesis had loosened aseptically and no alumina ceramic femoral component had broken by the time of latest follow-up. The rate of survival of the implant was 94 percent (95 percent confidence interval, 90 to 98 percent) at six years. According to the patient questionnaires, 20 percent of the knees sometimes felt loose in daily living activities, which prompted us to improve the intrinsic stability of the prosthesis by improving the congruity of the ball-and-socket joint.Conclusions: Total knee arthroplasty with the Bisurface prosthesis resulted in an excellent range of motion and a high level of satisfaction with the operation; the durability of the prosthesis is promising. [ABSTRACT FROM AUTHOR]

Early-life stress has long-lasting effects on neuroendocrine and behaviour in adulthood. Maternal separation ( MS) is used as a model of early-life stress and daily repeated MS ( RMS) for 3 h during the first two postnatal weeks is widely used in rodent studies. However, it is not fully understood whether early-life animals desensitise/habituate to repeated stress. In the present study, we investigated the effects of daily RMS for 3 h and acute/single time MS ( SMS) for 3 h on the plasma corticosterone level and c- Fos expression in the brain in mice at different postnatal ages. Mice were subjected to: (i) RMS from postnatal day ( PND) 1 to 14 ( RMS14); (ii) RMS from PND14 to 21 ( RMS21); (iii) SMS on PND14 ( SMS14); and (iv) SMS on PND21 ( SMS21). Plasma corticosterone and c- Fos expression were examined on the final day in each experiment. The basal corticosterone levels in RMS14 and RMS21 were equal to those in respective age-matched controls. After the final separation, the levels were significantly increased and were comparable with those after SMS14 and SMS21, respectively. Histological analysis indicated that c- Fos expression significantly increased in many brain regions, including the paraventricular nucleus, prefrontal cortex, hippocampus, and basolateral and medial amygdale in both SMS14 and SMS21 mice. However, c- Fos expression in RMS14 mice significantly increased in many regions, whereas such increases were hardly seen in RMS21 mice. These results indicate that repeated early-life stress neither increases basal corticosterone, nor decreases the magnitude of the corticosterone response during the first three postnatal weeks, although desensitisation of c- Fos expression induced by repeated stress is changed during postnatal development. [ABSTRACT FROM AUTHOR]

BACKGROUND AND PURPOSE Chondrocyte apoptosis contributes to disruption of cartilage integrity in osteoarthritis. Recent evidence suggested that the volume-sensitive organic osmolyte/anion channel [volume-sensitive (outwardly rectifying) Cl(-) current (I(Cl,vol) )] plays a functional role in the development of cell shrinkage associated with apoptosis (apoptotic volume decrease) in several cell types. In this study, we investigated the cellular effects of 17β-oestradiol on doxorubicin-induced apoptotic responses in rabbit articular chondrocytes. EXPERIMENTAL APPROACH Whole-cell membrane currents and cross-sectional area were measured from chondrocytes using a patch-clamp method and microscopic cell imaging, respectively. Caspase-3/7 activity was assayed as an index of apoptosis. KEY RESULTS Addition of doxorubicin (1 µM) to isosmotic bath solution rapidly activated the Cl(-) current with properties similar to those of I(Cl,vol) in chondrocytes. Doxorubicin also gradually decreased the cross-sectional area of chondrocytes, followed by enhanced caspase-3/7 activity; both of these responses were totally abolished by the I(Cl,vol) blocker DCPIB (20 µM). Pretreatment of chondrocytes with 17β-oestradiol (1 nM) for short (approximately 10 min) and long (24 h) periods almost completely prevented the doxorubicin-induced activation of I(Cl,vol) and subsequent elevation of caspase-3/7 activity. These effects of 17β-oestradiol were significantly attenuated by the oestrogen receptor blocker ICI 182780 (10 µM), as well as the phosphatidyl inositol-3-kinase (PI3K) inhibitors wortmannin (100 nM) and LY294002 (20 µM). Testosterone (10 nM) had no effect on the doxorubicin-induced Cl(-) current. CONCLUSIONS AND IMPLICATIONS 17β-Oestradiol prevents the doxorubicin-induced cell shrinkage mediated through activation of I(Cl,vol) and subsequent induction of apoptosis signals, through a membrane receptor-dependent PI3K pathway in rabbit articular chondrocytes. [ABSTRACT FROM AUTHOR]

This study investigated the relation between bone tunnel enlargement after posterior cruciate ligament (PCL)reconstruction and clinical results. Fourteen patients were retrospectively reviewed for tunnel measurements. All procedures employed multiple stands of hamstring tendons. Antero-posterior and lateral plain X-rays were obtained in each patient immediately after surgery and at a mean of 14 months postoperatively. We measured the diameter, the position and the angle of the bone tunnels. We defined bone tunnel enlargement greater than 3 mm as significant. Femoral bone tunnel enlargement antero-posteriorly was observed in 29% and laterally in 29%. Tibial bone tunnel enlargement antero-posteriorly was 50% and laterally in 14%. The total rate of bone tunnel enlargement was 64%. In patients with tibial bone tunnel enlargement antero-posteriorly and laterally, there was significant difference in the posterior laxity measured by a Telos SE arthrometer. In conclusion, tibial bone tunnel enlargement is associated with posterior instability after PCL reconstruction. [ABSTRACT FROM AUTHOR]

STUDY DESIGN::A case report. SETTING::Department of Orthopaedic Surgery, Shiga University of Medical Science, Japan. PATIENT::A 13-year-old woman presented progressive weakness in the lower extremities, with predominance on the right. Magnetic resonance (MR) imaging revealed a huge syrinx. The patient also showed scoliosis, cleft palate, hearing impairment, excessive sweating, hairiness, dural ectasia, and malformation of the skull. METHOD AND OBJECTIVES::We treated a very rare case of Arnold-Chiari syndrome, which presented with flaccid paralysis. Methods of differential diagnosis and suitable treatment are discussed. RESULTS AND CONCLUSION::Both the syrinx and muscle strength were quickly improved following placement of a syringo-peritoneal (S-P) shunt, after which the patient recovered the ability to walk. However, transient hypesthesia in the right hand occurred after the operation. The syrinx around the conus was thought to play a crucial role in the etiology of the patient case, which showed unique symptoms.Spinal Cord (2004) 42, 541-544. doi:10.1038/sj.sc.3101607 Published online 27 April 2004 [ABSTRACT FROM AUTHOR]

Background: Recent studies have shown that adipose tissue is an endocrine organ that releases various cytokines.Objective: To investigate the production of growth factors and proinflammatory cytokines in infrapatellar fat pad specimens.Methods: Infrapatellar fat pad tissues were obtained from patients during knee surgery. Protein levels of basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), tumour necrosis factor (TNF)alpha, and interleukin (IL)6 in homogenised tissues were measured by an enzyme immunoassay. Gene expressions for those cytokines were examined by reverse transcription-polymerase chain reaction (RT-PCR). Localisation of bFGF and VEGF was evaluated by immunohistochemistry and in situ hybridisation.Results: Infrapatellar fat pads were found to contain various protein levels of bFGF, VEGF, TNF alpha, and IL6. Further, gene expressions for these cytokines were detected by RT-PCR. Immunohistochemistry and in situ hybridisation showed that the expressions of both bFGF and VEGF were localised in immature adipocytes, interstitial undifferentiated mesenchymal cells, and vascular endothelial cells.Conclusion: The production of bFGF, VEGF, TNF alpha, and IL6 in the infrapatellar fat pad was demonstrated. Although synovial cells and articular chondrocytes are thought to be primary sources of cytokines found in knee synovial fluids, the results suggest that they may also originate from this fat pad. [ABSTRACT FROM AUTHOR]

Investigates the effects of serotonin (5-HT) agonists on in vitro models of spinal cord compressive injury. Overview of evoked potentials in injured rat spinal cords during perfusion with 5-HT agonists; Activation of conducting action potentials; Damage of the myelin sheath by spinal cord injury.

We report on a series of six cases of posteromedial impingement lesion of the ankle operated on during a 3-year period with excellent or good results and a return of the patients to preinjury levels of activity. This lesion occurs, on occasion, after a severe ankle-inversion injury in which the deep posterior fibers of the medial deltoid ligament become crushed between the medial wall of the talus and the medial malleolus. Initially, posteromedial symptoms do not predominate, compared with the symptoms of the lateral ligament disruption, and they usually resolve without specific treatment. Occasionally, however, thick, disorganized fibrotic scar tissue persists and impinges between the medial wall of the talus and the posterior margin of the medial malleolus. Clinically, the patient has persistent medial to posteromedial activityrelated ankle pain after a severe inversion injury, despite a sound ankle rehabilitation program. There is deep soft tissue induration immediately behind the medial malleolus with localized tenderness and reproduction of symptomatic pain on provocative testing by palpating this site while moving the ankle into plantar flexion and inversion. The posteromedial impingement lesion has a distinct pathologic picture and can coexist with other ankle lesions that cause pain after lateral ligament injury. [ABSTRACT FROM AUTHOR]

Objective: To investigate the septum-like structures in predominantly lipomatous tumors, by correlating fat-suppressed MR images with histopathologic findings.Design and Patients: The MR findings of three cases of well-differentiated liposarcoma (atypical lipoma), one case of lipoma-like component of dedifferentiated liposarcoma, and nine cases of lipoma were analyzed. T1-, T2-, and fat-suppressed T1-weighted images after Gd-DTPA administration were obtained. Surgical specimens from five patients (four with liposarcoma and one with lipoma) were also scanned with a MR unit, and compared with the pathologic findings.Results and Conclusions: Enhancement features of lipoma and liposarcoma were well visualized on fat-suppressed T1-weighted images after Gd-DTPA administration. The septum-like structures of liposarcoma are thick and enhanced considerably, while septa of lipoma are thin and enhanced only slightly. Pathologically, the septum-like structures of liposarcoma contained muscle fibers and the septa of lipoma represented fibrous capsule. Identification of well-enhanced septa in a predominantly lipomatous tumor helps to differentiate malignant tumors from lipomas. As the septum-like structures of liposarcoma contain a skeletal muscle component the tumor might need more extensive surgical procedures including resection of adjacent muscles. [ABSTRACT FROM AUTHOR]

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We report a case of congenital unilateral upper limb muscular hypertrophy which presented with loss of extensor tendon excursion of a single digit in late adolescence. The reason for the problem arising is not clear and is not clearly explained by the underlying congenital pathology. [Copyright &y& Elsevier]

STUDY DESIGN:: Case report. OBJECTIVES:: To report a case of a thoracic intramedullary spinal cord metastasis of ovarian tumor in a 59-year-old woman. SETTING:: Shiga, Japan. CASE REPORT:: A case of a thoracic intramedullary spinal cord metastasis of ovarian tumor in a 59-year-old woman is reported. She received abdominal ovariectomy for the ovarian adenocarcinoma 4 years before she suffered from back pain and showed neurological symptoms. The thoracic intramedullary lesion was confirmed by preoperative magnetic resonance imaging. She showed complete paralysis before operation. The excision of the tumor was achieved through the posterior approach. Histologically, the diagnosis of metastasis of adenocarcinoma was made. CONCLUSION:: Although she did not show any postoperative neurologic recovery, her general condition was good and there was no evidence of recurrence 24 months after surgery.Spinal Cord (2004) 42, 485-487. doi:10.1038/sj.sc.3101572; Published online 6 July 2004 [ABSTRACT FROM AUTHOR]