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21.
We report a case of periprosthetic fracture of the proximal tibia after lateral unicompartmental knee arthroplasty following a trivial fall. At the time of surgery, the components were found to be loose; and there was a large uncontained tibial defect with bone loss and communition at the fracture site. The patient was treated by revision total knee arthroplasty and proximal structural tibial allograft, with a satisfactory result at 5-year follow up. Our case illustrates that a bone-conserving unicompartmental knee arthroplasty, if complicated by a periprosthetic fracture, can also present with a difficult surgical problem. Attention to preoperative planning and to availability of structural allograft for such difficult cases is recommended. 相似文献
22.
A non-randomised retrospective study to compare the results of surgical correction of scoliosis in Duchenne’s muscular dystrophy
(DMD) patients using three different instrumentation systems—Sublaminar instrumentation system (Group A), a hybrid of sublaminar
and pedicle screw systems (Group B) and pedicle screw system alone (Group C). Between 1993 and 2003, 43 patients with DMD
underwent posterior spinal fusion and instrumentation. Group A (n = 19) had sublaminar instrumentation system, Group B (n = 13) had a hybrid construct and Group C (n = 11) was treated with pedicle system. The mean blood loss in Group A was 4.1 l, 3.2 l in Group B and 2.5 l in Group C. Average
operating times in Group A, B and C were 300, 274 and 234 min, respectively. Mean pre-operative, post-operative and final
Cobb angle in Group A was 50.05 ± 15.46°, 15.68 ± 11.23° and 21.57 ± 11.63°, Group B was 17.76 ± 8.50°, 3.61 ± 2.53° and 6.69 ± 4.19°
and Group C was 25.81 ± 9.94°, 5.45 ± 3.88°, 8.90 ± 5.82°, respectively. Flexibility index or the potential correction calculated
from bending radiographs were 60 ± 6.33, 70 ± 4.65 and 67 ± 6.79% for Group A, Group B and Group C respectively. The percentage
correction achieved was 72.5 ± 14.5% in Group A, 82 ± 6% in Group B and 82 ± 8% in Group C. The difference between percentage
correction achieved and the flexibility index was 12.45 ± 8.22, 12.05 ± 1.3 and 15.00 ± 1.21% in Group A, B and C, respectively
The percentage loss of correction in Cobb angles at final follow-up in Group A, B and C was 12.5 ± 3.5, 16.5 ± 1. and 12.5 ± 2.5%,
respectively. Complications seen in Group A were three cases of wound infection and two cases of implant failure; Group B
had a single case of implant failure and Group C had one patient with wound infection and one case with a partial screw pull
out. Early surgery and smaller curve corrections appears to be the current trend in the management of scoliosis in DMD. This
has been possible due to early curve detection and surgery thus having the advantage of less post-operative respiratory complications
and stay in paediatric intensive care. Also, early surgery avoids development of pelvic deformity and extension of instrumentation
to the pelvis thereby reducing blood loss. This trend reflects the advent of newer and safer instrumentation systems, advanced
techniques in anaesthesia and cord monitoring. Sublaminar instrumentation system group had increased operating times and blood
loss compared to both the hybrid and pedicle screw instrumentation systems due to increased bleeding from epidural vessels
and pelvic instrumentation. Overall, the three instrumentation constructs appear to provide and maintain an optimal degree
of correction at medium to long term follow up but the advantages of lesser blood loss and surgical time without the need
for pelvic fixation seem to swing the verdict in favour of the pedicle screw system. 相似文献
23.
Periprosthetic fracture following total knee arthroplasty is a potentially serious complication. This injury can involve the distal femur, proximal tibia or the patella. This review article analyzes the prevalence, risk factors, classification and treatment options for periprosthetic fractures of the femur. 相似文献
24.
Melatonin prevents dexamethasone‐induced testicular oxidative stress and germ cell apoptosis in golden hamster,Mesocricetus auratus 下载免费PDF全文
This study investigated the protective effect of melatonin on dexamethasone (Dex), an extensively used anti‐inflammatory and immunosuppressive synthetic glucocorticoid, induced testicular oxidative stress and germ cell apoptosis in golden hamster. Hamsters were randomly divided into four groups (n = 7): group I – control; group II – melatonin treated (10 mg kg?1 day?1); group III – Dex treated (7 mg kg?1 day?1) and group IV – combination of Dex and melatonin. All the injections were administered intraperitoneally for seven consecutive days. The histopathological changes, specific biochemical markers, including antioxidative enzymes, plasma melatonin level and the markers for germ cell apoptosis were evaluated. Dex administration decreased antioxidant enzyme activities (SOD, CAT, GSH‐PX), plasma melatonin level and melatonin receptor (MT1) expression with a concomitant increase in lipid peroxidation (TBARS) and altered testicular histopathology which might culminate into increased germ cell apoptosis as evident from increased Bax/Bcl‐2 ratio and caspase‐3 expression. However, melatonin pre‐treatment enhanced enzyme activities for SOD, CAT, GSH‐PX with a simultaneous decrease in Bax/Bcl‐2 ratio and caspase‐3 expression. Our findings clearly suggest that melatonin improved defence against Dex‐induced testicular oxidative stress and prevented germ cell apoptosis, suggesting a novel combination therapeutic approach for management of male reproductive health. 相似文献
25.
26.
BACKGROUND CONTEXT: Previous studies have analyzed the outcome following posterior correction and combined anterior-posterior correction for Scheuermann's kyphosis. Traditionally interbody fusion has been obtained using morselized rib graft. Recently the use of titanium anterior cages has been suggested for interbody use. There are no long-term studies comparing these two techniques. PURPOSE: To investigate the potential value of titanium anterior interbody cages compared with morselized rib graft for anterior interbody fusion in combination with posterior instrumentation, correction, and fusion for Scheuermann's kyphosis. STUDY DESIGN: Nonrandomized comparison of two surgical techniques in matched subjects. PATIENT SAMPLE: Fifteen patients with identical preoperative radiographic and physical variables (age, gender, height, weight, body mass index) were managed with combined anterior release, interbody fusion, posterior instrumentation, correction, and fusion. Group A (n=8) had morselized rib graft inserted into each intervertebral disc space. Group B (n=7) had titanium interbody cages packed with bone graft inserted at each level. The posterior instrumentation extended from T2 to L2 in both groups. OUTCOME MEASURES: Preoperative and postoperative curve morphometry was studied on plain radiographs by two independent observers. The indices studied included Cobb angle, Ferguson's angle, Voutsinas index, sagittal vertical axis (SVA), sacral inclination (SI), and lumbar lordosis (LL). Interbody fusion was assessed at final follow-up. Each patient was reviewed at 3, 6, 12, 24, 48, and 60 months after surgery with standing radiographs. METHODS: Both surgical groups were compared in terms of radiological parameters and complications. Wilcoxon-matched pairs test and Mann-Whitney test were used. RESULTS: The average follow-up for Group A was 70 months and for Group B 66 months. For the whole group, the preoperative median Cobb angle for thoracic kyphosis was 86 degrees , the median Ferguson angle was 50 degrees , Voutsinas index was 28.7, SVA -3.5 centimeters, lumbar lordosis was 66 degrees , and the median sacral inclination angle was 40 degrees . The median postoperative Cobb angle was 42 degrees , Ferguson angle 28.4 degrees , Voutsinas index 13, SVA -4.0 centimeters, and the median sacral inclination angle was 34 degrees . There were significant differences between preoperative and postoperative measurements for all variables (p<.01), indicating that good correction was achieved. At 4-year follow-up, fusion criteria were satisfied in 12 of 15 cases (80%). Three patients had distal junctional kyphosis. There was no significant difference obtained in the final Cobb angle, Ferguson angle, and Voutsinas index when Group A (rib graft) was compared with Group B (titanium cage) Both Group A and B patients retained the postoperative correction achieved with respect to all the radiographic parameters studied. CONCLUSION: We were unable to demonstrate any significant advantage for the use of anterior titanium interbody cages over the use of morselized rib graft in the surgical management of Scheuermann's kyphosis. Given the not inconsiderable cost and the need for posterior chevron osteotomies when interbody cages are used, we have now reverted to our previous practice of using morselized rib graft at each intervertebral level. 相似文献
27.
Spectral Clustering for Unsupervised Segmentation of Lower Extremity Wound Beds Using Optical Images
Dhiraj Manohar Dhane Vishal Krishna Arun Achar Chittaranjan Bar Kunal Sanyal Chandan Chakraborty 《Journal of medical systems》2016,40(9):207
Chronic lower extremity wound is a complicated disease condition of localized injury to skin and its tissues which have plagued many elders worldwide. The ulcer assessment and management is expensive and is burden on health establishment. Currently accurate wound evaluation remains a tedious task as it rely on visual inspection. This paper propose a new method for wound-area detection, using images digitally captured by a hand-held, optical camera. The strategy proposed involves spectral approach for clustering, based on the affinity matrix. The spectral clustering (SC) involves construction of similarity matrix of Laplacian based on Ng-Jorden-Weiss algorithm. Starting with a quadratic method, wound photographs were pre-processed for color homogenization. The first-order statistics filter was then applied to extract spurious regions. The filter was selected based on the performance, evaluated on four quality metrics. Then, the spectral method was used on the filtered images for effective segmentation. The segmented regions were post-processed using morphological operators. The performance of spectral segmentation was confirmed by ground-truth pictures labeled by dermatologists. The SC results were additionally compared with the results of k-means and Fuzzy C-Means (FCM) clustering algorithms. The SC approach on a set of 105 images, effectively delineated targeted wound beds yielding a segmentation accuracy of 86.73 %, positive predictive values of 91.80 %, and a sensitivity of 89.54 %. This approach shows the robustness of tool for ulcer perimeter measurement and healing progression. The article elucidates its potential to be incorporated in patient facing medical systems targeting a rapid clinical assistance. 相似文献
28.
Transmigration of an impacted tooth through the symphyseal suture is a rare and special developmental anomaly of unknown etiology that is unique to the mandibular canine. Maxillary canine transmigration is even rarer. Transmigrated canines are particularly significant due to the aesthetic and functional importance. A maxillary lateral incisor crossing the mid-palatal suture has never been reported in the literature. The aim of this report is to present the first case of simultaneous transmigration of a lateral incisor and canine in the maxilla. The paper also reports four unusual cases of unilateral canine transmigration in the maxilla and mandible and successful eruption of one of the transmigrated mandibular canines following orthodontic traction. Etiology of transmigration and its clinical considerations are also discussed. 相似文献
29.
Diaminodiphenyl sulphone (dapsone) is a drug of choice in the treatment of leprosy. It is also useful for the treatment of many neutrophilic and other dermatoses. Dapsone hypersensitivity syndrome is a rare but well recognized serious adverse effect characterized by fever, skin rashes, generalized lymphadenopathy, hepatitis, and hepato-splenomegaly. Twenty-six patients with dapsone hypersensitivity syndrome were studied for clinical profile, outcome, and prognosis. The male:female ratio was 2.2:1, and the mean age was 33.19 years (range 13 to 64 years). The interval between start of dapsone therapy and appearance of symptoms varied from 2-7 weeks (mean 29.82 days). Twenty-four patients received dapsone as a part of multi-drug therapy for leprosy; the other two patients received dapsone for lichen planus and acne vulgaris. Exfoliative dermatitis was the most common cutaneous manifestation followed by erythematous maculo-papular eruption and Stevens-Johnson syndrome-like lesion. The other common systemic manifestations were: fever (26 cases), itching (22 cases), lymphadenopathy (21 cases), jaundice (21 cases), pallor (20 cases), hepatomegaly (19 cases), and pedal edema (14 cases). Investigation profile revealed elevated levels of serum liver enzymes in 100% of patients, elevated erythrocyte sedimentation rate in 92.3%, raised bilirubin in 84.6%, leucocytosis in 69.23%, low hemoglobin (<9 gm/dl) in 46.15% and hypoproteinemia in 42.3%. Eosinophilia, hemolytic anemia, and reticulocytosis count were found in 4 patients each. All the patients had favorable outcomes except three who died due to hepatic failure. Medical personnel must be aware of this potentially fatal syndrome, because it can cause considerable morbidity and mortality. 相似文献
30.
Darwish T Brahma A O'Donnell C Efron N 《Journal of cataract and refractive surgery》2007,33(9):1515-1521
PURPOSE: To evaluate recovery of the corneal subbasal nerve plexus and corneal sensitivity after myopic laser in situ keratomileusis (LASIK) and laser-assisted subepithelial keratectomy (LASEK). SETTING: Manchester Centre for Vision, Royal Eye Hospital, Manchester, United Kingdom. METHODS: Thirty LASEK patients and 20 LASIK patients had slit-scanning confocal microscopy and noncontact corneal esthesiometry preoperatively and 1, 3, and 6 months after surgery. Images of the subbasal nerve plexus were analyzed using customized software to evaluate nerve regeneration. RESULTS: Central corneal sensitivity decreased significantly 1 month after LASEK and LASIK and returned to normal levels after 3 months. Corneal subbasal nerve fiber density, nerve branch density, nerve fiber length, and nerve fiber width decreased significantly 1 month after LASIK and had not returned to the preoperative levels by 6 months. Nerve fiber tortuosity decreased significantly 1 month after LASEK and returned to the preoperative levels 3 months after surgery. There were no significant differences in nerve fiber tortuosity before and after LASIK. Neither corneal sensitivity nor nerve fiber morphology was different between the 2 groups at any postoperative visit. CONCLUSIONS: Corneal sensitivity and subbasal nerve morphology were adversely affected by LASEK and LASIK. Corneal sensitivity recovered 3 months after the procedure, but subbasal nerves were still abnormal after 6 months. Despite the different forms of surgical trauma to corneal nerves with LASIK and LASEK, there was no apparent difference in the time course of recovery of corneal structure and function. 相似文献