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1.
Introduction Intra-articular distal radius fractures with volar and dorsal comminution present a special challenge to the hand surgeon. Methods Ten patients formed the study cohort. All plates were low profile and stainless steel. Radiographic parameters, range of motion, and strength compared to the uninjured side were recorded. Functional outcome was evaluated by Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire and Gartland and Werley scoring system. Results Median age at surgery was 58 years (range, 24 to 86). Mean follow-up was 17 months (range, 12 to 28). According to the AO classification system, there were three type C2 and seven type C3 fractures. Median preoperative dorsal angulation was 24 deg; median postoperative dorsal angulation was 3 deg. Eighty percent (8) of the fractures also had an intra-articular step-off or gap, all of which were corrected to neutral by the procedure. Compared with the contralateral side, mean extension and flexion were 73 and 75%, respectively, pronation and supination were 95 and 88%, respectively, and grip strength and thumb pinch were 72 and 87%, respectively. Mean postoperative DASH score was 16 points, and 70% (7) of the patients had Gartland and Werley scores of good or excellent. None of the patients needed to have their plates removed, and no extensor tendon rupture was reported. Conclusions The “sandwich” plating technique is an effective method of regaining near-anatomic reconstruction of intra-articular, volarly and dorsally comminuted distal radius fractures. Results from this study demonstrate that patients can expect to regain about 80% of their range of motion and strength. Moreover, 70% of the patients will have good to excellent functional outcomes. This is the first study to examine range of motion and functional outcome of low-profile “sandwich” plating without plate removal.  相似文献
2.
OBJECTIVE: The authors sought to validate the ISGPF classification scheme in a large cohort of patients following pancreaticoduodenectomy (PD) in a pancreaticobiliary surgical specialty unit. SUMMARY BACKGROUND DATA: Definitions of postoperative pancreatic fistula vary widely, precluding accurate comparisons of surgical techniques and experiences. The ISGPF has proposed a classification scheme for pancreatic fistula based on clinical parameters; yet it has not been rigorously tested or validated. METHODS:: Between October 2001 and 2005, 176 consecutive patients underwent PD with a single drain placed. Pancreatic fistula was defined by ISGPF criteria. Cases were divided into four categories: no fistula; biochemical fistula without clinical sequelae (grade A), fistula requiring any therapeutic intervention (grade B), and fistula with severe clinical sequelae (grade C). Clinical and economic outcomes were analyzed across all grades. RESULTS: More than two thirds of all patients had no evidence of fistula. Grade A fistulas occurred 15% of the time, grade B 12%, and grade C 3%. All measurable outcomes were equivalent between the no fistula and grade A classes. Conversely, costs, duration of stay, ICU duration, and disposition acuity progressively increased from grade A to C. Resource utilization similarly escalated by grade. CONCLUSIONS: Biochemical evidence of pancreatic fistula alone has no clinical consequence and does not result in increased resource utilization. Increasing fistula grades have negative clinical and economic impacts on patients and their healthcare resources. These findings validate the ISGPF classification scheme for pancreatic fistula.  相似文献
3.
The rates of fracture at sites with different relative amounts of cortical and trabecular bone (hip, spine, distal radius) have been used to make inferences about the pathomechanics of bone loss and the existence of type I and type II osteoporosis. However, fracture risk is directly related to the ratio of tissue stress to tissue strength, which in turn is dependent not only on tissue composition but also tissue geometry and the direction and magnitude of loading. These three elements determine how the load is distributed within the tissue. As a result, assumptions on the relative structural importance of cortical and trabecular bone, and how these tissues are affected by bone loss, can be inaccurate if based on regional tissue composition and bone density alone. To investigate the structural significance of cortical and trabecular bone in the proximal femur, and how it is affected by bone loss, we determined the stress distributions in a normal and osteoporotic femur resulting from loadings representing: (1) gait; and (2) a fall to the side with impact onto the greater trochanter. A three-dimensional finite element model was generated based on a representative femur selected from a large database of femoral geometries. Stresses were analyzed throughout the femoral neck and intertrochanteric regions. We found that the percentage of total load supported by cortical and trabecular bone was approximately constant for all load cases but differed depending on location. Cortical bone carried 30% of the load at the subcapital region, 50% at the mid-neck, 96% at the base of the neck and 80% at the intertrochanteric region. These values differ from the widely held assumption that cortical bone carries 75% of the load in the femoral neck and 50% of the load at the intertrochanteric region. During gait, the principal stresses were concentrated within the primary compressive system of trabeculae and in the cortical bone of the intertrochanteric region. In contrast, during a fall, the trabecular stresses were concentrated within the primary tensile system of trabeculae with a peak magnitude 4.3 times that present during gait. While the distribution of stress for the osteoporotic femur was similar to the normal, the magnitude of peak stress was increased by between 33% and 45%. These data call into question several assumptions which serve as the basis for theories on the pathomechanics of osteoporosis. In addition, we expect that the insight provided by this analysis will result in the improved development and interpretation of non-invasive techniques for the quantification of in vivo hip fracture risk.  相似文献
4.
Evaluation of an ultrasonic blood volume monitor   总被引:6,自引:6,他引:2  
Background. Hypotension complicates approximately 30% of all dialysis treatments. Although the genesis of hypotension is multifactorial, hypovolaemia is thought to play a major role as a direct result of decreased blood volume, particularly during ultrafiltration. The described blood volume monitor enables blood volume to be measured continuously by a non-invasive technique. Methods. The blood volume monitor is based on the principle that the total protein concentration, the sum of haemoglobin and plasma proteins in the vascular space, changes during ultrafiltration. Changes of total protein concentration are determined from the velocity of sound waves in blood, measured using a cuvette in the extracorporeal circuit designed for this purpose. The precision of the blood volume monitor was evaluated in 180 dialysis treatments in 49 patients. The relative blood volume obtained by the monitor was compared with a standard reference method involving calculation of relative blood volume from serial measurements of haemoglobin. Results. A very good agreement between the two methods was achieved (SD = 1.70%, r >0.96). The results showed no sensitivity to changes in serum sodium concentration (range 130-145 mmol). The 'noise' introduced in the blood volume signal was low (⩽0.2%, sampling rate 10 s) allowing subtle blood volume changes to be detected with high resolution. In addition the device enabled the measurement of haematocrit (Hct) and haemoglobin (Hb) to be made since this is the largest blood component determining total protein concentration. A comparison with the centrifuge method revealed an accuracy of ± 2.9Hct-%, and a comparison with the photometer an accuracy of ±0.8g Hb/dl. Conclusion. In summary the blood volume monitor allows precise and reliable measurement of relative blood volume. It provides the instrumentation essential for feedback control of relative blood volume during dialysis.  相似文献
5.
Background Measuring health-related quality of life (QoL) after surgery is essential for decision making by patients, surgeons, and payers. The aim of this consensus conference was twofold. First, it was to determine for which diseases endoscopic surgery results in better postoperative QoL than open surgery. Second, it was to recommend QoL instruments for clinical research.Methods An expert panel selected 12 conditions in which QoL and endoscopic surgery are important. For each condition, studies comparing endoscopic and open surgery in terms of QoL were identified. The expert panel reached consensus on the relative benefits of endoscopic surgery and recommended generic and disease-specific QoL instruments for use in clinical research.Results Randomized trials indicate that QoL improves earlier after endoscopic than open surgery for gastroesophageal reflux disease (GERD), cholecystolithiasis, colorectal cancer, inguinal hernia, obesity (gastric bypass), and uterine disorders that require hysterectomy. For spleen, prostate, malignant kidney, benign colorectal, and benign non-GERD esophageal diseases, evidence from nonrandomized trials supports the use of laparoscopic surgery. However, many studies failed to collect long-term results, used nonvalidated questionnaires, or measured QoL components only incompletely. The following QoL instruments can be recommended: for benign esophageal and gallbladder disease, the GIQLI or the QOLRAD together with SF-36 or the PGWB; for obesity surgery, the IWQOL-Lite with the SF-36; for colorectal cancer, the FACT-C or the EORTC QLQ-C30/CR38; for inguinal and renal surgery, the VAS for pain with the SF-36 (or the EORTC QLQ-C30 in case of malignancy); and after hysterectomy, the SF-36 together with an evaluation of urinary and sexual function.Conclusions Laparoscopic surgery provides better postoperative QoL in many clinical situations. Researchers would improve the quality of future studies by using validated QoL instruments such as those recommended here.Presented at the 11th International Congress of the European Association for Endoscopic Surgery (E.A.E.S.), Glasgow, Scotland, United Kingdom, June 2003(D. Korolija, S. Sauerland, E. Neugebauer) Conference organizers on behalf of the Scientific Committee of the European Association for Endoscopic Surgery (E.A.E.S.), c/o E.A.E.S. Office, P.O. Box 335, 5500 AH Veldhoven, The Netherlands  相似文献
6.
Since the identification of the osteogenic protein-1 (OP-1) gene, also called bone morphogenetic protein-7 (BMP-7), almost 20 years ago, OP-1 has become one of the most characteristic members of the BMP family. The biological activity of recombinant human OP-1 has been defined using a variety of animal models. These studies have demonstrated that local implantation of OP-1 in combination with a collagen matrix results in the repair of critical size defects in long bones and in craniofacial bones and the formation of bony fusion masses in spinal fusions. Clinical trials investigating long bone applications have provided supportive evidence for the use of OP-1 in the treatment of open tibial fractures, distal tibial fractures, tibial nonunions, scaphoid nonunions and atrophic long bone nonunions. Clinical studies investigating spinal fusion applications have provided supportive evidence for the use of OP-1 in posterolateral lumbar models and compromised patients as an adjunct or as a replacement for autograft. Both long bone repair and spinal fusion studies have demonstrated the efficacy and safety of OP-1 by clinical outcomes and radiographic measures. Future clinical investigations will be needed to better define variables, such as dose, scaffold and route of administration. Clearly the use of BMPs in orthopaedics is still in its formative stage, but the data suggest an exciting and promising future for the development of new therapeutic applications.  相似文献
7.
A pre-existing fracture is a strong predictor of additional osteoporotic fractures. Consequently, current guidelines emphasize the need for treating patients with existing osteoporotic fractures. The present study aimed to assess the implementation of osteoporosis guidelines in routine practice. To this end, we reviewed the hospital charts of women and men aged 50 years and older with new fractures due to low or moderate impact treated in the emergency room, orthopedic surgery and rehabilitation departments. Notation of osteoporosis as a contributing cause for the fracture, performance of screening laboratory tests for possible secondary causes and treatment recommendations were abstracted from the record. In addition, we utilized the centralized pharmacy and laboratory computerized databases of the largest health maintenance organization in the area to follow dispensation of osteoporosis drugs and performance of screening laboratory tests in the community following fracture incidents. During the corresponding periods of January and February 1998 and 1999, 183 patients aged 50 years and older with low-impact fractures were treated in the emergency room only and 113 were hospitalized. Osteoporosis was rarely mentioned in the medical documentation. During the 6 month period after the fracture incident at least 70% of the emergency room patients and 62% of the hospitalized patients received no osteoporosis drugs. However, an encouraging significant trend toward increasing use of osteoporosis drugs, both prior to and after a fracture incident, was noted between the two survey periods among the emergency room fracture patients, but not among the hospitalized patients. Calcium supplements were the most commonly used osteoporosis drug. Bisphosphonates, hormone replacement therapy, raloxifene and calcitonin were rarely prescribed. Men were less likely than women to receive treatment for osteoporosis. Systematic laboratory evaluations for secondary causes of osteoporosis were not performed. We conclude that despite extensive attempts at increasing awareness among health professionals and the public at large, osteoporosis is still rarely singled out as a problem in patients with newly diagnosed low-impact fractures, and the majority of them are not managed according to guidelines. Further studies should address specific problems in physicians’ and patients’ attitude that may account for the present situation. Received: May 2000 / Accepted: January 2001  相似文献
8.
Structural alterations of prosthetic meshes in humans   总被引:5,自引:5,他引:0  
The use of prosthetic mesh in abdominal wall hernia surgery is a well-accepted practice. What is not settled, however, is the type of prosthesis that best suits the purpose. The narrow choice today means a prosthesis of polyester or polypropylene. These are available in many designs, configuration of weave, thickness of weave and strand, and size of pore. There has been a pervasive feeling that these materials "shrink". To what extent they do has not been accurately defined. This study was designed to measure such "shrinkage". Interestingly, our measurements revealed that prosthetic meshes could "expand" as well as "shrink". The extent to which they do varies between –40% and 58.5%. Whereas it was felt that fibrocyte activity and its eventual scar formation accounted for the "shrinkage" of the mesh, we have discovered that structural alterations in the size of the mesh pores can be affected by distilled water, saline, blood, formalin, bleach, as well as in vivo implantation. Prosthetic meshes are, therefore, not the inert materials they are claimed to be and can expand as well as shrink. We have, unfortunately, not been able to correlate the degree or direction of change to any known parameter. Electronic Publication  相似文献
9.
Background Completion lymph node dissection (CLND) is considered the standard of care in melanoma patients found to have sentinel lymph node (SLN) metastasis. However, the therapeutic utility of CLND is not known. The natural history of patients with positive SLNs who do not undergo CLND is undefined. This multi-institutional study was undertaken to characterize patterns of failure and survival rates in these patients and to compare results with those of positive-SLN patients who underwent CLND. Methods Surgeons from 16 centers contributed data on 134 positive-SLN patients who did not undergo CLND. SLN biopsy was performed by using each institution’s established protocols. Patients were followed up for recurrence and survival. Results In this study population, the median age was 59 years, and 62% were male. The median tumor thickness was 2.6 mm, 77% of tumors had invasion to Clark level IV/V, and 33% of lesions were ulcerated. The primary melanoma was located on the extremities, trunk, and head/neck in 45%, 43%, and 12%, respectively. The median follow-up was 20 months. The median time to recurrence was 11 months. Nodal recurrence was a component of the first site of recurrence in 20 patients (15%). Nodal recurrence–free survival was statistically insignificantly worse than that seen in a contemporary cohort of patients who underwent CLND. Disease-specific survival for positive-SLN patients who did not undergo CLND was 80% at 36 months, which was not significantly different from that of patients who underwent CLND. Conclusions This study underscores the importance of ongoing prospective randomized trials in determining the therapeutic value of CLND after positive SLN biopsy in melanoma patients. Presented at the 58th Annual Cancer Symposium of the Society of Surgical Oncology, Atlanta, Georgia, March 3–6, 2005.  相似文献
10.
OBJECTIVE: This report documents that the gastric bypass operation provides long-term control for obesity and diabetes. SUMMARY BACKGROUND DATA: Obesity and diabetes, both notoriously resistant to medical therapy, continue to be two of our most common and serious diseases. METHODS: Over the last 14 years, 608 morbidly obese patients underwent gastric bypass, an operation that restricts caloric intake by (1) reducing the functional stomach to approximately 30 mL, (2) delaying gastric emptying with a c. 0.8 to 1.0 cm gastric outlet, and (3) excluding foregut with a 40 to 60 cm Roux-en-Y gastrojejunostomy. Even though many of the patients were seriously ill, the operation was performed with a perioperative mortality and complication rate of 1.5% and 8.5%, respectively. Seventeen of the 608 patients (< 3%) were lost to follow-up. RESULTS: Gastric bypass provides durable weight control. Weights fell from a preoperative mean of 304.4 lb (range, 198 to 615 lb) to 192.2 lb (range, 104 to 466) by 1 year and were maintained at 205.4 lb (range, 107 to 512 lb) at 5 years, 206.5 lb (130 to 388 lb) at 10 years, and 204.7 lb (158 to 270 lb) at 14 years. The operation provides long-term control of non-insulin-dependent diabetes mellitus (NIDDM). In those patients with adequate follow-up, 121 of 146 patients (82.9%) with NIDDM and 150 of 152 patients (98.7%) with glucose impairment maintained normal levels of plasma glucose, glycosylated hemoglobin, and insulin. These antidiabetic effects appear to be due primarily to a reduction in caloric intake, suggesting that insulin resistance is a secondary protective effect rather than the initial lesion. In addition to the control of weight and NIDDM, gastric bypass also corrected or alleviated a number of other comorbidities of obesity, including hypertension, sleep apnea, cardiopulmonary failure, arthritis, and infertility. Gastric bypass is now established as an effective and safe therapy for morbid obesity and its associated morbidities. No other therapy has produced such durable and complete control of diabetes mellitus.  相似文献
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