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101.
PURPOSE: The 2002 tumor classification for renal cell carcinoma (RCC) classifies pT2 tumors as more than 7 cm in greatest dimension, limited to the kidney. In this study we determined whether a size cutoff point exists within pT2 tumors and whether such subclassification would further improve the accuracy of the current tumor classification. MATERIALS AND METHODS: We studied 544 patients with unilateral, sporadic pT2 RCC treated with radical nephrectomy or nephron sparing surgery between 1970 and 2000. The association of tumor size with death from RCC was examined using martingale residuals from a Cox proportional hazards regression model to determine the optimal size cutoff point. RESULTS: There were 204 deaths from RCC a median of 3.8 years following nephrectomy. Univariately tumor size was significantly associated with death from RCC (risk ratio 1.08, 95% CI 1.04 to 1.13, p <0.001). A scatterplot of tumor size vs expected risk of death per patient suggested that a cutoff point between 9 and 10 cm was appropriate. When adjusted for regional lymph node involvement and distant metastases, the 10 cm cutoff point performed better than the 9 cm point (risk ratio 1.42, 95% CI 1.07 to 1.90, p = 0.017 vs 1.22, 95% 0.86 to 1.72, p = 0.268). Therefore, we propose using a 10 cm cutoff point to subclassify patients into pT2a and pT2b. CONCLUSIONS: Our data suggest that the prognostic accuracy of the 2002 pT2 tumor classification can be further improved by subclassifying patients with tumors greater than 7 and less than 10 cm into a pT2a category, and those with tumors 10 cm or greater into a pT2b category.  相似文献   
102.
103.
ObjectiveTo evaluate the rates of technical success, clinical success, and complications of fluoroscopy-guided lumbar cerebrospinal fluid drainage.ResultsThe technical and clinical success rates were 99.0% (95/96) and 89.6% (86/96), respectively. The mean hospital stay for an external lumbar drain was 4.84 days. Nine cases of minor complications and eight major complications were observed, including seven cases of meningitis, and one retained catheter requiring surgical removal.ConclusionFluoroscopy-guided external lumbar drainage is a technically reliable procedure in difficult patients with failed attempts at a bedside procedure, history of lumbar surgery, difficulties in cooperation, or obesity.  相似文献   
104.
BACKGROUND: Epidural morphine has proven analgesic efficacy in the postoperative period and is widely used. This study evaluated the efficacy of extended-release epidural morphine (EREM; DepoDur; Endo Pharmaceuticals Inc., Chadds Ford, PA; SkyePharma, Inc., San Diego, CA) in providing pain relief for 48 h after surgery. METHODS: Patients (n = 200) scheduled to undergo total hip arthroplasty were randomized to receive a single dose of 15, 20, or 25 mg EREM or placebo. After surgery and after asking for pain medication, patients had access to intravenous patient-controlled analgesia fentanyl for breakthrough pain as needed. Postoperative intravenous patient-controlled analgesia fentanyl use, time to first postoperative fentanyl use, pain intensity at rest and with activity, patient and surgeon ratings of pain control, and adverse events were recorded. RESULTS: All EREM dosages reduced the mean (+/- SD) fentanyl use versus placebo (510 +/- 708 vs. 2,091 +/- 1,803 microg; P < 0.0001) and delayed the median time to first dose of fentanyl (21.3 vs. 3.6 h; P < 0.0001). All EREM groups had significantly improved pain control at rest through 48 h postdose (area under the curve [0-48 h]) compared with placebo (P < 0.0005). More EREM-treated patients rated their pain control as good or very good compared with placebo (at 24 h: 90 vs. 65%, P < 0.0001; at 48 h: 83 vs. 67%, P < 0.05). No supplemental analgesia was needed in 25% of EREM-treated patients and 2% of placebo-treated patients at 48 h (P < 0.05). The safety profile of EREM was consistent with that of other epidurally administered opioid analgesics. CONCLUSIONS: EREM provided significant postoperative pain relief over a 48-h period after hip surgery, without the need for indwelling epidural catheters.  相似文献   
105.
Plantar forefoot pressure changes after second metatarsal neck osteotomy   总被引:3,自引:0,他引:3  
BACKGROUND: The aim of this study was to evaluate plantar pressure changes after second metatarsal neck osteotomy using the Weil technique. METHODS: Six below-knee cadaver specimens were used. Each specimen was held in a custom-built apparatus and loaded to 500 N for a period of 3 seconds. Using a computerized Musgrave pedobarograph, pressure measurements were made before and after osteotomy in both neutral and 45-degree heel rise positions. All osteotomies were made at an angle of approximately 20 degrees relative to the long axis of the metatarsal shaft. The metatarsal heads were displaced proximally by 5 mm and fixed with a single Kirschner wire. RESULTS: After osteotomy there was an average decrease in pressure beneath the second metatarsal from 70.6 to 45.1 kPa in neutral and from 813.0 to 281.4 kPa in heel rise, representing statistically significant (p < or = 0.05) decreases of 36% and 65%, respectively. There also were significant decreases beneath the third metatarsal in both neutral (39%) and heel rise (37%), and beneath the fourth metatarsal in neutral position (28%). A significant pressure increase occurred beneath the first metatarsal in neutral (23%). No significant pressure changes occurred under the fifth metatarsal in either position. CONCLUSION: Overall, our results indicated that the Weil metatarsal neck osteotomy is effective at offloading the second metatarsal head at neutral and heel rise positions.  相似文献   
106.
Hip osteoarthritis is a common cause of musculoskeletal pain in older adults and may result in decreased mobility and quality of life. Although the presentation of hip osteoarthritis varies, surgical management is required when the disease is severe, longstanding, and unresponsive to nonoperative treatments. For stakeholders to plan for the expected increased demand for surgical procedures related to hip osteoarthritis, including arthroplasty, it is important to first understand its prevalence. We conducted a systematic review by searching MEDLINE® and EMBASE to identify recent English language articles reporting on the prevalence of radiographic primary hip osteoarthritis in the general adult population; references including studies and primary studies from previous systematic reviews were also searched. This strategy yielded 23 studies reporting 39 estimates of overall prevalence ranging from 0.9% to 27% with a mean of 8.0% and a standard deviation of 7.0%. Heterogeneity was noted in study populations, eligibility criteria, age and gender distribution, type of radiographs, and method of diagnosis. Although the association between radiographic hip osteoarthritis and the need for eventual surgical management is still unclear, this study supports assertions that hip osteoarthritis is a prevalent condition whose treatment will continue to place important demands on health services.  相似文献   
107.
Background contextLow back pain (LBP) is associated with high health-care utilization and lost productivity. Numerous interventions are routinely used, although few are supported by strong evidence. Cost utility analyses (CUAs) may be helpful to inform decision makers.PurposeTo conduct a systematic review of CUAs of interventions for LBP.Study designSystematic review.MethodsA search strategy combining medical subject headings and free text related to LBP and health economic evaluations was executed in MEDLINE. Cost utility analyses combined with randomized controlled trials for LBP were included. Studies that were published before 1998, non-English, decision analyses, and duplicate reports were excluded. Search results were evaluated by two reviewers, who extracted data independently related to clinical study design, economic study design, direct cost components, utility results, cost results, and CUA results.ResultsThe search produced 319 citations, and of these 15 met eligibility criteria. Most were from the United Kingdom (n=8), published in the past 3 years (n=12), studied chronic LBP or radiculopathy (n=13), and had a follow-up >12 months (n=13). Combined, there were 33 study groups who received a mean 2.1 interventions, most commonly education (n=17), exercise therapy (n=13), spinal manipulation therapy (n=7), surgery (n=7), and usual care from a general practitioner (n=7). Mean baseline utility was 0.57, improving to 0.67 at follow-up; the mean difference in utility improvement between study groups was 0.04. Based on available data and converted to US dollars, the cost per quality-adjusted life year ranged from $304 to $579,527, with a median of $13,015.ConclusionsFew CUAs were identified for LBP, and there was heterogeneity in the interventions compared, direct cost components measured, indirect costs, other methods, and results. Reporting quality was mixed. Currently published CUAs do not provide sufficient information to assist decision makers. Future CUAs should attempt to measure all known direct cost components relevant to LBP, estimate indirect costs such as lost productivity, have a follow-up period sufficient to capture meaningful changes, and clearly report methods and results to facilitate interpretation and comparison.  相似文献   
108.
Background contextPatients with back dominant pain generally have a worse prognosis after spine surgery when compared with patients with leg dominant pain. Despite the importance of determining whether patients with lumbar spine pain have back or leg dominant pain as a predictor for success after decompression surgery, there are limited data on the reliability of methods for doing so.PurposeTo assess the test-retest reliability of a patient's ability to describe whether their lumbar spine pain is leg or back dominant using standardized questions.Study design/settingProspective, blinded, test-retest cohort study performed in an academic spinal surgery clinic.Patient sampleConsecutive patients presenting for consultation to one of three spinal surgeons for lumbar spine pain were enrolled.Outcome measuresEight questions to ascertain a patient's dominant location of pain, either back dominant or leg dominant, were identified from the literature and local experts.MethodsThese eight questions were administered in a test-retest format over two weeks. The test-retest reliability of these questions were assessed in a self-administered questionnaire format for one group of patients and by a trained interviewer in a second group.ResultsThe test-retest reliability of each question ranged from substantial (eg, interviewer-administered percent question, weighted kappa=0.77) to slight (eg, self-administered pain diagram, weighted kappa=0.09). The Percent question was the most reliable in both groups (self-administered, interviewer). All questions in the interviewer-administered group were significantly (p<.001) more reliable than the self-administered group. Depending on the question, between 0% and 32% of patients provided a completely opposite response on test-retest. There was variability in prevalence of leg dominant pain, depending on which question was asked and there was no single question that identified all patients with leg dominant pain.ConclusionA patient's ability to identify whether his or her lumbar spine pain is leg or back dominant may be unreliable and depends on which questions are asked, and also how they are asked. The Percent question is the most reliable method to determine the dominant location of pain. However, given the variability of responses and the generally poorer reliability of many specific questions, it is recommended that multiple methods be used to assess a patient's dominant location of pain.  相似文献   
109.
AIM: To define the magnetic resonance imaging (MRI) parameters differentiating urethral hypermobility (UH) and intrinsic sphincter deficiency (ISD) in women with stress urinary incontinence (SUI).METHODS: The static and dynamic MR images of 21 patients with SUI were correlated to urodynamic (UD) findings and compared to those of 10 continent controls. For the assessment of the urethra and integrity of the urethral support structures, we applied the high-resolution endocavitary MRI, such as intraurethral MRI, endovaginal or endorectal MRI. For the functional imaging of the urethral support, we performed dynamic MRI with the pelvic phased array coil. We assessed the following MRI parameters in both the patient and the volunteer groups: (1) urethral angle; (2) bladder neck descent; (3) status of the periurethral ligaments, (4) vaginal shape; (5) urethral sphincter integrity, length and muscle thickness at mid urethra; (6) bladder neck funneling; (7) status of the puborectalis muscle; (8) pubo-vaginal distance. UDs parameters were assessed in the patient study group as follows: (1) urethral mobility angle on Q-tip test; (2) Valsalva leak point pressure (VLPP) measured at 250 cc bladder volume; and (3) maximum urethral closure pressure (MUCP). The UH type of SUI was defined with the Q-tip test angle over 30 degrees, and VLPP pressure over 60 cm H2O. The ISD incontinence was defined with MUCP pressure below 20 cm H2O, and VLPP pressure less or equal to 60 cm H2O. We considered the associations between the MRI and clinical data and UDs using a variety of statistical tools to include linear regression, multivariate logistic regression and receiver operating characteristic (ROC) analysis. All statistical analyses were performed using STATA version 9.0 (StataCorp LP, College Station, TX).RESULTS: In the incontinent group, 52% have history of vaginal delivery trauma as compared to none in control group (P < 0.001). There was no difference between the continent volunteers and incontinent patients in body habitus as assessed by the body mass index. Pubovaginal distance and periurethral ligament disruption are significantly associated with incontinence; periurethral ligament symmetricity reduces the odds of incontinence by 87%. Bladder neck funneling and length of the suprapubic urethral sphincter are significantly associated with the type of incontinence on UDs; funneling reduced the odds of pure UH by almost 95%; increasing suprapubic urethral sphincter length at rest is highly associated with UH. Both MRI variables result in a predictive model for UDs diagnosis (area under the ROC = 0.944).CONCLUSION: MRI may play an important role in assessing the contribution of hypermobility and sphincteric dysfunction to the SUI in women when considering treatment options.  相似文献   
110.
Active pronation is important for many activities of daily living. Loss of median nerve function including pronation is a rare sequela of humerus fracture. Tendon transfers to restore pronation are reserved for the obstetrical brachial plexus palsy patient. Transfer of expendable motor nerves is a treatment modality that can be used to restore active pronation. Nerve transfers are advantageous in that they do not require prolonged immobilization postoperatively, avoid operating within the zone of injury, reinnervate muscles in their native location prior to degeneration of the motor end plates, and result in minimal donor deficit. We report a case of lost median nerve function after a humerus fracture. Pronation was restored with transfer of the extensor carpi radialis brevis branch of the radial nerve to the pronator teres branch of the median nerve. Anterior interosseous nerve function was restored with transfer of the supinator branch to the anterior interosseous nerve. Clinically evident motor function was seen at 4 months postoperatively and continued to improve for the following 18 months. The patient has 4+/5 pronator teres, 4+/5 flexor pollicis longus, and 4−/5 index finger flexor digitorum profundus function. The transfer of the extensor carpi radialis brevis branch of the radial nerve to the pronator teres and supinator branch of the radial nerve to the anterior interosseous nerve is a novel, previously unreported method to restore extrinsic median nerve function.  相似文献   
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