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91.
Although tension-free techniques of hernia repair using synthetic meshes have yielded encouraging results, the best method of inguinal hernia repair is still unclear. The aim of this study was to compare the responses of inflammatory mediators and postoperative pain relief following laparoscopic total extraperitoneal (TEP) hernioplasty, open tension-free mesh hernioplasty (Lichtenstein), posterior preperitoneal mesh hernioplasty (Nyhus procedure), and Bassini procedure. Patients with primary inguinal hernia were randomized in the operating room to undergo one of these repair techniques. Group I comprised 24 patients treated by Lichtenstein procedure; Group II comprised 21 patients treated by Nyhus procedure; Group III comprised 19 patients treated by Bassini procedure; and Group IV comprised 20 patients treated by laparoscopic TEP mesh hernioplasty. Postoperative pain levels following hernia repair were compared by measuring the use of patient-controlled analgesia (PCA) during the 24 hours after surgery. Serum samples withdrawn before surgery and 48 hours after surgery were assayed for C-reactive protein (CRP) content. Patient characteristics, operating time, and operative and early complications were noted. Serum CRP levels rose markedly following Nyhus (184.5 +/- 41.6 mg/L), Lichtenstein (138.4 +/- 72.5 mg/L), and Bassini repair (137.2 +/- 55.9 mg/L) compared with that of patients who underwent TEP mesh hernioplasty (55.5 +/- 41.2 mg/L). There were also significant differences in the postoperative need for analgesics via PCA among patients undergoing Nyhus (382.9 +/- 189.1 mg), Bassini (303.2 +/- 173.7 mg), and Lichtenstein (253.9 +/- 129.3) procedures compared with 196.6 +/- 148.8 mg for the TEP mesh hernioplasty group. Patients in the Lichtenstein group also had significantly less need of analgesics than those in the Nyhus and Bassini groups. In conclusion, TEP mesh hernioplasty is less traumatic and yields less postoperative pain than the Nyhus, Lichtenstein, and Bassini procedures.  相似文献   
92.
Background: The antidepressant amitriptyline is commonly used orally for the treatment of chronic pain, particularly neuropathic pain, which is thought to be caused by high-frequency ectopic discharge. Among its many properties, amitriptyline is a potent Na+ channel blocker in vitro, has local anesthetic properties in vivo, and confers additional blockade at high stimulus-discharge rates (use-dependent blockade). As with other drug modifications, adding a phenylethyl group to obtain a permanently charged quaternary ammonium derivative may improve these advantageous properties.

Methods: The electrophysiologic properties of N-phenylethyl amitriptyline were assessed in cultured neuronal GH3 cells with the whole cell mode of the patch clamp technique, and the therapeutic range and toxicity were evaluated in the rat sciatic nerve model.

Results: In vitro, N-phenylethyl amitriptyline at 10 [mu]m elicits a greater block of Na+ channels than amitriptyline (resting block of approximately 90%vs. approximately 15%). This derivative also retains the attribute of amitriptyline in evoking high-degree use-dependent blockade during repetitive pulses. In vivo, duration to full recovery of nociception in the sciatic nerve model was 1,932 +/- 72 min for N-phenylethyl amitriptyline at 2.5 mm (n = 7) versus 72 +/- 3 min for lidocaine at 37 mm (n = 4; mean +/- SEM). However, there was evidence of neurotoxicity at 5 mm.  相似文献   

93.
A conflict exists on whether the ligamentum capitis femoris has the neuro-morphological structures required for nociception or proprioception of the hip joint. Therefore, we investigated the morphological features and the presence of mechanoreceptors in 24 ligamentum capitis femoris biopsies obtained at open reduction in patients with developmental dysplasia of the hip. Of these 24 hips, 16 were completely dislocated and eight were subluxated. The mean age was 33.8 months (range 13-52 months) at the time of surgery. En bloc ligamentum capitis femoris and pulvinar were taken for biopsy specimen. Ligamentum capitis femoris was dissected and the weight of each ligament was determined using a highly sensitive balance. Specimens were stained with hematoxylin and eosin and Masson trichrome for routine histolopathological evaluation and examined immunohistochemically using monoclonal antibody against S-100 protein. All specimens were graded on a four-grade system according to the amount of coarse-thick collagen bundles and hyalinization. The mean number and type of mechanoreceptors of each specimen were recorded. When the mean age, the patient's weight and the ligamentum capitis femoris weight of each group (completely dislocated vs. subluxated) were compared, there were no significant differences. In the ligamentum capitis femoris of the dislocated hips, the cells were irregularly distributed, had different shapes, and appeared to be in different stages of functional activity. The collagen fiber bundles were thicker than in the subluxated hips, distributed and of varied thickness. The elastic fibers of the dislocated hips were thicker and more numerous than those in the subluxated hips. We found a significant difference between the two groups with regard to the grade of collagen and hyalinization of ligamentum capitis femoris (P<0.004). We found type IVa, free nerve endings in 16 of 24 samples of ligamentum capitis femoris. The 66.6% presence of free nerve endings in the ligamentum capitis femoris suggests a role in nociception/proprioception of the hip in developmental dysplasia of the hip. Interestingly, the percentage and the mean numbers of free nerve endings containing ligamentum capitis femoris were similar in completely dislocated hip group and the subluxated group (62.5 vs. 75%, 12.13+/-9.07 vs. 9.37+/-9.24, respectively). We conclude that the morphological features of ligamentum capitis femoris are influenced by the severity of developmental dysplasia of the hip, whereas the distribution of free nerve endings are not influenced.  相似文献   
94.
95.
The purpose of this study was to assess the prevalence of female urinary incontinence (UI) and risk factors of bothersomeness and help-seeking behavior of hidden female UI in urology and obstetrics and gynecology outpatient clinics. This multicentric and cross-sectional study was conducted as a part of the Turkish Overactive Bladder Study. Female patients (n = 5,565) who were referred with complaints other than UI and overactive bladder symptoms were surveyed using the International Consultation on Incontinence Questionnaire Short Form (ICIQ-SF) with supplementation of five more questions. The crude prevalence of UI was found to be 35.7%. The prevalence of frequent and severe incontinence was 8.2 and 6.8%, respectively. The mean age of incontinent patients was significantly higher (p < 0.001). The prevalence of stress, urge, and mixed UI was 39.8, 24.8, and 28.9%, respectively. More than half (53%) of incontinent patients were not bothered by UI, and only 12% of incontinent patients had previously sought medical help for their problem. Frequency, severity, and type of UI were independent factors for predicting bothersome UI, while only bothersomeness increased help-seeking behavior. The ICIQ-SF score of 8 has been found to be the best cutoff value to delineate the bothersome UI. Although the crude prevalence of female UI was found to be high, bothersome UI was not so common. The majority of incontinent female patients did not seek medical help. Frequency, severity, and mixed type of UI were found to be the determinants of bothersome UI for which the ICIQ-SF cutoff score of 8 was obtained.  相似文献   
96.
Background Pyrrolidine dithiocarbamate (PDTC) is a low-molecular-weight thiol antioxidant and potent inhibitor of nuclear factor-κB (NF-κB) activation. It has been shown to attenuate local harmful effects of ischemia/reperfusion (I/R) injury in many organs. In recent animal studies, a delaying effect of remote organ I/R injury on the healing of colonic anastomoses has been demonstrated. In this study we investigated whether PDTC prevents harmful systemic effects of superior mesenteric I/R on left colonic anastomosis in rats. Methods Anastomosis of the left colon was performed in 40 rats randomly allocated into the following four groups: (1) Sham-operated group (group I, n = 10)—simultaneously with colonic anastomosis, the superior mesenteric artery and collateral branches divided from the celiac axis and the inferior mesenteric artery were isolated but not occluded. (2) Sham+PDTC group (group II, n = 10)—identical to sham-operated rats except for the administration of PDTC (100 mg/kg IV bolus) 30 minutes prior to commencing the experimental period. (3) I/R group (group III, n = 10)—60 minutes of intestinal I/R by superior mesenteric artery occlusion. (4) PDTC-treated group (group IV, n = 10)—PDTC 100 mg/kg before and after the I/R. On postoperative day 6, all animals were sacrificed, and anastomotic bursting pressures were measured in vivo. Tissue samples were obtained for investigation of anastomotic hydroxyproline (HP) contents, perianastomotic malondialdehyde (MDA) levels, myeloperoxidase activity (MPO), and glutathione (GSH) level. Results There was a statistically significant decrease in anastomotic bursting pressure values, tissue HP content and GSH level, along with an increase in MDA level and MPO activity in group III, when compared to groups I, II, and IV (p < 0.05). However, PDTC treatment led to a statistically significant increase in anastomotic bursting pressure values, tissue HP content and GSH level, along with a decrease in MDA level and MPO activity in group IV (p < 0.05). Conclusions This study showed that PDTC treatment significantly prevented the delaying effect of remote organ I/R injury on anastomotic healing in the colon. Further clinical studies are needed to clarify whether PDTC may be a useful therapeutic agent for increasing the safety of the anastomosis during particular operations where remote organ I/R injury occurs.  相似文献   
97.
Introduction Shortening the period of time for the external fixator after limb lengthening decreases the complication rate and increases the patient satisfaction. Material and method We describe the plating after lengthening (PAL) as a new technique on five patients with limb length discrepancy (1 femoral, 4 tibial) who had lengthening procedure with Ilizarov technique. The mean amount of lengthening was 50 mm. The mean lengthening period was 100 days (5–135 days). When the lengthening period ended, the locking compression plate was applied percutaneously by using the technique of minimal invasive plate osteosynthesis, and the Ilizarov external fixator was removed. Results The fixator-free period was achieved at the beginning of the consolidation phase, except in two patients, which were delayed for plating because of pin-tract infection. No complication was encountered except in one patient who had limited flexion of knee joint. There was no need for blood transfusion. Discussion The PAL, which shortened the period of time for the external fixator, was an easy and safe method for the fixation of the bone after limb lengthening.  相似文献   
98.
BACKGROUND CONTEXT: Intraoperative somatosensory evoked potential (SSEP) monitoring has been shown to reduce the incidence of new postoperative neurological deficits in scoliosis surgery. However, its usefulness during cervical spine surgery remains a subject of debate. PURPOSE: To determine the utility of intraoperative SSEP monitoring in a specific patient population (those with cervical radiculopathy in the absence of myelopathy) who underwent anterior cervical discectomy and fusion (ACDF) surgery. STUDY DESIGN: Retrospective review. PATIENT SAMPLE: A total of 1,039 nonmyelopathic patients who underwent single or multilevel ACDF surgery. The control group (462 patients) did not have intraoperative SSEP monitoring, whereas the monitored group (577 patients) had continuous intraoperative SSEP monitoring performed. OUTCOME MEASURE: A new postoperative neurological deficit. METHODS: SSEP tracings were reviewed for all 577 patients in the monitored group and all significant signal changes were noted. Medical records were reviewed for all 1,039 patients to determine if any new neurological deficits developed in the immediate postoperative period. RESULTS: None of the patients in the control group had any new postoperative neurological deficits. In the monitored group there were six instances of transient SSEP changes (1 due to suspected carotid artery compression; 5 thought to be due to transient hypotension) which resolved with the appropriate intraoperative intervention (repositioning of retractors; raising the arterial blood pressure). Upon waking up from anesthesia, one patient in the monitored group had a new neurological deficit (partial central cord syndrome) despite normal intraoperative SSEP signals. CONCLUSIONS: ACDF appears to be a safe surgical procedure with a low incidence of iatrogenic neurological injury. Transient SSEP signal changes, which improved with intraoperative interventions, were not associated with new postoperative neurological deficits. An intraoperative neurological deficit is possible despite normal SSEP signals.  相似文献   
99.
BACKGROUND: Among all lumbar disc herniations, L5-S1 far-lateral disc herniations are rare entities. Besides, surgical approach may be difficult because of the very narrow passage at this level. For these 2 reasons, most spine surgeons are not experienced in herniations at this level. According to new microanatomic studies, previous lateral approaches at this level often do not allow access to the neuroforamen without partial or total destruction of the L5-S1 facet joint. To preserve the facet joint, an approach was developed. PURPOSE: To assess the efficacy of a surgical technique that is a minimally invasive intermuscular approach (MIIMA) for decompression of L5-S1 far-lateral level disc herniation (FLLDH). STUDY DESIGN: We present a prospective clinical study analysis of 14 patients with L5-S1 far-lateral disc herniations in a period between 2000 and 2004, treated with microsurgical technique. METHODS: An imaging study revealed consistency with the patient's clinical presentation. In our department, a total of 580 patients underwent discectomy between 2000 and 2004 for lumbar disc herniation. RESULT: Twenty-eight patients had foraminal or extraforaminal herniations (4.8%). Fourteen patients had FLLDH at the L4-L5 level (2.4%), whereas the other 14 were cases of FLLDH at the L5-S1 level (2.4%). One patient had FLLDH at both L5-S1 and L4-L5 levels (7.1%). The mean age of patients was 53.6 years, and the male:female ratio was approximately 5:9. All patients failed to recover after at least 6 weeks of conservative therapy. The mean duration of symptoms until the time of surgery was 7.2 months. Using this MIIMA technique, the authors removed the herniated discs compressing the (L5) nerve roots. Clinical outcome was measured using the visual analog scale. Every patient was discharged within 24 hours. Satisfactory (excellent or good) results were demonstrated in 13 patients (92.9%), because, except for 1 (7.1) permanent dysesthesia case, 4 cases (21.3%) were temporary dysesthesia. Postoperatively all patients reported excellent relief of their sciatic pains, and there were no technique-associated complications. No recurrence was observed during the follow-up period ranging from 10 to 60 months (mean, 29 mo). This is one of the major complications of any approach to a far-lateral disc. CONCLUSIONS: The authors describe a MIIMA for excising herniated discs that is applicable to all types of far-lateral lumbar herniations. Postoperative dysesthesia is the most important complication and may persist as it did in our cases. Consequently, manipulation of the ganglion should be avoided at all costs, if possible. The MIIMA procedure provides a simple alternative for treating lumbar foraminal or lateral exit zone herniated discs in selected cases. This approach is effective, allowing the preservation of the L5-S1 facet joint, saving the facet joint, preventing postoperative instability, and offering a direct view of the L5-S1 neuroforamen.  相似文献   
100.
Pediatric robotic surgery: lessons from a clinical experience   总被引:1,自引:0,他引:1  
PURPOSE: Robotic surgery may improve minimally invasive surgery at high magnification by tremor filtration, motion-scaling, and improved dexterity with the provision of a wrist at the end of the robotic instrument. MATERIALS AND METHODS: We chose the Zeus Microwrist robotic surgical system as more applicable to small children than the competing da Vinci surgical system. We attempted 57 surgical procedures and completed 54. RESULTS: Completed procedures included Nissen fundoplication (n = 25), cholecystectomy (n = 18), Heller myotomy (n = 2), splenectomy (n = 2), Morgagni hernia repair (n = 2), and single cases of complex pyloroplasty in the chest, bowel resection, left Bochdalek congenital diaphragmatic hernia repair, esophageal atresia and tracheoesophageal fistula repair, and choledochal cyst excision. There were no complications related to the use of the robot. The mean time for the surgeon at the console using the robot was 117 +/- 39 minutes for Nissen fundoplication, and the total operating room time was 250 +/- 60 minutes. Surgeons found dissection, suturing, and knot tying easier than with conventional laparoscopy. None of the surgeons thought the lack of touch feedback (haptics) was crucial. CONCLUSION: Robotic surgery offers increased dexterity to the pediatric minimally invasive surgeon, but procedures require more time, and there is no defined patient benefit. The fact that robotic surgery digitalizes minimally invasive surgery creates exciting possibilities for training surgeons, planning operations, and performing surgery at great distances from the operator.  相似文献   
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