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991.

Purpose

The place of arthroscopic treatment in osteoarthritis of the knee has generated much controversy. A survey was initiated to collect the opinion of experienced surgeons.

Methods

Of the 211 surgeons interviewed, 170 (80.6 %) replied to the electronic questionnaire. Respondents had at least ten years of experience in arthroscopy and currently perform more than 100 arthroscopies per year. Various indications and treatment modalities for arthroscopy in osteoarthritis of the knee had to be evaluated on a scale from “excellent” to “no indication”.

Results

The respondents generally believe that an improvement is more likely in low-grade osteoarthritis (p < 0.001) and in neutral leg axis (p < 0.001). The outcome was rated better if symptoms had persisted for less than six months (p < 0.001) and for patients that were younger than 60 years (p < 0.001). Partial meniscectomy and notchplasty in cases of extension deficit were considered as successful treatment options. Debridement was an accepted indication, with an outcome mainly rated as fair. A majority saw no indication for joint lavage, arthroscopic treatment of arthrofibrosis and removal of osteophytes. The outcome appears to be poor if a bone edema is diagnosed on magnetic resonance imaging prior to arthroscopy. Only 55.9 % of respondents were comfortable with the current definition of osteoarthritis.

Conclusions

Experienced arthroscopic surgeons all over Europe believe arthroscopy in osteoarthritis is appropriate, under certain conditions. The major task for surgeons is to select the right patients who are likely to benefit from this intervention.  相似文献   
992.

Purpose

Excellent long-term results have been reported for implantation of unicompartmental knee arthroplasty (UKA). In many patients the desire for improvement in function often includes an aspiration to return to sports. The purpose of our study was to evaluate physical activities after medial Oxford-III (Biomet) UKA surgery.

Methods

Patients’ physical activity before and after the surgery was assessed using a self reporting questionnaire. We used the Oxford knee scoring system (OKS), the WOMAC-, the Knee society- (KSS) and the UCLA-score to assess postoperative knee function. The mean follow-up was 4.2 years. The female-to-male ratio was 1.3:1. The mean age at surgery was 65.3 years.

Results

Of the 131 patients studied 78 participated in some kind of sports before surgery (mean age 64.4 years), while 53 patients did not perform any sports (mean age 66.5 years) (p > 0.05). At follow-up the patients in the active group were significantly younger than the patients in the inactive group (p < 0.05). The majority of patients (80.1 %) returned to their level of sports activity after UKA surgery. Six patients took up sports after surgery while 15 patients stopped their sports. Among the active patients we found a shift from high- towards low-impact sports. The active patients had significantly higher scores for the OKS, KSS, WOMAC and UCLA score. The complication rate was comparable in both groups.

Conclusion

Our study demonstrates that a high degree of patient satisfaction in terms of sports activity can be achieved using the Oxford-III UKA for medial osteoarthritis.  相似文献   
993.

Purpose

Desmoid tumours of the extremity have a high recurrence rate. The purpose of this study was to analyse the outcome after resection of these tumours with special emphasis on recurrent disease and adjuvant therapeutic strategies.

Methods

In this retrospective study we evaluated prognostic factors for recurrence-free survival after surgical treatment of desmoid tumours of the extremity in 27 patients with an average age of 41 years treated from 1997 to 2009. Adjuvant radiotherapy (50–60 Gy) was given in five cases with primary and in nine patients with recurrent disease. The average follow-up was 64 months.

Results

The five-year recurrence-free survival in patients with primary disease was 33 %. Patients with negative resection margins tended to have a better outcome than patients with positive resection margins, but the difference between both groups was not significant (56 vs 14 %, p = 0.145). In patients with positive margins, adjuvant radiotherapy did not significantly improve recurrence-free survival (40 vs 14 %, p = 0.523). Patients with local recurrence had a five-year further recurrence-free survival of 47 %. In those patients further recurrence-free survival was significantly better after adjuvant radiation (89 vs 25 %, p = 0.015). Two thirds of all patients suffered moderate or severe complications due to the treatment regimen.

Conclusions

Compared to desmoids of the trunk or the head and neck region, desmoids affecting the limbs show by far the worst outcome in terms of relapse or treatment-related morbidity. The importance of negative resection margins is still not clear. Particularly in recurrent desmoids adjuvant radiotherapy appears to reduce the further recurrence rate. Therefore, a general use of radiation should be considered for this high-risk group.  相似文献   
994.
995.
996.

Background

In this study, we evaluate a new bioadhesive for intra-abdominal onlay mesh fixation of a polypropylene–polyvinylchloride graft.

Methods

Three pieces of a commercially available polypropylene/polyvinylfluoride mesh, each 3 × 3 cm in size, and three pieces of the same mesh coated with a polysaccharide bioadhesive were fixated to the surface of the anterior abdominal wall of 30 New Zealand white rabbits. The fixation was performed either by using four transabdominal Prolene® 4/0 sutures, four spiral tacks (Protack 5 mm Tyco), or cyanoacrylate glue (Glubran® GEM, Viareggio, Italy). Each mesh position and the according kind of fixation were randomized before implantation. The animals were sacrificed 12 weeks postoperatively. After determining the extent of intra-abdominal adhesions, the meshes were excised en bloc with the anterior abdominal wall for tensile strength measurements and histological analysis.

Results

All meshes coated with the bioadhesive adhered to the intact peritoneum without extra fixation. Irrespective of the fixation technique coated meshes led to more and stronger adhesions. Mesh shrinkage by scarring was increased in coated meshes fixed with glue and low in uncoated meshes fixed with tacks. Testing the tensile strength, coated meshes fixed with transfascial sutures achieved the best results (16.14 ± 6.1 N), whereas coated meshes fixed with glue showed the lowest strength (10.39 ± 4.81 N). The foreign body reaction was considerably more distinctive using coated mesh. The mesh ingrowth was not influenced by this reaction.

Conclusions

All meshes coated with the new bioadhesive were self-adhesive in that way; they stayed in position when attached to the peritoneum. Although this may facilitate intra-operative mesh fixation, the bioadhesive displayed several disadvantages, such as stronger adhesions and an increased shrinkage of the implant. The tensile strength was not influenced by the use of the bioadhesive. At present, we see no major advantage for polysaccharide bioadhesive applied in this study.  相似文献   
997.

Background

Navigation systems potentially facilitate minimally invasive esophagectomy and improve patient outcome by improving intraoperative orientation, position estimation of instruments, and identification of lymph nodes and resection margins. The authors’ self-developed navigation system is highly accurate in static environments. This study aimed to test the overall accuracy of the navigation system in a realistic operating room scenario and to identify the different sources of error altering accuracy.

Methods

To simulate a realistic environment, a porcine model (n = 5) was used with endoscopic clips in the esophagus as navigation targets. Computed tomography imaging was followed by image segmentation and target definition with the medical imaging interaction toolkit software. Optical tracking was used for registration and localization of animals and navigation instruments. Intraoperatively, the instrument was displayed relative to segmented organs in real time. The target registration error (TRE) of the navigation system was defined as the distance between the target and the navigation instrument tip. The TRE was measured on skin targets with the animal in the 0° supine and 25° anti-Trendelenburg position and on the esophagus during laparoscopic transhiatal preparation.

Results

On skin targets, the TRE was significantly higher in the 25° position, at 14.6 ± 2.7 mm, compared with the 0° position, at 3.2 ± 1.3 mm. The TRE on the esophagus was 11.2 ± 2.4 mm. The main source of error was soft tissue deformation caused by intraoperative positioning, pneumoperitoneum, surgical manipulation, and tissue dissection.

Conclusion

The navigation system obtained acceptable accuracy with a minimally invasive transhiatal approach to the esophagus in a realistic experimental model. Thus the system has the potential to improve intraoperative orientation, identification of lymph nodes and adequate resection margins, and visualization of risk structures. Compensation methods for soft tissue deformation may lead to an even more accurate navigation system in the future.  相似文献   
998.

Introduction

Persistent horizontal instability after acute acromioclavicular (AC) joint separation may provoke unsatisfactory results of conservative treatment. Hypothesis: the arthroscopically assisted double flip button stabilization of acute horizontally unstable grade III and IV AC joint disruptions results in full functional restoration and stable radiological reposition.

Materials

21 patients treated for an acute grade III or IV AC joint separation were enrolled. Clinical assessment at least 2-year postoperative included the constant score (CS) and the simple shoulder test. A panorama stress view, bilateral axial view and an AC view were obtained for radiographic evaluation.

Results

19 individuals (mean 37 years; 17 men) with 16 Rockwood type III and 3 type IV injuries were available for examination 24–51 months postoperatively. The mean CS was 90.2 points (SD 6.5) with no statistically significant difference between CS and age-adjusted normative values. The mean Simple Shoulder Test scored 11.5 points (range 8–12). Loss of reduction of more than 2 mm in the coronal plane stress views was present in 6 patients (32 %) with no associated loss of functional outcome. Two of four reported complications in four patients were treated surgically (one open revision with graft augmentation for coracoid implant break out, one arthroscopic capsular release for persistent glenohumeral stiffness).

Conclusion

Arthroscopically assisted double flip button stabilization for acute grade III and IV AC joint separation restores fully horizontal stability and age-expected shoulder function, resulting in high patient satisfaction, despite a loss of reduction observed radiographically in approximately one-third of patients.

Level of evidence

IV.  相似文献   
999.

Introduction

The aim of the study was to identify risk factors of failed two-stage procedures in cases of chronic posttraumatic periprosthetic hip infections.

Patients and methods

Between 2006 and 2008, 26 patients with chronic posttraumatic periprosthetic infections after hip arthroplasty were included. In all cases operative bacterial eradication was initiated. The therapy was carried out according to a standardized treatment protocol including the eradication of the bacterial infection and the prosthetic replacement after three negative intra-operative specimens as a two-stage procedure. Follow-up was performed at least 2 years after revision procedure.

Results

Twelve patients showed no signs of infectious recurrence 2 years after prosthetic hip revision therapy (46 %) and were assigned to group I. Group II is constituted by the other 14 patients (54 %). Four of them (16 %) suffered from an infectious recurrence after prosthetic hip replacement, ten patients (38 %) were characterised by a failed bacterial eradication. The spectrum of pathogens showed a significantly higher resistance pattern (p = 0.001) in group II, with a majority of methicillin-resistant Staphylococcus epidermidis (MRSE) and highly resistant Pseudomonas. In addition, patients of group II offered significantly higher American Society of Anesthesiology (ASA) scores (p = 0.015), the body mass index (BMI) was significantly elevated (p = 0.031) and received a significantly higher number of operative procedures (p = 0.016).

Conclusions

A reduced general state of health, a high BMI and highly resistant pathogens are the main risk factors for a failed two-stage procedure after chronic posttraumatic periprosthetic hip infections. Therefore, different treatment strategies are required for a defined subgroup of patients.  相似文献   
1000.

Background

The serum neutrophil–lymphocyte ratio (NLR) is associated with outcomes in several solid organ cancers, including hepatocellular carcinoma (HCC).

Methods

We reviewed our experience in patients with HCC who underwent transarterial chemoembolization (TACE) as the initial treatment. Serum complete blood counts were used to calculate the NLR before and after TACE. The Kaplan–Meier method was used to determine survival and significant differences between groups by the log-rank test.

Results

There were 103 patients identified who underwent TACE for HCC. The median age was 60.5 years. Median overall survival was 12.6 (95 % confidence interval 8.3–17) months. Median survival in patients with a high preprocedural NLR was 4.2 months compared to 15 months in those with a normal NLR (p = 0.021). In those whose NLR either rose 1 month after treatment or remained elevated, survival was worse compared to those who normalized or remained normal (18.6 vs. 10.6 months, p = 0.026). The same was true at 6 months (21.3 vs. 9.5 months, p = 0.002). An unresponsive NLR was associated with very poor outcome (median survival 3.7 months). Multivariate analysis of clinicopathologic factors showed that presence of extrahepatic disease and high NLR were independent factors associated with worse survival.

Conclusions

Our study demonstrates that periprocedural trends of serum NLR are associated with outcome in unresectable HCC undergoing TACE. Serum NLR is easy to calculate from a routine complete blood count with differential. Along with liver function, serum NLR may be helpful to clinicians in providing prognostic information and monitoring response to therapy.  相似文献   
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