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Torsten Wredmark

Publications and source records attributed to Torsten Wredmark.

9 recordsLinked to original sources
PubMed2006

Hamstring tendons regeneration after ACL reconstruction: an overview.

Despite the long lasting research the ideal method of reconstructing the ACL has not been found so far. The last year's attention has shifted to the use of the multistrand hamstring tendon grafts. High ultimate tensile load, multiple-bundle replacement that better approximates the anatomy of the normal ACL and low donor site morbidity are the main advantages of this ACL replacement graft. These theoretical advantages have been multiplied when surprisingly studies have shown that semitendinosus and gracilis tendons actually regenerate after harvesting for use as ACL autografts. In this review article we summarize the current knowledge concerning the hamstring regeneration and we focus on issues that have clinical relevance or issues that have not been answered so far.

Anterior Cruciate Ligament↗
PubMed2006

Visuospatial abilities correlate with performance of senior endoscopy specialist in simulated colonoscopy.

Visuospatial abilities have been demonstrated to predict the performance of medical students in simulated endoscopy. However, little has been reported whether differences in visuospatial abilities influence the performance of senior endoscopists or whether their vast endoscopy experience reduces the importance of these abilities. Eleven senior endoscopists were included in our study. Before the simulated endoscopies in GI Mentor II (gastroscopy: case 3, module 1 and colonoscopy: case 3, module 1), the endoscopists performed three visuospatial tests: (1) pictorial surface orientation (PicSOr), (2) card rotation, and (3) cube comparison tests that monitor the ability of the tested person to re-create a three-dimensional image from a two-dimensional presentation as well as mentally manipulate that re-created image. The results of the visuospatial tests were correlated to the performance parameters of the virtual-reality endoscopy simulator. The percent of time spent with clear view in the simulated colonoscopy correlated well with the performance in the visuospatial PicSOr (r = -0.75, P = 0.01), card rotation (r = 0.75, P = 0.01), and cube comparison (r = 0.79, P = 0.004) tests. The endoscopists who performed better in the visuospatial tests also were better at maintaining visualization of the colon lumen. Those who performed better in the PicSOr test formed fewer loops during colonoscopy (r = 0.60, P = 0.05). In the technically less demanding simulated gastroscopy, there were no such correlations. The visuospatial tests performed better in endoscopists not playing computer games. Good visuospatial ability correlates significantly with the performance of experienced endoscopists in a technically demanding simulated colonoscopy, but not in the less demanding simulated gastroscopy.

Adult↗
PubMed2006

Opioid requirement after arthroscopy is associated with decreasing glucose levels and increasing PGE2 levels in the synovial membrane.

BACKGROUND: Increased prostaglandin E2 (PGE2) release has been suggested to contribute to the enhanced nociceptor sensitivity that underlies chronic osteoarthritis pain. We have previously shown increased levels of lactate and glycerol in synovium postoperatively. Thus, we wanted to investigate whether the local trauma response is related to subjective pain. METHODS: We monitored metabolic and inflammatory changes with microdialysis in the knee joint synovial membrane of 14 patients after arthroscopy, in relation to pain requiring systemic opioids. The adipose tissue of the contralateral thigh served as reference. The concentrations of glucose, lactate, pyruvate, glycerol and PGE2, and also local blood flow were analyzed over 3 hours postoperatively. RESULTS: In the 6 patients requiring systemic opioid analgesia, the initial concentrations of glucose and PGE2 in the synovial tissue were increased compared to those not requiring opioids, and decreased following opioid administration. In the reference tissue there was no difference between groups regarding glucose, and the PGE2 concentration was below the detection limit. No significant differences in the levels of other compounds, in relation to the need for opioids, were found, either in synovial tissue or in reference tissue. Overall, the synovial tissue blood flow was stable. INTERPRETATION: Pain after arthroscopy is reflected by increased glucose utilization and PGE2 production by the synovial membrane.

Adolescent↗
PubMed2006

Working memory and image guided surgical simulation.

We report on a study that investigates the relationship between visual working memory and verbal working memory and a performance measure in endoscopic instrument navigation in MIST and GI Mentor II (a simulator for gastroendoscopy). Integrated cognitive neuroscience in state-of-the-art simulator training curriculum will take safety science in health care one step ahead. Current simulator validation focuses on how to train. In the light of recent research it is now prime time to ask why in search of mechanisms rather than to repeatedly show that training has effect. This will help tailor training to maximize individual output in procedures that require a high level of dexterity. WM training is a unique learning aid in simulator training and should be used alongside clinical practice in order to improve the quality of complex clinical intervention in the field of image guided surgical simulation.

Computer Simulation↗
PubMed2005

Changes in metabolism and blood flow following catecholamine stimulation in the synovial membrane measured with microdialysis.

Adrenergic reactions could mediate metabolic and circulatory changes in the synovial membrane following knee surgery. The interstitial fluid of the synovial membrane and subcutaneous adipose tissue (reference) was monitored in vivo with microdialysis following knee arthroscopy with adrenaline added to the dialysis solvent, adrenaline together with a local anestetic added intra-articularly and without. Local metabolism and blood flow were measured. There was a similar increase, about two fold, in dialysate lactate in all three experimental conditions in the synovial membrane but no change in adipose tissue. Glucose and blood flow decreased by approximately 50% and 10% in both tissues following addition of adrenaline to the dialysate but no changes in the glucose concentrations or blood flow were observed in the other two experimental situations. As regards glycerol the addition of adrenaline caused an approximate 20% increase of the concentration in adipose tissue but an approximate 20% decrease in the synovial membrane. The intra-articular injection caused an approximate 50% increase of the glycerol level in the synovial membrane but no change in adipose glycerol. Thus, the hypermetabolic state in the synovial membrane following standard arthroscopy and the tissue damage (increased glycerol level) in the synovial membrane following postoperative pain relief by intra-articularly injected local anesthetics together with adrenaline doesn't enhance the hypermetabolic state seen postoperatively without adrenaline. However, catecholamines have pronounced in vivo effects on metabolism and blood flow in the synovial membrane.

Adipose Tissue↗
PubMed2004

Visuospatial skills and computer game experience influence the performance of virtual endoscopy.

Advanced medical simulators have been introduced to facilitate surgical and endoscopic training and thereby improve patient safety. Residents trained in the Procedicus Minimally Invasive Surgical Trainer-Virtual Reality (MIST-VR) laparoscopic simulator perform laparoscopic cholecystectomy safer and faster than a control group. Little has been reported regarding whether factors like gender, computer experience, and visuospatial tests can predict the performance with a medical simulator. Our aim was to investigate whether such factors influence the performance of simulated gastroscopy. Seventeen medical students were asked about computer gaming experiences. Before virtual endoscopy, they performed the visuospatial test PicCOr, which discriminates the ability of the tested person to create a three-dimensional image from a two-dimensional presentation. Each student performed one gastroscopy (level 1, case 1) in the GI Mentor II, Simbionix, and several variables related to performance were registered. Percentage of time spent with a clear view in the endoscope correlated well with the performance on the PicSOr test (r = 0.56, P < 0.001). Efficiency of screening also correlated with PicSOr (r = 0.23, P < 0.05). In students with computer gaming experience, the efficiency of screening increased (33.6% +/- 3.1% versus 22.6% +/- 2.8%, P < 0.05) and the duration of the examination decreased by 1.5 minutes (P < 0.05). A similar trend was seen in men compared with women. The visuospatial test PicSOr predicts the results with the endoscopic simulator GI Mentor II. Two-dimensional image experience, as in computer games, also seems to affect the outcome.

Case-Control Studies↗