[Clinical relevance of a routinely performed magnetic resonance cholangiopancreatography (MRCP) prior to cholecystectomy]. / Klinische Wertigkeit einer routinemäßigen Magnetresonanz-Cholangiopankreatikografie (MRCP) vor Cholezystektomie.

BACKGROUND: A preoperative diagnostic imaging procedure is essential for therapy in cholecystolithiasis. According to the S3-Guidelines of the German Society for General and Visceral Surgery only an ultrasound scan is needed before a cholecystectomy. But an anatomic variant of the bile ducts or choledocholithiasis is poorly shown by an ultrasound. Because of this, we performed a magnetic resonance cholangiopancreatography (MRCP) routinely. This study was designed to show if the MRCP changed the treatment plan or changed the operation method. Furthermore, the sensitivity and specificity concerning abnormalities of the cystic duct, accessory bile ducts and choledocholithiasis should be determined. PATIENTS AND METHODS: During the time between January 1st 2005 and September 30th 2009 541 patients were included in this retrospective study. RESULTS: Among the 541 cases 98 pathologies were found. These included 51 choledocholithiasis, 20 accessory bile ducts and 13 abnormal cystic ducts. In 29 of the 51 cases of choledocholithiasis a therapeutic splitting was performed only because of the MRCP. In 22 cases the diagnosis was also possible because of the basic diagnostic procedures like ultrasound, laboratory tests and clinical appearance. So the diagnostic aimprovement due to the MRCP is 5.3 %. Four of the 20 accessory bile ducts and 6 of the abnormal cystic ducts were found during the subsequent operation. The sensitivity concerning the anatomic variants is very low (38.5 % concerning the accessory bile ducts and 50 % for the abnormal cystic ducts). But the sensitivity in detecting a choledocholithiasis is very high (94.7 %). There was no evidence in our study that MRCP prevented any complications. The operation method was not changed in any case because of the MRCP result. CONCLUSION: A routinely performed preoperative MRCP cannot be recommended.

[The potential for training of proprioceptive and coordinative parameters in patients with chronic ankle instability]. / Die Trainierbarkeit von propriozeptiven und koordinativen Parametern bei der chronisch-funktionellen Sprunggelenkinstabilität.

AIM: This study was aimed at assessing the outcome of physical therapy based on both subjective patient's satisfaction and objective measurement of peroneal reaction time in patients with chronic ankle instability. METHOD: 25 patients with chronic ankle instability based on functional deficits were included. Physical therapy consisted in a 6 weeklong program with muscle strengthening and coordination exercises for one hour, three times a week. Before starting physical therapy as well as two weeks after finishing the program, patients underwent both a clinical exam as well as measurement of their peroneal reaction time. RESULTS: Following physical therapy peroneal reaction time of the long (p = 0.0001) and short (p = 0.0003) peroneal muscles significantly decreased. Prior to physical therapy the Kitaoka score was calculated to be 72.2 (+/- 18.7), the post treatment value was 93.3 (+/- 11.7) with a p-value of < 0.001. As for subjective patient's assessment on a scale of 1-10 with 1 being the least and 10 the most satisfied with therapeutical outcome, patients gave an average post treatment score of 8.3 (+/- 1.9). CONCLUSION: Measurement of PRT can be used as a helpful diagnostic parameter, as a parameter for quality control and for verification of therapy results. Specific physiotherapy leads to good clinical results and increased PRT.

Anatomical repair of lateral ligaments in patients with chronic ankle instability.

In a prospective study, 19 patients with chronic ankle instability underwent clinical and radiographic reexaminations 36 months after anatomical reconstruction. In addition, dynamic pedography was conducted and peroneal reaction time measured on a tilting platform for an evaluation of functional aspects. Prior to this examination, 32 patients had been asked to fill in a questionnaire and make a detailed subjective evaluation of current discomfort, stability, flexibility and sporting abilities. Eighty-eight percent of the patients reported satisfactory results; only 3% complained of persistent instability. In 71% the ability to take part in sports had improved after surgery, and 85% of the patients reported unrestricted walking abilities. Supination ability was impaired in 5% of the patients at the follow-up. The radiographic examination showed restored ankle stability with a significant reduction of talar tilt and talar translation; a postoperative increase in signs and symptoms of arthrosis was not observed. Dynamic pedography showed a large degree of symmetry of plantar pressure distribution after surgery. There were no significant differences in peroneal reaction time in the repaired and intact ankles. The results of the study show that it is possible to restore ankle stability with anatomical reconstruction without impairing the range of movement in the ankle joint complex. Progressive osteoarthrosis can be prevented.

Reconstruction of the lateral ligaments: do the anatomical procedures restore physiologic ankle kinematics?

BACKGROUND: If conservative therapy fails, the standard treatment for chronic ankle instability is surgical reconstruction of the lateral ligaments. For the last seventy years, the tenodesis principles have been used for reconstruction. Recently however, surgical reconstructions--respecting the intact joint anatomy--have been developed, thus called "anatomical reconstruction principles". METHODS: This study focused on the investigation of the range of motion of the ankle and the subtalar joint following anatomical reconstruction surgery. Three different types of anatomical reconstruction procedures were compared: Direct ligament repair, tendon graft and carbon-fiber implant. RESULTS: All procedures restored the original range of motion of the subtalar joint, except for the plantarflexed/dorsiflexed positions. As for the talocrural joint, the tendon graft and the carbon fiber implant left a small laxity for movements of inversion/eversion and internal/external rotation. The direct repair procedure achieved a more accurate result and restored the physiologic kinematics almost completely. During each procedure the insertion points and the direction of the original ligaments were maintained. However, the different results for the procedure of direct ligament repair compared to the other two anatomical reconstruction procedures showed that this condition alone is not sufficient to perfectly restore the kinematics of the talocrural and subtalar joints. It is important to note that none of the procedures caused a restriction of the range of motion. CONCLUSIONS: The maintenance of the range of hindfoot motion decreases the risk of osteoarthritis as well as chronic pain or problems for the patient to walk on uneven surface. Therefore, we believe that standard therapy for chronic instability of the ankle should include direct surgical reconstruction of the ligaments. If this direct procedure cannot be performed because of poor quality of the ligaments an alternative anatomical reconstruction procedure should be considered.

Actin pedestal formation by enteropathogenic Escherichia coli and intracellular motility of Shigella flexneri are abolished in N-WASP-defective cells.

In mammalian cells, actin dynamics is tightly controlled through small GTPases of the Rho family, WASP/Scar proteins and the Arp2/3 complex. We employed Cre/loxP-mediated gene targeting to disrupt the ubiquitously expressed N-WASP in the mouse germline, which led to embryonic lethality. To elucidate the role of N-WASP at the cellular level, we immortalized embryonic fibroblasts and selected various N-WASP-defective cell lines. These fibroblasts showed no apparent morphological alterations and were highly responsive to the induction of filopodia, but failed to support the motility of Shigella flexneri. In addition, enteropathogenic Escherichia coli were incapable of inducing the formation of actin pedestals in N-WASP-defective cells. Our results prove the essential role of this protein for actin cytoskeletal changes induced by these bacterial pathogens in vivo and in addition show for the first time that N-WASP is dispensable for filopodia formation.

Scar/WAVE is localised at the tips of protruding lamellipodia in living cells.

Cell motility entails the extension of cytoplasmic processes, termed lamellipodia and filopodia. Extension is driven by actin polymerisation at the tips of these processes via molecular complexes that remain to be characterised. We show here that a green fluorescent protein (GFP) fusion of the Wiskott-Aldrich syndrome protein family member Scar1/WAVE1 is specifically recruited to the tips of lamellipodia in living B16F1 melanoma cells. Scar1-GFP was recruited only to protruding lamellipodia and was absent from filopodia. The localisation of Scar was facilitated by the finding that the formerly described inhibition of lamellipodia formation by ectopical expression of Scar, could be overcome by the treatment of cells with aluminium fluoride. These findings show that Scar is strategically located at sites of actin polymerisation specifically engaged in the protrusion of lamellipodia.

[Peroneal reaction time: study of a normal sample]. / Die peroneale Reaktionszeit: Untersuchung in einem Normalkollektiv.

Chronic functional instability is a residual problem after acute ankle sprain. Reasons may be weak ligaments and/or a deficit in the proprioceptive system. Studies have shown that peroneal reaction time (PRT) can be used to quantify proprioceptive performance. To test the influence of anthropometric data on PRT, an experimental study with 120 healthy volunteers was performed. Surface electrodes recorded the activity of the peroneal muscles after a sudden inversion on a tilting platform. It was found that PRT is not influenced by extrinsic or anthropometric data. Furthermore, the results prove a significant slackening in PRT with increasing age. Therefore, the patient's age must to be considered in judging the PRT.

Reliability of peroneal reaction time measurements.

OBJECTIVE: The purpose of this study was to demonstrate the reliability of reaction time-measurements on a tilting platform under consideration of various influencing factors. DESIGN: The peroneal reaction time of 30 healthy subjects was examined in an experimental study. BACKGROUND: Peroneal reaction time measurements have been used to objectively evaluate functional instability of the ankle joint, but the reliability of the method has not been proven yet. METHODS: The reaction time after sudden inversion of the ankle were determined by surface EMG. RESULTS: The median latency of the peroneus brevis was 66 ms and that of the peroneus longus was 63 ms. No differences between male and female subjects and between left and right legs could be found. An increase of reaction time was caused by neuromuscular fatigue (P=0.033, for both the peroneus brevis and the peroneus longus). A decrease in reaction time resulted if the foot was held in 15 degrees of plantar flexion (P=0.0004 for the peroneus brevis, P=0.002 for the peroneus longus). The reliability was examined by circadian and by day-to-day measurements. The coefficient of correlation (Spearman's rho) between the peroneus brevis and days 1-5 was 0.67 (P=0.177) and for the peroneus longus 0. 00 (P0.999). The same results were obtained after the circadian measurements. CONCLUSION: Determination of peroneal reaction time was proven as a reliable measurement method. RELEVANCE: Reliability and validity are basic preconditions of a test to become accepted as a clinical measurement method. This paper demonstrates the reliability of measuring the peroneal reaction time. Thus, assuming validity, the peroneal reaction time measurement is justified as a clinical test.

[Predictive value of different injured components in ankle fractures]. / Die prognostische Bedeutung verletzter Anteile bei Sprunggelenkfrakturen.

Injuries of the medial ankle side or the posterior tibial margin do not necessarily predict a negative outcome in ankle fractures, as shown in this comprehensive retrospective study on 342 consecutive patients. A negative predictive value results from the combination of different injured ankle components. Clinical and radiological results correlate well with each other and with the severity of the fracture. They deteriorate according to the number of injured ankle components. Thickening of the soft tissues most often results from complex injuries. It leads to a decrease in range of motion and therefore determines the clinical outcome. Eighty-nine percent of the patients with a personal follow-up and 94 % of those with a written investigation had good to very good results, which represent the upper range of other presentations. This can be achieved by a subtle surgical technique with exact anatomic reduction including primary treatment of at least the severe injuries within the first few hours after trauma. Complications occurred in 9 % of cases, which coincides with the findings of other authors. Especially elderly and obese patients are at higher risk.

[The significance of intracompartmental pressure values for the diagnosis of chronic functional compartment syndrome. A meta-analysis of research studies of pressures in anterior M. tibialis during exercise stress]. / Die Bedeutung intrakompartimenteller Druckwerte für die Diagnose des chronisch-funktionellen Kompartmentsyndroms. Eine Metaanalyse von Studien des Druckverlaufs im M. tibialis anterior während einer Ubungsbelastung.

INTRODUCTION: The chronic exertional compartment syndrome of the musculus tibialis anterior is thought to be responsible for a major part of complaints of the lower leg among active sportsmen. There is an important role of tissue pressure measurement in diagnosing chronic anterior compartment syndrome during muscular activity. However, there is a controversial debate about the relevant parameters. METHODS: Metaanalysis of all the 21 studies (1979-1998) measuring intracompartmental pressures during muscular activity. Parameters of analysis: type of exercise, catheter technique, recommendations of diagnostic criteria. RESULTS: Analysis of literature shows that there has been no standardisation concerning the type of muscular exertion (isometrics for 5-10 min, exercise on the treadmill between 3.2 and 12 km/h). In 8 of the 21 studies the results have been attained through the unsuitable Wick-catheter-technique. In the overall view none of the suggested criterions for diagnosis is taken up by other teams. There are considerable variations up to 500% regarding the recommended parameters. CONCLUSIONS: From all studies no uniform recommendation for parameters of diagnostic relevance can be derived. On this background it should be demanded that future research is conducted by a uniform regimen for examination and modern technique of measuring with a high temporal resolution. Under these standardised conditions the investigated parameters of the intracompartmental pressure curve should be reconsidered once more regarding diagnostic predictability by calculations of specifity and sensitivity.

[Dynamic gait analysis. Means for quality assurance after surgically treated ankle joint fractures]. / Dynamische Ganganalyse. Mittel zur Qualitätssicherung nach operativ versorgten Sprunggelenkfrakturen.

Forty-nine patients (mean age, 54 years) admitted for displaced ankle fractures were observed retrospectively to determine by clinical examination and measurement of plantar pressure distribution whether successful surgical treatment of ankle fractures had led to gait symmetry. The mean followup was 36 months (range, 19-54 months). The deviation in gait was quantified using peak pressure. Using a clinical score, most of the patients had satisfactory results. The plantar pressure distribution showed significant load asymmetries of patients with satisfactory results and those with non-satisfactory results. Dynamic gait analysis allows quantification of gait asymmetry and clinically non-visible gait disorder.

12-year outcome after modified Watson-Jones tenodesis for ankle instability.

In a retrospective study, the long term outcome of the modified Watson-Jones tenodesis according to Lemberger and Kramer was determined using a questionnaire, clinical examination, radiographic data, including stress views, measurement of plantar pressure distribution, and peroneal reaction times on a tilt board. Twenty-five male patients (mean age, 34 years) with a mean followup of 12 years from surgery were available for examination. Eighteen patients (72%) were classified clinically as having excellent or good results. The higher presence of osteophytes in the surgically treated ankle in comparison with the opposite side indicated the progression of arthrosis with time, but this finding could not be related to the reconstruction method. Anterior drawer and talar tilt were reduced significantly in comparison with the preoperative stress radiographs. No differences in plantar pressure distribution were seen between the patients' surgically treated and nonsurgically treated feet. The peroneal reaction times of the peroneus brevis and peroneus longus muscles were significantly shorter in the surgically treated foot compared with the opposite side. It was concluded that the modified Watson-Jones tenodesis effectively corrected lateral ankle instability with no clinical deterioration with time and no influence on gait.

A protease from the marine sponge Callyspongia schulzi.

Aqueous extracts of 25 marine sponge species (from coral reefs of Papua New Guinea) were screened for proteolytic activity. Only one sponge, Callyspongia schulzi, showed remarkable activity. A protease hydrolyzing casein as well as the synthetic substrate alpha-N-benzoyl-L-arginine ethyl ester was isolated from the sponge extract by gel filtration, ion-exchange and HPLC absorption chromatography. The enzyme was homogenous in SDS-PAGE exhibiting an apparent molecular weight of 80 kDa. Its pH optimum was in the range of 9-11, it was remarkably heat-stable and was not inhibited by phenylmethane sulfonylfluoride, soybean trypsin inhibitor, aprotinin or alpha1-antitrypsin, but by EDTA and 1,10-phenanthroline suggesting properties of a metalloprotease. The protease hydrolyzed the oxidized insulin B-chain between Arg22-Gly23 and Lys29-Ala30, similar to trypsin.