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Biomedical subjects

E Wiedemann

Publications and source records attributed to E Wiedemann.

At least 19 recordsLinked to original sources
PubMed2006

[Shoulder prostheses].

The design of shoulder prostheses has been developed through four generations which mirror adaptation to our increasing knowledge of the biomechanics of the shoulder joint. Modern shoulder prostheses are adapted to the size, inclination, posterior offset, and retrotorsion of the shoulder. The main reasons for implantation of a shoulder prosthesis are primary osteoarthritis, posttraumatic and rheumatoid arthritis, avascular necrosis, instability arthritis and cuff defect arthropathy. Typical implants are cup prostheses for surface replacement, anatomical stem prostheses, and reverse prostheses. Total prostheses are functionally better as soon as the arthritis involves the glenoid, whereas hemiprostheses should be preferred as long as the glenoid is intact. The stem is mostly cemented, whereas in younger patients with good bone quality a cementless stem may be used. Cemented glenoids may be considered as standard.

Arthritis, Rheumatoid↗
PubMed2004

[Fractures of the scapula].

Two thirds of the fractures of the scapula refer to its body, one third to its neck, and one forth to the glenoid. They are indicative of high-energy blunt trauma. Traffic injuries are their main cause. Associated ipsilateral upper torso injuries are common and have to be considered!Scapular fractures may be classified as being extra- or intraarticular. Extraarticular fractures concern the scapular body, its processes, or the scapular neck. A fracture of the surgical neck of the scapula accompanied by an injury to the coracoclavicular connection is regarded as a "floating shoulder". In this case the broken suspension of the glenoid has to be reconstructed. Most intraarticular fractures are of the Bankart variety, where a shoulder dislocation spreads an oblique fragment of the glenoid. They should be treated by internal fixation, if the size of the fragment is bigger than 16 mm. Where surgery is advisable, an appropriate approach has to be chosen depending on the type of the fracture. The anterior approach of Neer and the dorsolateral approach of Brodsky are very suitable. As a basic principle dislocated or unstable fractures of the scapular processes and of the glenoid should be treated by internal fixation, since their functional result may be less than fair if they are treated conservatively. Most other fractures heal uneventful under a conservative regimen.

Accidents, Traffic↗
PubMed2003

[Secondary decompression trepanation in progressive post-traumatic brain edema after primary decompressive craniotomy].

Besides evacuation of epidural or subdural hematoma, early decompressive craniectomy with duraplasty has to be performed in the neurotraumatological care of patients with moderate [Glasgow Coma Scale (GCS) score 9-12 points] or severe traumatic brain injury (TBI; GCS score </=8 points) and threatening herniation. The efficacy of secondary decompressive craniectomy and duraplasty after primary trepanation is under debate due to missing evidence of improved outcome. The objectives of this study were to register the incidence of increasing brain edema after isolated TBI and primary craniectomy, to identify possible decision criteria for secondary decompressive trepanation, and to evaluate the neurological performance 6 months after discharge with the Glasgow Outcome Score (GOS). Of 131 patients who suffered from isolated TBI and had to be primarily operated between January 1997 and December 2001, 58 (male:female = 48:10; median age of 50.9 years) were included in this analysis. In 11 patients (male:female = 9:2; median age of 40.0 years) a secondary unilateral extensive or contralateral decompressive craniectomy had to be performed in the clinical course. Four of the 11 patients (36.4%) did not survive TBI; they died at a median of 1 day after revision or 6 days after TBI, respectively. In the group of secondary decompressive craniectomy we recorded admission (80.0 min after TBI) 35 min later ( p=0.009) than in the group of primary trepanation. Prehospital otorrhagia was observed more frequently ( p=0.036). In univariate analysis, arterial hypotension ( p=0.018) and otorrhagia at admission ( p=0.035), intracranial pressure (ICP) immediately after primary operation ( p=0.024), and decrease of maximal postoperative cerebral perfusion pressure (CPP; p=0.031) below the median cutoff value of 70 mmHg correlated with the event of secondary decompression craniectomy. Multivariate analysis identified decreased maximal CPP after primary trepanation as the only independent prognostic parameter (score 10.496; df=1; p=0.043) for the necessity of secondary trepanation and unfavorable GOS 6 months after discharge. In patients with isolated moderate or severe TBI, prehospital arterial hypotension as well as otorrhagia negatively influenced the mortality and morbidity. Therefore, early adjustment of arterial hypotension and the rapid transport into a neurotraumatological center are to be required for prehospital management of TBI patients. The decrease of maximal CPP below 70 mmHg despite administration of catecholamines representing the only independent prognostic parameter during monitoring in the intensive care unit seems to indicate the necessity of an operative revision as well as an unfavorable GOS 6 months after discharge.

Adult↗
PubMed2003

Microcirculation associated with degenerative rotator cuff lesions. In vivo assessment with orthogonal polarization spectral imaging during arthroscopy of the shoulder.

BACKGROUND: Diminished vascular supply is associated with degenerative rotator cuff lesions. Orthogonal polarization spectral imaging allows noninvasive assessment of microcirculation without application of fluorescent contrast medium. The aim of our study was to visualize and quantify in vivo the microcirculation of the rotator cuff during arthroscopic surgery and to compare the results with the number of microvessels identified in vitro by immunostaining of biopsy specimens taken from the scanned areas. METHODS: Eleven patients with clinical signs of a degenerative rotator cuff lesion were studied. Prior to arthroscopic subacromial decompression, the superficial part of the supraspinatus tendon at the edge of the lesion as well as the unaffected tendon insertion was examined. Microvascular parameters established for the description of tissue perfusion with use of conventional intravital fluorescence microscopy (functional capillary density and capillary diameter) were assessed in vivo. Biopsy specimens were taken from the scanned areas, and the microvessels were localized by immunostaining for the endothelial surface marker CD31. RESULTS: In the region of the unaffected tendon insertion, the mean baseline functional capillary density (and standard deviation) was 106 +/- 13 cm/cm(2) and the mean capillary diameter was 10 +/- 0.7 microm. In contrast, at the edge of the lesion, the functional capillary density was significantly reduced to 20 +/- 14 cm/cm(2), whereas the diameter of the vessels that were present did not differ. The total number of vessels stained in vitro was also significantly reduced at the edge of the lesion compared with the number of vessels in the tendon insertion zone. CONCLUSIONS: Quantitative in vivo analysis of human microcirculation during arthroscopy demonstrated that the functional capillary density at the edge of a degenerative rotator cuff lesion was significantly reduced compared with that in the control tissue. The capacity to assess microcirculatory flow in vivo may help to identify specific repair strategies based on knowledge of individual perfusion patterns.

Arthroscopy↗
PubMed2002

Rationales of arthroscopic shoulder stabilization.

Arthroscopic reconstruction of glenohumeral instability has become more common during the past decade. Compared with open reconstruction, which is still the gold standard in the treatment of shoulder instability, arthroscopic techniques allow for improved diagnosis of numerous intraarticular findings. This review presents an appropriate system for the arthroscopic classification of most pathological findings in patients with anterior shoulder instability. Based on the presented classification, a rationale for arthroscopic reconstruction under special conditions is given. Several operative techniques and implants are discussed and their use in certain circumstances analyzed. Special emphasis is targeted on techniques of realizing sufficient capsular shift or plication. Arthroscopic procedures remain technically demanding and require skills to address the great variety of possible situations. On the other hand, arthroscopic techniques in shoulder reconstruction benefit patients by avoiding the morbidity of open surgery. However, the surgeon must be prepared to address numerous conditions beyond a mere Bankart lesion, especially those involving capsular laxity, rotator interval lesions, and SLAP (superior labrum lesions from anterior to posterior) lesions. Nowadays, considering all the new technical possibilities of arthroscopic shoulder reconstruction including capsular shift procedures, most cases of anterior shoulder instability are suitable for arthroscopic reconstruction. Further studies are necessary to validate the continued efficacy of arthroscopic stabilization.

Arthroscopy↗
PubMed2002

Rapid identification of high-risk patients after minor head trauma (MHT) by assessment of S-100B: ascertainment of a cut-off level.

BACKGROUND: Elevated blood S-100B levels were described by several authors for reliable identification of patients with intracerebral complications after minor head trauma (MHT). Yet, test systems used so far require more than 3 hours processing period which is too long to enable immediate further diagnostic or therapeutic consequences. Therefore we validate a new rapid test version for S-100B measurements and established an effective cut-off level to identify high risk patients. METHODS: 104 patients suffering from MHT were enrolled. After taking blood samples S-100B values were achieved by the long-term and rapid (40 min processing time) test system, respectively, and compared using linear regression analysis. For determination of an effective cut-off level receiver operating characteristics curves were calculated in accordance with cranial computed tomography findings. RESULTS: S-100B concentrations correlated significantly using both test systems. A cut-off level of 0.18ng/ml was calculated in plasma samples. CONCLUSIONS: S-100B concentrations above the cut-off level measured within 40 min after blood sampling allows safe identification and immediate treatment of intracerebral lesions (e.g. epidural and subdural hematoma, subarachnoid hemorrhage, diffuse brain edema etc.) in MHT patients.

Blood Chemical Analysis↗
PubMed2002

[Fixed and functional decentering of the head of the humerus in patients with omarthrosis].

AIM: To determine whether in patients with specific types of osteoarthritis of the shoulder not only a fixed but also a functional decentering of the humeral head exist. METHOD: The shoulder joints of 10 healthy volunteers and of 16 patients with osteoarthritis of the shoulder were examined in various arm-positions, using an open MR scanner. After segmentation, 3D reconstruction of the scapula and humerus were performed and the position of the midpoint of the humeral head calculated relative to the center of mass of the glenoid cavity. RESULTS: At 30 degrees of abduction, 4 of 16 patients demonstrated a fixed posterior (12.9 +/- 2.8 mm) position and 8 (all patients with cuff-arthropathy) a fixed superior (6.6 +/- 2.6 mm) position of the humeral head. At 90 degrees of abduction the patients showed a significant (p < 0.001) combined decentering in the superior and posterior direction as compared to the healthy shoulders (functional decentering). CONCLUSIONS: This study demonstrates, that in most of the patients with osteoarthritis of the shoulder, a significant functional decentering occurred during abduction and external rotation, even if they showed no fixed decentering of the humeral head at 30 degrees of abduction.

Aged↗
PubMed2001

S-100b, sE-selectin, and sP-selectin for evaluation of hypoxic brain damage in patients after cardiopulmonary resuscitation: pilot study.

S-100b is thought to be a screening marker of hypoxic brain damage in patients with cardiac arrest. However, the time-dependent occurrence and relevance of increased S-100b serum levels in out-of-hospital patients with cardiopulmonary resuscitation (CPR) is still discussed. The purpose of our study was to evaluate the diagnostic utility of S-100b measurements in comparison to that of adhesion molecules sE-selectin and sP-selectin in patients with CPR. Sixteen out-of-hospital patients (median age 69.6 years; range 59.2-82.2 years) suffering from cardiac arrest due to ventricular fibrillation, asystole, or electromechanical dissociation were recruited prospectively. Blood samples were drawn on scene after the return of spontaneous circulation (ROSC) and 12 hours after successful CPR. The reference group consisted of 10 patients with isolated severe head trauma (SHT) (Glasgow Coma Score </ or =8), and the control group comprised 20 healthy volunteers. Serum concentrations of S-100b, determined by immunoluminometric assay, were compared with serum levels of sE-selectin and sP-selectin measured by an enzyme-linked immunosorbent assay and correlated with the patients' survival. In the CPR group, S-100b serum levels (2.37 ng/ml; 1.37-4.09 ng/ml) at study entry (11.6 minutes after arriving on scene) did not significantly differ from those of SHT patients (2.88 ng/ml; 1.78-8.81 ng/ml). Both groups showed significant differences from the healthy controls (0.04 ng/ml; 0.01-0.82 ng/ml). At 12 hours after CPR the serum levels had decreased to 0.41 ng/ml (0.24-0.51 ng/ml) but continued to be significantly elevated compared to that of the control group. sE-selectin values in serum increased from 56.00 ng/ml (38.50-85.50 ng/ml) on scene to 79.00 ng/ml (52.00-127.00 ng/ml) after 12 hours (p < 0.05). The first measurements differed significantly from serum levels of the control group (22.50 ng/ml; 14.00-34.00 ng/ml) and from those of the SHT group (45.00 ng/ml; 39.00-63.75 ng/ml). At 12 hours after study entry the sE-selectin values were not significantly different from those of the SHT group (51.50 ng/ml; 39.00-95.88 ng/ml). sP-selectin serum levels increased slightly from 199.50 ng/ml (184.25-227.25 ng/ml) to 247.00 ng/ml (206.50-354.75 ng/ml). First and second measurements did not reveal any significant differences in either the SHT group or the healthy controls. When correlated with survival, S-100b measurements exhibited constantly high serum levels for patients, decreasing within the first 24 hours, whereas they decreased significantly in patients with longer survival. sP-selectin values on scene slightly increased in cases of survivals less than 24 hours after CPR. sE-selectin serum levels always remained within normal levels and revealed no significance later on. In contrast to the endothelium-derived adhesion molecules sE-selectin and sP-selectin, comparison of measurements of specific neuroprotein S-100b early after cardiac arrest and 12 hours later seem to provide an indication of the severity of hypoxic brain damage and the prognosis after CPR. Further investigations are required to better understand the CPR-related mechanisms of blood-brain barrier damage.

Aged↗
PubMed2001

Evaluation of S-100b as a specific marker for neuronal damage due to minor head trauma.

Management of patients with minor head trauma (MHT) continues to be debated in the literature. Measurement of S-100b in serum has been introduced into the discussion as an additional screening tool for intracerebral injuries because routine cranial computed tomography (CCT) of a large number of patients causes logistic difficulties, and the neurologic examination is often impaired by a high frequency of coincidental intoxication. The aim of our study was to determine the diagnostic value of measuring S-100b in the serum of MHT patients to identify risk groups. Additional validity should be aquired by a comparison with plasma levels of polymorphonuclear neutrophil (PMN) elastase an established general trauma marker. A series of 52 patients with MHT were included in the prospective study. At admission the patients underwent a routine CCT scan to detect intracerebral lesions, and blood samples were drawn to investigate circulating levels of S-100b and PMN elastase. For comparison, data for a positive control group of 10 severe head trauma patients (initial Glasgow Coma Scale score < 8) and for a negative control group with 20 healthy volunteers were obtained. The interval between MHT and admission to our hospital was 73.4 +/- 47.0 minutes. The initial S-100b serum levels of MHT patients were 0.470 +/- 0.099 ng/ml, those of the positive control group were 7.16 +/- 3.77 ng/ml, and those of the negative control group were 0.05 +/- 0.01 ng/ml. Relevant pathologic CCT scans were detected in 28.8% of MHT patients; one patient of that group was subjected to immediate surgical intervention (1.9%). At a cut-off point of 0.1 ng/ml, the sensitivity of positive S-100b levels reached 100% and the specificity 40.5%. Plasma levels of PMN elastase reached 60.52 +/- 10.75 ng/ml in the MHT group, 66.4 +/- 14.92 ng/ml in the severely head-injured group, and 23.26 +/- 1.53 ng/ml in the negative control group. Serum levels of S-100b seem to be a highly sensitive but not very specific marker for isolated neurotrauma. Measurement of this parameter may be helpful as an additional screening tool to identify high risk groups in the cohort of MHT patients.

Autoantigens↗
PubMed2001

Early cellular brain damage and systemic inflammatory response after cardiopulmonary resuscitation or isolated severe head trauma: a comparative pilot study on common pathomechanisms.

Severe neurological deficits are common characteristics of patients surviving cardiopulmonary resuscitation (CPR) or isolated severe head trauma (SHT). For comparative evaluation of underlying pathomechanisms, 22 patients with out-of-hospital cardiac arrest and successful CPR as well as 10 patients with SHT were included in our prospective study. Circulating S-100B was determined as an indicator of cellular brain damage. Interleukin-8 (IL-8), soluble E-selectin (sE-selectin) and polymorphonuclear (PMN-) elastase were measured as markers of systemic inflammation following whole body ischaemia and reperfusion injury. Venous blood samples were drawn on scene (median time 11.0 min after starting basic life support) and in the intensive care unit (median time 12.5 h thereafter) in CPR patients and at admission to hospital (median time 43.8 min after trauma) and approx. 12 h later in SHT patients. Biochemical parameters in these samples were compared with specimens taken from 20 healthy volunteers. Initial median S-100B levels of the CPR and SHT patients were both significantly increased compared with the controls. Twelve hours later, significant falls in S-100B revealed no differences between the two patient groups, but did not reach control values. Median IL-8 and sE-selectin levels entry to the study were elevated in both patient groups compared with controls and showed further rises within the following 12 h. Finally, increased initial median levels of PMN-elastase revealed significant differences between the patient groups and between patients and controls. Twelve hours later, median PMN-elastase values were equally elevated in the CPR and SHT subjects. Our preliminary data suggest similar pathomechanisms occurring after both CPR and SHT. Both clinical entities seem to be associated with early transient cellular brain damage as shown by prolonged rapidly increasing and subsequent fall in S-100B serum levels. In contrast, the prolonged elevation of circulating IL-8, sE-selectin and PMN-elastase may indicate a very similar systemic inflammatory response by endothelial cells and neutrophils initiated by ischaemia and reperfusion injury in both conditions. Further studies should be carried out to determine the cause and the prognostic value of these biochemical parameters in relation to long-term neurological outcome.

Aged↗
PubMed2001

Three-dimensional analysis of shoulder girdle and supraspinatus motion patterns in patients with impingement syndrome.

Alterations of the shoulder girdle motion have been suggested to be associated with shoulder disorders. The objective of this study was to perform a three-dimensional (3D) motion analysis of the supraspinatus muscle and shoulder girdle in patients with different stages of impingement syndrome. 20 patients with unilateral impingement and 14 normal controls were investigated at 30 degrees, 90 degrees, and 120 degrees of abduction with and without abducting muscle activity. The spatial relationship between the shoulder girdle elements and the supraspinatus was quantified from open MRI data. No significant alterations in glenoid rotation were observed between the patients and asymptomatic volunteers. However, while in the healthy volunteers the values showed a normal distribution (28.5+/-3.6 degrees at 90 degrees abduction with muscle activity), the patients (30.5 degrees+/-9.7 degrees) contained a subset of five individuals with an obvious increase in glenoid rotation angle (>40 degrees) compared with controls (>2.5 standard deviations higher than the mean) and with the healthy contralateral side. These five patients also displayed alterations in the scapulo-humeral rhythm and supraspinatus motion, but not in clavicular position. The study shows that only a specific subset of patients with impingement syndrome demonstrates complex changes in shoulder girdle and supraspinatus motion patterns, suggesting that this subset may benefit from an alternative type of treatment.

Adult↗
PubMed2001

Elevated serum levels of S-100B reflect the extent of brain injury in alcohol intoxicated patients after mild head trauma.

Elevated systemic levels of S-100B are proposed as a potential indicator of brain damage in identifying high-risk patients after mild head trauma (MHT). Although incidence of alcohol intoxication is high in these patients, the influence of alcohol intoxication on S-100B levels is unclear. Therefore, the aim of our study was to investigate serum concentrations of S-100B in intoxicated (group 1) and sober (group 2) patients after MHT in comparison with those of mild (group 3) or severely intoxicated (group 4) individuals without trauma. S-100B was significantly increased in MHT patients exhibiting posttraumatic lesions in initial cranial computed tomography scan. Alcohol intoxication did not elevate S-100B levels in group 3 or 4 subjects. Our data indicate for the first time that alcohol intoxication does not influence the diagnostic value of S-100B measurements in patients after MHT.

Alcohol Drinking↗
PubMed2000

Influence of alcohol exposure on S-100b serum levels.

Recent assessment of the glia cell-derived neuroprotein S-100b in serum has been considered as a screening method for possibly occult brain injury in patients with minor head trauma (MHT). Since MHT is associated with alcohol intoxication in up to 50% of patients requiring emergency treatment, the blood-brain barrier (BBB) as well as neuronal cell integrity may be also affected by alcohol abuse. So far, however, no valid data are available on the release of S-100b after alcohol exposure. Thus, the aim of our study was to investigate S-100b serum levels in a controlled alcohol exposure paradigm. 22 healthy volunteers were included in the study, blood samples were drawn prior to and about 90 minutes after drinking. The amount of alcohol was adjusted to the body weight. A mean of 66.7 +/- 14.81 g was consumed giving raise to a blood alcohol concentration of 0.827 +/- 0.158@1000. S-100b serum levels assayed by a luminescence immunoassay were compared with those of MHT patients. The still preliminary results suggest no increase of the serum S-100b levels (0.0509 +/- 0.048 ng/ml versus 0.0422 +/- 0.044 ng/ml) after moderate alcohol consumption. In contrast, MHT patients with alcohol intoxication (1.6 +/- 0.77@1000) revealed a significant up to 10fold elevation of S-100b serum levels. Because of the much higher blood alcohol concentration in the MHT patients compared to the control collective, a potential relationship between excessive alcohol consumption and the release of S-100b in minor head trauma can still not be excluded. Further investigations on this topic are in progress.

Adult↗
PubMed2000

S-100b as a screening marker of the severity of minor head trauma (MHT)--a pilot study.

Due to its neural tissue specificity S-100b is considered as a screening marker of cerebral injury in head trauma patients. However, the occurrence and relevance of an increased S-100b serum level in minor head trauma (MHT) is still debated. Therefore, the purpose of our study was to evaluate the diagnostic utility of S-100b measurements in a level I trauma center emergency room (ER). Eighty patients presenting with clinical symptoms of MHT (GCS score of 13-15, transitory loss of consciousness, amnesia, nausea) were prospectively recruited. Blood samples were drawn at 0 h, 6 h and 24 h after admission, and a cerebral computed tomography (CT) was performed. The reference group consisted of 10 patients with severe head injury (GCS score < 8), the control group of 20 healthy volunteers. Concentrations of S-100b in serum were determined by an immunoluminometric assay. The results were compared with the plasma levels of polymorphonuclear (PMN) elastase as an established general trauma marker. In the MHT group, the S-100b serum level revealed 1.26 +/- 0.57 ng/ml at study entry (73.46 +/- 47.53 min after trauma). In comparison, the S-100b concentration was significantly elevated in patients with severe head trauma (5.26 +/- 1.65 ng/ml, p = 0.009), but no significant difference became evident in relation to the control group (0.05 +/- 0.01 ng/ml). Starting values of PMN elastase in plasma amounted to 66.40 +/- 14.92 ng/ml in severe trauma, and to 60.52 +/- 10.75 ng/ml in MHT showing significant differences only in relation to the control group (23.36 +/- 1.53 ng/ml). When correlated with the severity of the later clinical course, the first S-100b measurements exhibited steadily increasing values as demonstrated in MHT outpatients (0.29 +/- 0.11 ng/ml), MHT in-hospital patients (0.70 +/- 0.19 ng/ml) and MHT intensive care unit patients (5.03 +/- 3.18 ng/ml). PMN elastase levels revealed no significant differences concerning the three MHT subgroups. Thus, in contrast to the general trauma marker PMN elastase, assessment of the specific neuroprotein S-100b early after traumatic insult appears to be a promising laboratory marker for the prognosis of the severity of brain injury in MHT patients. Nevertheless, further investigations are required to better understand its predictive value.

Biomarkers↗
PubMed2000

[Recommendations for diagnosis and expert assessment of traumatic rotator cuff lesions].

Traumatic rotator cuff lesions are a very rare condition. However, this article represents a comprehensive survey according to current knowledge on anatomy, biomechanics, and pathogenesis of rotator cuff pathology. Because of the relatively high prevalence of degenerative changes with increasing age, including partial and complete rotator cuff tears, it may be difficult to demonstrate the causality of an acute traumatic rotator cuff tear. Therefore, a catalogue of potential adequate and inadequate trauma mechanisms is proposed. Emphasis is also placed on posttraumatic diagnostic steps following persistent rotator cuff deficient shoulder function (e.g., ultrasound, MRI). From a legal aspect (e.g., private accident insurance, workers compensation claim), different minor and major criteria are defined, which could help experts to judge the causality of posttraumatic rotator cuff deficiency. These criteria mainly refer to distinct details concerning patients' history, trauma mechanism, primary clinical appearance, and diagnostic findings.

Diagnosis, Differential↗