Biomedical subjects

M Loew

Publications and source records attributed to M Loew.

At least 19 recordsLinked to original sources

PubMed2002

[Etiology of rotator-cuff-tears and consequences for legal assessment].

Traumatic or degenerative etiology of rotator-cuff-tears is a matter of controversial discussion in legal proceedings. This article presents a review on the literature about current knowledge of anatomy, biomechanics and pathogenesis of rotator-cuff pathology. According to this a catalogue of potentially adequate and inadequate trauma mechanisms is proposed. Furthermore clinical history and examination as well as sonographic and radiologic findings and intraoperative pathology may help to distinguish between traumatic and degenerative changes of rotator-cuff lesions. The keypoints for and against traumatic etiology of rotator-cuff-tears are mentioned that could help the expert in the preparation of an adequate expert opinion.

Diagnosis, Differential↗

PubMed2001

Chondrocyte expressed protein-68 (CEP-68), a novel human marker gene for cultured chondrocytes.

In the search for new marker genes suitable to distinguish chondrocytes from osteoblasts and mesenchymal stem cells in culture, we have identified and characterized a novel gene called chondrocyte expressed protein-68 (CEP-68), harbouring an N-terminal leader peptide and an epidermal growth factor-like calcium-binding domain. CEP-68 defines a new family of proteins and complements collagen type II as a new marker for stem-cell-based chondrogenic tissue engineering.

Amino Acid Sequence↗

PubMed2001

Analysis of the first heart sound using the matching pursuit method.

It is acknowledged that the first heart sound S1 consists of two major, high-frequency components M1 and T1, corresponding, respectively, to the vibrations of the mitral and tricuspid valves and their surrounding tissues following valve closure in early systole. In this study, the matching pursuit (MP) method was used to decompose S1 into a series of time-frequency atoms. M1 and T1 were separated from the parameterised atoms of S1. The first two dominant frequencies of M1 were identified and used as features of a linear classifier to diagnose mitral valve abnormality. This method was applied to two sets of S1 data recorded from 15 patients with normal, and 15 patients with abnormal, bioprosthetic mitral valves, respectively. It was found that the two features exhibit significant differences between the normal and abnormal sets (p< 0.001). Using these two features, a correct classification of 93% was obtained. In addition, when the Wigner distribution of S1 was calculated from the decomposed atoms and compared with a spectrogram, the MP method provided better results. The study demonstrates that the MP method may be a promising technique for heart sound analysis.

Heart Murmurs↗

PubMed2001

[Injury pattern in shoulder dislocation in the elderly patient].

PROBLEM: Recurrent shoulder dislocation is reported to be rare in older patients. While injuries of the glenoid labrum and the anterior capsule following primary dislocation in younger patients seem to determine the rate of instability, the pattern of damages in the elderly has rarely been studied. METHODS: 91 patients with an age older than 40 years with the diagnosis of primary (group A, n = 50) or recurrent (group B, n = 41) anterior shoulder dislocation were included in a prospective study. By analysis of the findings in x-rays, MRI, CT-scans and in 36 patients of diagnostic arthroscopy the pattern of intra- and periarticular pathology was evaluated. RESULTS: While the incidence of bony Bankart- and Hill-Sachs lesions was constantly spread over the age groups the pattern of soft tissue damages was different. Up to the age of 60 years lesions of the glenoid labrum were leading while in older patients the prevalence of rotator cuff tears became about 70 percent. CONCLUSIONS: The development of secondary osteoarthritis and persisting symptoms in older patients with rotator cuff tears after traumatic shoulder dislocation requires early diagnosis and appropriate treatment.

Adult↗

PubMed2001

[Kinematics and biomechanics of the elbow joint].

An attempt has been made to describe the interaction of the different joint morphologies and the ligaments of the elbow in terms of the current literature. The physics of joint kinematics and biomechanics will be discussed and used to resolve current incomplete interpretations. The elbow is a very stable functional unit due to its bony tracking and "self-stabilising" ability especially in the humeroradial joint. In reconstruction and in total joint replacement, the different radii of curvature of the various surfaces have to be respected to redevelop full joint function.

Biomechanical Phenomena↗

PubMed2001

[Contracture of the elbow joint. Etiological review and general treatment concepts].

The contracture of the elbow joint is a symptom of various local changes and systemic disorders. Appropriate therapy requires a distinct knowledge of the relevant anatomical structures as well as of the etiology and pathogenesis of the functional restriction. Systematically, intrinsic contractures coming from the synovial membrane and intra-articular structures are distinguished from extrinsic contractures involving extra-articular soft tissues. The etiology of heterotopic ossifications is still widely unknown. The classification of the contracture is defined by the by extent of the remaining range of motion. Indications for surgery in severe cases depend on the degree of pain and of functional loss. Surgical arthrolysis includes a large spectrum of possibilities ranging from endocopical procedures to prosthetic joint replacement. Complications are relatively frequent after surgery and the individual gain of function is not always predictable.

Arthroplasty, Replacement↗

PubMed2001

Osteoporosis in patients with paralysis after spinal cord injury. A cross sectional study in 46 male patients with dual-energy X-ray absorptiometry.

In a cross-sectional study, 46 male patients with paralysis after spinal cord injury (average age 32 years; injuries sustained from 1 to 26 years ago; 33 Frankel A, 13 Frankel B, C, D) were examined clinically and by dual-energy X-ray absorptiometry (DEXA). Their bone mineral density (BMD) values were compared with age-related controls and correlated to clinical parameters. BMD was reduced in the proximal femur (p < 0.05) and the distal forearm (p < 0.05), but not in the lumbar spine. Demineralisation was influenced in the proximal femur (Z-score -2.95) by immobilisation after surgical treatment. Patients suffering from complete lesions had significantly lower BMD in the lumbar spine (-1.47) compared with patients with incomplete lesions (+0.02). BMD was not significantly influenced by the level of the lesion and the ambulatory status. Long-term monitoring showed significant demineralisation in the proximal femur (r = -0.36) and the distal forearm (r = -0.4), but not in the lumbar spine (r = -0.21). By correlating BMD with clinical parameters, it can be deduced that, firstly, immobilisation after surgical treatment should be reduced to a minimum; secondly, that every effort must be expended to prevent turning an incomplete into a complete lesion; and finally, that rehabilitation treatment should be lifelong.

Absorptiometry, Photon↗

PubMed2001

Quantitative assessment of in vitro jets based on three-dimensional color Doppler reconstruction.

Three-dimensional (3-D) color Doppler imaging of flow jets was performed to investigate the effects of flow rate and orifice size on jet volumes. Flow jets were generated using a flow model to simulate mitral regurgitation. This flow model consisted of a ventricular chamber, a valvular plate and an atrial chamber. Steady flow was driven through circular orifices having diameters of 2.5, 3.5, 4.5, and 6 mm, respectively, with flow rates of 5, 10, 15, 20, and 25 mL/s to form free jets in the atrial chamber. An ATL Ultramark 9 HDI system was used to perform 3-D color Doppler imaging of the flow jets. A transesophageal probe was rotated by a stepper motor to create 3-D color Doppler images of the jets. The color jet volumes for different hemodynamic conditions were measured and then compared with the theoretical predictions. Results showed that the jet volume estimated from the 3-D color Doppler was directly proportional to the flow rate and inversely proportional to the orifice size. The estimated jet volumes correlated well (r > 0.95) with theoretical predictions. This study supports the use of color jet volume as a parameter to quantify mitral regurgitation.

Blood Flow Velocity↗

PubMed2001

[Depressive disorders in neurologic rehabilitation: therapy with paroxetine].

OBJECTIVE: Depression is a common problem in neurological rehabilitation. Although three double-blind studies have shown the efficacy of trazodone, citalopram and nortriptyline, antidepressant drug therapy of poststroke depression is not yet considered a state-of-the-art strategy. In a hospital for neurological rehabilitation we have performed an open study on the effects of the SSRI, paroxetine, in depressive disorders caused by neurological diseases. METHOD: 111 consecutive admissions were screened for depression and 9 patients were admitted to the study having a HDRS score > or = 14. RESULTS: 10-40 mg of paroxetine were well tolerated and led to a > or = 50% reduction of the HDRS score in 8/9 patients. A patient with pathological crying, but without depression, was also successfully treated with 20 mg of paroxetine. CONCLUSIONS: We conclude that the SSRI, paroxetine, is an effective and well-tolerated therapy of depressive disorders caused by various neurological diseases, including also other diagnoses than stroke.

Adult↗

PubMed2001

Long term changes of the throwing arm of former elite javelin throwers.

The aim of this study was to determine long term changes in shoulder and elbow joints of former elite javelin throwers. Twenty-one elite javelin throwers were examined at an average of 19 years after the end of their high performance phase. Mean age at examination was 50 years. Functional assessment of both shoulders was determined by the Constant-score. The shoulder of the throwing arm was examined by magnetic resonance imaging. Both elbow joints were examined clinically and radiographically. Five athletes complained about transient shoulder pain in their throwing arm affecting activities of daily living, fourteen athletes had a deficit of internal rotation of at least ten degrees. Constant-scores of throwing arms were six points lower than those of non-throwing arms (P < 0.05). Complete ruptures and partial tears of the rotator cuff were frequent. Three athletes complained about transient elbow pain in their throwing arm affecting activities of daily living; ten athletes had a deficit of extension of more than five degrees. All dominant elbows had advanced arthrotic alterations (osteophytes, sclerosis) compared to the non-dominant side. Athletes who trained with weights of more than 3 kg had a significantly higher risk of degenerative changes than athletes who did not (P < 0.01). We therefore recommend to avoid throwing training with weights of more than 3 kg.

Activities of Daily Living↗

PubMed2001

A virtual instrument for acquisition and analysis of the phonocardiogram and its internet-based application.

The objective of this study is to develop a phonocardiogram (PCG) acquisition and analysis instrument using virtual instrumentation technology and investigate its Internet-based application. The PCG instrument was developed using a Pentium 200 computer, a data acquisition board, and a two-channel custom designed bio-signal preamplifier. LabVIEW was used to create the instrument's front panels. Spectral and joint time-frequency analyses were implemented into the instrument. This instrument can be used to display the PCG and to analyze the individual heart sound and murmur for the detection of heart valve diseases. Using a test-bed, the PCG data acquisition and analysis were performed remotely over the Internet. Through the main PCG panel, an operator can control the acquisition and analysis of PCG signals. In the remote test, real-time transmission of the PCG signal over the Internet was possible. Remote operators were able to view smoothly scrolling PCG waveforms and could control all the acquisition parameters and perform spectral and time-frequency analyses on the acquired heart sound. This study demonstrated that a LabVIEW-based medical virtual instrument provides a low-cost and flexible solution for data acquisition and analysis of PCG. It also showed that the current Internet supports the transmission of real-time PCG signals. Compared with other telemedicine systems, this application transfers not only the medical data, but also the virtual instrument and its signal processing capability through the Internet.

Heart Valve Diseases↗

PubMed2001

Analytical solutions for time-resolved fluorescence lifetime imaging in a turbid medium such as tissue.

An analytical solution is developed to quantify a site-specific fluorophore lifetime perturbation that occurs, for example, when the local metabolic status is different from that of surrounding tissue. This solution may be used when fluorophores are distributed throughout a highly turbid media and the site of interest is embedded many mean scattering distances from the source and the detector. The perturbation in lifetime is differentiated from photon transit delays by random walk theory. This analytical solution requires a priori knowledge of the tissue-scattering and absorption properties at the excitation and emission wavelengths that may be obtained from concurrent time-resolved reflection measurements. Additionally, the solution has been compared with the exact, numerically solved solution. Thus the presented solution forms the basis for practical lifetime imaging in turbid media such as tissue.

Biological Phenomena↗

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↗

PubMed2000

A prospective study of pain control in the emergency department.

The most common complaint in the emergency department is pain. The management of acute pain, however, has not been well studied. This prospective study was designed to assess pain intensity and relief along with satisfaction in the emergency department. Adult patients with a primary complaint of acute pain were asked to complete a two-part questionnaire administered by a research assistant. The first part was completed on arrival and the second part on discharge from the emergency department. The respondents were not permitted to see the first part of the questionnaire while completing the second. The questionnaire used an unmarked, horizontal 10-cm visual analog scale along with short answer questions to measure pain, relief, and satisfaction. Choice of drug therapy was decided by the physician according to usual treatment methods. Fifty-seven people presented with the chief complaint of pain. Of those, 30 (53%) were treated with medications. The mean level of pain on admission for treated patients was 6.64 compared with a mean level of pain on discharge of 4.02 (P =.0001). Untreated patients had a mean admission visual analog scale score of 4.19. Compared with treated patients, this difference was statistically significant (P =.001). A mean visual analog scale score of 5.43, representing the mean amount of pain relief, was reported among treated patients. Treated patients also reported a visual analog scale score of 6.46 in overall satisfaction with pain management. The results of this study indicate that there is a significant and clinical difference in levels of pain and satisfaction between admission and discharge in these patients in the emergency department.

Adult↗

PubMed2000

[In Process Citation]

The traumatic etiology of rotator cuff lesions is a||| matter of controversial discussed in legal assessments. 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 cause of an acute traumatic rotator cuff tear. This article||| presents a review of the literature concerning current knowledge of the||| anatomy, biomechanics and pathogenesis of rotator cuff pathology. According to||| this, a catalogue of potentially adequate and inadequate trauma mechanisms is||| proposed. Another focus of this work is in the post-traumatic diagnostic steps||| following persistent rotator cuff-deficient shoulder function. X-ray,||| ultrasound, MRI and operative findings in rotator cuff tears underline the||| criteria for distinguishing between traumatic and degenerative lesions. From a||| legal point of view (e.g., private accident insurance, workers compensation||| claims), various minor and major arguments are defined, which could help the||| expert in judging the cause of post-traumatic rotator cuff||| deficiency.

Journal Article↗

PubMed2000

[Traumatic development of rotator cuff lesion. Scientific principles and consequences for expert assessment].

The traumatic etiology of rotator cuff lesions is a matter of controversial discussed in legal assessments. 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 cause of an acute traumatic rotator cuff tear. This article presents a review of the literature concerning current knowledge of the anatomy, biomechanics and pathogenesis of rotator cuff pathology. According to this, a catalogue of potentially adequate and inadequate trauma mechanisms is proposed. Another focus of this work is in the post-traumatic diagnostic steps following persistent rotator cuff-deficient shoulder function. X-ray, ultrasound, MRI and operative findings in rotator cuff tears underline the criteria for distinguishing between traumatic and degenerative lesions. From a legal point of view (e.g., private accident insurance, workers compensation claims), various minor and major arguments are defined, which could help the expert in judging the cause of post-traumatic rotator cuff deficiency.

Diagnosis, Differential↗

PubMed1999

Shock-wave therapy is effective for chronic calcifying tendinitis of the shoulder.

We report a prospective study of the effects of extracorporeal shock-wave therapy in 195 patients with chronic calcifying tendinitis. In part A 80 patients with chronic symptoms were randomly assigned to a control and three subgroups which had different treatment by low-energy and high-energy shock waves. In part B 115 patients had either one or two high-energy sessions. We recorded subjective, functional and radiological findings at six months after treatment. The results showed energy-dependent success, with relief of pain ranging from 5% in our control group up to 58% after two high-energy sessions. The Constant scores and the radiological disintegration of calcification were also dose-dependent. Shockwave therapy should be considered for chronic pain due to calcific tendinitis which is resistant to conservative treatment.

Adult↗

PubMed1998

[ECG changes after paroxetine. 3 case reports].

Selective serotonin reuptake inhibitors (SSRI) are known to exhibit far less cardiac side effects than tricyclic antidepressants. We report three cases in which the SSRI, paroxetine, induced clinically relevant ECG changes in patients with high risk profile. In two cases an increase in QTc time was observed, severe bradycardia was also observed twice.

Aged↗