Biomedical subjects

Josef Kollmitzer

Publications and source records attributed to Josef Kollmitzer.

7 recordsLinked to original sources

PubMed2003

Fourier analysis of impedance rheography for peripheral arterial occlusive disease.

This study identified those harmonics from the frequency spectrum of electrical impedance rheographic signals that discriminate between patients with and without peripheral arterial occlusive disease (PAOD). Ninety-four patients with suspected PAOD were evaluated by impedance rheography and ankle-arm blood pressure index. The leg with the lower ankle-arm index was used in the analysis and a haemodynamically relevant PAOD was assumed at an ankle-arm index lower than 0.85. The frequency spectrum of the impedance signals of the shank was calculated by means of a fast Fourier transformation algorithm. The first ten harmonics were used as independent variables in a stepwise logistic regression analysis to evaluate the dependent variable PAOD. In the regression analysis only the third harmonic was accepted ( P<0.0001). The correct classification of the patients was 90%. In conclusion, by means of Fourier analysis of impedance rheographic signals, a high accuracy in the diagnosis of PAOD can be achieved.

Adolescent↗

PubMed2002

Step aerobic vs. cycle ergometer training: effects on aerobic capacity, coordinative tasks, and pleasure in untrained adults--a randomized controlled trial.

The purpose of the study was to evaluate the impact of step aerobic (StA) and cycle ergometer training (CET) on physical performance, coordination, and pleasure, during workout. Forty untrained persons (40-70 years) were randomly assigned to either of the two regimens. Prior to and after three months of training, we investigated the participants' physical performance with a cycle ergometer test and by testing coordinative tasks (upper extremities: tapping test; lower extremities: one-leg stance). After the training period, visual analog scales were used to evaluate personal assessment (pleasure, wellbeing, team spirit, interest in prolongation of training). StA increased the relative oxygen uptake at the anaerobic threshold (RVO2AT) while CET increased the relative maximal oxygen uptake (RVO2max) to a statistically significant extent. However, intergroup comparison failed to show group-specific differences. Concerning coordinative tasks, the members of the StA group achieved a significant time reduction for both hands' tapping test. However, only the improvement in left-handed tapping was significantly higher than that achieved by members of the CET group. Despite the absence of group-specific differences, CET members showed a statistically significant change when comparing the duration of pre- with post-training time for one-leg stance under proprioceptive conditions. Team spirit was significantly higher in the StA group than in the CET group. Except for the time reduction in left-handed tapping, the present study found no group-specific differences in physical performance and coordination. Participating in a StA class has a more cohesive effect on the individual members than attending a CET group.

Adult↗

PubMed2002

Pulsed magnetic field therapy for osteoarthritis of the knee--a double-blind sham-controlled trial.

BACKGROUND AND METHODS: Pulsed magnetic field therapy is frequently used to treat the symptoms of osteoarthritis, although its efficacy has not been proven. We conducted a randomized, double-blind comparison of pulsed magnetic field and sham therapy in patients with symptomatic osteoarthritis of the knee. Patients were assigned to receive 84 sessions, each with a duration of 30 minutes, of either pulsed magnetic field or sham treatment. Patients administered the treatment on their own at home, twice a day for six weeks. RESULTS: According to a sample size estimation, 36 consecutive patients were enrolled. 34 patients completed the study, two of whom had to be excluded from the statistical analysis, as they had not applied the PMF sufficiently. Thus, 15 verum and 17 sham-treated patients were enrolled in the statistical analysis. After six weeks of treatment the WOMAC Osteoarthritis Index was reduced in the pulsed magnetic field-group from 84.1 (+/- 45.1) to 49.7 (+/- 31.6), and from 73.7 (+/- 43.3) to 66.9 (+/- 52.9) in the sham-treated group (p = 0.03). The following secondary parameters improved in the pulsed magnetic field group more than they did in the sham group: gait speed at fast walking [+6.0 meters per minute (1.6 to 10.4) vs. -3.2 (-8.5 to 2.2)], stride length at fast walking [+6.9 cm (0.2 to 13.7) vs. -2.9 (-8.8 to 2.9)], and acceleration time in the isokinetic dynamometry strength tests [-7.0% (-15.2 to 1.3) vs. 10.1% (-0.3 to 20.6)]. CONCLUSION: In patients with symptomatic osteoarthritis of the knee, PMF treatment can reduce impairment in activities of daily life and improve knee function.

Aged↗

PubMed2002

[Optimizing electrotherapy--a comparative study of 3 different currents].

Neuromuscular electrical stimulation can be used to increase strength of skeletal muscle. In neuromuscular electrical stimulation of innervated skeletal muscle, the application of the highest possible intensities of electricity is an important determinant of therapeutic success with regard to strength training. The therapeutic goal of "strengthening muscles" is opposed to the side effect of discomfort through the application of electricity. The aim of the present study was to compare three forms of electric current with respect to subjective tolerance and maximum achievable muscular strength. Twenty-nine healthy male volunteers were included in a single-blind study in which three forms of electric current were applied in a randomized fashion. The following types were compared: a short monophasic form, a biphasic form that was twice as long in terms of impulse duration, and a long monophasic form with an equal impulse duration than tht of the biphasic form and with an impulse form that corresponded to the short monophasic current. Stimulation was administered via surface electrodes placed on the knee extensors in the lower extremity on the right side. The intensity of the current was increased to the individual limit of tolerance or to a maximum of 100 mA. The main target parameter used to determine the success of treatment was the maximum electrically induced strength as a percentage of maximal voluntary contraction. The short monophasic form of electricity was associated with much less discomfort than the long monophasic and biphasic forms (p < 0.0001, p = 0.0062). Furthermore, the biphasic form was better tolerated (and therefore had a larger therapeutic range of application) than the long monophasic form (p = 0.041). The biphasic and long monophasic forms produced higher values for maximum electrically induced strength than did the short monophasic form (p = 0.0001, p = 0.0010). To summarize: the biphasic form had a larger range of therapeutic application than the long monophasic form. Furthermore, the biphasic form produced 40% more electrically induced strength than the short monophasic one. It may be concluded that, in terms of therapeutic application, the biphasic form of electric current is superior to the monophasic forms described in the present study.

Adult↗

PubMed2002

Postural control during lifting.

Any voluntary motion of the body causes an internal perturbation of balance. Load transfer during manual material handling may increase these perturbations. This study investigates effects of stance condition on postural control during lifting. Nineteen healthy subjects repeatedly lifted and lowered a load between a desk and a shelf. The base of support was varied between parallel and step stance. Ground reaction force and segmental kinematics were measured. Load transfer during lifting perturbed balance. In parallel stance postural response consisted of axial movements in the sagittal plane. Such strategy was accompanied by increased posterior shear forces after lift-off. Lifting in step stance provided extended support in anterior/posterior direction. The postural control mechanisms in the sagittal plane are less complex as compared to parallel stance. However, lifting in step stance was asymmetrical and thus accompanied by distinct lateral transfer of the body. Lateral shear forces were larger as compared to parallel stance. Both lifting techniques exhibit positive and negative aspects. We cannot recommend either one as being better in terms of postural control.

Adult↗

PubMed2002

Long-term outcome after treatment of temporomandibular joint osteoarthritis with exercise and manual therapy.

In a previous study, exercise and manual therapy demonstrated a 90% success rate in patients with osteoarthrosis of the temporomandibular joints in the short-term. The aim of this follow-up study was to assess the long-term effect of these treatment modalities. Seventeen patients were evaluated. All patients suffered from osteoarthrosis of the temporomandibular joints with pain in the temporomandibular joint at baseline and were treated successfully in a prior short-term study. The parameters were pain at rest and at chewing, impairment in daily life, and mouth opening. At follow-up, 11 patients (65%) experienced no pain and 13 patients (76%) had no pain at rest (Fisher's Exact Test: p<0.02). Thirteen patients (76%) had a normal incisal edge clearance, and ten patients (59%) felt no impairment due to the disease (Fisher's Exact Test: p=0.01). Thirteen patients (76%), who had been treated once successfully, have not needed treatment within the three years after cessation of their therapy. Exercise therapy is an effective tool to treat osteoarthrosis of the temporomandibular joints.

Activities of Daily Living↗

PubMed2002

Reliability of EMG time-frequency measures of fatigue during repetitive lifting.

PURPOSE: To test the short-term and long-term reliability of time-frequency electromyographic (EMG) measures of fatigue during repetitive dynamic lifting and compare it with the reliability of median frequency (MF) EMG measures of fatigue during static lifting. METHODS: Fourteen' healthy male subjects (26 +/- 5 years) repetitively (12 lifts/min) lifted and lowered a box (29 x 25 x 23 cm, 13 kg) for 4.5 min during 3 different tests on 2 different days. EMG data and the biomechanics of motion were recorded. Before and after dynamic lifting, static maximum lifting tests were performed. At the end of each of the two sessions, subjects performed a static lift at 80% of their maximum lifting force for 30 s. RESULTS: Significant fatigue-related changes were observed during the lifting exercise via EMG time-frequency analysis at the paravertebral L5, L2, T10, and vastus lateralis (VL) electrode sites. Two parameters for assessing fatigue during dynamic contractions [i.e., the Instantaneous Median Frequency (IMDF) and its time dependent change] were shown to be reproducible both in the short-term (2 h) and long-term (2 wk). The corresponding ICCs reflecting the reproducibility of values between sessions were 96.9% (L5), 98.1% (L2), 90.1% (T10), 96.4% (UT), 98.0% (GM), 89.5% (VL), and 99.0% (BF), respectively. For most EMG recording sites, the reliability of the IMDF measures was not dependent upon the postural strategy that the subject used to accomplish the lifting task or on the subject's strength as measured via the static maximum lifting test. A comparison between the ICC values of the IMDF measures and those of the parameters utilized to assess fatigue during static sustained lifts [i.e., the Median Frequency (MDF) and its change during the test] revealed equally good reproducibility for most EMG recording sites. The respective ICC values that took into account time dependent trends for the IMDF parameter were 87.1% (L5), 62.4% (L2), 90.1% (T10), 0% (UT), 72.7% (GM), 45.4% (VL), and 100% (BF), and for the MDF parameter 94.9% (L5), 73.0% (L2), 80.9% (T10), 100% (UT), 89% (GM), 91.7% (VL), and 90.9% (BF), respectively. CONCLUSIONS: The time-frequency approach allows one to derive EMG spectral parameters that can be used to monitor muscle fatigue during dynamic real-world tasks such as lifting.

Adult↗