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R L Gajdosik

Publications and source records attributed to R L Gajdosik.

16 recordsLinked to original sources
PubMed1999

Concentric isokinetic torque characteristics of the calf muscles of active women aged 20 to 84 years.

STUDY DESIGN: Descriptive, comparative, and correlational study of nonimpaired, active women in 3 age groups. OBJECTIVES: We described age-related concentric isokinetic torque of plantar flexion (PF) of active women and examined the proposal that PF torque at slow to rapid velocities would be influenced by age-related slower muscle contractile properties. We also examined the relationship of age to passive and active force characteristics of the calf muscle. BACKGROUND: Aging is associated with decreased calf muscle strength, slower muscle contractile properties, and decreased dorsiflexion (DF) range of motion. Clinical methods of measuring these changes in the calf muscles have not been described adequately. METHODS AND MEASURES: 24 younger women (20 to 39 years), 24 middle-aged women (40 to 59 years), and 33 older women (60 to 84 years) performed maximal concentric PF of the right ankle from maximal passive DF at randomly ordered velocities of 30 degrees.s-1, 60 degrees.s-1, 120 degrees.s-1, and 180 degrees.s-1. The peak and mean torques and "angular delay" (degree) from the onset of movement to peak torque were examined using ANOVA. Age was correlated (Pearson product moment r) with the peak and mean torques, "angular delay," velocity at peak torque for 180 degrees.s-1, and the maximal passive DF angle and torque. RESULTS: The peak and mean torques decreased with increasing age and velocities. The angular delay at 180 degrees.s-1 decreased with increasing age. Age was negatively correlated with the peak and mean torques (range, r = -0.60 to -0.73), the "angular delay" at all velocities (range, r = -0.44 to -0.64), the maximal passive DF angle (r = -0.73) and torque (r = -0.60), and with the peak torque velocity at 180 degrees.s-1 (r = -0.29). CONCLUSIONS: The results indicate age-related changes for the concentric isokinetic torque of the calf muscles of active women. The angular delay at 180 degrees.s-1 may show changes influenced by slower muscle contractile properties. Concurrent age-related declines in passive and active calf muscle force characteristics were demonstrated.

Adult↗
PubMed1999

Influence of age on length and passive elastic stiffness characteristics of the calf muscle-tendon unit of women.

BACKGROUND AND PURPOSE: Therapeutic stretching of the calf muscle-tendon unit is used to increase its length and to ameliorate decreased dorsiflexion range of motion (ROM), but the influence of age on the passive properties of the calf muscle-tendon unit has not been studied adequately The purpose of this study was to examine the influence of age on length and passive elastic stiffness (PES) characteristics of the calf muscle-tendon unit when stretched through the full, available dorsiflexion ROM. SUBJECTS: Twenty-four younger women (aged 20-39 years), 24 middle-aged women (aged 40-59 years), and 33 older women (aged 60-84 years) participated. METHODS: An isokinetic dynamometer was used to passively stretch the right calf muscle-tendon unit from relaxed plantar flexion to the maximal angle of available dorsiflexion at 5(ús-1. The maximal passive resistive torque was measured, and passive angle-torque curves were constructed for a full ROM from an initial angle of passive resistive torque to the maximal dorsiflexion angle. The full ROM represented length extensibility. The average PES was calculated for this full stretch ROM and for the first half and the last half of this stretch ROM. The maximal passive dorsiflexion angle, maximal passive resistive torque, angular change for the full stretch ROM, and average PES for the full stretch ROM and the first half and the last half of the full stretch ROM were examined for group differences and their relationships with age. RESULTS: The maximal passive dorsiflexion angle, maximal passive resistive torque, angular change for the full stretch ROM, and average PES within the last half of the full stretch ROM were less for the older women than for the younger women. Age was negatively associated with these variables. CONCLUSION AND DISCUSSION: Decreased maximal passive dorsiflexion ROM in older women was associated with decreased maximal passive resistive torque, decreased calf muscle-tendon unit length extensibility, and decreased average PES within the last half of their available passive dorsiflexion ROM.

Adult↗
PubMed1997

Accuracy and variability of leg velocities during concentric and eccentric actions of the quadriceps femoris muscles.

This study examined the ability to control leg velocities during concentric and eccentric actions of the right quadriceps muscles. Ten healthy women (M age = 25.9 +/- 3.5 yr.) were tested using the Isotonic Program of the KIN-COM II 500H dynamometer. They attempted to match velocity tracings of 10 degrees, 20 degrees, and 40 degrees/sec. through 70 degrees of knee range of motion at a load equal to 10% of their maximal mean concentric force. The actual mean velocities, mean percent deviation from the target velocities, and the coefficient of variation for both actions were calculated for 15 degrees-75 degrees (full range of motion), 15 degrees-45 degrees (shorter range of motion), and 46 degrees-75 degrees (longer range of motion). Separate one-way analyses of variance with two trial factors (action x velocity) showed faster concentric velocities through the full and longer ranges of motion, and faster eccentric velocities through the shorter range of motion. Mean percent deviations indicated that the eccentric velocities were generally more accurate within all ranges of motion. Larger concentric coefficients of variation were found within the full and longer ranges of motion, and the coefficients of variation for both actions decreased as the velocities increased. An exaggerated 'velocity overshoot' at the onset of both actions probably contributed to differences in the velocities and coefficients of variation. The results indicated differences between the concentric and eccentric actions, explained in part by the testing methodology used and by the known mechanical and physiological characteristics of the two muscle actions.

Adult↗
PubMed1996

Influence of age on concentric isokinetic torque and passive extensibility variables of the calf muscles of women.

The purpose of this study was to investigate the influence of age on concentric isokinetic torque (CIT) and passive extensibility (PE) variables of the calf muscles of healthy women. Ten younger women [31.9 (SD 6.1) years] and ten older women [71.1 (SD 6.6) years] were tested using a KIN-COM 500H dynamometer. The PE was tested by stretching the muscles from relaxed plantarflexion to the maximal dorsiflexion (DF) angle at 5 degrees.s-1 without raw electromyogram (EMG) activity exceeding 0.05 mV. The maximal CIT was tested from the maximal DF angle 60 degrees into plantarflexion at four randomly ordered velocities of 30,60, 120, and 180 degrees.s-1. Separate analysis of variance (ANOVA) tests showed that the standardized (% body mass) concentric peak and mean torques were lower for the older women for all isokinetic velocities (p < 0.001). The "angular delay" from the onset of concentric activation to peak torque was smaller for the older women at 120 and 180 degrees.s-1 (p < 0.05). Age showed negative relationships (Pearson r) with all standardized peak torques (p < or = 0.001) and mean torques (p < 0.001), and the "angular delay" at 120 and 180 degrees.s-1 (p < or = 0.05). Independent t-tests showed that the maximal DF angle and the change in the PE angle from an initial angle (defined at 10% of the maximal passive torque) to the maximal DF angle were less for the older women (p < 0.05). Age was negatively related to the maximal DF angle and the change in the PE angle (p < 0.01). The results suggest an age-related decrease in calf muscle CIT, muscle length and PE. The smaller "angular delay" for the older women at 120 and 180 degrees.s-1 indicates that CIT testing at rapid velocities can be used to examine age-related changes in calf muscle contractile properties in relation to rapid velocities of movement.

Adult↗
PubMed1994

Q angle: effects of isometric quadriceps contraction and body position.

The quadriceps femoral angle (Q angle) has been linked with several knee disorders, but Q-angle measurement procedures have not been standardized. The purpose of this study was to examine the effects of isometric quadriceps contraction in the standing and supine positions on the Q angle. The Q angles of the right knees of 30 men and 30 women were measured goniometrically during four test conditions: 1) quadriceps relaxed in standing, 2) quadriceps contracted in standing, 3) quadriceps relaxed in supine, and 4) quadriceps contracted in supine. The pelvic widths were also measured as the distance between the anterior superior iliac spines in standing and supine. A two-way multivariate analysis of variance showed a significant difference between genders (p < 0.001) and among the four test conditions (p < 0.001) (N = 60). Separate one-way analyses of variance (ANOVAs) with two grouping factors (contraction and position) showed significant effects of contraction (p < 0.001) for both men and women, but no significant effect of positions. A dependent t-test showed that the pelvic width differed between standing and supine for both men and women (p < 0.001). The results showed that isometric quadriceps contraction affects the Q angle with the subjects standing or supine, even though the pelvic width differed significantly between the two positions. Clinicians and researchers should consider the results of this study in order to standardize procedures for measuring the Q angle.

Adult↗
PubMed1994

Influence of hamstring length on the standing position and flexion range of motion of the pelvic angle, lumbar angle, and thoracic angle.

Hamstring muscle length may be associated with specific pelvic and trunk postures, but the influence of hamstring length on trunk postures is not well documented. The purposes of this study were to examine the influence of hamstring length on 1) the pelvic angle, lumbar angle, and thoracic angle in standing; and 2) the flexion ranges of motion of the pelvic angle, lumbar angle, and thoracic angle during the toe-touch test. Surface platform pointers over bony landmarks and photography were used to examine the pelvic and trunk angles and ranges of motion of 10 men with short hamstrings, 10 men with medium hamstrings, and 10 men with long hamstrings while standing and after assuming the toe-touch position. Separate one-way analyses of variance detected no significant differences among groups for the three angles in standing. Significant differences were detected among groups for the three angles in the toe-touch position and the flexion ranges of motion during the toe-touch test (p < 0.05). Short hamstrings were associated with decreased flexion range of motion of the pelvic angle and lumbar angle and increased flexion range of motion of the thoracic angle. Therapeutic interventions should be considered in light of the influences of hamstring length on the flexion range of motion of the pelvic angle, lumbar angle, and thoracic. angle.

Adult↗
PubMed1993

The stretch-shortening cycle of the quadriceps femoris muscle group measured by isokinetic dynamometry.

The ability to measure the stretch-shortening cycle of isolated muscle groups has been limited. The purpose of this study was to measure the stretch-shortening cycle of the quadriceps femoris muscle group. Twenty-four volunteer subjects, 12 men and 12 women, participated in one test session; five men and five women also participated in a retest session; to examine the reliability of the test. A concentric contraction of the left quadriceps was measured for peak torque and time to peak torque on a Biodex isokinetic dynamometer under three conditions: 1) passive stretch before a concentric contraction, 2) isometric preload before a concentric contraction, and 3) eccentric preload before a concentric contraction. Conditions 2 and 3 showed a significant increase in peak torque production compared to condition 1 (p < 0.01). A significant difference was found for all three conditions between the men and women, with the men producing greatest peak torques. Conditions 2 and 3 also showed a significantly decreased time to peak torque compared with condition 1 (p < 0.01). The testing protocol was found to have high reliability. This testing protocol could be used to further study the stretch-shortening cycle in the quadriceps femoris muscle group.

Adult↗
PubMed1993

Comparison of four clinical tests for assessing hamstring muscle length.

Several indirect clinical tests for measuring hamstring muscle length are available, but the influence of their test procedures is not well documented. This study examined four of these tests to clarify the results relative to the testing procedures. The right limbs of 30 men were tested for: 1) passive straight leg raise (SLR) with the pelvis and opposite thigh stabilized with straps (SLR-SS); 2) passive SLR with the low back flat and, if needed, the opposite thigh slightly flexed and supported on pillows (SLR-LBF); 3) active knee extension with the hip at 90 degrees (AKE); and 4) passive knee extension with the hip at 90 degrees (PKE). A dependent t-test showed no significant differences between the angles of SLR-SS (61 degrees +/- 6.7 degrees) and SLR-LBF (62 degrees +/- 6.2 degrees). The SLR-SS and SLR-LBF angles for subjects needing pillows under the opposite thigh for the SLR-LBF test (N = 18) also were not significantly different. The knee flexion angles for the AKE (43 degrees +/- 10.2 degrees) and the PKE (31 degrees +/- 7.5 degrees) tests were significantly different (p < 0.001). Significant relationships (Pearson r) were found among the four tests (p < 0.05). The similar angles for SLR-SS and SLR-LBF and their significant relationship (r = 0.70, p < 0.001) indicated that their different testing procedures probably had a minimal influence on test results. The difference between the AKE and PKE tests suggested that the AKE test and the PKE test may represent an "initial length" and a "maximal length," respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1987

Clinical measurement of range of motion. Review of goniometry emphasizing reliability and validity.

Clinical measurement of range of motion is a fundamental evaluation procedure with ubiquitous application in physical therapy. Objective measurements of ROM and correct interpretation of the measurement results can have a substantial impact on the development of the scientific basis of therapeutic interventions. The purpose of this article is to review the related literature on the reliability and validity of goniometric measurements of the extremities. Special emphasis is placed on how the reliability of goniometry is influenced by instrumentation and procedures, differences among joint actions and body regions, passive versus active measurements, intratester versus intertester measurements, and different patient types. Our discussion of validity encourages objective interpretation of the meaning of ROM measurements in light of the purposes and the limitations of goniometry. We conclude that clinicians should adopt standardized methods of testing and should interpret and report goniometric results as ROM measurements only, not as measurements of factors that may affect ROM.

Humans↗
PubMed1987

Spinal nerve root compression--some clinical implications. A review of the literature.

Spinal nerve root compression (SNRC) lesions resulting from various etiological conditions are a problem affecting many patients seen by physical therapists. The purposes of this article are to describe the factors that determine the strength deficits (SDs) accompanying these lesions and to discuss evaluation procedures and therapeutic considerations for patients with these SDs. Because of biological compensatory mechanisms and the shortcomings of techniques for measuring SDs, physical therapists may be unaware of the motor involvement of patients with SNRC lesions. The application of appropriate evaluation procedures should enable physical therapists to identify the SDs and monitor their response to therapeutic interventions. These interventions should be applied with appreciation of the potential for causing further damage from overworking the weakened muscles.

Humans↗
PubMed1986

Isokinetic knee flexion and extension torque in the upright sitting and semireclined sitting positions.

We undertook this study to determine whether the isokinetic knee extension and flexion torque generated by 14 young healthy women was greater in the upright sitting test position or in the semireclined sitting test position. Testing was performed at 60 degrees/sec. Knee extension torque did not differ significantly between the two test positions. The subjects, however, did produce significantly greater knee flexion torque when upright compared with when semireclined (p less than .001). Therapists should recognize that the results of testing isokinetic knee extension in the two positions may be similar, but that the results of testing isokinetic knee flexion may be significantly different.

Adult↗
PubMed1985

Effects of ankle dorsiflexion on active and passive unilateral straight leg raising.

The purpose of this study was to analyze the straight-leg-raising (SLR) maneuver while the ankle was fixed in dorsiflexion or relaxed in plantar flexion. Twenty-two healthy subjects underwent active and passive SLR with the ankle in each position. We used cinematography to document movement of the right lower limb and pelvis and electromyography to document hamstring muscle activity. Analyses of variance of the angles of maximum SLR and change in the pelvic position showed a significant F ratio (p = .01) among the active and passive trials. Post hoc analyses demonstrated significant differences (p = .01) between SLR with dorsiflexion and SLR with plantar flexion. The EMG activity among trials was not significantly different. The possible causes of the effects of dorsiflexion on SLR are discussed. We encourage clinicians to document and compare SLR with dorsiflexion and SLR with plantar flexion, and we recommend additional research to examine the relative influence of tissue structures on SLR.

Adult↗
PubMed1985

Relationship of pelvic and thigh motions during unilateral and bilateral hip flexion.

We filmed the hip flexion movement with a 16-mm motion picture camera to determine if a synergistic relationship between the pelvis and thigh existed. Seventeen young subjects, whose pelvises and thighs were marked with tape, underwent active and passive, unilateral and bilateral hip flexion while in the supine position. Analysis of the film revealed that the hip flexion movement is composed of two components--pelvic rotation and flexion of the thigh on the pelvis. Between one fourth and one third of the hip flexion movement was the consequence of pelvic rotation. This rotation always occurred within the first 8 degrees of the hip flexion movement. When therapists evaluate and treat patients with disorders of the thigh, pelvis, or lumbar spine, they should be aware that these structures normally move in synergy with one another. We suggest that the pelvifemoral relationship be examined further in studies with a wide range of healthy subjects and patients with a variety of clinical disorders.

Adolescent↗