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L R Osternig

Publications and source records attributed to L R Osternig.

28 records · Page 2Linked to original sources
PubMed1979

Functional variability of the lower extremity during the support phase of running.

The purpose of the research was to determine the variability of selected parameters during the support phase of running between consecutive right footfalls, and the included left footfall, as well as to acquire additional descriptive data on lower extremity function. Eleven college aged male runners were filmed (200 fps) from the rear and side while running on a treadmill at 4.29--4.47 m/sec. The statistical analysis of the mean absolute differences for temporal events between the three footfalls resulted in no significant differences. An estimate of event variability was calculated to be the actual time +/- 0.0110 sec or the percentage +/- 4.98% at the 95% confidence interval. Comparisons between the absolute deviations of selected body part positions and/or orientations for the test conditions resulted in no statistically significant differences. Estimates of variability ranging from 1.78--4.08 deg were calculated. Even though no statistically significant differences were obtained, the magnitude of the variability obtained for the parameters evaluated would seem to indicate a need for calculating representative or average values if subtle differences in lower extremity function are to be detected.

Adult↗
PubMed1978

Effects of electromyographic feedback training on motor control in spastic cerebral palsy.

Electromyographic feedback training may play a special role in increasing active range of motion in spastic cerebral palsied individuals. The effects of electromyographic feedback training were documented on four persons with spastic diplegic cerebral palsy within a single subject design. Subjects received immediate auditory and visual feedback twice daily during ten consecutive days. Electromyographic feedback training resulted in increases in the active range of motion of the ankle joint of from 20 percent to 500 percent in the limbs trained during the first five days with electromyographic feedback and of from 33 percent to 450 percent in the limbs trained in the last five days. The acquired active range of motion was maintained by two of the subjects over intervals of from four to nine weeks.

Adolescent↗
PubMed1977

Isokinetic and isometric torque force relationships.

The torque forces of elbow extensor musculature of 28 men were tested with an isokinetic dynamometer to determine the relationships between maximal isokinetic torque generated at various speeds and maximal isometric forces at specified angles in the arc of elbow extension. The men were tested at constant velocities ranging from 5 to 25 rpm and at angles of elbow extension ranging from 10 degrees to 90 degrees. Product-moment correlation coefficients were calculated between the maximum isometric torque developed at each of the measured angles and the isokinetic torque generated at each of the predetermined speeds. Of the 81 correlation coefficients calculated, 13 differed significantly from zero. There were slight tendencies for the significant correlations to cluster toward the slower speeds and toward the greater angles of elbow flexion. It was suggested that the slight tendency for higher correlations to cluster toward the slower speeds may be due to slower speeds stimulating isometric effort. The slight tendency for the higher correlations to cluster toward the greater angles of elbow flexion may be due to variances in the consistency of muscular strength at different muscle lengths. Since the highest correlation attained yielded a common variability of less than 24% between the two variables tested, it was concluded that measures of isokinetic strength cannot be used to predict isometric strength capabilities.

Adult↗
PubMed1975

Optimal isokinetic loads and velocities producing muscular power in human subjects.

The torque values of the quadriceps muscles of 16 college football players were tested by means of an isokinetic dynamometer in order to determine the optimal loads and velocities producing muscular power. The men were tested at velocities ranging from 5 to 25 rpm and throughout a range of knee extension between the positions of 85 degrees to 50 degrees of knee flexion. Isometric measures were also recorded at corresponding angles. The muscular torque values recorded isokinetically at the various velocities were then compared to the isometric forces at the corresponding angles of knee extension to ascertain the arithemtic proportion of isokinetic to isometric torque which produced maximum muscular power. The results indicated that the proportionate values of isokinetic to isometric torque and isokinetic velocities which produced maximum power were not directly comparable to similar loads and velocities found in vitro. The weight of the leg may have contributed to submaximal isometric recordings, thus resulting in higher proportionate values of isokinetic to isometric force. Changes in these values as the knee was extended were deemed to be a result of variance in the isometric torque since the isokinetic torque stayed relatively constant throughout the range of movement. The data suggested that a plateau of isokinetic torque may have been reached in the production of maximum power. Maximum isokinetic torque values tended to shift to more extended joint positions as the speed of knee extension increased. This shift may have been due to the momentum of the leg during the faster isokinetic speeds overcoming some of the inertia of the weight of the leg as it was extended.

Adolescent↗
PubMedDate not supplied

Injuries to runners.

Explore the source record for details and available documents.

Adolescent↗
PubMedDate not supplied

Foot orthotic devices to modify selected aspects of lower extremity mechanics.

Excessive foot pronation has been speculated to be a cause of leg and foot problems among runners. Foot orthotic devices are often used to modify this condition. Examination of the records of 180 patients treated for various running injuries showed that 83 individuals (46%) were prescribed orthotic devices and that 65 of these runners (78%) were able to return to their previous running programs. In order to assess further the effects of this type of orthotic device, six runners were selected from this group and filmed using two cameras (200 frames/sec) under three conditions: (1) barefoot, (2) regular shoe, and (3) regular shoe plus orthotic device. Both the period of pronation and the amount of maximum pronation were significantly reduced by using the foot orthotic device. The data support the conclusion that foot orthotic devices can be successfully used to modify selected aspects of lower extremity mechanics during the support phase of running.

Ankle↗
PubMedDate not supplied

Long-term evaluation of knee stability and function following surgical reconstruction for anterior cruciate ligament insufficiency.

Currently used measures of knee stability and function for ACL reconstructed knees have not gained universal acceptance. Clinical test results often are given more value than the patient's subjective evaluation of the surgical outcome. This study was designed to identify specific knee stability and function variables that were most predictive of the patient's rating of knee function following one of two types of combined (intraarticular and extraarticular) ACL reconstruction procedures. Individual measures of knee stability and function were also evaluated for differences between contralateral operated and nonoperated limbs. Postoperative and healthy contralateral knees of 51 male and female patients aged 18 to 49 years (mean, 23.7 years) were evaluated on a battery of tests at an average of 48.0 months after surgery (range, 24 to 101 months). All subjects possessed a normal contralateral knee for comparative purposes. The results of this retrospective study indicated that the variables selected were not highly correlated with, nor could they effectively predict, the patients' perceptions of postoperative knee status as measured by the Knee Function Rating Form (KFR). Statistically significant differences (P less than 0.001) between operated and nonoperated knees were found for 9 of 11 variables analyzed. The data suggest that patients' perceptions of postoperative knee status were independent of the results of static and dynamic clinical tests commonly used to assess knee stability and function. Postoperative deficits of up to 30% between the surgically reconstructed and normal contralateral knees on specific measures of knee stability and function did not greatly influence the patients' perceptions of knee function. Development of new, more specific dynamic tests may be necessary before stronger relationships between clinical test results and patients' perceptions of knee status in the ACL reconstructed knee can be realized.

Adolescent↗
PubMedDate not supplied

Effects of prophylactic knee bracing on lower extremity joint position and muscle activation during running.

The primary purpose of a prophylactic knee brace is to decrease injury potential without compromising joint function; however, the extent that these devices can alter knee muscle function is not clear. This study investigated effects of nonprescription prophylactic knee bracing on lower extremity joint position and muscle activation during running. Six healthy male college-aged recreational runners used a motor-driven treadmill under 6 conditions: fast or slow speeds, with and without wearing a prophylactic knee brace, and with and without wearing a weighted vest. Changes in hip, knee, and ankle joint position and electromyographic activity from 9 lower extremity muscles were monitored during the running cycle weightbearing phase. Results revealed significant changes (P < 0.05) in joint position and electromyographic activity for comparisons of slow versus fast, braced versus nonbraced, and weighted versus nonweighted conditions. From 83% to 89% of the braced and nonbraced comparisons generated significant differences in knee joint position while significant hip and ankle joint position changes occurred in 50% to 58% of comparisons. From 67% to 83% of braced and nonbraced comparisons for the 9 muscles produced significant differences in electromyographic activity. Findings suggest that neuromuscular control is altered when external prophylactic devices are applied.

Adult↗