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Biomedical subjects

J A Nicholas

Publications and source records attributed to J A Nicholas.

78 records · Page 5Linked to original sources

The efficacy of manual assessment of muscle strength using a new device.

The purpose of this study was to compare the manual assessment of muscle strength with a small, handheld (by the examiner) force-measuring device developed by the Institute of Sports Medicine and Athletic Trauma (ISMAT). One hundred twenty-eight patients presented with a known lower extremity orthopaedic pathology. All patients were clinically evaluated for hip abductor and hip flexor weakness in standard positions using the "break test" technique. All 128 patients were then evaluated with the ISMAT Manual Muscle Tester, a small, hand-held device which recorded the peak force (kg) required to break a muscle contraction. Three bilateral measures of hip abduction and hip flexion were recorded, averaged, and compared to the subjective clinical evaluation using a chisquare analysis. Bilateral values which were within 5% of each other were not considered significant and therefore not included in the calculations. The average hip abduction and hip flexion scores measured by the ISMAT tester were consistent with the examiner's perception of muscle weakness (P less than 0.001). The results demonstrate consistent detection of muscle weakness by the ISMAT Manual Muscle tester over a broad range of testing conditions.

Humans↗

Hand and forearm strength and its relation to tennis.

Eight expert tennis players and 12 nontennis playing controls were studied to determine the relationship between dominant and minor extremities in regard to hand and forearm isometric strength. The results revealed that overall strength, including wrist extension, was significantly greater (P 0.01) in the dominant arm in both groups. The tennis players were distinguished from the controls by significantly increased strength of metacarpophalangeal joint extension of the fingers on the dominant side. Examination of a group of 16 "tennis elbow" sufferers demonstrated no significant extensor strength differential in the dominant arm, with no reports of pain during the testing procedure. The increased strength of hand extension in elite tennis players may be significant in explaining the observed rarity of "tennis elbow" in these individuals.

Forearm↗

Metabolic costs and heart rate responses to treadmill walking in water at different depths and temperatures.

Treadmill walking/jogging in water is a potentially useful therapeutic modality. Since energy costs of this activity are unknown, we compared oxygen consumption (VO2) of treadmill walking/jogging in water to a dry treadmill at speeds of 40.23 to 160.9 meters/min (m/m) in 13.4 m/m increments in 11 subjects. At speeds greater than or equal to 53.6 m/m, ankle depth, below knee, midthigh, and waist depth walking/jogging in water significantly elevated VO2 and heart rate (HR) above dry treadmill walking (P less than 0.05). At speeds greater than or equal to 134.1 m/m, VO2 of waist depth jogging was not significantly greater than dry jogging. These findings showed no gender specificity. Treadmill walking/jogging in waist depth water at temperatures of 30.5 degrees C and 36.1 degrees C was compared to dry treadmill walking in five subjects. The rate of increase of HR compared to VO2 was significantly greater at 30.5 degrees C than dry walking, and greater at 36.1 degrees C than 30.5 degrees C (P less than 0.05). Treadmill walking in water can double the oxygen cost of movement depending on the depth and speed, and the response to increasing speed is nonlinear. Water temperature affects the relationship of HR to VO2 at waist depth, suggesting that water temperature can add a significant thermal load to the cardiovascular system. Metabolic and cardiovascular demands of treadmill walking/jogging in water must be considered when using this modality since greater external work results at much lower speeds than on land.

Adult↗

Subject variability of shoulder abduction strength testing.

To quantify normal biological variability of shoulder abduction strength testing with an isokinetic and a hand-held dynamometer, we tested nine healthy subjects over a clinically relevant period. One side was tested with a Cybex at 60 deg/sec and the other with a hand-held dynamometer. Six maximal trials, following warmup, were conducted on each of 5 days, separated by 1 to 2 weeks. Intraday correlations of individual trials ranged from 0.82 to 0.995 for hand-held dynamometer, and 0.88 to 0.996 for Cybex. Interday correlations ranged from 0.94 to 0.98 for hand-held dynamometer, and 0.88 to 0.97 for Cybex. The best values to use for Cybex interday variability were the average of the first three repetitions, and yielded standard errors of 8.6% to 19.2% of the sample mean. The average of the last three repetitions were the best for hand-held dynamometers, and yielded standard errors of 5.5% to 10.8%. There was a significant decline (P less than 0.05) in strength of the mean of the last three versus the mean of the first three daily repetitions on Day 1 and 4 for hand-held dynamometers, and a trend toward this on the other days, that was not seen with Cybex. Regression of average Day 1 values for Cybex and hand-held dynamometer yielded r = 0.86 (P less than 0.01) with a slope of 1.07 indicating good agreement between modalities. In conclusion, intraday/interday correlations were high for Cybex and hand-held dynamometer. Interday variability was minimized by using the mean score of the first three and last three repetitions for Cybex and hand-held dynamometer, respectively. Changes in Cybex and hand-held dynamometer strength of less than 19% and 11%, respectively, are within the area of "measurement error" and should therefore not be considered clinically significant.

Adult↗

Bracing the anterior cruciate ligament deficient knee using the Lenox Hill derotation brace.

The Lenox Hill derotation brace fashioned by Castiglia and his staff at the Lenox Hill Hospital Brace Shop (New York, New York) under the direction of Nicholas during the 1960s has been worn successfully by thousands of patients with unstable knees, including elderly arthritic patients, adolescents with congenital instability, and professional athletes. Nearly 9000 braces were worn by patients in the United States during the period from 1976 to 1980. The brace, with its sliding axis of motion, corresponds to the axis of movement in the knee. The combination Lenox Hill brace includes not only the sliding axis of motion, but also a second below-knee leg pad, second derotation strap, and hyper-extension stop. It is designed to resist the combination anteromedial-rotatory, anterolateral-rotatory, and anteromediolateral-rotatory instabilities. More than 70% of the braces prescribed during the last five years have been the combination type. The derotation brace is a significant advance in brace designs for supporting chronic unstable and surgically reconstructed knees. It can function effectively even when the wearer is actively participating in sports.

Athletic Injuries↗