Relative Peak Torque Research Articles

Isokinetic evaluation of the ankle plantar and dorsiflexion strength to determine the dominant limb in basketball players

The purpose of this study was to demonstrate limb dominance normative strength values (peak torque, relative peak torque, work and relative work) for the plantar and dorsiflexion muscles in professional basketball players, using the Cybex 1200 isokinetic dynamometer. Paired t-tests showed no significant differences between the two limbs, except for peak torque and relative peak torque during plantar flexion at 60°/s (p < 0.05). The ratio plantar/dorsiflexion was also analyzed, with no significant difference between the two limbs. The results of this research study provide very useful information about the level of strength in this particular area, and are useful for prescribing proper rehabilitation programs for injured basketball players.

TIBIAL ROTATION STRENGTH DEFICITS POST-ACL RECONSTRUCTION: HAMSTRING vs. PATELLAR TENDON AUTOGRAFTS

1761 Approximately 50,000 ACL reconstructions are performed in the United States annually1. While many (76%) surgeons use bone-patella tendon-bone (BTB), 21% use (medial) hamstring autographs for their primary reconstruction2. The purpose of this study was to determine internal tibial rotation (ITR) and external tibial rotation (ETR) peak torque differences between hamstring and BTB reconstructed patients. Patient inclusion criteria were: ≥ 1yr. post surgery and a normal contralateral knee. 46 patients, 23 (16 male, 7 female) treated with BTB autograft and 23 (9 male: 14 female) treated with hamstring autograft reconstruction were positioned on a Cybex in a supine position with the hip at 60° and the knee and ankle at 90° of flexion. Five maximal, concentric, ITR and ETR peak torque values were recorded and averaged during three isokinetic speeds (60, 120, 180°/sec). Relative ITR and ETR peak torque deficits were calculated by subtracting the absolute score of the involved limb from the score of the uninvolved limb. Between group, relative ITR and ETR peak torque deficits were compared using an unpaired t-test (p ≤ 0.05). Results showed that relative ITR peak torque deficits of the hamstring group were 2.6, 3.0 and 3.2 foot/lbs. at angular velocities of 60, 120, and 180°/sec. The relative ITR peak torque of BTB group were 0.7, 0.3, and 0.4 foot/lbs. There were significant differences between the magnitudes of relative ITR peak torque deficits at all speeds (p ≤ 0.02). The relative ETR peak torque deficits of the hamstring group were −0.7, 0.0, and −0.7 foot/lbs. at speeds of 60, 120, and 180°/sec. The relative ETR peak torque deficits of the BTB group were 2.4, 2.1, and 1.6 foot/lbs. There were significant differences between the magnitudes of the ETR peak torque deficits between groups at all speeds (p ≤ 0.01). The type of ACL reconstruction surgery has a residual effect on the ability to generate ITR and ETR peak torque.

Isokinetic evaluation of calf muscle performance after Achilles rupture repair.

The purposes of this study was 1) to assess the plantar flexion and dorsiflexion peak torques (PT) of the ankles at 30, 90 and 240.. s-1 in 101 patients (86 men, 15 women) who had been operated on for unilateral, complete closed Achilles tendon (AT) rupture at Oulu University Hospital, Oulu, Finland, in the period 1987-1992, 2) to determine whether comparison between the legs shows any impairment, 3) to study whether the weakness is speed-dependent, 4) to determine at what angular displacement of the ankle the weakness is manifested, 5) to study how the results correlate with age, type of operation and follow-up time. The Lido Multi-joint II dynamometer was used for the measurements. There was no significant dorsiflexion weakness detectable upon comparison between the legs, but the mean relative peak torque deficits in the injured limb were 8.4, 9.0 and 3.0% at 30, 90 and 240.. s-1 respectively for the men and 15.0, 16.6 and 6.4% for the women. The mean percentage torque differences were significantly greater in the women at all the test speeds (p < 0.05). The difference in PT was significantly greater at the two low test speeds (30 and 90.. s-1) than at the high speed (240.. s-1, p < 0.001). The weakness was manifested at an angular displacement of 80-120 degrees, where the average peak work (PW) difference between the two legs was significant in both sexes (p < 0.05). The patient's age (21-63), the type of operation (Lindholm or Silfverskiöld technique) and the follow-up time (0.7-6.7 years) did not significantly affect the results. In conclusion, and AT rupture implied an average 3.0 to 16.6% impairment in isokinetic plantar flexion muscle strength. The impairment was greater in the women, was manifested at an angular displacement of 80-120 degrees, and was greater at low test speeds. Age, type of operation and follow-up time did not account for the PT differences between the patients.

Seasonal Changes in Body Composition, Strength, and Muscular Power in High School Wrestlers

The purpose of this investigation was to determine the changes in body composition, isokinetic strength, and muscular power in high school wrestlers across a season of competition. Wrestlers were measured (preseason and postseason) for body composition and isokinetic peak torque for flexion and extension of the dominant forearm and leg. Each subject also completed Wingate anaerobic tests to determine changes in mean power and peak power (PP) of the legs. The results indicated that body weight (BW), fat weight, and percent fat decreased (p &lt; .002) across the wrestling season. PP and absolute peak torque for forearm and leg extension (LE) at 30°·s−1; forearm flexion (FF) at 30, 180, and 300°·s−1; and leg flexion (LF) at 180 and 300°·s−1 were significantly (p &lt; .05) lower postseason. Relative peak torque (adjusted for BW) decreased (p &lt; .05) across the season for LE at 30°·s−1 as well as FF and LF at 180°·s−1. Therefore, changes in BW were not associated with functional advantages in terms of strength or muscular power.

Muscle function in chronic compartment syndrome of the leg.

Chronic compartment syndrome (CCS) is a recognized cause of recurrent leg pain in the exercising patient. Decreased muscle function has been implied in this condition. This study compared the ankle dorsiflexion torque of 10 CCS patients with that of 18 control subjects during 20 repeated, maximal, isokinetic contractions at 60 degrees/sec. Peak torque, relative peak torque, and endurance data were collected. Results showed significantly lower peak torque and relative peak torque in the CCS group (p < or = 0.05), supporting the implication of muscle weakness in CCS. Paradoxically, endurance was significantly higher in the CCS group (p < or = 0.01), and there was a significant (p < or = 0.01), negative correlation (r = -0.50) between peak torque and endurance. The relationship between the findings and CCS is discussed. Strengthening may be useful in very mild cases or in postfasciotomy patients.

Isokinetic Peak Torque and Work Values for the Shoulder

The purposes of this study were to: a) measure peak torque (PKT) at 60 and 180 degrees /sec of angular velocity and work data at 180 degrees /sec of angular velocity for isokinetic muscular performance during external/internal rotation (ER/IR) and modified abduction/adduction (MOD-AB/AD) tests, b) compare the dominant and nondominant upper extremity data, and c) compare the relative peak torque between sexes. Twenty-one males and 20 females were tested isokinetically at 60 and 180 degrees /sec in MOD-AB/AD and ER/IR. A significant difference did not exist between the dominant and nondominant shoulders for the PKT. A significant difference did exist between sexes when comparing PKT, total work, and power but not when comparing endurance and agonist/antagonist PKT and work ratios. The data described demonstrated large standard deviations suggesting the need for specific categorization of persons to establish normative values. J Orthop Sports Phys Ther 1989;10(7):264-269.

Isokinetic Evaluation of the Ankle Invertors and Evertors

The purpose of this study was to develop normative strength dues (absolute peak torque and relative peak torque) for the ankle inverters and evertors in normal adults by using the Cybex dynamometer. Differences in strength between men and women, as we// as between dominant leg and nondominant leg, were also compared. Absolute peak torque of the two muscle groups in men were significantly higher (p < 0.001) than in women. When expressed as relative peak torque, however, only the left evertors in men were significantly stronger than the corresponding side in women. No Significant difference in strength ( p < 0.01) was found between the dominant leg and nondominant leg with the exception of the evertors in women when tested at 30 degrees per second. The ratios between the strength of the evertors and invertors were also presented; however, no apparent trend was noted. The data presented could provide a guideline for rehabilitation of patients.'J Orthop Sports Phys Ther 1984;5(5):246-252.