Joint stability characteristics of the ankle complex after lateral ligamentous injury, part I: a laboratory comparison using arthrometric measurement.

Context: The mechanical property of stiffness may be important to investigating how lateral ankle ligament injury affects the behavior of the viscoelastic properties of the ankle complex. A better understanding of injury effects on tissue elastic characteristics in relation to joint laxity could be obtained from cadaveric study.

Objective: To biomechanically determine the laxity and stiffness characteristics of the cadaver ankle complex before and after simulated injury to the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) during anterior drawer and inversion loading.

Joint stability characteristics of the ankle complex in female athletes with histories of lateral ankle sprain, part II: clinical experience using arthrometric measurement.

Context: This is part II of a 2-part series discussing stability characteristics of the ankle complex. In part I, we used a cadaver model to examine the effects of sectioning the lateral ankle ligaments on anterior and inversion motion and stiffness of the ankle complex. In part II, we wanted to build on and apply these findings to the clinical assessment of ankle-complex motion and stiffness in a group of athletes with a history of unilateral ankle sprain.

Arthrometric measurement of ankle-complex motion: normative values.

Context: Valid and reliable measurements of ankle-complex motion have been reported using the Hollis Ankle Arthrometer. No published normative data of ankle-complex motion obtained from ankle arthrometry are available for use as a reference for clinical decision making.

Objective: To describe the distribution variables of ankle-complex motion in uninjured ankles and to establish normative reference values for use in research and to assist in clinical decision making.

Application of generalizability theory in estimating the reliability of ankle-complex laxity measurement.

Context: Generalizability theory is an appropriate method for determining the reliability of measurements obtained across more than a single facet. In the clinical and research settings, ankle-complex laxity assessment may be performed using different examiners and multiple trials.

Objective: To determine the reliability of ankle-complex laxity measurements across different examiners and multiple trials using generalizability theory.

Knee and ankle position, anterior drawer laxity, and stiffness of the ankle complex.

Context: Anterior drawer testing of the ankle is commonly used to diagnose lateral ligamentous instability. Our hypothesis was that changing knee and ankle positions would change the stability of the ankle complex during anterior drawer testing.

Objectives: To assess the effects of knee and ankle position on anterior drawer laxity and stiffness of the ankle complex.

The effects of repetitive overhead throwing on shoulder rotator isokinetic work-fatigue.

Background: Muscle strength and endurance of the shoulder rotators is important for overhead throwing performance and dynamic glenohumeral stability. Baseball pitching is distinguished as an intermittent activity with explosive, high intensity muscle contractions separated by periods of rest. Rotator cuff muscle performance could acutely decrease due to fatigue associated with bouts of throwing.

Collegiate year of eligibility, sex, and sports achievement motivation.

The relations among year of eligibility, sex, and achievement motivation were investigated with 88 athletes representing three levels of collegiate eligibility (Year 1, Year 2/3, and Year 4) by sex. Participants were given Achievement Motivation subscales for Sporting Environments (approach-success practice, approach-success competition, failure-avoidance practice, failure-avoidance competition). A 3 x 2 analysis of variance showed significant main effects for year of eligibility and sex, and an interaction for age x sex for the failure-avoidance competition scores.

The relationships between instrumented measurements of ankle and knee ligamentous laxity and generalized joint laxity.

Aim: The purpose of this study was to evaluate whether lower extremity joint laxity is a function of a particular joint and/or a generalizable characteristic (trait) of the person. Validated instrumented measurements of ankle and knee joint-specific laxity in the same individual were correlated to determine whether a relationship exists. In addition, ankle and knee joint-specific laxity were correlated with generalized joint laxity using the modified Beighton mobility index.

Reliability and effects of arm dominance on upper extremity isokinetic force, work, and power using the closed chain rider system.

Objective: The purpose of our study was to assess the reliability of the Closed Chain Rider System between exercise sessions and to determine the effects of arm dominance using muscle force, work, and power measures during closed chain chest-press exercise.

Design And Setting: Sitting subjects underwent identical testing on 2 occasions and performed 5 reciprocal chest-press movements at speeds of 51 and 76 cm/s.

Subjects: Thirty-eight healthy college students.

Effects of specific versus variable practice on the retention and transfer of a continuous motor skill.

The effects of specific versus variable practice on retention and transfer was investigated. 30 participants were randomly assigned to one of three practice conditions. The variable speed group practiced on a pursuit rotor task at three different speeds (60, 45, 30 rpm) which were randomly distributed but equal in number for 30 10-sec.

Sex and competitive status in ankle inversion-eversion range of motion of college students.

The effects of sex and competitive status (athlete vs nonathlete) on ankle inversion-eversion range of motion was investigated. 62 collegiate athletes and 36 collegiate nonathletes, both male and female, were tested. Analysis of variance showed significant (p<.

Chondrocyte viability in refrigerated osteochondral allografts used for transplantation within the knee.

Purpose: To evaluate cell viability and matrix characteristics of refrigerated osteochondral allografts implanted up to 44 days after harvest.

Methods: Sixteen refrigerated allografts underwent histologic and ultrastructural examination and fluorescence excitation analysis prior to implantation. The average size of the graft implanted was 6.

Upper and lower body strength in relation to ball speed during a serve by male collegiate tennis players.

The relation of leg, shoulder, and grip strength to ball speed in the tennis serve was investigated. For 15 collegiate male tennis players, leg and shoulder strength were measured using a Lido Active isokinetic dynamometer, grip strength with a handgrip dynamometer, and ball speed with a radar gun. Regression analysis showed no significant (p<.

Assessment of Ankle-Subtalar-Joint-Complex Laxity Using an Instrumented Ankle Arthrometer: An Experimental Cadaveric Investigation.

OBJECTIVE: To show the relationship between direct measurements of tibial-calcaneal bone motion and instrumented measurements of ankle-subtalar-joint-complex laxity using a portable ankle arthrometer; to assess within and between-tester measurement reliability; and to determine if the ankle arthrometer can detect increased mechanical laxity of the ankle-subtalar-joint-complex after simulated injury of the lateral ankle ligaments. DESIGN AND SETTING: We used linear regression analysis to examine the relationship between direct measurements of tibial-calcaneal bone motion and instrumented measurements of ankle-subtalar-joint-complex laxity. An intraclass correlation coefficient (2,1) was calculated to determine intratester and intertester reliability for instrumented measurements of ankle-subtalar-joint-complex laxity.

Radiographic findings associated with symptomatic rotator cuff tears.

This study compared shoulder radiographs of patients with a documented rotator cuff tear with those of asymptomatic age-matched controls. Radiographs of 40 subjects with documented rotator cuff tears were evaluated along with similar films of 84 asymptomatic age-matched controls. Three radiographs were taken of each shoulder: (1) acromioclavicular joint view, (2) anterior-posterior view with 30 degrees of external rotation, and (3) supraspinatus outlet view.

Upper and lower body strength in relation to underhand pitching speed by experienced and inexperienced pitchers.

The relation of legs, arms, shoulders, and grip strength with underhand pitching speed of experienced and inexperienced female pitchers was investigated. For 16 experienced female underhand pitchers and 16 inexperienced women with no softball experience (control group) leg and arm strength were measured using a Hydrafitness exercise machine. Grip strength was measured with a handgrip dynamometer.

The relationship of age, gender, and degenerative changes observed on radiographs of the shoulder in asymptomatic individuals.

Radiographs of the shoulders of 84 asymptomatic individuals aged between 40 and 83 years were evaluated to determine changes in 23 specific areas. Two fellowship-trained orthopaedic radiologists graded each area on a scale of 0 to II (normal 0, mild changes I, advanced changes II). Logistic regression analysis indicated age to be a significant predictor of change (p < 0.

Measurement of upper and lower body strength and its relationship to underhand pitching speed.

This study investigated the possible relationship for legs, arms, shoulders, and grip strength with underhand throwing speed. 40 female subjects had their legs, arms, and shoulder strength measured using a multipurpose exercise machine for assessing resistive force. Grip strength was measured using a handgrip dynamometer.

Instrumented measurement of anteroposterior and inversion-eversion laxity of the normal ankle joint complex.

Manual examination is the most common method for the evaluation of ankle anteroposterior (AP) and inversion-eversion (I-E) laxity. Objective assessment data of normal ankle laxity must be provided before comparison with an injured ankle can be made. The purpose of this study was to compare AP translation and I-E rotation at three force loads between dominant and nondominant ankles and to assess the test-retest reliability of a portable arthrometer in obtaining these measurements.

Isotonic preload versus isokinetic knee extension resistance training.

To examine training (3 d.wk-1 for 6 wk) differences using active robotic isotonic and isokinetic concentric knee extension resistance on full range of motion (ROM) (90 degrees to 0 degree of flexion) strength development and power, 22 men and 10 women were randomly assigned to either an isotonic, isokinetic, or control group. The isotonic group exercised using a preload resistance that was initially set at 25% of peak isometric torque and then increased 5 N.

Effects of isokinetic velocity spectrum exercise on average power and total work.

In this study we compared the influence that the order of the performance of different velocity exercise progressions has on average muscle power and total work production during a velocity spectrum isokinetic training session. Twenty-two college students were assigned randomly to four exercise trials, each containing an isokinetic exercise training session involving dominant knee extensors and flexors. Each exercise trial consisted of two sets of ten repetitions at speeds of 30 degrees , 90 degrees , 150 degrees , and 210 degrees /sec.

Effects of blocked versus random practice by mentally retarded subjects on learning a novel skill.

The purpose of this study was to assess the effects of different practice conditions on mentally retarded subjects learning a novel task. 20 subjects with a mean IQ of 51.82 were randomly assigned to one of two practice conditions.

High-frequency electrostimulation hearing after mastoidectomy.

This study was undertaken to measure the degree of high-frequency sensorineural hearing loss following mastoid surgery. Twenty-five patients undergoing mastoidectomy procedures were tested preoperatively, less than 2 days postoperatively, and at 30 days postoperatively using the Tonndorf Audimax 500 high-frequency audiometer. Electrostimulation thresholds in 1-kHz intervals, from 1 to 20 kHz, were measured, and the highest detectable frequency was determined to within 0.