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T D Cook

Publications and source records attributed to T D Cook.

25 records · Page 2Linked to original sources
PubMedDate not supplied

The effects of extended play on professional baseball pitchers.

The purpose of this study was to investigate kinematic and kinetic changes as a result of extended play in baseball pitching. Seven major league baseball pitchers were videotaped with high-speed (120 Hz) cameras during multiple innings of the same game. For each athlete, two fastballs (one thrown during the initial inning of play and one from the final inning) were chosen for analysis. Twenty-one physical landmarks were manually digitized from the video data. Kinematic and kinetic parameters were subsequently calculated relative to four phases of the pitching motion: windup, cocking, acceleration, and follow-through. Paired t-tests revealed that seven parameters changed significantly between early and late innings. These included decreases in maximum external rotation of the shoulder, knee angle at ball release, ball velocity, maximum distraction force at both the shoulder and elbow, and horizontal adduction torque at both release and its maximum value. Ultimately, a decline in performance was evident by a 2 m/s (5 mph) drop in ball speed. It is unclear whether the kinematic and kinetic changes occurred because of fatigue or if protective mechanisms were adopted.

Adult↗
PubMedDate not supplied

Relationships between throwing mechanics and shoulder distraction in professional baseball pitchers.

The extreme forces and torques and the high speeds and excessive ranges of motion of baseball pitching place tremendous stress on the soft tissues of the throwing shoulder. Little is known about the relationship between pitching mechanics and shoulder joint stress, especially in professional athletes. The purpose of this study was to quantify joint loads and kinematic parameters of pitching mechanics at the major league level and to study their relationships. Three-dimensional, high-speed video data were collected on 40 professional pitchers during the 1998 Cactus League spring training. A clinically significant distraction force was calculated at the shoulder joint, which reached an average peak value of 947 +/- 162 N (108% +/- 16% body weight). Descriptive statistics and a multiple linear regression analysis were used to relate shoulder distraction to kinematic and kinetic parameters of pitching mechanics. This study was undertaken not only to investigate the peak forces and torques on the shoulder, but also to identify potential areas of intervention that might prevent throwing injuries. Knowledge of joint ranges of motion, angular velocities, and joint-reaction forces can provide a scientific basis for improved preventive and rehabilitative protocols for baseball pitchers.

Adult↗
PubMedDate not supplied

Optimizing dynamic T2* MR imaging for measurement of cerebral blood flow using infusions for cerebral blood volume.

We describe an approach to measuring cerebral blood flow (CBF) based on independent measurements of cerebral blood volume (CBV) and mean transit time (MTT) with calculation of CBF by using the central volume theorem: CBF = CBV / MTT. This permits optimization of the individual acquisitions and analyses. In particular, measurement of CBV during contrast infusion, rather than simultaneously with MTT from a single bolus, yields values more consistent with those of other methods.

Adult↗
PubMedDate not supplied

A meta-analytic analysis of effects of psychoeducational interventions on length of postsurgical hospital stay.

Forty-nine studies of the relationships between brief psychoeducational interventions and the length of postsurgical hospitalization are reviewed using meta-analysis. Results show that interventions reduce hospital stay about 1 1/4 days and that reduction does not depend on whether the studies were published or not, whether the discharging physician was aware of the patient's experimental condition, or whether studies were lacking in internal validity. The interventions' effects on length of hospital stay are distinctly smaller in more recent studies, with analysis suggesting current treatments incorporate fewer components than earlier studies. Lesser effects are also found when the treatment is compared with a placebo-treatment group rather than a usual-care control group. This may be because placebo procedures often include educational and socially supportive components that constitute part of the psychoeducational interventions under review. The present study, providing a more stable foundation than previously available, supports the belief that brief psychoeducational interventions may be cost effective with surgical patients of many kinds because the length of hospital stay is reduced.

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