Outcomes and complications associated with malar onlays: literature review and case series of 119 implants.

Alloplastic malar onlays have been used by surgeons to correct or enhance the midfacial skeleton for over 40 years. Case series have shown respectable results using different alloplastic materials in various maxillofacial subsites. However, these articles include small numbers of patients with limited follow up. We present a literature review specifically concentrating on porous polyethylene (Medpor, Stryker) and polyethyl ether ketone (PEEK) malar onlays. We illustrate the technique used by a single oral and maxillofacial surgeon for placement of 119 implants in 61 patients over a 14-year period, and show the results of this work with long-term follow up. A complication rate of 2.5% in this cohort was reported, with follow up of three years, demonstrating that this technique for midfacial correction is successful in both the short and the long term.

The development of sport-specific planning, rehearsal, and updating of plans during defensive youth baseball game performance.

The development of planning, rehearsal, and updating of defensive baseball plans was investigated in this study. Thirty-two male shortstops (seven 8-year-olds, eight 10-year-olds, nine 12-year-olds, and eight high school youths) were trained to perform a concurrent talk-aloud procedure before a pitch was thrown to the opposing batter. Participants completed a 40-item baseball knowledge test. Players' ages were highly correlated with their baseball knowledge (omega 2 = .88). Any subsequent age differences reflect differences in players' knowledge. Shortstops ages 12 years or younger frequently did not produce: (a) advanced defensive plans, (b) active rehearsal of plans, or (c) updating of defensive plans. When the young players did produce these strategies, the quality was generally poor; High school shortstops produced all these sport-specific strategies with advanced quality. The younger players' production and quality deficits in sport-specific strategy use may be related to their lack of a highly developed knowledge representation and the types of practice and game experiences they have had playing baseball.

Knowledge representation and problem solution in expert and novice youth baseball players.

The purpose of this study was to examine differences in knowledge representation and problem solutions in expert and novice youth baseball players. Ninety-four players in two age divisions, 7-8 years of age and 9-10 years of age, were assigned to three levels of expertise: high; average; and low skilled. Each subject participated in an interview session to elicit knowledge representation and solutions to five different defensive game situations. Interviews were transcribed and analyzed for content, solution to the problem, errors in problem solution, and qualitative trends. The frequency of advanced solutions to each of the five situations were analyzed in separate chi-square tests for age and expertise. Differences among the levels of expertise were found for the accuracy of solutions to three complex situations. Age was significant for only one situation. Patterns of knowledge content accessed during advanced and less advanced responses indicated both experts and novices were in a beginning stage of developing baseball knowledge structures. Errors in problem solutions indicated children had difficulty monitoring critical conditions and making correct inferences. Players' and teammates' ability to execute baseball skills seemed to influence the content and structure of tactical knowledge accessed during problem solution.

Expert-novice differences in cognitive and skill execution components of youth baseball performance.

Previous research has shown that experts exhibit superior response selection and skill execution during performance in youth sport. The purpose of this study was to examine differences in cognitive and skill execution components of game performance in young baseball players (N = 159) with varying levels of expertise. Three levels of expertise (low-, average-, and high-skilled players) were identified at each age level (7, 8, 9, and 10 years of age). Game performance was videotaped, and measures of skill execution (throwing accuracy, throwing force, fielding, catching, batting average, and batting contact) and cognitive components (positioning, decisions) were developed from observational analysis. The results indicated that baseball skill execution during game play maximally discriminated expertise levels.

Somatic comparisons of urban and rural Russian boys, ages 6, 9, and 15 years, living in St. Petersburg and surrounding areas.

Somatic data were collected during September 1991 on 280 males, ages 6, 9, and 15 years, residing in urban St. Petersburg, Russia, and in rural regions surrounding the city. Comparisons are made between urban and rural groups for measures of body size and form, skinfold thicknesses, body mass index (BMI), and estimated arm muscle area (ARM). The data were analyzed in 2 (urban-rural) × 3 (age) analyses of variance, with an alpha level of P < 0.05. Age differences were evident for all measurements. A significant main effect for urban-rural was found for stature, lower limb height, and calf girth; differences approached significance (P < 0.07) for body weight and sitting height. Urban children were larger than rural children in stature, sitting height, lower limb height, calf girth, and body weight. The interaction was nonsignificant. Urban and rural boys did not differ on measures of body form. Similar means were obtained for the sum of skinfolds, the BMI, and ARM in urban and rural boys. Compared with data collected more than a century ago, present-day 15-year-olds are 22 cm taller. It has often been suggested that living in an urban environment provides greater access to the amenities of life than living in a rural area. Although these amenities are difficult to observe differences do exist and the secular trend continues. © 1994 Wiley-Liss, Inc.

Effects of DDAVP on movement planning and execution processes in the healthy elderly.

Effects of DDAVP on speed and consistency of planning and executing simple and complex movements in healthy older adults were studied. A simple reaction time (SRT) task, a single-plane movement task, and two tasks involving multiplane movements of distal upper extremities were performed with and/or without a 0.6 ml intranasal dose (60 micrograms) of DDAVP or placebo. Results indicated that DDAVP had no significant effect on speed or consistency of SRT processes, or the speed with which simple or complex movements were planned or executed. There was also no effect on retention of motor responses.

References for motor tasks--gender differences across age in motor performance: a meta-analysis.

In 1985 we published a meta-analysis of gender differences across age in motor performance in Psychological Bulletin, but it did not include an indexing of each motor task to the references from which it was obtained. This paper provides a table listing the 20 motor tasks and the references from which data for each task were taken. The range of tasks was from fundamental movements (e.g., catching, jumping, running, throwing) to motor fitness (e.g., agility, arm hang, balance, grip strength) to perceptual-motor abilities (e.g., anticipation timing, fine eye-motor coordination, pursuit-rotor tracking, reaction time). The arm hang was represented in the fewest papers (n = 2) while the dash and long jump were most frequently referenced (n = 21).