Certainly in earlier days, sinistrality was a problem for children learning to write. An eminent sinister-handed Dallas plastic surgeon reported: “In parochial summer school the nuns were determined to change me and actually tied my left hand behind my back. The result of this action was tremendous tenacity and endurance! … We write left to right and smear our fresh ink across the page.” He added: “Numerous theories throughout history have claimed that being left-handed causes developmental and immune disorders. It has also been said that left-handers die younger, have more diseases and are even considered inept. None of these theories have been proven” (1). Remember that Ben Franklin had a miserable left-handed childhood and as an adult wrote “A petition to those who have the Superintendency of Education” in which he recorded, “If by chance I touched a pencil, a pen, or a needle I was bitterly rebuked; and more than once I have been beaten for being awkward and wanting a graceful manner.” He ended his epistle by signing it, “I am with profound respect, Sirs, your obedient servant. THE LEFT HAND” (2). It is generally thought that there is an increased incidence of injuries in left-handed people because we live in a right-handed world and have done so for many centuries. Some would have us believe we are right-handed because our early hominid ancestors are thought to have coupled early speech to muscle actions already lateralized to our brain's left hemisphere at an earlier point in hominid evolution; I tend to prefer the concept of Calvin (3), who suggested that “selective pressures on infant carrying females throwing missiles when hunting led to preferential right-handedness; they carried their infant on the left side of their body where the heartbeat is stronger and thereby keeping the infant more secure and quiet.” Today the environment of our world strongly favors the right-handed majority. Adusumilli et al (4) in their paper published in 2004 catalogued some of the hazards facing the sinister handed. “Although they are considered to be more intellectual, and artistic, studies have documented that they are more prone to unintentional injuries, head trauma, motor vehicle accidents, and increased sports injuries. Left-handed industrial workers are 5 times more prone to finger amputations than right-handed workers.” Coren (5) in 1989 enumerated many of the problems left-handers are faced with: “Everyday implements such as gearshifts, scissors, and can openers are biased toward right-handed use.” Even in their homes the sinistrals are forced to accommodate to everyday items such as spiralbound notebooks with the spiral on the “wrong” side, electric irons with the power cable protruding on the right, corkscrews, light bulbs, garden secateurs, and potato peelers. On entering a building, we right-handers instinctively turn to our right; intelligent shopkeepers know this and display attractive, and usually expensive, goods on the right. Even traffic patterns are designed to utilize this right-turning bias. Nine different professional groups were studied by Schachter and Ransil (6) in 1996 on handedness distributions in approximately equal numbers of accountants, architects, dentists, lawyers, librarians, mathematicians, orthodontists, orthopaedic surgeons, and psychiatrists. Three hundred people from each profession were asked, by mail, their age, sex, and whether they considered themselves right- or left-handed or ambidextrous. Of the 2007 questionnaires mailed, 1196 (44%) were returned. The data regarding their verbal skills, visuospatial skills, bimanual fine motor skills, and mathematical skills were submitted to various computations in which the available responses were always left, usually left, no preference, usually right, and always right. From the average laterality scores, it appears that orthopaedic surgeons, librarians, and mathematicians are mostly right-handed and that lawyers and architects are either the least right-handed or the most left-handed. The differences between mathematicians/librarians and orthodontists/dentists were neither statistically nor clinically significant. Any influence of sex was considered inconclusive because of the 9-to-1 disproportion of male to female responders. So how do left-handed surgeons and orthodontists get along at work? In general, just like their right-handed colleagues, but there seems to be a longer learning curve. In their paper “Left-handed surgeons: are they left out?” Adusumilli et al (4) surveyed 68 surgeons in the New York City area, of whom only 5 were female; 31% were ambidextrous and 69% were left-handed. Among the left-handed, they found considerable difficulty using long vascular needle holders, heavy hemostatic clamps, and right-handed scissors. Twenty-eight percent felt prone to needle sticks and other hazards. Operations such as cholecystectomy, right hemicolectomy, pelvic operations, and procedures around the gastroesophageal junction were difficult to learn when standing on the right side of the operating table.
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