When Will I Know Which Hand She Will Use?

Patient Presentation
A 3-year-old female came to clinic for her health supervision visit.
During the visit she drew on the chalkboard a circle with two lines sticking out of it representing limbs. When she was asked to draw her dog, she switched the chalk to the other hand and continued drawing. Her mother noted that the preschooler switched hands often while drawing, and wanted to know when she would develop a hand dominance. The pertinent physical exam showed a healthy female with growth parameters in the 75-90%. Her examination was normal including her neurological examination. The diagnosis of a healthy preschooler was made. The resident wasn’t entirely sure when children develop hand dominance but told the mother that he was sure that it was common at her age to use both hands with writing but by around kindergarten most children had developed a hand dominance.

Discussion
Most children and adults do develop a hand dominance. Right-handedness is more common (70-90%) than left-handedness (8-10%). In many western cultures, right-handedness was/is considered the “correct” or “right” hand to use, and left-handedness was unlucky, inauspicious or frankly evil. The word “sinister,” meaning left-sided, derives from various sources as early as the 15th century. There are numerous instances of left-handedness being associated with wickedness. For example, the devil is often portrayed as left-handed, and people throw salt over their left shoulder to ward off the evil spirits that dwell there.

Many left-handed people report being able to use their right hand very well for certain tasks because of needing to adapt to tools which are usually designed for right-handed people such as scissors, golf clubs, etc. Some people are also mix-handed, where they perform some tasks with one hand and other tasks with the opposite hand. Some people have true ambidexterity where they can perform tasks equally well with both hands.

Learning Point
Children begin to develop hand dominance around 2-3 years and this should be well developed by age 5 and fully developed by age 6. Use of a dominant hand before 2-3 years time may occur because of abnormal fine motor development. It could also be the result of intracranial injury or injury to a limb with appropriate compensation by the other limb. Development of hand dominance after 6 years, again may indicate abnormal development. Referral to an occupational therapist may be indicated, and referral indications can be reviewed here.

Questions for Further Discussion
1. When do children develop eye dominance?
2. Do people develop right- or left-footedness?
3. What are the potential advantages of right- or left-handedness?
4. What Gessel figures should a 3 year old be able to draw? 4 year old?
5. Can a left-handed dominance be changed after it develops?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for this topic: Toddler Development

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

Sinister. Merriam-Webster Dictionary. Available from the Internet at http://www.merriam-webster.com/dictionary/sinister (rev. 2011, cited 2/2/11)

Wilms Floet AM, Maldonado-Duran JM, Motor Skills Disorder. eMedicine.
Available from the Internet at http://emedicine.medscape.com/article/915251-overview (rev. 1/22/10, cited 2/2/11).

ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effectively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients’ is gathered.
    5. Patients and their families are counseled and educated.
    8. Health care services aimed at preventing health problems or maintaining health are provided.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.

    Author

    Donna M. D’Alessandro, MD
    Professor of Pediatrics, University of Iowa Children’s Hospital