Prevalence and Impact of Left-Handedness in Neurosurgery

Highlights

• Of surveyed neurosurgeons, 17% were LH (n = 1482).

• LH neurosurgeons are more likely to report operative ambidexterity.

• Attitudes toward training LH students vary by trainer handedness.

• There is evidence of adaptation in LH neurosurgeons over time.

Background

Approximately 10%–13% of the population is left-handed (LH), and certain professions have varied representation of LH individuals. LH surgeons must overcome unique difficulties owing to the right-handed (RH) operative environment. This study assesses prevalence and impact of left-handedness on training and operative experience of neurosurgeons.

Methods

An e-mail survey was designed and sent to 5109 U.S. neurosurgeons and neurosurgical trainees. The survey was completed by 1482 responders (29.0% response rate).

Results

Of respondents, 252 (17.0%) reported being LH. LH neurosurgeons were more likely than RH neurosurgeons to report ambidexterity in the operating room (36.5% vs. 13.3%, P < 0.001). During neurosurgical training, 23.5% of RH trainers addressed LH-specific issues compared with 44.7% of LH trainers. LH trainers were more likely to describe LH trainees as having greater technical ability (18.9%). Most trainers reported equal comfort teaching LH and RH trainees. LH trainees reported difficulties with RH surgical tools (42.7%) and a tendency to alter handedness for surgery (62.7%). The impact of these areas lessens in LH attendings (27.8% and 39.9%, respectively). Most LH neurosurgeons denied specific training for left-handedness and access to LH-specific tools, and 24.0% of LH trainees reported feeling disadvantaged owing to their handedness.

Conclusions

LH neurosurgeons may be overrepresented in neurosurgery, yet handedness is rarely addressed in neurosurgical training. Despite this, there is evidence of some degree of adaptation through training. There may be some benefit from recognizing differences in handedness in the operating room and attempting to give access for LH-specific mentorship during training.

Introduction

It is estimated that 10%–13% of the population is left-handed (LH).1, 2, 3 Handedness is typically defined by an individual's preference to use 1 hand in unilateral tasks or the increased dexterity of 1 hand compared with the other.⁴ Because many daily tasks are designed for right-handed (RH) people, LH individuals are inherently expected to adapt to a RH world. Activities such as typing, writing, cutting with scissors, using a can opener, and driving a car all necessitate LH individuals to “adjust” by using the nondominant hand to perform the task.

Possibly as a of result of this adaptation, LH individuals show a greater degree of ambidexterity,⁵ a trait that may prove advantageous compared with RH individuals. This advantage may be evidenced by the relatively larger prevalence of LH individuals among professional boxers⁶ and baseball,⁷ hockey,⁸ tennis,⁹ table tennis,² cricket,¹⁰ and handball¹¹ players. In addition, students in music and visual arts¹² and professionals in architecture12, 13 and law¹³ have an overrepresentation of LH individuals.

Some degree of ambidexterity is essential for the training and practice of neurosurgery. Challenges in training and practice of surgery among LH surgeons have been previously addressed,14, 15 with the notion that LH surgeons are considered less technically skilled than their RH counterparts.15, 16, 17, 18 In the training environment, modeling a RH mentor can prove difficult for a LH trainee.¹⁹ A left-sided or right-sided aneurysm or brain tumor may be more or less challenging to the LH neurosurgeon based on the technical nuances associated with using the dominant hand. Working in tandem across the operating table in open or minimally invasive spine surgery may also prove problematic given the lack of “mirror” symmetry in assisting or observation.

Although handedness prevalence of physicians and medical students has been previously studied in small subsets,13, 18, 19, 20 there is a paucity of information on the prevalence of LH neurosurgeons. The challenges in the practice and training of LH neurosurgeons as perceived by practitioners, trainees, and trainers have not been previously studied. We performed a national survey of neurosurgeons in training and practice. Our objective was to better understand the challenges encountered by LH neurosurgeons during training and practice. We hypothesized that the experience of LH neurosurgeons may be particularly influenced by the training and practice of neurosurgery, which is likely biased toward RH neurosurgeons. We also sought to identify the prevalence of left-handedness within the field of neurosurgery.