The Right Way to Teach Left-Handed Residents: Strategies for Training by Right Handers

The Right Way to Teach Left-Handed Residents: Strategies for Training by Right Handers

ORIGINAL REPORTS The Right Way to Teach Left-Handed Residents: Strategies for Training by Right Handers Nikhil K. Prasad, MB, ChB, Charlotte Kvasnovs...

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ORIGINAL REPORTS

The Right Way to Teach Left-Handed Residents: Strategies for Training by Right Handers Nikhil K. Prasad, MB, ChB, Charlotte Kvasnovsky, MD, PhD, Eric S. Wise, MD and Stephen M. Kavic, MD Department of Surgery, University Of Maryland Medical Center, Baltimore, Maryland PURPOSE: Left-handed (LH) residents remain underre-

presented among surgical trainees, and there are few available data on how best to train them. The challenge is amplified when pairing a LH resident with a right-handed (RH) mentor. This report provides recommendations on how to improve the training of LH surgeons in a safe and effective manner. METHODS: A comprehensive literature review was performed using different databases and search engines to identify all articles relevant to the training of LH residents. RESULTS: A total of 40 articles highlighted the challenges

for LH surgical residents and RH mentors. Our recommendations are based on the following 4 themes: identifying inherent differences in left vs. RH residents, providing guidance to RH mentors training LH residents, adapting the RH environment to the LH surgeon, and maximizing safety during training. CONCLUSION: An organized approach needs to be taken

in training the LH resident. Changes should be instituted at program-wide and national levels to ensure that the training experience of the sinistral surgical resident is optimized. C 2017 Association of Program ( J Surg Ed ]:]]]-]]]. J Directors in Surgery. Published by Elsevier Inc. All rights reserved.) KEY WORDS: functional laterality, laparoscopy, motor

skills, surgeons COMPETENCIES: Systems Based Practice, Practice Based

Learning

with being left-handed (LH). Classically, the association with the Latin “sinister” has extended to multiple idiomatic uses with negative connotations in modern English including “left behind,” “out in left field,” and “two left feet.” Left-handers must deal with a number of real-life practical concerns that favor the right-hand–dominant population. In technical fields, one might expect a significant amount of study and reflection concerning the use of hands, and handedness in particular. Within surgery, there is little mention of left-handedness. Standard surgical textbooks, such as Sabiston’s Textbook of Surgery, Schwartz’s Principles of Surgery, Greenfield’s Surgery Scientific Principles and Practice, or even The Society of American Gastroenterologists and Surgeons Manual, make no specific mention of left-handedness. The limited data that exist suggests that there may be proportional underrepresentation of LH surgeons.2,3 With this lack of information, there is potential for misattributing early delays in the technical skill acquisition of LH residents to an innate talent deficit. In fact, in a survey of LH surgeons, 10% of the surgeons themselves would feel uncomfortable if they needed surgery, and their surgeon was LH4! In this article, we review all relevant literature concerning the training of LH surgeons. Specifically, we identify the challenges in training. We also provide a list of considerations that may not be apparent to most right-handed (RH) surgeons. Lastly, and most importantly, we aim to provide strategic guidance for improvement of LH training on both individuals and programs.

INTRODUCTION

LITERATURE SEARCH

Approximately 12% of the population is left-hand dominant in the Western world.1 At times, there is a stigma associated

Two databases (OVID Medline and Pubmed) and the search engine Google Scholar were used for the literature search. The terms “left-handed,” “handedness,” “training,” “trainee,” “resident,” “surgery,” “surgeon,” and “surgical” were combined using Boolean logic to identify all relevant articles. These were then cross-referenced to identify any

Correspondence: Inquiries to Stephen M. Kavic, MD, University of Maryland School of Medicine, 29 South Greene Street, GS 631, Baltimore, MD 21201; fax: (410) 328-5919; e-mail: [email protected]

Journal of Surgical Education  & 2017 Association of Program Directors in Surgery. Published by 1931-7204/$30.00 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jsurg.2017.07.004

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missing articles. Articles not written in English were excluded.

RESULTS The literature search generated 40 articles. These were classified based on the type of article—randomized control trial, cohort study, retrospective case series, survey, or editorial. The first 3 of these categories are summarized in Table 1. We stratified our findings and recommendations into 3 categories based on the core themes that arose in literature. The major issues confronting LH trainees are listed in Table 2.

steering, and advancement. Indeed, the difficulty experienced by the RH endoscopist ostensibly led to the nowabandoned “two-person colonoscopy” technique, wherein an assistant drives the shaft while the endoscopist uses 2 hands to drive.16 To our knowledge, this apparent innate benefit to LH endoscopists has not been researched. Challenges to Mentoring

There has been a historic bias against LH surgeons, highlighted in a publication by Schott and Puttick.5 This article suggested that LH surgeons may not possess the motor skills necessary to perform surgery. Subsequent studies, however, refuted this assertion; nonetheless, the stigma of the sinistral surgeon persisted!2,3 Some studies have pointed to greater manual dexterity among RH surgeons. For instance, one showed greater ambidexterity among RH surgeons as compared to LH surgeons.6 It was also been suggested that LH surgeons tend to make more unnecessary movements and are less accurate when performing laparoscopic tasks.7,8 Many of these studies, however, were carried out on small samples of medical students or nonsurgical trainees and rarely tracked the acquisition of skills over time; moreover, the tasks may have inherently favored right-hand–dominant candidates. When assessments of dexterity have been designed to account for handedness, there does not appear to be any difference between RH and LH.2 The first step in training the left-hand–dominant resident is to recognize that inherent differences in the acquisition of psychomotor skills that may exist between RH and LH.9,10 Regardless of handedness, practice improves performance.11,12 Toward the end of training, LH surgeons may in fact have lower complication rates than RH surgeons.13 It is important not to force the LH resident to use their nondominant hand preferentially, as this may be less safe and require a greater degree of baseline skill and understanding to perform the task effectively.14 Nonetheless, we acknowledge that ambidexterity is invaluable in surgery and may be trained by strengthening exercises and simulation involving primarily the nondominant hand.15 Skills in endoscopy should, in theory, be simpler to acquire for the LH surgeon, as the left hand must balance the up-down and left-right knobs, as well as irrigation and suction, while the right hand is responsible only for torque,

Given the fact that surgical training is in essence an apprenticeship, wherein the trainee acquires skills by observation and emulation, it is essential for surgical mentors to understand the resident’s perspective and anticipate potential deficiencies in technique. Surveys show that RH surgeons are on the whole less comfortable than their sinistral counterparts in training LH residents and are more likely to judge LH residents as having less technical abilities.17 In addition, given the underrepresentation of left hand in surgery, the vast majority of trainees have never met a LH mentor in medical school or residency.18,19 The first step in effectively training the LH surgical resident is recognition and acknowledgment of their hand preference. Most residents remark that their handedness had never come up in interviews or job applications.18 Handedness is not included in American Medical College Application Service to medical school, nor in Electronic Residency Application Service to residency. The early identification of the LH trainee allows the mentor to anticipate difficulties that they might face during a case and frees the trainee from the anxiety of being judged poorly.20 Mentors should acknowledge early that LH trainees must learn to use instruments slightly differently than RH trainees. Often, the first skill acquired is cutting suture as a medical student. Using a RH scissor with the left hand will naturally push the blades slightly apart, increasing the likelihood that the LH trainee will require several attempts to cut suture. A brief primer at the beginning of internship or even a medical student clerkship could facilitate skills acquisition for simple tool-handling techniques. Given the preponderance of RH instruments, it is the authors’ opinion that LH trainees should continue to train with RH instruments. The benefit of early intentional pairing of LH residents and staff surgeons cannot be overstated. Aside from providing reassurance and empathy for difficulties experienced in adapting to system developed by and for RH surgeons, it would allow the transfer of subtleties, tips, and modifications of technique acquired through years of trial and error. The challenges of training LH residents become more apparent at certain crucial stages of a procedure. Freeman et al.21 used a modular training method to teach LH ophthalmology residents how to perform phacoemulsification. The procedure was broken up into 6 stages, and each stage was adapted such that the positioning of the patient and surgical exposure were planned in advance based on the handedness of the trainee. A similar approach to all surgical

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The Effect of Handedness on Surgical Skill Acquisition

TABLE 1. Comprehensive Literature Review for Training Left-Handed Residents Author

Year

n

Subjects

Key Points

Systematic reviews Tchantchaleishvili

2010

19

Articles

Handedness produces anxiety among trainees and mentors (Table 2) There is limited adaptation of mentoring for LH There are few programs with left-handed instruments

Randomized control trials Middleton

2013

23

Students

Playing the Nintendo Wii improves manual dexterity and surgical skills acquisition in the dominant and nondominant hand regardless of handedness.

Cohort Studies Alnassar

2016

54

Badalato

2014

10

There is no difference in the performance of surgical psychomotor tasks between LH and RH Performance of surgical skills tasks on the da Vinci robot eliminates potential deficits due to hand dominance

Lee

2013

19

Sarker

2013

34

Medical students Urology and ob/ gyn residents Medical students Residents

Park

2012

30

Nonsurgical physicians

Elneel Torgerson

2008 2007

50 36

Students Students

Canacki

2004

18

Dental students

Grantcharov

2003

25

Residents

Hanna

1997

20

Scheuneman

1985

141

Medical students Residents

Case Series Pennington

2014

160

Kim

2009

170

Mehta

2007

728

Freeman

2004

161

Gupta

2003

1

Oms

2003

1

Moloney

1994

244

Questionnaires Anderson

2016

130

Total hip replacement Cataract surgery Total knee replacement Cataract surgery Pelvic surgery Laparoscopic cholecystectomy Sliding hip screw Surgeons and residents

Journal of Surgical Education  Volume ]/Number ]  ] 2017

Students perform better if faced with tasks that are concordant with their hand preference There is an improvement in the performance of laparoscopic skills regardless of handedness Surgery with the nondominant hand is slower, more dangerous, and a higher degree of skill in the dominant hand is required to be able to perform the procedure with the nondominant hand RH are more ambidextrous RH are better at using the right-handed temporal bone drill than LH RH may perform better at manual dexterity tasks initially but both LH and RH have similar learning curves LH make more unnecessary movements than RH when performing simulated laparoscopic skills RH have less errors and better first-time accuracy than LH when performing laparoscopic simulation tasks LH have higher scores than RH in neuropsychological tests of tactile-spatial abilities RH and LH surgeons perform better total hip replacement when operating on the dominant side LH residents have a lower incidence of posterior capsule tear and vitreous loss than RH RH surgeons have worse outcomes when performing total knee replacement on the nondominant side LH can safely be trained to perform cataract surgery using an adapted, staged training model Ambidexterity and endurance can be enhanced through simulation training and handwriting for extended periods of time with the nondominant hand Situs inversus offers a rare advantage to the LH surgeon over the RH surgeon—allowing them to dissect the gallbladder with their left hand There is a higher technical failure rate for the RH surgeon working on the left hip RH surgeons have greater difficulty than LH surgeons when training LH residents RH surgeons are more likely to report that LH residents have less technical ability

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TABLE 1 (continued) Author

Year

n

Subjects

Key Points

Kapoor

2016

91

Mbirimtengerenj

2012

1966

Positioning is a key factor in being able to perform dental procedures comfortably as an LH resident There is no difference in the incidence of needlestick injuries among RH and LH healthcare workers

Damore

2009

778

Dental residents Taiwanese healthcare workers Physicians

Lieske

2008

9

Makay

2008

194

Chief residents Surgeons

Adusumilli

2004

68

Surgeons

Henderson

1996

70

Schott

1995

36

Dental students Surgeons

procedures might enhance the training experience for mentor and protégé and ensure a much more efficient case for the patient. It is important to note that one should not try to force someone who is early on in their training to use their nondominant hand, as this has been shown to be slower and potentially more dangerous.14 Adapting the Dextral Environment to the Sinistral Surgeon Most aspects of any operation – from the positioning of the patient, the surgical techniques, and the instruments used – have traditionally favored the RH resident. As such, initial difficulties encountered by LH residents may not represent an inherent lack of skill or talent, but the initial grapplings with an environment that is designed from a mirrored perspective to their own. There are certain fundamental procedures that pose a unique challenge to perform or assist in when LH, notably, the laparoscopic cholecystectomy.22 Unfortunately, for LH trainees, this is the single most common procedure performed in surgical residency. It should be noted that the TABLE 2. Major Training Issues for Left-Handed Residents (Adapted and Expanded With Permission From Tchantchaleishvili and Myers20) No acknowledgment of differences Anxiety about laterality Pressure to adapt and change to right-handed style Difficulty handling instruments Open right-handed scissors Laparoscopic instruments Endoscopes Procedural differences Disadvantage of right-sided procedures (cholecystectomy) Potential advantage of left-sided rocedures (splenectomy) 4

LH physicians reported greater difficulty in the acquisition of procedural skills While in training, the residents did not have opportunities to meet left-handed faculty Technical modifications to laparoscopic surgery are warranted for left-handed surgeons 97% of LH surgeons never had an LH mentor 87% of surgical residency programs did not provide LH instruments 17% of orthodontists are left handed Not a single responder to the survey was left-handed

difficulties are not inherent to the operation, rather that the conventional steps have been refined over the past 2 decades by RH surgeons. Any dissection will have aspects that may favor both RH and LH. The orthopedic literature actually shows worse outcomes when RH surgeons operate on the patient’s left hip or knee in terms of pain and technical failure.23-25 Lastly, most surgical equipment is designed with right handers in mind. This issue has been raised in cardiac26 and ear, nose, and throat surgery.27 The first step in optimizing the training environment is identification of the surgical resident’s handedness at the time of patient positioning.21,28,29 It is also important at this stage to make the operating room staff aware. There have been several articles in the past few years describing optimization of surgical technique to favor the LH surgeon when performing cardiac26,30,31 and laparoscopic procedures.32-34 In coming years, coincident with emergence and advancement of ever more complex minimally invasive techniques, interest in optimization of facilitation of the LH surgeon will become increasingly critical. In the meantime, it is important to note that adaptations must be made to how left handers use common instruments such as needle-drivers (requiring hooking of the thumb to release the ratchet) and scissors (with pronation rather than supination to approximate the blades). An alternative is to provide a set of LH instruments to LH trainees.26 We do not recommend this given that availability of these instruments is not widespread.

SAFETY Risks to the Patient Use of the nondominant hand to perform critical tasks may increase the procedural risks to the patient. This seems Journal of Surgical Education  Volume ]/Number ]  ] 2017

intuitive and has not been rigorously studied in surgical patients. Interestingly, once an LH trainee has adapted to RH instruments, it may be difficult to switch back to the more natural LH instruments. In this way, the continuity of using the same instruments repeatedly may trump the benefits of using handed-appropriate action only occasionally. Risks to the Trainee Operating with RH mentors in mirror image across the table creates some inherent conflict. The LH trainee will reach with the nondominant hand for the same position as the dominant hand of the mentor. This could, in theory, increase the potential for needlestick and similar injuries. This may be more of an issue when 2 opposite-handed surgeons are closing a large wound simultaneously or brooking a stoma. The lone retrospective study to examine needlestick injuries, performed in Taiwan, did not show a difference in rates based on handedness.35 Conversely, the mirroring of perspective may in fact be useful when demonstrating a technique to a surgical trainee.

STRATEGIES FOR IMPROVEMENT We offer several strategies for standardization and optimization of training LH residents. These can be implemented at a local level (Table 3), or on a national or international scale (Table 4). On a program level, LH trainees should be identified early. Any program can ask the question of handedness during the interview process. If this may judge to carry the semblance of impropriety, programs may wait and ask during the orientation process to the institution. Once identified, LH trainees can be paired with LH mentors. This can signal acceptance of all types of handedness, and consequently alleviate trainee anxiety. It is a relatively simple matter to assemble and publish a list of LH faculty and trainees. Another simple intervention involves the operating room staff. Operating room “preference cards” can be prominently marked with dominant-hand notation. This task is made all the more feasible in the era of the electronic medical record. TABLE 3. Strategies to Optimize Training at the Program Level Early identification of left-handed residents Direct question at orientation Pairing with left-handed role models and mentors Encourage ambidextrous exercises Obtain and make available standard sets of left-handed instruments Publish a list of left-handed surgeons and trainees Update operating room “preference cards” with dominanthand notation Journal of Surgical Education  Volume ]/Number ]  ] 2017

TABLE 4. Large-Scale Considerations to Help Improve Training for Left-Handed Surgeons Increase awareness and openly discuss handedness Include discussion of handedness in standard textbooks Include handedness on Electronic Residency Application Service application Encourage research in handedness and skills acquisition Obtain help from experts in other fields Consider parallel techniques (mirror image training) Standardization of technique as with LH writing

Last, medical centers can obtain standard sets of LH instruments. On a larger scale, it is important to raise awareness of the population of LH surgeons. Handedness could easily be added to Electronic Residency Application Service applications for residency. Although in principle this could be used as screening criteria, it could and should increase program awareness and optimize early efforts at LH education. If this variable were to be added, it would be optional in order to prevent trainees from feeling obligated to justify their natural hand preference. Handedness also deserves a place in the next editions of standard surgical textbooks. Research should also be encouraged into handedness. In a technical specialty such as surgery, the lack of attention to this topic is surprising. We should seek inspiration from other fields, be it learning graphic arts or even musical instruments, where others have already developed some techniques for dealing with handedness. Ultimately, the information that those strategies provide should benefit all trainees, regardless of handedness.

SUMMARY LH surgeons remain underrepresented in the surgical specialties. Although the introduction of novel technologies such as robotic surgery may eliminate the effect of handedness,36 the issue clearly requires more attention in the coming years. On the whole, there does not appear to be any overt bias against LH surgeons, either from patients or other surgeons; although it is interesting to note that as many as 10% of left-hand–dominant surgeons would not want to be operated on by a LH colleague.4 More work is need to improve the visibility of LH surgeons and produce a standardized approach to training LH residents.

REFERENCES 1. Handedness statistics. Available at: 〈Rightleftright

wrong.com〉. http://rightleftrightwrong.com/statistics. html. Accessed 13.02.17. 2. Lee JY, Mucksavage P, McDougall EM. Surgical skills

acquisition among left-handed trainees-true inferiority or unfair assessment: a preliminary study. J Surg Educ. 2013;70(2):237-242. 5

3. Alnassar S, Alrashoudi AN, Alaqeel M, et al. Clinical

psychomotor skills among left and right handed medical students: are the left-handed medical students left out? BMC Med Educ. 2016;16:97.

Williams CB. Cotton and Williams0 Practical Gastrointestinal Endoscopy. Oxford: John Wiley & Sons; 2013.

4. Dobson R. The loneliness of the left handed surgeon.

17. Anderson M, Carballo E, Hughes D, Behrer C, Reddy

Br Med J. 2004;330(7481):10. 5. Schott J, Puttick M. Handedness among surgeons. Br

Med J. 1995;310(6981):739. 6. Elneel FHF, Carter F, Tang B, Cuschieri A. Extent of

innate dexterity and ambidexterity across handedness and gender: implications for training in laparoscopic surgery. Surg Endosc. 2008;22(1):31-37. 7. Hanna GB, Drew T, Clinch P, et al. Psychomotor

RM. Challenges training left-handed surgeons. Am J Surg. 2016. http://dx.doi.org/10.1016/j.amjsurg.2016. 12.011. 18. Adusumilli PS, Kell C, Chang J-H, Tuorto S, Leitman

IM. Left-handed surgeons: are they left out. Curr Surg. 2004;61(6):587-591. 19. Lieske B. The left handed surgical trainee. Br Med J.

2008;337:a2883.

skills for endoscopic manipulations: differing abilities between right and left-handed individuals. Ann Surg. 1997;225(3):333-338.

20. Tchantchaleishvili V, Myers PO. Left-handedness—a

8. Grantcharov TP, Bardram L, Funch-Jensen P, Rosen-

21. Freeman MJ, Singh J, Chell P, Barber K. Modular

berg J. Impact of hand dominance, gender, and experience with computer games on performance in virtual reality laparoscopy. Surg Endosc. 2003;17(7): 1082-1085.

phakoemulsification training adapted for a left-handed trainee. Eye. 2004;18(1):35-37.

9. Canakci V, Ciçek Y, Canakci CF, et al. Effect of

handedness on learning subgingival scaling with curettes: a study on manikins. Int J Neurosci. 2004;114 (11):1463-1482. 10. Damore D, Rutledge J, Pan S, Knotek N, Ramundo

M. Handedness effects on procedural training in pediatrics. Clin Pediatr. 2009;48(2):156-160. 11. Middleton KK, Hamilton T, Tsai P-C, Middleton

DB, Falcone JL, Hamad G. Improved nondominant hand performance on a laparoscopic virtual reality simulator after playing the Nintendo Wii. Surg Endosc. 2013;27(11):4224-4231. 12. Sarker S-J, Telfah MM, Onuba L, Patel BP. Objective

assessment of skills acquisition during laparoscopic surgery courses. Surg Innov. 2013;20(5):530-538. 13. Kim JY, Ali R, Cremers SL, Yun S-C, Henderson BA.

Incidence of intraoperative complications in cataract surgery performed by left-handed residents. J Cataract Refract Surg. 2009;35(6):1019-1025. 14. Park J, Williams O, Waqar S, Modi N, Kersey T, Sleep

T. Safety of nondominant-hand ophthalmic surgery. J Cataract Refract Surg. 2012;38(12):2112-2116. 15. Gupta R, Guillonneau B, Cathelineau X, Baumert H,

Vallencien G. In vitro training program to improve ambidextrous skill and reduce physical fatigue during laparoscopic surgery: preliminary experience. J Endourol. 2003;17(5):323-325. 6

16. Haycock A, Cohen J, Saunders BP, Cotton PB,

handicap for training in surgery? J Surg Educ. 2010;67 (4):233-236.

22. Flatt AE. Is being left-handed a handicap? The short

and useless answer is yes and no. Proc (Bayl Univ Med Cent). 2008;21(3):304-307. 23. Moloney D, Bishay M, Ivory J, Pozo J. Failure of the

sliding hip screw in the treatment of femoral neck fractures: “left-handed surgeons for left-sided hips”. Injury. 1994;25:SB9-SB13. 24. Mehta S, Lotke PA. Impact of surgeon handedness and

laterality on outcomes of total knee arthroplasties: should right-handed surgeons do only right TKAs? Am J Orthop. 2007;36(10):530-533. 25. Pennington N, Redmond A, Stewart T, Stone M. The

impact of surgeon handedness in total hip replacement. Ann R Coll Surg Engl. 2014;96(6):437-441. 26. Burdett C, Theakston M, Dunning J, Goodwin A,

Kendall SWH. Left-handed surgical instruments—a guide for cardiac surgeons. J Cardiothorac Surg. 2016; 11(1):135. 27. Torgerson CS, Brydges R, Chen JM, Dubrowski A.

Drilling simulated temporal bones with left-handed tools: a left-hander’s right? Ann Otol Rhinol Laryngol. 2007;116(11):819-826. 28. Klukowski M, Wierzchowska A, Bielecki K. Left-

handed surgeons. Polish J Surg. 2007;79(6):461-463. http://dx.doi.org/10.2478/v10035-007-0071-1. 29. Kapoor S, Puranik MP, Uma SR. Practice perspectives

of left-handed clinical dental students in India. J Clin Diagn Res. 2016;10(10):ZC79-ZC83. Journal of Surgical Education  Volume ]/Number ]  ] 2017

30. Burdett C, Dunning J, Goodwin A, Theakston M,

34. Makay O, Icoz G, Ersin S. Surgeon’s view on the

Kendall S. Left-handed cardiac surgery: tips from set up to closure for trainees and their trainers. J Cardiothorac Surg. 2016;11(1):139.

limitations of left-handedness during endoscopic surgery. J Laparoendosc Adv Surg Tech A. 2008;18(2): 217-221.

31. Carrel T. Aortic root and proximal aortic arch replace-

35. Mbirimtengerenji N, Schaio J, Guo LY, Muula A.

ment (performed by a left-handed surgeon). Interact Cardiovasc Thorac Surg. 2017;24(1):158-160.

Association of the dominant hand and needle stick injuries for healthcare workers in Taiwan. Malawi Med J. 2012;24(3):56-60.

32. Pouw L, Tulloh B. Laparoscopic cholecystectomy for

the left-handed surgeon. Br J Surg. 1995;82(1):138.

36. Badalato GM, Shapiro E, Rothberg MB, et al. The da

Medina-Arana V. Technical modifications for laparoscopic cholecystectomy by the left-handed surgeon. J Laparoendosc Adv Surg Tech A. 2007;17(5):679-685.

vinci robot system eliminates multispecialty surgical trainees’ hand dominance in open and robotic surgical settings. JSLS. 2014;18(3), http://dx.doi.org/10.4293/ JSLS.2014.00399.

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33. Herrero-Segura A, López-Tomassetti Fernández EM,