Validation of a Porcine Knee Model for Training Arthroscopic Skills

Kyle Martin MD; Danny Gillis MD; Jesse Slade Shantz MD, MBA, FRCSC; Jeff Leiter MSc, PhD; Peter MacDonald MD, FRCSCDepartment of Surgery, University of Manitoba; Pan Am Clinic; Winnipeg, MB

Conclusion and Future Directions

Seven of the 15 most common orthopaedic procedures involve arthroscopy. Arthroscopic skills require that trainees deliberately practice technical skills in order to reach proficiency. Surgical simulation with cadaveric wet labratories and computer simulators is increasingly thought of as a solution to the eroding operative experience in the era of work-hour restrictions and patient safety concerns.

With regard to knee arthroscopy, previously validated evaluation tools have employed human cadaveric knees, which cost approximately $900 per specimen plus shipping, and require expensive infrastructure for storage and disposal. The high cost and relative scarcity of specimens makes this arthroscopic training and evaluation model unsustainable for many orthopaedic residency programs. It has resulted in most cadaveric arthroscopy training programs limiting skills training to diagnostic arthroscopy in order to maximize specimen use.

In contrast, the porcine knee is known to have similar anatomy to the human knee, and specimens are readily available and easily acquired in most communities. Porcine knees can be obtained for a cost of less than thirty dollars per specimen, and the associated costs of storage and disposal are also lower than those associated with human specimens.

Introduction

The goal of this study was to investigate the development of an inexpensive, reproducible model of arthroscopic surgery allowing training programs to teach residents complex arthroscopic skills in a safe environment. This goal was divided into the following two specific objectives:

1. Validate a porcine platform for the affordable training and objective skills evaluation of trainees for use in a core surgical skills curriculum.

2. Develop a model of meniscus tear in porcine knees allowing training and evaluation of partial meniscectomy in a residency program.

Purpose

Residents, orthopaedic sports medicine fellows, and orthopaedic sports medicine surgeons from the University of Manitoba were recruited to participate and consent was obtained. Participants completed pre-study surveys including level of training and arthroscopic surgical experience.

Participants were instructed to complete a diagnostic knee arthroscopy on a human cadaveric specimen and a porcine knee specimen in random order. Ten minutes were allotted for each arthroscopy. Participants were then given an unlimited amount of time to perform a partial meniscectomy on the porcine specimen. Hand movements were recorded in conjunction with each arthroscopic procedure.

The previously validated Objective Assessment of Arthroscopic Skills form (Figure 2) and a published checklist for diagnostic arthroscopy of the knee was used for un-blinded global skills assessment of each participant.

Methods Results (continued)

Discussion

ResultsA total of 15 people were recruited for participation in the study (Figure 4).

Cronbach’s α was calculated as a measure of internal consistency for each of the three procedure categories, as well as between the procedure categories (Figure 5).

Figure 1. The comparative anatomy of cadaveric porcine and human knees.

Figure 2. Objective Assessment of Arthroscopic Skills form utilized for unblinded global skills assessment.

Figure 3. Typical setup of the porcine arthroscopy station (A and B) and an example of the synchronized hand movement and arthroscopic view recordings (C and D).

Within the current medical era, maximizing patient safety by respecting the ethical principles of beneficence and nonmaleficence has increasingly become a topic of importance. Subsequently, society has assigned increased value to answering related questions pertaining to the optimization of resident work hours and education methods. As such, it is imperative that surgical training methods evolve to maximize patient safety while optimizing cost, resource availability and ease of implementation.

This study sought to address resident surgical skill education by investigating a novel approach to arthroscopic training with a porcine knee model. While the utilization of swine in other aspects of surgical training has developed, there is a paucity of literature regarding their use in arthroscopic education. The results of this study demonstrate a high degree of internal consistency in and between all three surgical simulation scenarios. In addition, years in practice had a strong correlation with skill level as measured by OAAS, and the strength of this correlation increased relative to surgical complexity.

These findings demonstrate that the porcine model is a reasonable surrogate for the human knee when performing arthroscopic educational exercises as it is able to differentiate variation in skill in a manner similar to the human cadaveric model. Furthermore, the porcine model continues to provide many benefits over a computer model such as fluid management, dynamic tissue resistance, and the ability to accommodate various surgical techniques and instruments. It is anticipated the future will demand an need for competency-based evaluations within orthopaedic training programs, and the porcine model will be easily adaptable to these scenarios while remaining cost effective.

Figure 7 : Total OAAS score relative to arthroscopic experience stratified according to each simulated procedure category.

References:. (1) Atesok et al., JAAOS, 2012, 410-22.; (2) Karam et al. JBJS (A), 2013, 95.; (3) Moorthy et al., BMJ, 2003, 1032-7.; (4) Voto et al. Arthroscopic Training, 1988, 134-7. (5) Barnes, Ann Surg, 1989, 118-21.; (6) Insel et al.,JBJS (A), 2009, 2287-95.; (7) Faulkner et al., Acad Med, 1996, 1363-5.; (8) Reznick et al., Am J Surg, 1997, 226-30.; (9) Garrett et al., JBJS (A), 2006, 660-7.; (10) Dath et al., Surg Endosc, 2004, 1800-4.; (11) Slade Shantz et al., Knee Surg Sports Traumatol Arthrosc, 2012, epub.; (12) Slade Shantz et al., Arthroscopy, 2013, 106-12; (13) Robert Poss, et al., JBJS, 2000, 1494-a-1494.

Acknowledgements: The authors would like to thank OMeGA Medical Grants Association, as this project was supported by a Core Competency Innovation Grant from OMeGA Medical Grants Association.

References/Acknowledgements

Level of TrainingLevel of TrainingLevel of TrainingNovice

Resident

Experienced Resident/

FellowFaculty

Number 5 7 3Years of Practice 2.0 4.0 27.0Blocks of Sports

Medicine Completed

0 5 N/A

Learning Course Participants 3 6 3

Comparison Cronbach's αHuman Diagnostic Arthroscopy 0.94Pig Diagnostic Arthroscopy 0.96Pig Partial Meniscectomy 0.96Between-simulation Comparison 0.90

Figure 5. The internal consistency of simulations.

A B C D

Figure 4. The characteristics of study participants.

0

0.25

0.50

0.75

1.00

0.840.800.78

Figure 6. The correlation of total OAAS score with years in practice.

Porcine Partial MeniscectomyPorcine Diagnostic ArthroscopyHuman Diagnostic Arthroscopy

Skill Examining / Manipulating Joint

Did not examine joint or position to give

improved visualization during

procedure.

Examined joint without diagnostic abilities and

lacked ability to facilitate view by

positioning.

Positioned knee appropriately after some difficulty with

visualization.

Used common positioning to

facilitate view during arthroscopy.

Used accepted and novel positioning to

perform the arthroscopy effortlessly.

TriangulatingInstruments

Could not insert instruments into

ports and maintain them in view. Unable locate instrument tips

without difficulty.

Unable to maintain instrument in field of

view consistently.

Found instruments with delay. Field of view wandered from

operative site but returned.

Found instruments quickly and began work. Occasionally delayed in orienting

camera to afford better visualization.

Immediately located instruments and

began work without delay. Kept

instrument in field of view at all times.

Controlling Fluid Flow and Joint Distension

Under/overdistended joint consistently due

to inappropriate matching of suction

and flow.

Achieved proper distension after delays. Some extravasation into

tissue due to overdistension.

Distended joint adequately after initial loss of pressure during

suction.

Joint distended appropriately

through control of flow and suction.

Minimal fluid extravasated with

constantly maintained field of view.

Maintaining Field of View

Often disoriented. Was unable to adjust

scope to improve visualization.

Maintained field of view part of the time.

Maintained and adjusted arthroscope to provide maximal

view with some difficulty.

Maintained field of view in same portal.

Changed portals quickly to improve

visualization.

Controlling Instruments

Was unable to perform tasks with

provided instruments. Caused cartilage

damage.

Repeatedly made tentative or awkward

moves with instruments.

Competently used instruments although occasionally appeared

stiff or awkward

Used instruments appropriately and

efficiently.

Made fluid moves with instruments and

used some instruments in novel

ways to increase efficiency.

Economizing Time and Planning Forward

Was unable to complete any portion

of the procedure.

Was able to complete components of the

procedure, but needed to discuss next move.

Completed all components of the

operation with some unnecessary moves

Was efficient, but continued

discovering new time saving

motions.

Showed economy of movement and

maximum efficiency.

Overall Possessed rudimentary

arthroscopic skills with only basic anatomical and

mechanical understanding.

Knew basic steps of procedure and

performed some independently.

Performed the procedure

independently.

Performed procedure with

changes to improve efficiency.

Performed the procedure with

minimal chance to improve efficiency.

Skill Level Novice Advanced Beginner Competent Proficient Expert

Monday, June 10, 2013