Does Pathologic Evaluation of Tissue after Knee Arthroscopy Have Clinical Value?
With more than 1 million procedures annually, knee arthroscopy is one of the most commonly performed orthopaedic surgeries in the United States. 
Tissues removed during arthroscopic knee procedure are routinely sent to the pathology lab for histologic examination, in accordance with requirements from the College of American Pathologists  and The Joint Commission.  Both groups allow for exceptions – for example, the clinical staff and pathologists might determine that tissue from certain procedures, such as knee arthroscopy, could be exempt from routine evaluation if doing so would not compromise patient care. [3,4]
Should tissues removed during knee arthroscopy be one of the exemptions? Is there clinical value in the routine pathologic evaluation of the tissues? Does it really change how surgeons manage these patients?
And, just as important, are the costs of the evaluation justified?
Giles R. Scuderi, MD, and colleagues from the Insall Scott Kelly Institute for Orthopaedics and Sports Medicine in New York sought to answer those questions in a study recently published in the Journal of Bone & Joint Surgery. 
“With the introduction of the Affordable Care Act, bundled payments, and the cost of the episode of care,” Dr. Scuderi said, “we wanted to look at potential cost savings that would not impact patient care.”
To accomplish this, he and his colleagues conducted a retrospective chart analysis of 3,797 consecutive knee arthroscopies performed by two surgeons from 2004 to 2013 at three hospitals in a single healthcare system.  The procedure was done to repair a torn meniscus or to reconstruct an anterior cruciate ligament.
The histologic diagnosis concurred with the preoperative diagnosis in 3,769 of 3,797 cases (99.3%). The prevalence of concordant diagnoses was 99.3% (3,769 of 3,797), the prevalence of discrepant diagnoses was 0.7% (27 of 3,797), and the prevalence of discordant diagnoses was 0.026% (1 of 3,797). 
Although the percentage of discrepant diagnoses was low, Dr. Scuderi pointed out that “patient care is paramount, and it should be up to the surgeon, who may have a high index of suspicion for a discordant result, to request pathologic evaluation.”
“In our study,” he continued, “routine examination of arthroscopic tissue is consistent with the preop diagnosis. If the surgeon has any concerns based on physical examination, additional tests, such as radiographs, magnetic resonance imaging (MRI), or other advanced imagining studies, could be performed before requesting histologic evaluation of the specimen.”
The total cost of histologic examinations was estimated at $37,810. The total cost of the pathology cost per discrepant diagnosis was $13,771, and the cost per discordant diagnosis was $371,810. 
Although this study lacked a control group and blinded independent investigator, Dr. Scuderi pointed out that “this was a consecutive series. The pathologist reports the histologic diagnosis and is not involved in the decision-making process regarding indications for surgery.”
The results of this study demonstrated that routine pathologic examination of surgical specimens from patients undergoing knee arthroscopy had limited cost effectiveness because of the low prevalence of findings that altered patient management. Dr. Scuderi is hopeful that “the results of this study may have an impact as hospitals look at the cost of healthcare delivery, especially with respect to the ACA.”
Might there be legal implications in permitting surgeons to decide whether to send tissue for gross and histologic examination? “There are always implications,” Dr. Scuderi said, “but the decision should be made on the scientific evidence.”
“The patient is central to all decision making, and while we cannot compromise their care or outcome, we can endeavor to establish guidelines within our institutions.”
1. National Center for Health Statistics. National Health Statistics Reports. AmbulatorySurgery in the United States, 2006. http://www.cdc.gov/nchs/data/nhsr/nhsr011.pdf
2. Nakhleh RE, Fitzgibbons PL, editors. Quality improvement manual in anatomic pathology, 2nd ed. Northfield, IL: College of American Pathologists; 2002. Appendix.
3. The Joint Commission. Laboratory services. Quality system assessment for nonwaived testing. Submission of tissue to pathology. 2008 Nov 24. http://www.jointcommission.org/standards_information/jcfaqdetails.aspx?StandardsFaqId=295&ProgramId=47
4. Anatomic pathology checklist. Laboratory Accreditation Program. College of American Pathologists. 2007 Sep 27; p 14. http://www.cap.org/apps/docs/laboratory_accreditation/checklists/anatomic_pathology_Sep07.pdf
5. Greene JW, Zois T, Deshmukh A, Cushner FD, Scuderi GR. Routine examination of pathology specimens following knee arthroscopy: a cost-effectiveness analysis. J Bone Joint Surg Am. 2014;96:917-21.