Determining the necessity for routine pathologic examinations in uncomplicated total hip and total knee arthroplasties

Non-neoplastic bone, joint, and soft tissue pathology: What every pathologist should know

The diagnosis of bone and soft tissue tumors is a skill which requires experience across multiple disciplines while their incidence is small. By contrast, the numbers of patients with non-tumorous diseases of bones, soft tissues, and joints dwarfs primary tumors by several orders of magnitude. The ability to successfully diagnose non-neoplastic diseases requires a knowledge of bone development, structure, remodeling, imaging, and tissue processing. This review summarizes the alterations of bones, joints, and to a lesser extent soft tissues that are encountered in the practice of everyday surgical pathology.

Routine Histopathologic Examination of Bone Obtained During Elective Primary Total Knee Arthroplasty May Not Be Necessary

Background

Many institutions require the routine collection of pathology samples from every primary total knee arthroplasty (TKA) performed. These policies are controversial, and their cost-effectiveness is difficult to define. We sought to judge the cost-effectiveness of one such policy according to World Health Organization recommendations.

Methods

We analyzed 3200 consecutive primary TKAs, comparing our presumed preoperative diagnoses against the diagnoses made by the pathologist. Diagnoses were categorized as concordant (matching), discrepant (not matching but without impact to patient management), or discordant (not matching and resulting in a direct change to patient management). An incremental cost-utility ratio analysis was performed to determine the cost-effectiveness of our institution's policy to routinely collect pathology samples from every primary TKA performed. Cost-effectiveness was defined by World Health Organization guidelines as a cost of less than $228,090 per quality-adjusted life year gained.

Results

Twelve pathology samples were lost before reaching a pathologist. From the remaining 3188 samples, we identified 3158 concordant cases, 29 discrepant diagnoses, and 1 discordant diagnosis. It cost an estimated $10,522.60 to identify each discrepant diagnosis and an estimated $305,155.36 to diagnose one discordant case in our cohort. Our incremental cost-utility ratio analysis revealed that we spent $305,155.36 to gain 0 quality-adjusted life years for our patients.

Conclusions

Routine histopathologic analysis of TKA samples was cost-ineffective in our patient cohort and may not be necessary during routine TKA.

Routine Pathologic Examination of the Femoral Head in Total Hip Arthroplasty: A Survey Study of the American Association of Hip and Knee Surgeons

Background

Current literature does not provide conclusive evidence on whether routine pathologic examination of femoral heads from total hip arthroplasty is indicated or cost-effective. As a result, there is substantial variation in opinion among surgeons related to this issue. Our study aim was to determine factors that impact surgeon propensity to order pathologic examination of femoral heads.

Methods

A 12-question survey was created to evaluate surgeon practices, indications, and patient care implications surrounding routine pathologic examination of femoral heads. The email survey was distributed to all members of the American Association of Hip and Knee Surgeons (n = 2598).

Results

There were 572 survey respondents. Out of all respondents, 28.4% always send femoral heads to pathology, and 27.6% reported an institutional requirement to do so. Of the 572 surgeons, 73.6% report femoral head pathology has never resulted in a change in patient disease course. Factors that increase the likelihood of surgeons ordering femoral head pathologic examination include institutional requirements, medicolegal concern, and prior experience with femoral head pathologic examination changing patients' disease course (P < .001). Cost concern decreases the likelihood of surgeons ordering femoral head pathologic examination (P = .0012).

Conclusions

A minority of surgeons routinely send femoral heads from total hip arthroplasty for pathologic examination, mostly because of institutional requirement. The majority of surgeons feel that femoral head pathologic examination never changes patient management, although others have infrequently detected malignancy and infection. Institutional policy, concern for litigation, and prior experience with discordant pathologic diagnoses increase femoral head pathologic examinations, while cost concern decreases them.

Routine Histopathologic Analysis of Hip and Knee Bone Specimens After Total Joint Arthroplasty

Total hip and total knee arthroplasties (THA/TKA) are some of the most common elective surgeries done in the United States. Routine histopathologic analysis of hip and knee bone specimens after total joint arthroplasty commonly occurs to identify unexpected pathologic findings and serves as a quality assurance measure. As the most common indication for THA and TKA is osteoarthritis, the practice of routine histopathologic analysis may not be routinely warranted. There is no clear consensus on the cost-effectiveness of this practice, and the literature has questioned both the clinical relevance of discrepancies between surgeon diagnosis and histopathological diagnosis and raised concerns about variance in the histological evaluation of resected specimens by pathologists. Femoral head analysis in the setting of femoral neck fractures has been previously reported, yet there is no clear overview for this topic in the setting of elective THA. The histopathologic features of bone specimens during routine total joint arthroplasty, the cost-effectiveness, and current recommendations will be reviewed.

Routine Pathologic Examination of Femoral Head Specimens from Total Hip Arthroplasty May Not Be Indicated or Cost-effective: A Systematic Review

Background

There is considerable disparity in institutional practices surrounding routine pathologic examination of femoral heads removed during total hip arthroplasty (THA). Multiple groups have studied the merits of routine femoral head pathology in THA, without clear consensus. We sought to further investigate the existing evidence on routine pathologic examination of femoral heads retrieved during THA to determine if this practice provides additional clinical value and is cost-effective.

Material and methods

To conduct a systematic review of the literature, a medical librarian was consulted to develop and perform comprehensive searches in PubMed (1809-present), Embase (embase.com 1974-present), CINAHL (EBSCO, 1937-present), and the Cochrane Central Register of Controlled Trials (Wiley). Final searches resulted in 727 references. Through multiple reviewer screenings and assessments of eligible full-text articles, we included 14 articles for review.

Results

Our systematic review yielded pathologic examination results from 17,388 femoral head specimens collected during THA. In 0.85% of cases, the pathologic diagnosis differed in a meaningful way from the preoperative clinical diagnosis. Routine pathology changed patient management in approximately 0.0058% of cases. The average cost for pathologic examination of each specimen was $126.38.

Conclusion

Routine pathologic examination of femoral heads retrieved during THA has limited impact on patient management. With an estimated 500,000 THAs performed in 2019, the economic feasibility of routine femoral head pathology is limited at an annual cost of up to $63,000,000 and cost per quality-adjusted life-year approaching infinity. However, surgeon discretion on a patient-specific or practice-specific basis should be used to make the final determination on the need for femoral head pathology.

Selective pathological examination following hip arthroplasty: A retrospective cohort study

BACKGROUND

Pathological examination of the femoral head after hip arthroplasty is often performed routinely. The cost-effectiveness of the examination with regard to identifying clinically relevant diagnoses has been a point of discussion. To date, recommendations on performing pathological examination based on patient characteristics, disease history or radiographic findings are scarce. The aim of this study was to gain insight in when to select a patient for pathological examination of the femoral head by means of the following research questions: "How many clinically relevant diagnoses does selective pathological examination identify?" "Which factors contribute to selection of the femoral head for conducting pathological examination?" "What are the costs of selective pathological examination for identifying clinically relevant diagnoses?"

HYPOTHESIS

Selective pathological examination of the femoral head results in higher ratios of identified clinically relevant diagnoses against substantially lower costs.

METHODS

A retrospective cohort study was performed over the period of 2010-2015. All pathological reports were collected from our hospital and screened for resected femoral heads after primary total hip arthroplasty (THA) or primary hemiarthroplasty (HA). The coherence between preoperative diagnosis and postoperative pathological diagnosis was defined as concordant, discrepant or discordant. The aim was to perform logistic regression analysis.

RESULTS

In total, 164 patients were included of 3998 hip arthroplasties performed during the study period with a mean age of 74±12.3 years including 54 (33%) male and 110 (67%) female of whom 112 (68%) underwent THA and 52 (32%) HA. A discrepancy in diagnosis was found in nine patients (6%) and discordance in three patients (2%). The most frequently reported reasons to perform pathological examination were malignancy in medical history n=86 (53%), avascular necrosis n=22 (13%), bone abnormality perioperatively n=19 (11%) and pathological fracture n=13 (8%). The factors that identified the unexpected clinically relevant diagnoses were pathological fracture (3 cases out of 13), bone abnormality perioperatively (2 out of 19), abnormalities on preoperative radiographs (1 out of 9) and to a lesser extent malignancy in history (2 out of 86). With costs of pathological examination of approximately €163 per femoral head, performed in 164 patients, the total costs of pathological examination resulted in €26,732. The cost per discrepant case (n=9) was €2970 and the cost per discordant case (n=3) was €8910.

CONCLUSION

Selective pathological examination of the femoral head following hip arthroplasty results in higher ratios of discrepant and discordant cases against substantially lower costs. Factors that identify clinically relevant diagnoses are pathological fracture, perioperative bone abnormality, abnormalities on preoperative radiographs and to a lesser extent malignancy in history.

LEVEL OF EVIDENCE

III; retrospective cohort study.

Evaluation of the Cost Effectiveness of Routine Histopathologic Femoral Head Analysis in Hip Arthroplasty

Purpose

Histopathologic analysis of femoral head specimens following total hip arthroplasty (THA) is a routine practice that represents a significant use of health care resources. However, it occasionally results in discovery of undiagnosed hematopoietic malignancy and other discrepant diagnoses such as avascular necrosis. The purpose of this study was to determine the rate of discordant and discrepant diagnoses discovered from routine histopathological evaluation of femoral heads following THA and perform a cost analysis of this practice.

Materials and Methods

A review of patients undergoing primary THA between 2004-2017 was conducted. A comparison of the surgeon’s preoperative and postoperative diagnosis, and the histopathologic diagnosis was performed. In cases where the clinical and histopathology differed, a review determined whether this resulted in a change in clinical management. Medicare reimbursement and previously published cost data corrected for inflation were utilized for cost calculations.

Results

A review of 2,134 procedures was performed. The pathologic diagnosis matched the postoperative diagnosis in 96.0% of cases. Eighty-three cases (4.0%) had a discrepant diagnosis where treatment was not substantially altered. There was one case of discordant diagnosis where lymphoma was diagnosed and subsequently treated. The cost per discrepant diagnosis was $141,880 and per discordant diagnosis was $1,669 when using 100% Medicare reimbursement and Current Procedural Terminology (CPT) code combination 88304+88311.

Conclusion

Histopathologic analysis of femoral head specimens in THAs showed an association with high costs given the rarity of discordant diagnoses. Routine use of the practice should be at the discretion of individual hospitals with consideration for cost and utility thresholds.

Unexpected Primary Extranodal Marginal Zone Lymphoma of Bone in Amputation and Arthroplasty Specimens

OBJECTIVES

Amputation due to gangrene and arthroplasty for degenerative joint disease are common orthopedic procedures and are expected to increase as populations age. Histopathologic examination of these specimens can identify unsuspected diseases.

METHODS

We reviewed gangrenous amputations and large joint arthroplasty specimens for diagnosis of unexpected lymphoma, January 2014 to January 2020. Pathology and medical records were reviewed to determine diagnosis, treatment, and outcome.

RESULTS

Five cases (0.08%) of unexpected primary extranodal marginal zone lymphoma (MZL) centered in bone were identified in 1,624 amputations for gangrene and 4,163 arthroplasty specimens. The female-to-male distribution was 3:2. Median age was 71 years (range, 62-87). The 3 cases arising in the setting of gangrene involved the first toe phalanges and metatarsals, and the femoral head was involved in all cases of joint disease (2 cases). The bone showed variable (10%-80%) infiltration by dense populations of small lymphoid cells with MZL immunophenotype. One patient died from sepsis 18.5 months after diagnosis; all others are alive with a median follow-up of 27.45 months.

CONCLUSIONS

Histopathologic examination of nonneoplastic orthopedic specimens identifies unexpected primary bone extranodal MZL in a small percentage of cases. This neoplasm may be the result of chronic antigenic stimulation in some circumstances.

Accurate and Reliable Diagnosis of Avascular Necrosis of the Femoral Head From Total Hip Arthroplasty Specimens Requires Pathologic Examination

OBJECTIVES

To evaluate the necessity of pathologic examination for confirming the diagnosis of avascular necrosis (AVN).

METHODS

We retrospectively reviewed consecutive nonfractured total hip arthroplasty cases (n = 1,722), comparing operative diagnoses and radiologic data with final histologic diagnoses, focusing specifically on AVN.

RESULTS

Among 199 histologically confirmed cases of AVN, 62 (31%) had a preoperative diagnosis of osteoarthritis/degenerative joint disease (OA/DJD); 58 of the latter patients had radiology reports, but only two (3%) documented AVN. Patients with AVN preoperatively diagnosed as OA/DJD were significantly older (mean, 65 years) than patients with AVN correctly diagnosed clinically (mean, 52 years; P < .00001). Among 163 cases with a preoperative diagnosis of AVN, 26 (16%) were confirmed as OA/DJD; the radiology report incorrectly diagnosed AVN in 17 (65%) patients. These latter patients also were significantly older (mean, 60 years) than patients with AVN correctly diagnosed clinically (P = .0008). Patients with a preoperative clinical and/or radiologic diagnosis of AVN were more likely to be younger and have known AVN risk factors.

CONCLUSIONS

Accurate and reliable diagnosis of AVN requires pathologic examination, especially among older patients without known risk factors. Prompt diagnosis may lead to behavioral changes in affected patients that reduce the risk of subsequent lesions.

The Incidence and Significance of Calcium Pyrophosphate Dihydrate Deposits in Histologic Examinations of Total Hip, Knee, and Shoulder Joint Arthroplasties

CONTEXT.—

The incidence, distribution, and significance of calcium pyrophosphate dihydrate deposition (CPPD) disease have not been extensively compared among various total joint resections.

OBJECTIVE.—

To investigate and define the clinical and pathologic features of CPPD in hip, shoulder, and knee arthroplasties.

DESIGN.—

We retrospectively reviewed consecutive total hip, knee, and shoulder arthroplasty cases (N = 3195) confirmed pathologically between January 1, 2017, and October 10, 2018, comparing clinical and pathologic data.

RESULTS.—

Among 2004 hip arthroplasties, 61 (3%) had CPPD on pathologic examination; the majority had a histologic diagnosis of osteoarthritis followed by fracture and avascular necrosis. Of 1113 knee arthroplasties, 98 (9%) had CPPD; all had a histologic diagnosis of osteoarthritis. Among 78 shoulder arthroplasties, 10 (13%) had CPPD; all but one had a histologic diagnosis of osteoarthritis. Patients with hip and knee CPPD were significantly older than those without CPPD. Of the 169 pathologically detected CPPD cases, only 35 (21%) were documented on preoperative radiologic images or by other clinical means; radiology reports were significantly more likely to document chondrocalcinosis in the knees than in the hips. Histologically, CPPD were noted almost exclusively in the separately submitted soft tissues/joint capsule, concomitantly involving the articular cartilage surface in only 3.0% (5 of 169) of cases.

CONCLUSIONS.—

Calcium pyrophosphate dihydrate deposition is more than twice as likely to occur in the knees and shoulders compared with the hips. Patients with CPPD in the knees or hips are usually not recognized preoperatively/radiologically and constitute a significantly older population. Reliably establishing the diagnosis of CPPD requires pathologic examination of the submitted soft tissue/joint capsule.

Discrepant histological diagnoses: A cause of early low FJS-12 score and if untreated, unhappy Total Knee Arthroplasty patient

PURPOSE

Total Knee Arthroplasty (TKA) is one of the most successful operations in orthopedics. Still, a sizable percentage of patients (20%) remain dissatisfied after a well-executed TKA. The study aims to examine the excised synovium from the suprapatellar region in osteoarthritic knees during TKA and evaluate the histopathology (HP) report to know whether discrepant diagnoses affect the Forgotten Joint Score-12 at various time intervals.

METHODS

This is a prospective cohort study. Two hundred (160 female; 40 male) end-stage osteoarthritis patients who underwent primary TKA were studied. An inclusion criterion was patient with end-stage osteoarthritis. Clinically and serologically proven rheumatoid arthritis patients were excluded from the study. The synovium excised during the TKA procedure was sent for the HP examination. The statistical significance was measured with the Chi-square test and two-sample t-test.

RESULTS

A total of 184 out of the 200 patients (92%) knee synovium showed HP features of osteoarthritis. The discordant diagnoses and discrepant diagnosis rate was 8% and 7%, respectively, which is statistically significant by Chi-square test (p value < 0.0001 and p value = 0.0001). 14 of the patients (12 F:2 M) showed histological features of inflammatory/rheumatoid arthritis who were treated, two patients (all female) showed HP features of villonodular synovitis. The mean (SD) improvement in FJS-12 at six weeks in the concordant group (25.3 [17.6]) is significantly more than the discrepant group (15.3 [12.5]), p-value 0.0385.

CONCLUSION

8% of our patients exhibited unexpected results. The study showed a 7% rate of discrepant diagnosis. This discrepant diagnosis if missed and untreated, would have affected the function and long-term survival of the implanted TKA.

Is There Value in Pathology Specimens in Routine Total Hip and Knee Arthroplasty?

Background Routine analysis of bone specimens in total joint arthroplasty (TJA) is mandatory at many institutions. The purpose of this study was to determine if mandatory routine TJA specimen analysis alters patient care or if they represent an unnecessary healthcare expenditure. Methods A retrospective review was performed of all primary TJA patients between October 2015 and December 2017 at our institution. Pathology results were reviewed to ascertain the number of concordant, discrepant, and discordant results. A diagnosis was considered concordant if the preoperative and pathologic diagnosis matched, discrepant if the preoperative and pathological diagnosis differed but no change in the patient's plan of care occurred, and discordant if the preoperative and pathologic diagnosis differed and resulted in a change in the patient's plan of care.  Results 3,670 total hip arthroplasty (THA) and total knee arthroplasty (TKA) procedures (3,613 patients) met the inclusion criteria and were included in this study. All 3,670 specimens had a concordant diagnosis; there were zero discrepant and zero discordant diagnoses. During the study period, our institution spent $67,246.88 in routine analysis of TJA specimens by a pathologist, with no change in any postoperative patient care plans. Conclusion With bundled payment reimbursement models and hospitals trying to decrease unnecessary expenditures, the present study helps further demonstrate that routine analysis has limited cost-effectiveness due to the low prevalence of alteration in the management of patient care. The decision for pathological analysis should be left at the discretion of the surgeon in order to maximize the cost-efficiency of TJA procedures.

Examination of total hip and knee arthroplasty tissues

BACKGROUND

Many practices require tissues from hip and knee arthroplasty procedures to be sent for pathologic examination. These examinations rarely provide information beyond the clinical or radiologic diagnosis and rarely alter clinical management. We aimed to determine the rate at which histologic diagnoses based on gross assessment alone or gross plus microscopic assessment correspond with reported clinical diagnoses in patients undergoing total joint arthroplasties and whether the histologic diagnoses alter patient management.

METHODS

We retrospectively reviewed arthroplasty cases performed at a high-volume teaching hospital in Manitoba, Canada. The clinical diagnosis was compared with the final pathology report based on gross examination, with or without histologic assessment. The results of the comparison were classified into 3 categories: concordant (same diagnosis), discrepant (different diagnoses without alterations in management) and discordant (different diagnoses resulting in management change). The overall provincial cost for pathologic examination was determined by multiplying the total examination cost by the estimated number of arthroplasty cases.

RESULTS

There were 773 patients in our study sample. The concordant rate was 98.3% (95% confidence interval [CI] 97.1%-99.1%), the discrepant rate was 1.7% (95% CI 0.9%-2.9%) and the discordant rate was 0.0% (95% CI 0%-0.5%) for 773 cases. The pathology diagnosis did not alter patient management in any case. A total of 91.5% of specimens did not require full histologic review and received gross descriptions only. The discrepancy rate was higher in cases that included microscopic examination than in those that received only gross descriptions (15.2% v. 0.4%, p < 0.001). The overall provincial cost for pathologic examination was estimated at Can$304 556.

CONCLUSION

Submitting routine tissue from arthroplasty procedures to pathology does not affect patient management and therefore provides no value for the health care resources expended in doing so.

Cost Analysis of Routine Examination of Pathology Specimens Following Ankle Arthroscopy

Background:

Routine submission of pathologic specimens for histologic analysis following orthopedic surgery is a common and often required practice in the United States. Prior orthopedic studies have determined that these histologic examinations are of limited cost effectiveness and low clinical value because rarely do the pathology findings alter patient management. The purpose of this study was to evaluate the cost effectiveness and clinical significance of routine histologic examination of tissue specimens removed during ankle arthroscopy.

Methods:

Between 2014 and 2018, 408 patients underwent ankle arthroscopy at a multi-center hospital system by 16 different orthopedic surgeons. The available pathology reports from these cases were retrospectively reviewed to determine if the routine histologic examination altered patient care. We compared the preoperative diagnosis to both the postoperative and histologic diagnoses. The total cost for these histologic examinations was estimated using 2017 Medicare physician fees released by the College of American Pathologists. Cost-effectiveness was estimated in 2017 US dollars by cost per discrepant and discordant diagnosis.

Results:

Of the 408 patients who underwent ankle arthroscopy, 361 pathology reports were available for review. The prevalence of concordant diagnosis was 98.9% (357/361); the prevalence of discrepant diagnoses was 1.0% (4/361). There were no cases identified with a discordant diagnosis. Total estimated cost for all pathology specimens was $46 381 in 2017 US dollars. Cost per discrepant diagnosis was $11 595.

Conclusion:

In our study, histologic examination of surgical specimens following ankle arthroscopy had no effect on patient management, yet it increased costs. Routine examination of these pathologic specimens had a low rate of discrepant and/or discordant diagnoses. Based on our results, routine pathologic examination of ankle arthroscopy tissue specimens should be sent solely at the discretion of the orthopedic surgeon as opposed to being a mandated policy.

Level of Evidence:

Level IV, case series.

Pathology Assessment of Femoral Head Resection Specimens: An Important Quality Assurance Procedure

CONTEXT.—

Decisions to perform hip arthroplasty rely on both radiographic and clinical findings. Radiologists estimate degree of osteoarthritis (OA) and document other findings. Arthroplasty specimens are sometimes evaluated by pathology.

OBJECTIVE.—

To determine the frequency of pathologic changes not recognized clinically.

DESIGN.—

Nine hundred fifty-three consecutive femoral head resections performed between January 2015 and June 2018, with recent radiologic and histologic study, were reviewed. We compared severity of OA reported by radiology and pathology. Findings unrecognized radiographically but recorded pathologically, and discrepancies between clinical diagnosis and pathology diagnosis, were tabulated.

RESULTS.—

Twenty-one cases of osteomyelitis were diagnosed radiographically or pathologically. Eight discrepancies were present. Fourteen osteomyelitis cases were recognized clinically. Pathology recognized 2 neoplasms missed radiographically. Avascular necrosis was diagnosed on pathology but not radiology in 25 cases, and 35 cases of avascular necrosis were seen radiographically but not pathologically. Osteoarthritis was graded both radiographically and pathologically from 0 to 3. Five hundred ninety-one of 953 cases (62%) were grade 3. Pathologists and radiologists had perfect agreement in 696 of 953 cases (73%). When grade of OA seen at pathology was correlated with surgeon, 2 groups of surgeons were detected: one with a low threshold for performance of hip arthroplasty (23%-28% low-severity OA) and the second with a high threshold (2%-5% low-severity OA).

CONCLUSIONS.—

Correlation between radiology and pathology diagnoses is high. Degree of OA present varies significantly between surgeons. Pathology discloses findings not recognized clinically.

Are Histological Examinations of Arthroplasty Specimens Performed Consistently Across the Country? A Large Database Study

BACKGROUND

It is currently unknown to what extent routine histological examination of joint arthroplasty specimens occurs across hospitals nationwide. Although this practice is neither supported nor refuted by the available evidence, given the increasing demand for joint arthroplasties, it is crucial to study overall utilization as well as its main drivers.

QUESTIONS/PURPOSES

Using national data on joint replacements, we aimed to evaluate: (1) What is the current use of routine histological examination of joint arthroplasty specimens? (2) Does the use vary by geographic location and hospital characteristics? (3) Has use changed over time?

METHODS

From the Premier Healthcare database (2006-2016) we included claims data from 87,667 shoulder (595 hospitals, median age 70 years, 16% nonwhite), 564,577 hip (629 hospitals, median age 65 years, 21% nonwhite), and 1,131,323 (630 hospitals, median age 66 years, 24% nonwhite) knee arthroplasties (all elective). Our study group has extensive experience with this data set, which contains information on 20% to 25% of all US hospitalizations. Included hospitals are mainly concentrated in the South (approximately 40%) with equal distributions among the Northeast, West, and Midwest (approximately 20% each). Moreover, the Premier data set has detailed billing information, which allows for evaluations of real-world clinical practice. There was no missing information on the main variables of interest for this specific study. We assessed frequency of histology examination (defined by Current Procedural Terminology codes) overall as well as by hospital characteristics (urban/rural, bed size, teaching status, arthroplasty volume), geographic region (Northeast, South, Midwest, West), and year. Given the large sample size, instead of p values, standardized differences were applied in assessing group differences where a standardized difference of > 0.1 (or 10%) was assumed to represent a meaningful difference between groups. For significance of trends, p values were applied. Percentages provided represent proportions of individual procedures.

RESULTS

In most hospitals, histology testing was either rare (1%-10%, used in 187 of 595, 189 of 629, and 254 of 630 hospitals) or ubiquitous (91%-100%, used in 121 of 595, 220 of 629, and 195 of 630 hospitals) for shoulder, hip, and knee arthroplasties, respectively. Overall, histology testing occurred more often in smaller hospitals (37%-53% compared with 26%-45% in larger hospitals) and those located in the Northeast (59%-68% compared with 22%-44% in other regions) and urban areas (32%-49% compared with 20%-31% in rural areas), all with standardized differences > 10%. Histologic examination is slowly decreasing over time: from 2006 to 2016, it decreased from 34% to 30% for shoulder arthroplasty, from 50% to 45% for THAs, and from 43% to 38% for TKAs (all p < 0.001).

CONCLUSIONS

Although overall use is decreasing, a substantial number of hospitals still routinely perform histology testing of arthroplasty specimens. Moreover, variation between regions and hospital types suggests that this practice is driven by a variety of factors. This is the first study addressing national utilization, which will be helpful for individual hospitals to assess how they compare with national utilization patterns. Moreover, the findings have clear implications for followup studies, which may be necessary given the exponentially growing demand for arthroplasties.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Assessing the Value of Routine Pathologic Examination of Resected Femoral Head Specimens After Femoral Neck Fracture

INTRODUCTION

The purpose of this study was to evaluate the efficacy of routine pathologic examination (PE) of femoral head (FH) specimens after arthroplasty for acute femoral neck fractures and to determine the cost.

METHODS

This was a retrospective chart review of 850 acute femoral neck fractures treated with hemiarthroplasty or total hip arthroplasty These were evaluated to determine whether the FH was sent for PE, the resultant findings, alterations in medical treatment, and cost.

RESULTS

A total of 466 FH specimens (54.8%) were sent to pathology. Four (0.9%) were positive for a neoplastic process. All four had a known history of cancer, antecedent hip pain, or an inappropriate injury mechanism. None of the findings resulted in an alteration in medical treatment. The average cost of PE was $195 USD.

DISCUSSION

The routine PE of FH specimens after arthroplasty for femoral neck fractures is not warranted and uneconomic. Sending the FH for PE, only when clinically indicated, rather than routine, will result in notable savings for the healthcare system.

LEVEL OF EVIDENCE

Level IV.

Cost-benefit analysis of routine pathology examination in primary shoulder arthroplasty

BACKGROUND

The annual number of shoulder arthroplasty procedures is continuing to increase. Specimens from shoulder arthroplasty cases are routinely sent for pathologic examination. This study sought to evaluate the clinical utility and associated costs of routine pathologic examination of tissue removed during primary shoulder arthroplasty cases and to determine cost-effectiveness of this practice.

METHODS

This is a retrospective review of primary shoulder arthroplasty cases. Patients whose humeral head was sent for routine pathologic examination were included. Cases were determined to have concordant, discrepant, or discordant diagnoses based on preoperative/postoperative diagnosis and pathology diagnosis. Costs were estimated in 2015 U.S. dollars, and cost-effectiveness was determined by the cost per discrepant diagnosis and cost per discordant diagnosis.

RESULTS

We identified 714 cases of primary shoulder arthroplasty in 646 patients who met inclusion criteria. The prevalence of concordant diagnoses was 94.1%, the prevalence of discrepant diagnoses was 5.9%, and no cases had discordant diagnoses. There were 172 cases that had biceps tendon specimens sent for pathology examination, and none led to a change in patient care. Total estimated costs were $77,309.34 in 2015 U.S. dollars. Cost per discrepant diagnosis for humeral head specimens was $1424.09, and cost per discordant diagnosis is at least $59,811.78.

DISCUSSION/CONCLUSION

Primary shoulder arthroplasty has a high rate of concordant diagnosis. Discrepant diagnoses were 5.9% in our study, and there were no discordant diagnoses. This study showed limited clinical utility in routinely sending specimens from primary shoulder arthroplasty cases for pathology examination, and calculation using a traditional life-year value of $50,000 showed that the standard for cost-effectiveness is not met.

Unsuspected Malignancies in Routine Femoral Head Histopathologic Examination During Primary Total Hip Arthroplasty: Cost-Effectiveness Analysis

BACKGROUND

Routine femoral head histopathology during primary total hip arthroplasty (THA) has been recently reported as a potentially useful screening tool for bone- and bone marrow-associated malignancies. However, cost-effectiveness of routine histopathology during THA remains unclear due to low prevalence of significant medical findings which alter patient management. The aim of this study was to evaluate the cost-effectiveness of routine histopathology in diagnosing unsuspected malignancy in patients undergoing primary THA.

METHODS

From 1993 to 2011, we retrospectively analyzed routine histopathologic findings of 3200 femoral head specimens from 2725 patients that underwent primary THA. Preoperative and postoperative diagnoses were classified into concordant (clinical diagnosis concurred with pathologic diagnosis), discrepant (differing diagnosis with no resultant impact on patient management), and discordant (differing diagnosis with subsequent change in patient management). Cost-effectiveness analysis was performed using the incremental cost-utility ratio.

RESULTS

A total of 3055 of 3200 pathologic samples were concordant with the preoperative diagnosis (95.4%), 140 of 3200 were discrepant (4.4%), and 5 of 3200 were discordant (0.2%). Routine histopathology revealed 1 unsuspected malignancy out of 640 (5 of 3200) femoral heads. The total cost of histopathologic screening was $614,664.80. The average cost to identify a discrepant case was $4390.46, and the cost to identify a discordant case was $122,932.96. The incremental cost-utility ratio was $49,569.74 per quality-adjusted life year (QALY) gained.

CONCLUSION

Our study indicates routine femoral head histopathology may be cost-effective in diagnosing unsuspected malignancy at $49,569.74/QALY gained (less than World Health Organization recommended threshold $159,000/QALY gained), providing useful clinical information for surgeons considering the value of routine femoral head histopathology in patients undergoing THA.

Correlation of Clinical, Operative, and Histopathologic Diagnosis of Interdigital Neuroma and the Cost of Routine Diagnosis

BACKGROUND

Diagnosis of an interdigital neuroma (IDN) is clinically based on patient symptoms. During operative excision, it is common to send the excised specimen for routine histopathologic examination. The purpose of this study was to evaluate the accuracy of the clinical and intraoperative diagnosis of IDN and correlate these with the histopathologic results of IDN.

METHODS

Case logs of 3 fellowship-trained foot and ankle surgeons were reviewed to identify all neuroma excisions completed between 1997 and 2014. Charts were reviewed to identify the preoperative clinical diagnosis and intraoperative diagnosis as well as concern for pathology besides a neuroma. All results were compared to final histopathology to identify instances of discordance between diagnoses. A total of 123 patients with 133 neuromas were identified.

RESULTS

Of the total 133 neuromas, 5 cases included a clinical or intraoperative concern for a diagnosis other than neuroma. In these 5 instances surgeons accurately identified cysts and rheumatoid nodules. 132 of 133 histopathology reports indicated the presence of nerve tissue in their report. There were no reports of malignancy or abnormal nerve tissue. There were no changes to the postoperative protocol based on histopathology.

CONCLUSION

The clinical, intraoperative, and histopathologic diagnosis of neuroma was in concordance 100% of the time. With a high level of clinical and intraoperative acumen in identifying a neuroma, we believe it is reasonable not to submit the specimen for histopathologic evaluation. In addition, limiting the amount of routine histopathologic evaluation could have saved approximately $480 per case.

LEVEL OF EVIDENCE

Level IV, case series.

Costs Versus Benefits of Routine Histopathological Examination in Total Ankle Replacement

BACKGROUND

Routine histopathological examination has previously been scrutinized as a source of extraneous cost in orthopedic foot and ankle care. As an increasingly prevalent joint replacement operation, total ankle replacement poses a notable cost to the health care market in an era of cost containment. The purpose of this study was to compare the costs and benefits of routine histopathological examination of specimens removed during total ankle replacement. We hypothesized that a new diagnosis would rarely be found and such examination would seldom alter patient care.

METHODS

A retrospective review was conducted of all total ankle replacement operations between 2006 and July 2014 at the investigators' institution. Medical records for 90 patients, undergoing a total of 95 total ankle replacement operations, were reviewed to determine the clinical and pathological diagnoses for each operation and, subsequently, the rates of discrepancy and discordance. Professional charges were determined using estimated reimbursement rates for the Current Procedural Terminology (CPT) codes billed: 88304 (level III microscopic examination), 88305 (level IV microscopic examination), and 88311 (decalcification).

RESULTS

Degenerative joint disease was diagnosed by the pathologist in 93.7% of cases (89/95), pseudogout in 4.2% (4/95), and rheumatoid arthritis in 2.1% (2/95). The 4 diagnoses of pseudogout were the only cases of new diagnoses based on pathological review. A total of $16,536.81 was spent for examination of all specimens, for an estimated $4,134.20 spent per discrepant diagnosis. Patient care was unaffected by pathological examination.

CONCLUSION

A new diagnosis was rarely found by histopathological examination, and patient care remained unaltered in all cases. The costs of routine histopathological examination of tissue specimens removed during total ankle replacement, therefore, outweigh clinical benefits, and such examination should be left to the discretion of the operating surgeon.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Routine Examination of Pathology Specimens Following Knee Arthroscopy: A Cost-Effectiveness Analysis

BACKGROUND

While the clinical value of routine pathologic examination of tissues removed during orthopaedic procedures has not been determined, limited cost-effectiveness and a low prevalence of findings that alter patient management have been previously demonstrated with arthroscopy. The purpose of this study was to examine the clinical value and cost-effectiveness of routine histological examination of knee arthroscopy specimens.

METHODS

Retrospective chart analysis of 3797 consecutive knee arthroscopies by two surgeons from 2004 to 2013 at three affiliated hospitals within one health-care system was undertaken. Pathology reports regarding tissue removed during partial meniscectomies and anterior cruciate ligament reconstructions were reviewed to determine if the results altered patient care. The total costs of histological examination were estimated in 2012-adjusted U.S. dollars. The cost per health effect was determined by calculating the cost per discrepant and discordant diagnosis.

RESULTS

The prevalence of concordant diagnoses was 99.3% (3769 of 3797), the prevalence of discrepant diagnoses was 0.7% (twenty-seven of 3797), and the prevalence of discordant diagnoses was 0.026% (one of 3797). The total cost of histological examinations was estimated to be $371,810. The total cost of the pathology cost per discrepant diagnosis was $13,771, and the cost per discordant diagnosis was $371,810.

CONCLUSIONS

Routine pathological examination of surgical specimens from patients undergoing knee arthroscopy had limited cost-effectiveness because of the low prevalence of findings that altered patient management. Histological examination of surgical specimens from arthroscopic knee surgery did not alter patient care and increased costs. We suggest that gross and histological examination of tissue removed during knee arthroscopy should be done at the discretion of the orthopaedic surgeon rather than being mandatory.

Comparison of clinical and histologic diagnoses in 16,587 total joint arthroplasties: implications for orthopedic and pathologic practices

OBJECTIVES

To confirm how often histologic diagnoses correspond to reported clinical diagnoses in patients undergoing total joint arthroplasties.

METHODS

We compared the submitting operative diagnosis with the pathologic diagnosis in 16,587 total joint arthroplasties for the seven most common diagnoses.

RESULTS

The discrepancy rates between the submitted operative and histologic diagnosis were 18.8% for 7,968 total hip replacements and 9.4% for 8,619 total knee replacements. In addition, 5.4% of hip joints and 1.4% of knee joints demonstrated discordant histologic findings that had not been suspected clinically and should have affected clinical management and patient outcomes.

CONCLUSIONS

Our findings demonstrated significantly more diagnostic discrepancies and discordance than has been suggested by the previously published literature. A large part of the difference may be due to more careful diagnostic analyses of orthopedic specimens than in other institutions. These analyses include some diagnoses that are not often made elsewhere but may have important future implications for patients.

Histologic examinations of arthroplasty specimens are not cost-effective: a retrospective cohort study

BACKGROUND

Many hospitals require all operative specimens be sent to pathologists for routine examination. Although previous studies indicate this practice increases medical cost, it remains unclear whether it alters patient management and whether it is cost-effective.

QUESTIONS/PURPOSES

We therefore (1) determined the rate of discordance between clinical and histologic examinations of routine operative specimens during elective primary arthroplasties, (2) determined the cost of routine histologic screening, and (3) estimated its cost-effectiveness in terms of cost per quality-adjusted life year gained, as compared with gross examination or no examination.

METHODS

We retrospectively reviewed medical records of 1247 patients who underwent 1363 routine elective primary total joint arthroplasties between January 18, 2006 and March 15, 2010. We compared preoperative, postoperative, and histologic diagnoses for each patient and categorized them into three classes: concordant (clinical and histologic diagnoses agreed), discrepant (diagnoses differed but with no resultant change in treatment), and discordant (diagnoses differed with resultant change in treatment). Medicare reimbursements were determined through the pathology department's administrative office.

RESULTS

In 1363 cases, 1335 (97.9%) clinical and histologic diagnoses were concordant, 28 (2.1%) were discrepant, and none were discordant. Total reimbursement for routine pathological examination was $139,532, or $102.37 per specimen. The average cost to identify each discrepant case was $4983.29. Routine histologic examination did not alter patient management, and there was no direct gain in quality-adjusted life years.

CONCLUSIONS

Our observations show routine histologic examinations of routine operative specimens during elective primary arthroplasties increase medical cost but rarely alter patient management and are not cost-effective.

LEVEL OF EVIDENCE

Level I, economic and decision analyses. See Guidelines for Authors for a complete description of levels of evidence.

Histopathology of femoral head donations: a retrospective review of 6161 cases

BACKGROUND

Although total hip arthroplasty is one of the most common orthopaedic surgical procedures, it remains unclear whether histopathological examination of the excised femoral head adds to the quality of patient care. We propose that assessment of femoral heads resected during total hip arthroplasty and donated for allograft use may provide a profile of femoral head pathology that benefits total hip arthroplasty patients and bone donors.

METHODS

We retrospectively analyzed the histological findings reported for 6161 femoral heads donated for allograft use between 1993 and 2006. Specimens obtained during total hip arthroplasty and specimens donated at death were reviewed. Follow-up investigations that resulted from abnormal histopathological findings were also reviewed. The Western Australian Cancer Registry was used to determine whether patients with a suspected neoplasm were subsequently diagnosed with such a disease. A retrospective review of the histopathological findings was conducted to evaluate and reclassify all previous observations of abnormalities.

RESULTS

One hundred and five femoral heads demonstrated abnormal or reactive histopathological features not reported prior to surgery and were rejected for allograft use. A reactive lymphocytic infiltrate, most likely due to osteoarthritis, was the most commonly identified feature (forty-five cases). Other features observed in twenty-seven cases were also most likely due to the presence of severe osteoarthritis. Ten femoral heads demonstrated plasmacytosis, which may have been related to osteoarthritis. Two patients were diagnosed with Paget's disease, and two, with rheumatoid arthritis. Nineteen patients had a suspected neoplasm. Of these nineteen, eight cases of non-Hodgkin's lymphoma or chronic lymphocytic leukemia and one case of myelodysplastic syndrome were confirmed on further investigation. One subsequently confirmed malignancy was detected per 770 femoral heads examined.

CONCLUSIONS

Our findings indicate that, even with a detailed medical history and careful physical examination, clinically important diseases including neoplasms and Paget's disease are observed in patients diagnosed with osteoarthritis prior to total hip arthroplasty. Histological examination plays an integral role in quality assurance in femoral head banking, and it also represents a possible early diagnostic test for bone and bone-marrow-related diseases in patients undergoing total hip arthroplasty.

The value of routine histopathology during hip arthroplasty in patients with degenerative and inflammatory arthritis

The purpose of this study was to evaluate the effectiveness of routine pathological examination of operative specimens obtained during primary total hip arthroplasty (THA) performed for osteoarthritis (OA) and rheumatoid arthritis (RA). 100 consecutive patients (50 OA, 50 RA) were prospectively evaluated. A radiological score (Kellgren-Lawrence/Larsen) and a clinical score (Harris Hip Score) were calculated in each case. Specimens of bone and cartilage from the femoral head as well as capsule were obtained intraoperatively. A histological grading (Mankin score) was obtained, and additional histological findings were also reported. In patients with RA the clinical and pathological diagnoses were concordant in 37 (74%) and discrepant in 13 patients (26%). In patients with OA there was concordance in 30 (60%) and discrepancy in 20 patients (40%). Discrepancies were additional findings such as focal osteonecrosis amyloidosis or crystal deposits. Discordance (management alteration) did not occur in any case. Histological evaluation of the capsule and the synovium was more informative than evaluation of bone. Calcium pyrophosphate (CPPD) and amyloid was frequently found in OA suggesting that these substances may contribute to joint damage, and control of their production by therapeutic means may prevent degeneration.

Routine histopathologic evaluation in hallux valgus surgery

BACKGROUND

Anecdotal evidence suggests that specimens submitted for histopathologic assessment during hallux valgus surgery most commonly reveal degenerative changes. The purpose of this study was to evaluate the cost effectiveness of routine examination of tissue from hallux valgus procedures. We hypothesized that such examination rarely diagnoses a new condition and does not alter postoperative management.

MATERIALS AND METHODS

Specimens from 315 consecutive primary hallux valgus reconstructions performed between November 1995 and August 2002 were retrospectively analyzed. Patient charts were reviewed to determine the number of cases in which new diagnoses were made or treatment altered based upon histopathologic examination. Cost effectiveness was assessed by identifying the reimbursement for professional fees charged for these analyses. The total reimbursement per new diagnosis made and per alteration of treatment were calculated.

RESULTS

Degenerative changes were diagnosed in the majority of speciments (97.5%, 307 of 315). Other diagnoses included rheumatoid arthritis (1.3%, four of 315), gouty arthritis (1.0%, three of 315), and pseudogout (0.3%, one of 315). A new diagnosis was made only in the one patient (0.3%, one of 315) with pseudogout. Postoperative management was unchanged in every case.

CONCLUSION

Routine submission of specimens obtained during hallux valgus surgery is not cost effective. New diagnoses are very rare and postoperative management did not change.

B-cell lymphoma in retrieved femoral heads: a long term follow up

Background

A relatively high incidence of pathological conditions in retrieved femoral heads, including a group of patients having low grade B-cell lymphoma, has been described before. At short term follow up none of these patients with low-grade B-cell lymphoma showed evidence of systemic disease. However, the long term follow up of these patients is not known.

Methods

From November 1994 up to and including December 2005 we screened all femoral heads removed at the time of primary total hip replacement histopathologically and included them in the bone banking protocol according to the guidelines of the American Associations of Tissue Banks (AATB) and the European Association of Musculo-Skeletal Transplantation (EAMST). We determined the percentage of B-cell lymphoma in all femoral heads and in the group that fulfilled all criteria of the bone banking protocol and report on the long-term follow-up.

Results

Of 852 femoral heads fourteen (1.6%) were highly suspicious for low-grade B-cell lymphoma. Of these 852 femoral heads, 504 were eligible for bone transplantation according to the guidelines of the AATB and the EAMST. Six femoral heads of this group of 504 were highly suspicious for low-grade B-cell lymphoma (1.2%). At long term follow up two (0.2%) of all patients developed systemic malignant disease and one of them needed medical treatment for her condition.

Conclusion

In routine histopathological screening we found variable numbers of low-grade B-cell lymphoma throughout the years, even in a group of femoral heads that were eligible for bone transplantation. Allogenic transmission of malignancy has not yet been reported on, but surviving viruses are proven to be transmissible. Therefore, we recommend the routine histopathological evaluation of all femoral heads removed at primary total hip arthroplasty as a tool for quality control, whether the femoral head is used for bone banking or not.

The clinical value of histologic examination in shoulder arthroscopy

BACKGROUND

The clinical value of histologic examination of tissues removed during shoulder arthroscopy has not been determined. The guidelines of the College of American Pathologists require routine histologic examination of all surgical specimens not specifically exempted by individual hospitals. Previous orthopaedic studies have examined the clinical value of these examinations in total hip and knee arthroplasty, lumbar discectomy, knee arthroscopy, and thumb arthroplasty. Those studies demonstrated that routine histologic examination rarely altered the diagnosis and increased the costs. This study examines the clinical value of histologic examination of shoulder arthroscopic specimens. We regard clinical value to include both diagnostic value and cost of the procedure.

METHODS

Between 1989 and 2005, 2144 consecutive shoulder arthroscopies were performed by one surgeon. We retrospectively reviewed the pathology report from every procedure to determine whether the histologic diagnosis affected patient care. We then estimated the total cost of histologic examination in 2005 dollars.

RESULTS

In all cases, the histologic examination confirmed the findings at arthroscopic surgery. In no case did the histologic findings alter patient care. In 2005 dollars, the total cost of reviewed histologic examinations is estimated to be $160,543.

CONCLUSIONS

Histologic examination of surgical specimens from arthroscopic shoulder surgery does not alter patient care, and it increases costs. On the basis of this study, histologic examination in shoulder arthroscopy should be done at the discretion of the orthopaedic surgeon rather than being mandatory.

Unsuspected non-Hodgkin's lymphoma discovered with routine histopathology after elective total hip arthroplasty

The utility and cost-effectiveness of routine histologic examination of specimens from elective total joint procedures continues to be a source of debate. We describe a case of unsuspected non-Hodgkin's lymphoma discovered after routine histopathologic examination of a femoral head with osteoarthritis. The evidence both for and against routine tissue submission after elective arthroplasty cases is outlined in a review of the literature. By illustrating a neoplasm that would have been missed without routine pathologic examination, this case underscores a need for continued scrutiny of methods to effectively reduce medical costs while maintaining quality of care.

Cost and effectiveness of routine pathological examination of operative specimens obtained during primary total hip and knee replacement in patients with osteoarthritis

BACKGROUND

The challenge of cost-efficiency is maintaining the quality of medical care while reducing costs and eliminating unnecessary practices. The purpose of this investigation was to evaluate the cost and effectiveness of routine pathological examination of surgical specimens from patients undergoing primary total hip or knee replacement for the treatment of osteoarthritis.

METHODS

Effectiveness was assessed by comparing clinical and pathological diagnoses associated with 1,234 consecutive primary total joint replacements (471 hip and 763 knee replacements) performed between 1992 and 1995 in one hospital in patients with the clinical diagnosis of osteoarthritis. Clinical and pathological diagnoses were considered concordant if they agreed, discrepant if they differed without a resultant change in patient management, and discordant if they differed with a resultant change in patient management. Cost identification was performed by determining charges, reimbursement, and costs in 1998-adjusted American dollars for both total hip and total knee replacement. The cost per health-effect was determined by calculating the cost per discrepant and discordant diagnosis.

RESULTS

The prevalence of concordant diagnoses was 97.6 percent (1,205 of 1,234) (95 percent confidence interval, 96.6 to 98.4 percent), the prevalence of discrepant diagnoses was 2.3 percent (twenty-eight of 1,234) (95 percent confidence interval, 1.4 to 3.1 percent), and the prevalence of discordant diagnoses was 0.1 percent (one of 1,234) (95 percent confidence interval, 0.1 to 0.3 percent). The cost per discrepant diagnosis was $4,383, and the cost per discordant diagnosis was $122,728.

CONCLUSIONS

Routine pathological examination of surgical specimens from patients undergoing primary total hip or knee replacement because of the clinical diagnosis of osteoarthritis had limited cost-effectiveness at our hospital due to the low prevalence of findings that altered patient management.