Lower Perioperative Complication Rates and Shorter Lengths of Hospital Stay Associated With Technology-Assisted Total Knee Arthroplasty Versus Conventional Instrumentation in Primary Total Knee Arthroplasty

BACKGROUND

The use of technology allows increased precision in component positioning in total knee arthroplasty (TKA). The objectives of this study were to compare (1) perioperative complications and (2) resource utilization between robotic-assisted (RA) and computer-navigated (CN) versus conventional (CI) TKA.

METHODS

A retrospective cohort study was performed using a national database to identify patients undergoing unilateral, primary elective TKA from January 2016 to December 2019. A total of 2,174,685 patients were identified and included RA (69,445), CN (112,225), or CI (1,993,015) TKA. Demographics, complications, lengths of stay, dispositions, and costs were compared between the cohorts. Binary logistic regression analysis was performed.

RESULTS

The RA TKA cohort had lower rates of intraoperative fracture (0.05 versus 0.08%, P < .05), respiratory complications (0.6 versus 1.1%, P < .05), renal failure (1.3 versus 1.7%, P < .05), delirium (0.1 versus 0.2%, P < .05), gastrointestinal complications (0.04 versus 0.09%, P < .05), postoperative anemia (8.9 versus 13.9%, P < .05), blood transfusion (0.4 versus 0.9%, P < .05), pulmonary embolism, and deep vein thrombosis (0.1 versus 0.2%, P < .05), and mortality (0.01 versus 0.02%, P < .05) compared to conventional TKA, though the cohort did have higher rates of myocardial infarction (0.09 versus 0.07%, P < .05). The CN cohort had lower rates of myocardial infarction (0.02 versus 0.07%, P < .05), respiratory complications (0.8 versus 1.1%, P < .05), renal failure (1.5 versus 1.7%, P < .05), blood transfusion (0.8 versus 0.9%, P < .05), pulmonary embolism (0.08 versus 0.2%, P < .05), and deep vein thrombosis (0.2 versus 0.2%, P < .05) over CI TKA. Total cost was increased in RA (16,190 versus $15,133, P < .05) and CN (17,448 versus $15,133, P < .05). However, the length of hospital stay was decreased in both RA (1.8 versus 2.2 days, P < .05) and CN (2.1 versus 2.2 days, P < .05).

CONCLUSIONS

Technology-assisted TKA was associated with lower perioperative complication rates and faster recovery.

Miscoding in the Nationwide Inpatient Sample Database Raises Questions About Validity for Arthroplasty Research

BACKGROUND

The use of administrative databases in arthroplasty research has increased over the past decade. The Nationwide Inpatient Sample (NIS) is one of the first and most frequently used. Despite many published articles using this dataset, there exists no standardization resource accounting for the potential of biased results. The purpose of our study was to assess the amount of discordant data between clinically relevant variables and propose a standard for using this database in primary total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

An initial set of patients undergoing total joint arthroplasty were identified from the NIS between 2016 and 2019 using the International Classification of Diseases, 10th Revision, Procedure Coding System. All records with THA and TKA in any of the procedure variables (PR1-PR20) were included. A total of 63 relevant and consistent variables were selected for individual comparison including diagnosis-related group (1), elective (1), procedure codes (20), day of main procedure (1), and diagnosis codes (40). Descriptive statistics were used. A total of 3,562,819 patients were included in the initial set.

RESULTS

Using diagnosis-related groups, 5.3% were revision surgeries, 4.7% were not elective, 2.3% did not have THA or TKA as their primary procedure for hospitalization, and 2.9% of THA and 9.7% of TKA were bilateral. A total of 6.2% of the surgeries were done day(s) before or after admission, and 10.8% of THA and 6.3% of TKA were missing an orthopedic diagnosis for admission. Many had multiple orthopedic diagnoses for admission, 3.2% of THA and 0.7% of TKA. Overall miscoding was 23.3%.

CONCLUSIONS

Using the NIS without standardized data processing to study elective, unilateral, primary THA and TKA introduces major bias. A logical and stepwise approach to curate the data before analysis is proposed to improve research quality when using this database in hip and knee arthroplasty studies.

An overview of occupational injuries among female orthopaedic surgeons

Introduction

The aim of this study was to assess occupational injuries among female orthopaedic surgeons and compare these rates to their male counterparts.

Methods

An electronic survey was developed to assess occupational injuries among female orthopaedic surgeons. Descriptive statistics were analyzed for all survey items, and chi-squared tests and paired t-tests were used when appropriate.

Results

169 female orthopaedic surgeons completed this survey, the average age was 50 years old. MSK Injuries: Among the 169 responding surgeons, there were a total of 320 work-related musculoskeletal injuries. Non-MSK Occupational Injuries: Female orthopaedic surgeons experience social isolation at much higher rates than their male counterparts (53.8 % and 32.9 % respectively, p < 0.0001) as well as psychological distress since beginning practice (61.5 % and 55.3 % respectively). Additionally, female orthopaedic surgeons report higher rates of burnout (72.2 %, p = 0.01) compared to male orthopaedic surgeons (63.4 %). Female orthopaedic surgeons also sought out counseling from mental health professionals at higher rates than their male counterparts since beginning training (37.3 % and 28.6 % respectively, p = 0.02). 13.1 % of female respondents reported having been diagnosed with cancer since starting practice. Additionally, 94.6 % of female orthopaedic surgeons have experienced a finger stick and 16.1 % of female orthopaedic surgeons have experienced hearing loss since beginning practice.

Discussion

This study assesses the occupational injuries that affect female orthopaedic surgeons' physical and mental well-being. We found that in comparison to male orthopaedic surgeons, the major differences were found in the psychological and emotional domains. Women reported experiencing burnout and social isolation as well as seeking professional counseling at significantly higher rates than males; however, both genders reported concerningly high numbers. This could suggest that more resources need to be made available to help orthopaedic surgeons cope with the stresses of their demanding profession, with a specific emphasis on reducing work-related stress among female orthopaedic surgeons.

Varying Complication Rates and Increased Costs in Technology-Assisted Total Hip Arthroplasty Versus Conventional Instrumentation in 1,372,300 Primary Total Hips

BACKGROUND

The use of technology allows surgeons increased precision in component positioning in total hip arthroplasty (THA). The objective of this study was to compare (1) perioperative complications and (2) resource utilizations between robotic-assisted (RA) and computer-navigated (CN) versus conventional instrumenttaion (CI) THA.

METHODS

A retrospective cohort study was performed using a large national database to identify patients undergoing unilateral, primary elective THA from January 1, 2016 to December 31, 2019 using RA, CN, or CI. There were 1,372,300 total patients identified and included RA (29,735), CN (28,480), and CI (1,314,085) THA. Demographics, complications, lengths of stay, dispositions, and costs were compared between the cohorts. Binary logistic regression analyses were performed.

RESULTS

The use of RA THA led to lower rates of intraoperative fracture (0.22% versus 0.39%), delirium (0.1% versus 0.2%), postoperative anemia (14.4% versus 16.7%), higher myocardial infarction (0.13% versus 0.08%), renal failure (1.7% versus 1.6%), blood transfusion (2.0% versus 1.9%), and wound dehiscence (0.02% versus 0.01%) compared to CI THA. The use of CN led to lower rates of respiratory complication (0.5% versus 0.8%), renal failure (1.1% versus 1.6%), blood transfusion (1.3% versus 1.9%), and pulmonary embolism (0.02% versus 0.1%) compared to CI THA. Total costs were increased in RA ($17,729 versus $15,977) and CN ($22,529 versus $15,977). Lengths of hospital stay were decreased in RA (1.8 versus 1.9 days) and CN (1.7 versus 1.9 days).

CONCLUSIONS

Perioperative complication rates vary in technology-assisted THA, with higher rates in RA THA and lower rates in CN THA, relative to CI THA. Both RA THA and CN THA were associated with more costs, shorter postoperative hospital stays, and higher rates of discharge home compared to CI THA.

Increased Risk of In-Hospital Complications and Costs After Total Hip Arthroplasty for Primary and Secondary Osteonecrosis

BACKGROUND

An increasing proportion of patients are undergoing total hip arthroplasty (THA) for osteonecrosis (ON). Comorbid conditions and surgical risk factors are known to be greater in ON patients compared with patients who have osteoarthritis (OA) alone. The purpose of our study was to quantify the specific in-hospital complications and resource utilization associated with patients undergoing THA for ON versus OA.

METHODS

A large national database was queried to identify patients undergoing primary THA from January 1, 2016 to December 31, 2019. A total of 1,383,880 OA, 21,080 primary ON, and 54,335 secondary ON patients were identified. Demographics, in-hospital complications, costs, lengths of stay, and discharge dispositions for primary and secondary ON cohorts were compared to OA only. Age, race, ethnicity, comorbidities, Medicaid, and income status were controlled with binary logistic regression analyses.

RESULTS

The ON patients were often younger, African American or Hispanic, and had more comorbidities. Those undergoing THA for primary and secondary ON had a significantly higher risk of perioperative complications, including myocardial infarction, postoperative blood transfusion, and intraoperative bleeding. Total hospital costs and lengths of stay were significantly higher for both primary ON and secondary ON and both cohorts were less likely to be discharged home.

CONCLUSION

While rates of most complications have decreased over recent decades in ON patients undergoing THA, the ON patients still have worse outcomes even when controlling for comorbidity differences. Bundled payment systems and perioperative management strategies for these different patient cohorts should be considered separately.

Chronic Opioid Use Independently Increases Complications and Resource Utilization After Primary Total Joint Arthroplasty

BACKGROUND

Current literature suggests a link between the chronic use of opioids and musculoskeletal surgical complications. Given the current opioid epidemic, the need to elucidate the effects of chronic opioid use (OD) on patient outcomes and cost has become important. The purpose of this study was to determine if OD is an independent risk factor for inpatient postoperative complications and resource utilization after primary total joint arthroplasty.

METHODS

A total of 3,545,565 patients undergoing elective, unilateral, primary total hip (THA) and knee (TKA) arthroplasty for osteoarthritis from January 2016 to December 2019 were identified using a large national database. In-hospital postoperative complications, length of stay, and total costs adjusted for inflation in opioid + patients were compared with patients without chronic opioid use (OD). Logistic regression analyses were used to control for cofounding factors.

RESULTS

OD patients undergoing either THA or TKA had a higher risk of postoperative complications including respiratory (odds ratio (OR): 1.4 and OR: 1.3), gastrointestinal (OR: 1.8 and OR: 1.8), urinary tract infection (OR: 1.1 and OR: 1.2), blood transfusion (OR: 1.5 and OR: 1.4), and deep vein thrombosis (OR: 1.7 and OR: 1.6), respectively. Total cost ($16,619 ± $9,251 versus $15,603 ± $9,181, P < .001), lengths of stay (2.15 ± 1.37 versus 2.03 ± 1.23, P < .001), and the likelihood for discharge to a rehabilitation facility (17.8 versus 15.7%, P < .001) were higher in patients with OD.

CONCLUSION

OD was associated with higher risk for in-hospital postoperative complications and cost after primary THA and TKA. Further studies to find strategies to mitigate the impact of opioid use on complications are required.

Relative frequency of primary total hip arthroplasty for avascular necrosis in the United States as compared to a regional center: A data review

Background

The relative frequencies of indications for primary total hip arthroplasty (THA) are not well-established. This study aims to establish the incidence of THA performed for Avascular Necrosis of the hip (AVN), as well as the other most common indications for THA in the United States, as compared to the incidences at a high-volume tertiary referral center in Miami, Florida. We hypothesize that the relative incidence of AVN and each other indication for THA will vary significantly between the United States as a whole and the tertiary referral center.

Methods

A query of the 2016-2017 National Inpatient Sample (NIS) and a tertiary referral center adult reconstruction registry was completed. The relative frequencies of each indication for THA, demographics, and behavioral risk factors were analyzed.

Results

225,061 primary THA patients in the National Inpatient Sample database and 447 in the Miami tertiary referral center database were included in the final analysis. The proportion of primary THA for AVN in the NIS database (5.97%) was significantly lower than the same proportion in the tertiary referral center database (22.2%), p < .001. There was no significant difference in the incidence of primary THA for osteoarthritis, inflammatory arthritis, or hip dysplasia between the two populations.

Conclusion

The incidence of THA for AVN is significantly different between a tertiary referral center and the greater United States. Patient demographics, race, and behavioral risk factors are associated with the disparity. Orthopaedic surgeons should recognize the differences in THA indication between populations when counseling patients on treatments, outcomes, and the most current literature.

Inhospital Complications and Costs of Simultaneous Bilateral Total Knee Arthroplasty: The Case for Selection and Potential Cost Savings

BACKGROUND

Published comparisons between bilateral and unilateral total knee arthroplasties (TKAs) remain biased, as most patients undergoing bilateral TKA are prescreened and healthier than average patients having unilateral procedures. Our objectives were to compare postoperative complications and resource utilization of patients having simultaneous bilateral TKAs with similar patients having unilateral procedures.

METHODS

The Nationwide Inpatient Sample (NIS) database was used to identify patients undergoing primary elective TKA from 2002 to 2011. A total of 4,445,263 patients were identified. Of these, 190,783 (4%) were having same-day bilateral procedures. Patients with staged bilateral TKA during the same hospitalization were excluded. Complications and costs were compared to a matched cohort of patients having unilateral procedures. This cohort was matched based on age, gender, and 30 comorbid-defined elements in the NIS.

RESULTS

A total of 172,366 (90%) simultaneous bilateral procedures were matched 1:1 to patients with unilateral procedures for the adjusted analysis. Patients with bilateral procedures were at an increased risk for many complications including postoperative anemia (OR: 2.3; 95% CI: 2.2-2.3, P < .001), cardiac (OR: 2.1; 95% CI: 2.0-2.3, P < .001), and inhospital mortality (OR: 3.3; 95% CI: 2.6-4.3). These patients also incurred in higher hospital costs ($19,343 vs $12,852, P < .001) and were discharged more commonly to a rehabilitation facility (70% vs 32%, P < .001).

CONCLUSION

Patients undergoing simultaneous bilateral TKA are at an increased risk of developing important postoperative complications and mortality compared with unilateral cases. These data highlight the importance of patient selection and optimization for bilateral TKA and potential cost savings.

Time-Driven Activity-Based Costing in Preoperative Tasks for Total Hip and Knee Arthroplasty

BACKGROUND

Substantial work in the preoperative phase of total hip arthroplasty (THA) and total knee arthroplasty (TKA) is unaccounted for in current Relative Value Scale Update Committee methodology. A Time-Driven Activity-Based Costing (TDABC) analysis allows for an accurate assessment of the preoperative costs associated with total joint replacement surgery.

METHODS

The mean time that clinical staff members spent on preoperative tasks per patient was multiplied by the hourly salary. Clinical staff members included orthopedic surgeons, nurse practitioners or physician assistants, nurses, medical assistants, and surgical coordinators. Mean time spent on preoperative tasks was obtained from the most recent literature. Salaries were obtained from the nationwide database provided by Glassdoor Inc.

RESULTS

Total time spent among clinical staff involved in preoperative tasks for each arthroplasty patient was 8.45 hours (2.96-13.94). Total TDABC was calculated to be $348.17 (132.46-562.64). Accounting for preoperative tasks, the TDABC for TKA/THA increases from $13321.5 to $13669.67. Preoperative tasks are composed of 2.6% of total TKA/THA TDABC. In 2020, an estimated $544,189,710 of preoperative TKA/THA work was completed.

CONCLUSION

Surgeons, providers, and ancillary staff involved in THA/TKA spend a cumulative preoperative work time of approximately 8.5 hours per patient, which equates to $348.17 that is currently unaccounted for in Relative Value Scale Update Committee methodology.

Increased Morbidity With Diagnosis and Treatment of Pulmonary Embolism After Total Joint Arthroplasty: A Matched Control Analysis of 30,000 Patients

BACKGROUND

Currently, the risks associated with the diagnosis of pulmonary embolism (PE) and subsequent treatment are not well known. The purpose of our study is to quantify the specific in-hospital complications and resource utilization of patients with PE following total joint arthroplasty when compared to a matched cohort.

METHODS

The Nationwide Inpatient Sample database was used to identify patients undergoing primary hip and knee arthroplasty from January 1993 to December 2008. PE was determined using International Classification of Diseases, Ninth Revision, Clinical Modification codes. In-hospital complications, costs, and length of stay for patients with PE were compared to patients without PE, matched on the basis of age, gender, procedure (total hip arthroplasty vs total knee arthroplasty), year of surgery, morbid obesity, and all 28 comorbid-defined elements of the Elixhauser Comorbidity Index.

RESULTS

Of 8,634,038 procedures, 30,281 (0.4%) patients had a PE after total joint arthroplasty. In total, 29,917 (98%) were matched one-to-one with patients without PE. Patients with PE had a substantially higher risk of all postoperative in-hospital complications: deep vein thrombosis (odds ratio [OR] 17), peripheral vascular (OR 34), hematoma (OR 3.7), and gastrointestinal bleeding (OR 7.0) (all P < .001). Mortality was significantly higher in patients with PE compared to patients without PE (3.4% vs 0.1%, OR 30), along with total hospital costs, lengths of stay, and rates of discharge to rehabilitation facilities.

CONCLUSION

After controlling for comorbidities patients with PE have a significantly higher risk for complications including in-hospital mortality and higher hospital costs when compared to patient without PE.

Perioperative Complications in Patients With Inflammatory Arthropathy Undergoing Total Hip Arthroplasty

BACKGROUND

Limited information exists comparing the short-term complications of the different inflammatory arthropathies (IAs) after total hip arthroplasty (THA). Our objectives were to (1) compare perioperative complications and (2) determine the most common complications between the different IA subtypes compared with patients with osteoarthritis (OA) undergoing primary THA.

METHODS

The Nationwide Inpatient Sample was used to identify 2,102,238 patients undergoing elective, unilateral THA between 2002 and 2011. Of these, 86,671 (4%) had an IA, including rheumatoid arthritis (RA), psoriatic arthritis, juvenile idiopathic arthritis (JIA), ankylosing spondylitis (AS), and systemic lupus erythematosus (SLE). Preoperative diagnosis, comorbidities, and postoperative complications were determined using International Classification of Disease Clinical Modification version 9 codes. The prevalence of in-hospital medical and orthopedic complications was compared between patients with an IA and OA.

RESULTS

When compared with patients with OA, patients with RA, JIA, SLE, and AS had significantly more inpatient medical and orthopedic complications immediately after THA (P < .01). Patients with JIA had the highest orthopedic complication rate (2.8%). Specific orthopedic complications by subtype included wound dehiscence for RA and AS periprosthetic fractures for JIA and increased mortality for SLE patients. There were no significant differences in medical or orthopedic complications seen in patients with psoriatic arthritis.

CONCLUSION

Differences exist in postoperative inpatient medical and orthopedic complications among patients with different types of IAs after THA. Our results point out the importance of preoperative optimization in patients with IA and monitoring for selective postoperative complications.

Total Joint Arthroplasty: A Granular Analysis of Outcomes in the Economically Disadvantaged Patient

BACKGROUND

Poor patients experience more serious complications and worse outcomes after surgery than higher-income patients. Our objective was to study detailed patient sociodemographic characteristics and preoperative/postoperative patient-oriented outcomes in economically disadvantaged and non-economically disadvantaged primary total joint arthroplasty patients.

METHODS

From a consecutive series, 213 economically disadvantaged patients and 1940 non-economically-disadvantaged patients were statistically analyzed. Baseline sociodemographic characteristics and pain visual analog scale, Quality of Well-Being Index 7, Short Form 36, and Western Ontario and McMaster Universities Arthritis Index scores recorded before and after surgery were compared between both groups controlling for baseline differences. Minimum follow-up was 1 year.

RESULTS

Economically disadvantaged patients were significantly younger, more likely to be disabled, and had worse preoperative and postoperative scores.

CONCLUSION

When compared with non-economically disadvantaged patients, economically disadvantaged patients consistently had lower function and worse quality of life before and after total joint arthroplasty.

Medicaid payer status is associated with in-hospital morbidity and resource utilization following primary total joint arthroplasty

BACKGROUND

Previous reports suggest that there are major disparities in outcomes following total joint arthroplasty among patients with different payer statuses. The explanation for these differences is largely unknown and may result from confounding variables. The Affordable Care Act expansion of Medicaid coverage in 2014 makes the examination of these disparities particularly relevant.

METHODS

The Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample (NIS) database was used to identify patients who had undergone primary hip or knee arthroplasty from 2002 through 2011. Complications, costs, and length of hospital stay for patients with Medicaid were compared with those for non-Medicaid patients. Each Medicaid patient was matched to a non-Medicaid patient according to age, sex, race, type of total joint arthroplasty, procedure year, hospital characteristics, smoking status, and all twenty-nine comorbidities defined in the NIS-modified Elixhauser comorbidity measure.

RESULTS

It was determined that 191,911 patients who underwent total joint arthroplasty had Medicaid payer status (2.8% of the entire total joint arthroplasty population), and 107,335 (56%) of these Medicaid patients were matched one to one to a non-Medicaid patient for all variables for the adjusted analysis. After matching, Medicaid patients were found to have a higher prevalence of postoperative in-hospital infection (odds ratio [OR], 1.7; 95% confidence interval [CI], 1.3 to 2.1), wound dehiscence (OR, 2.2; 95% CI, 1.4 to 3.4), and hematoma or seroma (OR, 1.3; 95% CI, 1.2 to 1.4) but a lower risk of cardiac complications (OR, 0.7; CI, 0.6 to 0.9). The length of the hospital stay was longer, total cost was higher, and discharge to an inpatient facility was more frequent for patients with Medicaid status (p < 0.01).

CONCLUSIONS

Compared with non-Medicaid patients, Medicaid patients have a significantly higher risk for certain postoperative in-hospital complications and consume more resources following total joint arthroplasty even when the two groups have been matched for patient-related factors and comorbid conditions commonly associated with low socioeconomic status. Additional work is needed to understand the complex interplay between socioeconomic status and outcomes, to ensure appropriate resources are allocated to maintain access for this patient population, and to develop appropriate risk stratification.

Relative head size increase using an anatomic dual mobility hip prosthesis compared to traditional hip arthroplasty: impact on hip stability

Smaller head sizes and head/cup ratios make cups smaller than 50mm and larger than 58mm, more prone to dislocation. Using computer modeling, we compared average head sizes and posterior horizontal dislocation distance (PHDD) in two 78-patient matched cohorts. Cup sizes were small (≤50mm) or large (≥58mm). The control cohort had conventional fixed bearing prostheses, while the experimental cohort had anatomical dual mobility (ADM) hip prostheses. ADM cups have larger average head sizes and PHDD than traditional fixed bearing prostheses by 11.5mm and 80% for cups ≤50mm, and 16.3mm and 90% for cups ≥58mm. Larger head sizes and increased head/cup ratio may allow the ADM prosthesis to reduce the incidence of dislocation.

Age as an independent risk factor for postoperative morbidity and mortality after total joint arthroplasty in patients 90 years of age or older

The population of patients over 90 years of age has experienced the fastest growth in recent years. The number of primary total joint arthroplasties (TJA) has also been increasing. Our objectives were to examine in-hospital morbidity, mortality and resource consumption following primary TJA in patients older than 89 years at the national level. Nationwide Inpatient Sample was used to identify 8,340,167 patients who underwent TJA between 1993 and 2008, 58,355 (0.7%) were 90 years of age or older. Older patients were at higher risk of developing cardiac (OR 2.5; 95% CI 2.4-2.6), neurological (OR 2.1; 95% CI 1.8-2.4), respiratory complications and higher risk of mortality (OR 11.5; 95% CI 10.93-12.1) after controlling for baseline comorbidities. Age is an independent risk factor for postoperative complications and mortality. Our data can be used to educate patients on the risks before undergoing primary TJA and aid physicians in assessing and adjusting perioperative risk.

Depression is associated with early postoperative outcomes following total joint arthroplasty: a nationwide database study

The purpose of this study was to assess the incidence of the diagnosis of depression and determine the impact of this diagnosis on early postoperative outcomes following total joint arthroplasty (TJA). Multivariate analysis of the Nationwide Inpatient Sample database was used to compare the association of depression with inhospital morbidity, mortality, length of stay, and hospital charges following TJA. The rate of diagnosis of depression in the arthroplasty population was 10.0%. Patients with depression were significantly more likely to be white, female, and have Medicaid as a primary payer (all P<0.05). Depression was associated with a greater risk of post-operative psychosis (OR = 1.74), anemia (OR = 1.14), infection (OR = 1.33), and pulmonary embolism (OR 1.20), and a lower risk of cardiac (OR = 0.93) and gastrointestinal complications (OR = 0.80). Depression was not associated with in-hospital mortality. Depression appears to impact early postoperative morbidity after TJA, a finding which is important for patient counseling and risk adjustment.

Primary total knee arthroplasty in patients with fibromyalgia

No data on the results of total knee arthroplasty (TKA) in patients with fibromyalgia have been published. The purposes of this study were to review a cohort of patients with fibromyalgia undergoing TKA to determine the level of postoperative pain and satisfaction with the surgery, the incidence of postoperative surgical complications, and revision rates and their relationship to TKA design. One hundred ten patients with fibromyalgia (141 knees) who underwent primary TKA between 1990 and 2001 were studied. The average age was 64 years (range, 39-86 years), and the average follow-up was 7 years (range, 2-16 years). Forty-five knees were cruciate retaining, and 96 had a posterior stabilized design. Clinical outcome was assessed using the Knee Society Knee Score and satisfaction regarding the results of the procedure. Postoperative surgical complications and reoperations were obtained from the registry. Sixty-two patients (44%) continued with some pain after TKA. Eighty-five patients (82%) were satisfied with the results. The most common complications were arthrofibrosis and symptomatic instability. The revision rate was 6% (8 knees). Survivorship free from revision at 7 years was 89% for cruciate retaining knees and 98% for posterior stabilized knees. Patients with fibromyalgia undergoing primary TKA have a high prevalence of complications and pain. Despite continued pain, the majority of patients were satisfied with the results and reported improvements after TKA. This data should be used to counsel patients with fibromyalgia preoperatively regarding limited goals with respect to pain relief and suggests that a multimodal individualized treatment program may be necessary to achieve optimal outcomes in patients with fibromyalgia.

Patellar meniscus in total knee arthroplasty

Twenty-four clinically successful, autopsy retrieved porous-coated anatomic total knee arthroplasty (TKA) specimens were evaluated to determine the structure and function of the patellar meniscus. Mean implant duration was 76 months (range: 11-135 months). Histological examination showed the patellar meniscus to be composed of dense fibrous tissue with scattered regions of chronic granulomatous response to polyethylene debris. Patellar wear and polyethylene exposed patellar surface area were correlated with implant duration (r = 0.47, P = .03; r = 0.52, P = .06). Postoperative patellar tilt was also associated with patellar component wear (r = 0.64, P = .03). No other clinical measures were significantly associated with patellar wear or exposed surface area. Additional research is needed to determine what role, if any, the patellar meniscus plays in TKA outcomes.

Postdischarge costs in arthroplasty surgery

Postdischarge costs associated with primary arthroplasty surgeries have received limited attention in the literature. Our objective was to identify the costs incurred after discharge in primary arthroplasty and to estimate annual postdischarge expenditures in the United States. A cohort of 136 patients who underwent primary arthroplasty was studied. Comprehensive rehabilitation unit (CRU) and home care (HC) costs were obtained. The National Hospital Discharge Survey 2003 data were used to model the national discharge cost estimates. Local patient-oriented outcome was also compared in the patients discharged to CRU vs HC. Total costs were significantly lower in patients discharged directly to home vs those sent to the CRU and who subsequently received HC ($2405 vs $13435, P < .001); both patient groups experienced similar quality of life improvements. An estimated $3.2 billion is spent annually on postsurgical rehabilitation after arthroplasty. Postdischarge costs are significantly higher for patients going to a CRU vs those discharged home; yet, both groups had comparable short-term outcomes.