Copyright © 2005 by The Journal of Bone and Joint Surgery, Inc.

Commentary & Perspective

Commentary & Perspective on
"Hospital Resource Utilization for Primary and Revision Total Hip Arthroplasty"
by Kevin J. Bozic, MD, et al.

Commentary & Perspective by
William L. Healy, MD*,
Lahey Clinic Medical Center, Burlington, Massachusetts

Prior cost identification studies for primary and revision total hip arthroplasty have suggested, if not proved, that hospital resource utilization and hospital cost for revision total hip arthroplasty is substantially higher than for primary total hip arthroplasty1-5. In their paper, "Hospital Resource Utilization for Primary and Revision Total Hip Arthroplasty," Bozic et al. have elevated the economic analysis of the hospital cost of reconstructive hip surgery to a new level. They clearly demonstrate that at the University of California - San Francisco Medical Center, revision total hip arthroplasty consumes more hospital resources and generates more hospital cost than does primary total hip replacement. In 2005, it is time for health-care policy makers and health-care payers to recognize that these economic observations have profound implications regarding incentives and disincentives for hospitals to offer revision hip replacement operations to patients.

The careful methodology of this study contributes to the validity of the conclusions. The retrospective cohorts were specifically stratified by CPT (current procedural terminology) codes into primary and revision hip replacement study groups. Detailed demographic, clinical, radiographic, intraoperative, economic, and outcome data were available for both study groups. The authors implemented the All-Patient Refined Diagnosis-Related Group Severity of Illness (APR-DRG SOI) Index to stratify the preoperative health and comorbidity of the patients. The economic data studied reflected true hospital cost information, and the medical care component of the Consumer Price Index was used to adjust all costs to 2003-dollar values.

The results confirm the authors' first hypothesis that "hospital resource utilization for revision total hip arthroplasty is significantly higher than that for primary total hip arthroplasty." Patients who had revision hip replacement operations were older, sicker, and had a greater prevalence of osteolysis and bone loss. Revision operations were associated with longer operative time, more use of bone graft, increased rates of complication, longer hospital stay, higher rate of discharge to a post-acute-care facility, increased rate of hospital readmission, and higher hospital costs. Consistent with prior studies on this topic, the largest resource utilization and cost occurred in the operating room6. Furthermore, the authors identified patient characteristics associated with increased resource utilization and increased cost. Sicker patients with APR-DRG SOI Grade III and IV consumed more resources at higher cost for both primary and revision hip replacement operations. For revision total hip arthroplasty, osseous deficiency and periprosthetic fracture were associated with increased resource utilization and increased hospital cost.

The information in this study will be of interest to health-care policy makers and health-care payers. The authors warn us that economic losses incurred by hospitals that perform revision total hip arthroplasty provide a strong disincentive to provide this service. As margins for all hospital services decrease, hospitals may not be able to afford to provide elective revision hip replacement operations at an economic loss. This information should be disturbing to health-care policy makers who are concerned about patient access to reconstructive hip procedures. This study provides compelling data to increase hospital reimbursement for revision total hip arthroplasty.

The Federal Government, through the Medicare program, pays for 60% of reconstructive hip operations in this country. Hospitals are reimbursed the same payment for primary and revision hip replacement operations through DRG 209, which is one of the highest expense categories for CMS (The Centers for Medicare and Medicaid Services). The population of the United States is increasing and aging, and Medicare expenditures for DRG 209 are increasing as the prevalence of primary and revision total hip arthroplasty operations increase. Furthermore, these procedures and Medicare DRG 209 expenses are expected to continue to increase over the next three decades7. To maintain access to revision total hip arthroplasty for Medicare patients and to fairly reimburse hospitals for this service, CMS should use the data provided by Bozic et al. to stratify DRG 209 hospital payment and increase hospital reimbursement for revision total hip arthroplasty. This has been done previously for spinal fusion and coronary artery bypass graft operations.

Medicare policy makers should be advised to avoid the simplistic response to split the total expenditure for DRG 209 into a primary-hip-replacement expense line and a revision-hip-replacement expense line. An exercise of so-called "zero sum budgeting" would reduce the hospital reimbursement for primary total hip arthroplasty, which has had decreasing hospital margins for several years as hospital payment for primary total hip arthroplasty has not kept up with the increased cost to deliver primary total hip arthroplasty. Rather, CMS budget makers should plan to increase payment for revision total hip arthroplasty commensurate with the increased resources consumed and the increased cost to deliver the service.

There is more work to be done. The authors can demonstrate that the significant results in their urban, high-volume, academic medical center are applicable to community hospitals, suburban and rural hospitals, and hospitals with variable volume. They can also use their data to establish a simple, readily available tool for stratifying severity of illness—the APR-DRG SOI index is not a mainstream tool for clinical stratification in 2005. Can the American Society of Anesthesiologist's Score be substituted for the APR-DRG SOI? Can patient age plus one or more specific clinical diagnoses be substituted for the APR-DRG SOI? Will the APR-DRG SOI index gain greater applicability in the next few years? If hospital payment is to be increased for revision total hip arthroplasty, clear, well-defined, and reproducible criteria must be used to establish the indications for increased payment.

This evaluation of hospital resource utilization and hospital cost for total hip arthroplasty does not include professional resource utilization, professional cost, or professional payment for hip replacement operations. From 1991 to 2004, as DRG 209 reimbursement to hospitals for primary and revision total hip arthroplasty increased 16%, Medicare reimbursement to orthopaedic surgeons for reconstructive hip operations decreased 35%8. This trend should disturb health-care policy makers, who must be concerned about physician manpower and patient access to service. This reduction in professional payment for hip-replacement operations has been associated with fewer orthopaedic surgery residents choosing to pursue postgraduate fellowship training in adult reconstruction orthopaedic surgery. While professional reimbursement for revision total hip arthroplasty is slightly higher than reimbursement for primary total hip arthroplasty, the increase is minimal, and it is inadequate to compensate for the increased professional hours and expertise required with revision hip replacement. Revision total hip arthroplasty is generally associated with more extensive preoperative evaluation, increased operative time, higher intensity of work in the operating room, increased postoperative complications, and increased professional risk. When CMS policy makers and budget builders reevaluate the hospital costs and hospital payment of primary and revision total hip arthroplasty, they should also consider the professional cost and professional payment of reconstructive hip surgery. Manpower issues are of concern to all health-care policy makers, and the economics of primary and revision total hip arthroplasty in 2005 will contribute to a worsening manpower problem for reconstructive hip surgeons.

Bozic et. al. have clearly demonstrated that revision total hip arthroplasty consumes more hospital resources and generates more hospital costs than primary total hip arthroplasty at their hospital. Health-care policy makers and health-care payers should use these data to justify increasing hospital and professional payment for revision total hip arthroplasty. This will fairly compensate hospitals and surgeons who provide these surgeries and protect access for patients who require these services.

*The author did not receive grants or outside funding in support of the research or preparation of this manuscript. He did not receive payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, educational institution, or other charitable or nonprofit organization with which the author is affiliated or associated.

References

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