Knee and hip arthroplasty patients who were considered appropriate candidates for joint replacement surgeries fared better than those who were considered inappropriate candidates, according to new research seeking to identify the best criteria for total knee replacement (TKR) and total hip replacement (THR).¹

In the prospective, observational study of 1576 consecutive patients with diagnoses of OA on waiting lists to undergo THR or TKR, researchers employed the RAND appropriateness method, which combines expert opinion with available scientific evidence to create explicit appropriateness criteria. An appropriate procedure is defined as one in which "the expected health benefit exceeds the expected negative consequences by a sufficiently wide margin that the procedure is worth doing, exclusive of cost."²

The authors first performed a literature search to summarize the existing knowledge on the effectiveness and risks for THR and TKR in patients with osteoarthritis (OA). From this review, they compiled lists of mutually exclusive and clinically specific indications in which these surgeries may be performed. The final list contained 216 scenarios for THR and 624 for TKR. Scenarios included such variables as age, bone quality measured by x-ray, surgical risk, previous nonsurgical procedures performed, pain and functional limitation assessment, and need for mobility aids.

Ratings were based on a 9-point scale and were determined by two national panels: one that developed appropriateness criteria for THR and the other for TKR. The use of each procedure was considered appropriate if the panel's median rating was between 7 and 9 without disagreement and inappropriate if the value was between 1 and 3 without disagreement. The appropriateness of the procedure was considered uncertain if the median rating was between 4 and 6 or if panel members disagreed.

After researchers applied explicit appropriateness criteria using the RAND appropriateness method, to validate this criteria, patients then completed two questionnaires that measured health-related quality of life—the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)—both before the procedure and 6 months afterward.

Those patients who were considered appropriate candidates for surgery showed greater improvements in all three WOMAC domains—pain, functional limitation, and stiffness. Patients who were judged to be appropriate candidates and  underwent THR had greater improvements in the physical function, role–physical, bodily pain, and social function domains of the SF-36 than those judged to be inappropriate candidates (P <.001), the study showed. Appropriate candidates for TKR demonstrated greater improvement in the social function domain of the SF-36 after the procedure than those who were deemed inappropriate candidates (P = .004), but not in the other domains of functional status.

"These results suggest a direct relationship between explicit appropriateness criteria and better health-related quality-of-life outcomes after THR and TKR surgery, [and] our results support the use of these criteria for clinical guidelines or evaluation purposes," the researchers conclude.

One treatment doesn't work for everyone

Michael A. Mont, MD, director of the Center for Joint Preservation and Reconstruction at the Rubin Institute for Advanced Orthopaedics, Sinai Hospital, in Baltimore, Maryland, tells CIAOMed that "the main things that we look for in deciding who is an appropriate candidate for arthroplasty procedures is a combination of severe pain, pain affecting various quality of life issues, [and] pain that is not responsive to various nonoperative treatment methods for 6 months, coupled with the appropriate arthritis on x-rays."

Dr. Mont says that if there is no evidence of arthritis on x-rays, then something else is going on and the patient is not a candidate for TKR or THR. On the flip side," if there is severe arthritis on x-rays, but no pain limiting quality of life, it's inappropriate to perform THR or TKR."

That said, these are not one-size-fits-all criteria, Dr. Mont adds. "An older woman from Baltimore who relies on her car to get around and a woman from New York City who walks 10 to 15 miles a day can have the same pathology of their knee, but the woman from Baltimore does not need the surgery, while the lady from New York who wants to keep up with her walking does," he says. "You can't apply the same criteria to all people."

References

1. Quintana JM, Escobar A, Arostegui I, et al. Health-related quality of life and appropriateness of knee or hip joint replacement. Arch Intern Med. 2006;166:220-226.
2. Brook RH, Chassin MR, Fink A, et al. A method for the detailed assessment of the appropriateness of medical technologies.  Int J Technol Assess Health Care. 1986;2:53-63.