Data from UMMS-led registry shows national norms for timing of hip and knee replacements

UMass Medical School Communications

March 07, 2014
David Ayers, MD
David Ayers, MD

New data from a federally funded research registry led by UMass Medical School has pinpointed “typical” patient pain and function scores at which most patients undergo joint replacement surgery. The data was gathered through more than 125 orthopedic surgeons on 15,000 joint replacement patients across the United States.

“This is the first time we’ve been able to quantify the point at which most patients and surgeons together make the decision to proceed with a total knee or hip replacement,” said David Ayers, MD, the Arthur M. Pappas, MD, Chair in Orthopedics, chair and professor of orthopedics & physical rehabilitation and director of the Musculoskeletal Center of Excellence. “We studied the typical orthopedic practice in the United States and found that we were able to statistically identify a point, based on a national sample of patients’ reported levels of pain and functional impairment, that surgeons offer surgery and patients decide to move forward.”

The uniformity of pain and function scores across such a wide population offers, for the first time, possible national benchmarks  that patients and surgeons can use in shared decision-making and for comparison to assess where a patient falls on a spectrum and whether they meet these national “norms” for the timing of surgery.

Surgeons participating in the research program called FORCE-TJR use a proprietary computerized system to collect standardized, validated patient reported outcomes questionnaires (PROs) pre- and post-surgery. The FORCE-TJR system allows knee or hip pain to be quantified and joint pain and stiffness (function) to be scored independently. Together, the data produces a combined physical composite score (PCS) for a patient’s level of pain and physical function.

The nationally recognized mean PCS score for an individual with no hip and knee pain or functional difficulty is 50. The FORCE-TJR study across 15,000 patients found that the typical PCS score for a patient at the point they decide to have joint replacement surgery is 32—nearly two standard deviations below the norm, representing significant pain and disability.

"PROs provide a valuable tool to guide physician and patient decision-making around the very difficult decision to proceed or not with a joint replacement," said Courtland Lewis, MD, physician in chief, Hartford Healthcare Bone & Joint Institute.

Physician use of PROs to guide patient care is a relatively new concept. Few orthopedic research programs and registries have collected standardized patient-reported outcomes (PROs) information, rather focusing on the performance of the actual implant device and the number of revision surgeries to define joint replacement success.

The FORCE-TJR database is expanding that notion to include PROs on pain relief and function as additional important measures of success.

FORCE-TJR surgeons consistently gather validated PROs from their patients pre- and post-surgery. On track to enroll more than 30,000 patients in the program, the FORCE-TJR database is the largest to provide measureable patterns of patient pain, function, mobility and other health indicators that can help patients and their physicians understand where they fall on a national spectrum of norms both pre- and post- joint replacement.

This data is among the first to be publicly released by the FORCE-TJR consortium.