Do primary care physicians order more MRI for knee pain than orthopedic surgeons? Or is it the other way around?
A new article published in the Journal of Bone and Joint Surgery examines how orthopedists order MRI for knee pain compared to primary care physicians. There were 1,592 patients who met the criteria for the study. The patients went to an orthopedic outpatient office between Jan. 1, 2010 and Dec. 31, 2011 for unspecific knee sprains and strains.
There were 747 patients referred by primary care physicians and 845 patients initially evaluated by orthopedic staff.
Here are five key notes:
1. The orthopedic surgeons and primary care physicians ordered MRI at almost identical rates. The MRI-ordering rate was 25 percent for orthopedic surgeons and 24.8 percent for primary care physicians.
2. There was a difference in how many MRI turned into arthroscopic interventions; 41.2 percent of the MRI ordered by orthopedic surgeons resulted in arthroscopic interventions, compared to 31.4 percent of the primary care physicians.
3. The orthopedic surgeons ordered MRI for patients who were more likely to benefit from arthroscopic intervention. The patients had these general demographics:
• Younger patients — 45.1 years, compared with 56.5 years for PCPs
• Acute symptoms — 39.3 percent versus 22.2 percent for PCPs
• History of trauma — 49.3 percent versus 36.2 percent for PCPs
4. The primary care physicians were more likely to order MRI for older patients with substantial osteoarthritis and were likely to undergo total knee arthroplasty.
5. The researchers concluded, "Our data support the hypothesis that orthopedic surgeons obtain MRIs of the knee with more discretion than non-orthopedic providers."