I had a TKR in both knees almost four years ago and have been suffering from persistent pain and stiffness for at least three years and was diagnosed with arthritis fibrosis. A good friend of mine is a physical therapist and she has been researching this condition. She recently discovered a trial that dealt with persistent pain following TKR:
Arthroplasty
Persistent pain after total knee arthroplasty (TKA) has been speculated to be a result of central sensitization5. The authors of 1 randomized controlled trial (RCT) found that, of 464 patients with primary osteoarthritis scheduled for elective TKA, 80 demonstrated signs of central sensitization6. These 80 patients were randomized to treatment with duloxetine (30 mg daily for 6 weeks) or no duloxetine (control group). The duloxetine group demonstrated significantly greater improvement from 2 to 12 weeks in all pain outcome measures assessed (p < 0.05). The 2 groups did not differ significantly with respect to adverse events6.

I presented this information to my family doctor and he has given me a prescription of duloxetine (Cymbalta) to try. Has anyone else tried this approach?