Once-weekly oral medication with alendronate does not prevent migration of knee prostheses: A double-blind randomized RSA study.
OBJECTIVE
Early migration of joint replacements is an effect of poor fixation and can predict late loosening. By reducing the bone resorption after implantation of a joint replacement, it should be possible to enhance the initial fixation of the implant. We studied the effect of once-weekly treatment with alendronate after knee replacement.


METHODS
We recruited 60 patients (60 knees) with gonarthrosis who were scheduled for a total knee replacement. They were operated on with identical implants and uncemented fixation. 30 patients were treated with a bisphosphonate (alendronate) and 30 patients underwent placebo treatment. The treatment started postoperatively and continued on a weekly basis for 6 months. The fixation of the implants was measured with repeated radiostereometry for 2 years.


RESULTS
There was no difference in migration of implants between the two groups.


CONCLUSIONS
With uncemented fixation of knee implants, no benefit of once-weekly treatment with alendronate, starting postoperatively, could be seen during a 2-year follow-up period.
Hansson
Ulrik
U
Department of Orthopedics, Lund University Hospital, Lund, Sweden. ulrik.hansson@med.lu.se
Toksvig-Larsen
Sören
S
Ryd
Leif
L
Aspenberg
Per
P
D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D019386:Alendronate / Q000008:administration & dosage*; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D015519:Bone Density / Q000187:drug effects; D050071:Bone Density Conservation Agents / Q000008:administration & dosage*; D016723:Bone Remodeling / Q000187:drug effects; D001862:Bone Resorption / Q000000981:diagnostic imaging; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery; D011475:Prosthesis Failure; D011859:Radiography
D050071:Bone Density Conservation Agents; D019386:Alendronate