The stability of three different cementless tibial components: A randomized radiostereometric study in 45 knee arthroplasty patients

Clodronate prevents prosthetic migration: A randomized radiostereometric study of 50 total knee patients

“…Most of the migration occurs during the first 6 weeks. It then continues at a gradually slower rate up to 1 year, whereafter most implants become stable (Ryd et al 1986, Nilsson et al 1991, Hilding et al 1995. In a large long-term study where 158 knees were followed by RSA up to 10 years, all cases that eventually loosened had shown continuous migration, but also a significantly larger migration as early as 6 months postoperatively .…”

“…Further, continuous migration is associated with inducible displacement, i.e., immediate motion between implant and bone on load (Hilding et al 1995). Since the tibial component of a knee prosthesis, or the cement, rests directly on bone postoperatively, inducible displacement suggests that the superficial layer of the bone has been resorbed and replaced by soft tissue.…”

Knee Joint Loading and Tibial Component Loosening

“…Seven patients had TKA on the opposite knee, four in the PCA group, two in the Tricon-M group and one in the Tricon stem group, all more than six months after the first operation. As we have previously reported (Hilding, Yuan and Ryd 1995), all 43 patients available at the two-year followup had good or excellent clinical results, with a mean HSS score of 88 (71 to 94). None showed complete radiolucent zones of 2 mm or more.…”

“…A standard RSA method is to express the motion as the vector-sum of motions of the marker that moved the most, recording magnitude but not direction to give maximum total point motion (MTPM). The RSA results for this group of patients have been published (Hilding et al 1995), and we found no statistically significant differences between the three designs of prosthesis for mean migration (MTPM) at two years; they were 1.3, 1.4 and 1.5 mm. Statistics.…”

“…Because there were no significant differences between the three different tibial components in these gait parameters, the previously reported RSA migration (Hilding et al 1995) or in demographical, clinical or radiological parameters, the groups were collapsed for all further analyses. In most patients with an initial varus deformity, TKA significantly reduced the frontal plane varus angle, the moment arm and the adduction moment.…”