Joint position study design.
The 3 arms of this comparison study were link and do not remove links (arm 1), link period followed by an unlinked period (arm 2), and control, that is, never linked (arm 3). Link configurations were neutral (EN), flexed (EF), or rotated (ER).
Control rats had SAU implants that were never linked (CSAU) or had sham SAU implant surgeries (CSURG). Radiographs were obtained for comparison between linked animals (R Linked), unlinked animals (R Unlinked), and never-linked or sham control animals (R Control).
Seven equivalent periods were examined in arm 3. These were homologous to the 1- to 16-week link periods with a “*to 20 weeks” period for comparison with the 8-weeks linked plus 12-week unlinked rats in arm 2. The animal counts reported in this figure are explained in the text.