Fig. 4.

Flowchart illustrating the patient recruitment and retention in this randomized controlled trial. In the motion group, no patients were lost to follow-up and one subject had conversion to an arthrodesis between the fifty-two and 104-week follow-up visits. In the fixed (non-motion) group, one subject dropped out prior to the T1 visit, one subject dropped out after the twelve-month return visit, and one subject dropped out after the T52 visit. The latter two patients moved out of state. In the fixed (non-motion) group, three additional patients had arthrodesis surgery, one before the T52 visit and two between the T52 and T104 visits.