Leivseth, Gunnar MD, PhD ; Braaten, Sjur MD; Frobin, Wolfgang Dr; Brinckmann, Paul Prof. Dr.
This study's objectives were to document the rotational and translational range of segmental motion of patients instrumented with ProDisc II prostheses in the lumbar spine, compare motion between instrumented and untreated adjacent segments with respect to a normative database and discuss potential causes of the low range of rotational motion observed after instrumentation with a Prodisc II prosthesis. The authors conclude that disc replacement in the lumbar spine by a ProDisc II implant fails to restore normal segmental rotational motion in the sagittal plane, specifically at levels L4-L5 and L5-S1. As segmental motion of the untreated segments was lower than normal as well, though not quite as conspicuous as that of instrumented segments, adaptation of soft tissue taken place during the preoperative symptomatic time period is conjectured to cause the observed motion deficit. Postoperative physical therapy might be considered if restoration of a normal range of rotational motion is desired.
Spine. 31(15):1726-1733, July 1, 2006