In vivo 3D rotational segmental spinal kinematics in low back pain patients

Three-dimensional (3D) dynamic segmental spinal kinematics were studied in low-back pain patients using infrared light emitting diodes mounted on bilateral percutaneous pedicle screws in one lower lumbar vertebra and the sacrum. Data were collected whilst four subjects performed a number of activities of daily living including bending in all planes. Three subjects showed limited motion (instrumented between LA or L5 and the sacrum), and one subject showed a range of motion approximately one-third of healthy young normal subjects (instrumented between L5 and the sacrum). Standing to flexion data for this patient exhibited motion suggestive of clinical instability.