RR-PL-0902

Thursday 10:00, Palau de Congressos, Hall 2, Room A

SAGITTAL PLANE LUMB0FEMORAL MOTION IN HEALTHY OLDER-AGED SUBJECTS  Tully E, Stillman B, Galea M, Matthews B.; The School of Physiotherapy, The University of Melbourne, Australia. PURPOSE: To clarify the pattern of combined hip with lumbar spine motion occurring during active full range unilateral hip-knee flexion in healthy older-aged subjects. RELEVANCE: The nature of combined hip and lumbar spine motion during various lower limb movements appears not  to have been previously studied in older-aged adults. Increased knowledge of normal hip and lumbar spine flexion and extension during functional activities such as stepping up a high step or pulling on a sock will provide clinicians with an improved basis for determining and treating abnormal movement patterns;  for example as in the setting of realistic rehabilitation goals for older subjects with degenerative joint disease affecting the hip or lumbar spine. SUBJECTS: 57 healthy physically-active 60-84-year-old subjects (37 females, 20 males) with a mean BMI of 26.9 participated in this study. METHODS: Light-reflective reference markers were attached to the skin over the spine, lateral aspect of the pelvis and right lower limb according to an improved model for videoanalysis of sagittal hip and spinal motion (Tully and Stillman 1995). From upright standing subjects flexed the right knee towards the ipsilateral shoulder at a comfortable (self- selected) speed. The reference marker locations were computer digitised from videotaped records of the test movement. ANALYSES: The angular data data for all subjects during the flexion (upward) and extension (downward) phases was standardized relative to the normalized total movement. Intraclass correlations were used to investigate the movement symmetry between the flexion and extension phases. RESULTS: These subjects had an average 121 (SD 13) degrees total hip-lumbar flexion comprising 86 degrees hip flexion and 35 degrees lumbar flexion. The hip and lumbar spine moved concurrently throughout the flexion and extension  phases. The relative contribution of the lumbar spine to the movement increased almost linearly during the flexion phase whereas it was greatest at the beginning and end of the extension phase. Those subjects with above-normal BMI had less hip flexion excursion by an average 11.1 degrees, but not lumbar excursion. CONCLUSIONS: Full range active hip-knee flexion in physically-active older-aged subjects involves concurrent lumbar flexion that contributes approximately 30% of the total movement. The commonly cited 120 degrees for normal full range hip flexion represents the sum of hip and lumbar flexion rather than flexion of the hip joint per se. No significant differences were found in hip-lumbar kinematics for these subjects compared with data held for younger-aged subjects.