The ability to test or exercise in a functional pattern is important because,
in real life activities, musculature other than the abdominals and erector
spinae are used to perform such tasks as lifting. The semi-standing posi-
tion, in which the seat is slightly reclined from horizontal, allows for hip
involvement and a range of motion comprising both lumbar and sacral
movement. This position simulates an upright standing position with
respect to the musculature that contributes to this posture but reduces
some of the compressive forces acting at the low back. Past history has
demonstrated that this position is comfortable for the patient and results
in greater compliance to the rehabilitation program. Many clinicians con-
sider the semi-standing position effective for functional assessment of
lower back extension/flexion motion. A necessary degree of stabilization
is achieved through the use of a cervical support, thoracic support, chest
harness, scapula pad, pelvic support, thigh strap, and foot cuffs.
Effective lumbar isolation, on the other hand, is achieved by placing the
patient in the "seated compressed" position and using the femurs to
immobilize the pelvis. This fixation is accomplished by positioning the
patient in the seat against a specially designed sacral pad and securing
him/her into this surface with the lower extremity compression pad.
Laterally, the patient is secured by the contour of the pad. f course, all
the stabilization features noted for the semi-standing position are also
incorporated to ensure maximal stabilization. Range of motion should
be limited to that which is produced from the lumbar area.
When placed in the seated-compressed position with the seat slightly
inclined from horizontal, the patient maintains some degree of lordosis,
resulting in less deformation of the discs and reduced loads on the lum-
bar region. The sacral pad also helps to maintain this lordotic position
and reduced compression. Because of these factors, isolated lumbar test-
ing is very safe — especially when performed isometrically.
Numerous reasons for isolated lumbar testing have been recognized.
ne important factor stems from a research standpoint. As with joint
testing, the more isolated the motion and the better the stabilization, the
more reproducible the task. Because the movement is isolated the clini-
cian may be sure that the abdominals and erector spinae are being exer-
cised to full capacity with minimal contributions of hip, gluteal, and
other lower extremity musculature.
1. PARTS AND COMPONENTS
INTRODUCTION — 4—
