Clinical Prediction Rule for Clinical Lumbar Instability

Clinical identification of individuals with mechanical low back pain who would benefit from
a program of stabilization exercises has been a struggle for the physical therapy
profession. While changes in trunk muscle recruitment and motor control have been linked to
patients with chronic low back pain and hypothesized to be adaptations for spinal
instability, this has not been systematically established. However, a connection between
spinal instability, poor trunk motor control, and low back pain is plausible. The real
problem lies with the clinical identification of the subgroup of patients in either the
acute or chronic phases of low back dysfunction who would most benefit from this approach to
intervention.

In creating their preliminary clinical prediction rule, Hicks et al (2005), looked at many
variables including patient demographics and characteristics, hip and trunk motion, special
tests for instability, and functional measures of muscle performance. However, measures of
the performance of core stabilizing muscles and assessment of trunk dynamic control/
coordination were not included as potential variables. The aim of this study is to determine
if assessment of additional measures of trunk neuromuscular control will improve the ability
to identify patients with low back pain who successfully respond to trunk stabilization
exercises.

Inclusion Criteria:

1. duration of the current episode of low back pain less than 3 months,

2. average pain intensity over past 3 days at least 4 on an 11 point (0 = no pain, 10 =
worst pain ever) numeric pain rating scale,

3. no medical intervention for low back pain in last 6 months,

4. Oswestry score greater than 25%

Exclusion Criteria:

1. permanent structural spinal deformity (e.g., scoliosis)

2. history of spinal fracture or diagnosis of osteoporosis

3. diagnosis of inflammatory joint disease

4. signs of systemic illness or suspected non-mechanical LBP (i.e. spinal tumor or
infection)

5. previous spinal surgery

6. frank neurological loss, i.e., weakness and sensory loss

7. history of neurologic disease that required hospitalization,

8. active treatment of another medical illness that would preclude participation in any
aspect of the study or any lower extremity injury that would potentially alter trunk
movement in standing

9. leg length discrepancy of greater than 2.5 cm.

10. pregnancy

11. vestibular dysfunction