Pilot Case Control Study of Postural Sway and Balance Performance in Aging Adults with Degenerative Lumbar Spinal Stenosis

Abstract

Lumbar spinal stenosis (LSS), a degenerative disease encountered in adults > 65 years, is a leading cause of back and lower extremity pain, weakness, impaired sensation and balance. The purpose of this pilot study was to determine whether patients with LSS demonstrate increased postural sway and impaired balance, compared to healthy counterparts. Patients with varying severity of LSS and age and gender matched controls were recruited from a tertiary care hospital, yielding 6 case-control pairs. Subjects completed generic health status (SF-36), disease specific scales (LSS) and demographic forms. Medical comorbidities were extracted from medical records. Patients received a musculoskeletal examination and performed the Functional Reach (FR) and Timed "Up & Go" (TUG) tests. Stabilogram diffusion analysis (SDA) measured center of pressure (COP). Patients reported moderately impaired physical function, lumbar flexibility and walked with a slightly wider base of support. TUG scores did not differ across groups. Significantly limited FR scores indicated that patients had impaired dynamic balance and were at a greater risk of falls. SDA demonstrated no significant difference in sway for patients and controls; however, patients demonstrated significantly higher critical values for antero-posterior (AP) displacement than controls. Patients with LSS, even those with mild symptoms, demonstrate decreased function and balance, particularly in the AP direction. Physical examination measures and TUG are not adequate to assess balance impairments or risk of falls in these patients. Measures such as the FR and SDA may be useful in detecting the aspects of balance impairments perceived by patients.