Characteristics of Back Muscle Strength in Patients with Scheduled for Lumbar Fusion Surgery due to Symptomatic Lumbar Degenerative Diseases

Study Design Cross sectional study. Purpose To evaluate characteristics of back muscle strength in patients scheduled for lumbar fusion surgery. Overview of Literature Little is known regarding muscle strength in patients with symptomatic lumbar degenerative diseases who require fusion surgery. Methods Consecutive 354 patients scheduled for posterior lumbar interbody fusion due to symptomatic degenerative diseases were approached for participation. 316 patients were enrolled. Before surgery, muscle strength was assessed by measuring maximal isometric extension strength at seven angular positions (0°, 12°, 24°, 36°, 48°, 60°, and 72°) and mean isometric strength was calculated. The Oswestry Disability Index (0-100) and visual analogue scale (0-100) for back pain were recorded. Muscle strength was compared according to gender, age (0.05). Isometric strengths showed significant, but weak, inverse correlations with age and Oswestry Disability Index (r