Impact of Back Muscle Functions, Spinal Range of Motion and Fear-Avoidance Beliefs on Disability in Chronic Non-Specific Low Back Pain

Background: Non-specific LBP is one of the most common conditions for which individuals seek the advice of a physiotherapist. Physical Therapists must be able to identify those attributes that contribute to Functional disability in patients with non specific LBP and recognize interventions that prevent or minimize the progression to chronicity.Methodology: 63 subjects (32 males and 31 females) suffering from non-specific chronic LBP were assessed for trunk extensor muscle endurance (using the modified Biering-Sorensen Test); trunk extensor muscle strength (using the back-and leg dynamometer); back muscle flexibility (using the sit and reach test); spinal range-ofmotion (using the universal goniometer and tape measure), Fear avoidance beliefs for physical activity & work ( Fear-Avoidance Beliefs Questionnaire) and functional disability (Revised Oswestry Low Back Pain Disability Questionnaire).Result and conclusion: Decreasing trunk extensor muscle endurance (r= -0.65, p= 0.0001), muscle strength (r= -0.44, p= 0.0004) and back muscle flexibility (r= -0.68, p= 0.0001) are significant factors leading to functional disability in LBA. Psychological factors i.e. fear-avoidance belief for physical activity (r=0.25, p= 0.0467) and fear-avoidance belief for work (r=0.31, p= 0.0140) were also found to be one of the major factors for increasing disability in non-specific low back pain. However, impact of spinal range-of-motion on disability was not significant.