Effects of Adding Tactile Stimuli to Verbal Instructions for Lumbar Multifidus Muscle Activation in Healthy Adults and Patients With Low Back Pain

Reduced lumbar multifidus muscle contraction has been observed in patients with low back pain (LBP). Currently, considerable evidence supports spinal stabilization exercises for treating LBP, including lumbar multifidus muscle activation exercises. Clinicians often apply a tactile stimulation on the muscle in addition to verbal instructions to ensure muscle activation. However, whether or not the addition of tactile stimulation would increase muscle activation has not been studied. Therefore, the investigators plan to use electromyography (EMG) to examine if addition of tactile stimulation to verbal instructions would increase lumbar multifidus muscle activation in healthy adults and patients with LBP.

The purpose of this study is to compare combined tactile stimulation and verbal instruction to verbal instruction only on lumbar multifidus muscle activation in asymptomatic healthy adults and in patients with LBP. The research hypothesis is that the lumbar multifidus muscle activation will be increased when the participants are given combined tactile stimulation and verbal instruction as compared to when the participants are given verbal instruction only.

Participants:

Eligible participants are English-speaking adults 18 years of age or older. Additional criteria for asymptomatic healthy adults include no existing LBP and no LBP in the past year. Additional criteria for patient participants include existing LBP near the L5-S1 level with an average pain intensity score ≥ 2/10 in the past 24 hours (numeric pain rating scale of 0-10, 0 being no pain, 10 being unbearable pain). Exclusion criteria for all participants include previous low back surgery, systemic joint disease (e.g. rheumatoid arthritis), cancer of the lower quadrant, neurological disorders, allergic reaction to ultrasound gel, or inability to obtain testing positions (prone lying).

The investigators plan to enroll 20 asymptomatic healthy adults, and 20 patients with LBP. Potential participants will be recruited from the local community (including but not limited to Texas Woman's University - Dallas) via flyers. The flyers will be posted at the TWU - Dallas campus and other community centers with approval. Participants who are interested in taking part in the study will be asked to call investigators to schedule an appointment time for testing. The consent form will be presented at the beginning of the appointment.