Relationship between low back pain and lumbar multifidus size at different postures.
Lee SW, Chan CK, Lam TS, Lam C, Lau NC, Lau RW, Chan ST. Relationship between low back pain and lumbar multifidus size at different postures. Spine (Phila Pa 1976). 2006 Sep 01; 31(19):2258-62.