Abstract: This paper investigated the changes of related muscle characteristics and their clinical significance in patients with non-specific low back pain (NLBP) by musculoskeletal ultrasound, superb microvascular imaging (SMI) and real-time shear wave elastography (SWE). 200 patients with NLBP were selected as the NLBP group, and 100 healthy volunteers (without signs and manifestations of lumbar pain) were selected as the control group. SMI, SWE technology and musculoskeletal ultrasound were used to determine the injury, elastic modulus and thickness of external oblique muscle, transverse abdominis muscle, iliopsoas muscle, erector spinae muscle and multifidus muscle of the two groups. All NLBP patients received rehabilitation treatment, and the changes of elastic modulus and thickness of muscle groups were observed before and after rehabilitation treatment. The thickness measurement and elastic modulus of external oblique muscle, transverse abdominis muscle, iliopsoas muscle, erector spinae muscle and multifidus muscle in NLBP group were lower than those in control group (P<0.05). After SMI examination, the positive rate of external oblique muscle, erector spinae muscle and multifidus muscle injury in NLBP group were all higher than those in control group (P<0.05). The thickness measurement, thickness and elastic modulus of external oblique muscle, transverse abdominis muscle, iliopsoas muscle, erector spinae muscle and multifidus muscle in NLBP group after treatment were significantly higher than those before rehabilitation treatment (P<0.05). NLBP patients have muscle atrophy and poor muscle elastic strength, musculoskeletal ultrasound, SMI and SWE can effectively observe the changes of muscle injury, atrophy and elastic strength in patients, and quantify the rehabilitation situation.

Key words: musculoskeletal ultrasound, real-time shear wave elastography, non-specific low back pain (NLBP), elastic modulus, muscle thickness