The relationship between clinical examination measures and ultrasound measures of fascia thickness surrounding trunk muscles or lumbar multifidus fatty infiltrations: An exploratory study

Abstract

Patients with chronic low back pain (CLBP) exhibit remodelling of the lumbar soft tissues such as muscle fatty infiltrations (MFI) and fibrosis of the lumbar multifidus (LuM) muscles, thickness changes of the thoracolumbar fascia (TLF) and perimuscular connective tissues (PMCT) surrounding the abdominal lateral wall muscles. Rehabilitative ultrasound imaging (RUSI) parameters such as thickness and echogenicity are sensitive to this remodelling. This experimental laboratory study aimed to explore whether these RUSI parameters (LuM echogenicity and fascia thicknesses), hereafter called dependent variables (DV) were linked to independent variables (IV) such as (1) other RUSI parameters (trunk muscle thickness and activation) and (2) physical and psychological measures. RUSI measures, as well as a clinical examination comprising physical tests and psychological questionnaires, were collected from 70 participants with LBP. The following RUSI dependent variables (RUSI‐DV), measures of passive tissues were performed bilaterally: (1) LuM echogenicity (MFI/fibrosis) at three vertebral levels (L3/L4, L4/L5 and L5/S1); (2) TLF posterior layer thickness, and (3) PMCT thickness of the fasciae between subcutaneous tissue thickness (STT) and external oblique (PMCTSTT/EO), between external and internal oblique (PMCTEO/IO), between IO and transversus abdominis (PMCTIO/TrA) and between TrA and intra‐abdominal content (PMCTTrA/IA). RUSI measures of trunk muscle's function (thickness and activation), also called measures of active muscle tissues, were considered as independent variables (RUSI‐IV), along with physical tests related to lumbar stability (n = 6), motor control deficits (n = 7), trunk muscle endurance (n = 4), physical performance (n = 4), lumbar posture (n = 2), and range of motion (ROM) tests (n = 6). Psychosocial measures included pain catastrophizing, fear‐avoidance beliefs, psychological distress, illness perceptions and concepts related to adherence to a home‐based exercise programme (physical activity level, self‐efficacy, social support, outcome expectations). Six multivariate regression models (forward stepwise selection) were generated, using RUSI‐DV measures as dependent variables and RUSI‐IV/physical/psychosocial measures as independent variables (predictors). The six multivariate models included three to five predictors, explaining 63% of total LuM echogenicity variance, between 41% and 46% of trunk superficial fasciae variance (TLF, PMCTSTT/EO) and between 28% and 37% of deeper abdominal wall fasciae variance (PMCTEO/IO, PMCTIO/TrA and PMCTTrA/IA). These variables were from RUSI‐IV (LuM thickness at rest, activation of IO and TrA), body composition (percent fat) and clinical physical examination (lumbar and pelvis flexion ROM, aberrant movements, passive and active straight‐leg raise, loaded‐reach test) from the biological domain, as well as from the lifestyle (physical activity level during sports), psychological (psychological distress—cognitive subscale, fear‐avoidance beliefs during physical ac...

Research Progress of Paraspinal Muscle Fat Infiltration in Osteoporotic Vertebral Compression Fractures

“…Reiter studied the relationship between energy metabolism and body composition of skeletal muscle in healthy adults and believed that muscle fat infiltration not only leads to a decrease in muscle strength and endurance, but also causes muscles to lose elasticity and repairability [16] . A large number of studies have shown that [17][18][19] paraspinal muscle fat infiltration is common in elderly people, especially in elderly patients with spinal degenerative changes. Paraspinal muscle fat infiltration not only leads to damage of paraspinal muscle strength and decreased spinal stability, affecting the normal physiological function of whole body movement, but also increases the failure rate of spine surgery and affects the effect of postoperative rehabilitation and extends the recovery time under severe infiltration of adipose tissue [10,20] .…”