Decreased muscle mass and strength affected spinal sagittal malalignment

Area of Science:

• Geriatric Medicine
• Orthopedics
• Biomedical Engineering

Background:

• Spinal malalignment correction surgery has risks.
• Early intervention is crucial for spinal sagittal alignment.
• Understanding factors influencing spinal alignment is needed.

Purpose of the Study:

• To investigate the impact of muscle mass and strength on spinal sagittal imbalance.
• To determine the natural course and influencing factors of spinal alignment.

Main Methods:

• A multicenter cross-sectional study included 1823 patients (mean age 69.2 years).
• Data collected included age, sex, BMI, grip strength (GS), and trunk muscle mass (TM).
• Spinal sagittal imbalance was classified using SRS-Schwab; statistical analyses included multiple comparisons and logistic regression.

Main Results:

• Advancing age, lower trunk muscle mass (TM) in women, and lower grip strength (GS) in both sexes correlated with spinal malalignment.
• Age and BMI were positively associated with malalignment.
• Low TM and GS were negatively associated with spinal sagittal malalignment.

Conclusions:

• Aging, obesity, low TM, and low GS are potential risk factors for spinal sagittal malalignment.
• Low muscle mass and strength are linked to more severe spinal malalignment.
• Early muscle-focused interventions are recommended for individuals with normal or mild spinal alignment.