Paraspinal Muscle Quality and Adjacent Facet Joint Degeneration as Significant Predictors of ASDis Revision After Lumbar Fusion

Background Posterior lumbar interbody fusion (PLIF) combined with pedicle screw internal fixation is widely used for treating lumbar degenerative diseases. However, adjacent segment disease (ASDis) requiring revision surgery is a severe complication, and few studies have focused on this complication. Paraspinal muscle mass loss is associated with lumbar diseases and poor postoperative prognosis, but its relationship with ASDis revision remains unclear Purpose To explore the relationship between paraspinal muscle quality and ASDis revision after lumbar fusion and identify its independent risk factors. Methods Patients who underwent revision surgery for the development of ASD at our hospital were enrolled. To evaluate the risk factors for revision, we selected a control group. Each patient in the control group was matched by age, sex, height, weight, BMI, number of fused segments and follow-up duration with a patient in the revision group. Paraspinal muscle parameters, including the cross-sectional area (CSA), functional cross-sectional area (FCSA), CSA-vertebral index (CSA-VI), FCSA-vertebral index (FCSA-VI), and FCSA/CSA ratio, at the third lumbar (L3) and fourth lumbar (L4) levels were measured via MRI. Receiver operating characteristic (ROC) curves and logistic regression were used for analysis. Results At the L3 and L4 levels, the FCSA, FCSA-VI and FCSA/CSA ratio of the paraspinal, erector spinae and multifidus muscles were significantly lower in the revision group ( P  < 0.05). The L4 paraspinal muscle FCSA/CSA ratio had the highest area under the curve (AUC) (0.942). Preoperative adjacent facet joint degeneration was greater in the revision group ( P  < 0.05). Logistic regression revealed that L4 paraspinal muscle FCSA/CSA ratio (odds ratio = 0.731, P  < 0.001) and preoperative adjacent facet joint degeneration (odds ratio = 4.664, P  = 0.023) were independent risk factors. Conclusion Decreased paraspinal muscle quality is associated with ASDis revision. L4 paraspinal muscle FCSA/CSA and preoperative adjacent facet joint degeneration can predict ASDis revision. Conclusion: A decreased paraspinal muscle mass is associated with ASDis revision. L4 paraspinal muscle FCSA/CSA ratio and preoperative adjacent facet joint degeneration are independent risk factors for ASDis revision.