FACTORS, AFFECTING FUNCTIONAL OUTCOMES IN PATIENTS WITH LOW-GRADE ISTHMIC SPONDYLOLISTHESIS AFTER SURGICAL TREATMENT
INTRODUCTION. Transforaminal lumbar interbody fusion with posterior instrumentation is widely used to treat patients with low-grade isthmic spondylolisthesis. Current evidence regarding factors that may affect functional outcomes is still controversial. OBJECTIVE. To identify the factors that may affect the severity of functional adaptation disorders in patients with low-grade isthmic spondylolisthesis after surgery. METHODS. Fourty-eight patients older than 18 years with isthmic spondylolisthesis who underwent transforaminal lumbar interbody fusion and posterior screw-rod instrumentation from 2018 to 2020, were retrospectively analyzed. The effect of gender, age, obesity, smoking, paravertebral muscle condition, the interbody height, degree of vertebral translation prior to surgery, amount of vertebral reduction performed, initial level of functional condition, approach to performing of interbody fusion and instrumentation on functional outcome measured by Oswestry scale was analyzed. RESULTS. The degree of functional desadaptation after surgical treatment can be reliably affected by the patient’s excess body weight (BMI > 30) (p = 0.044). During the correlation analysis, a statistically significant association was observed between the degree of functional desadaptation of patients after surgery with initial functional status (rho = 0.418, p = 0.003) and the relative size of the psoas muscle (rho = -0.327, p = 0.023). CONCLUSION. This study showed that adverse functional outcomes in patients with low-grade isthmic spondylolisthesis may be associated with obesity, functional status prior to surgery, the relative size of the psoas muscle. For this reason, it is necessary inform patients that some of the factors are modifiable, which means lifestyle correction, obesity treatment can significantly reduce the degree of functional desadaptation after surgery.