Factors influencing the surgical decision for the treatment of degenerative lumbar stenosis in a preference-based shared decision-making process

In a preference-based shared decision-making system, several subjective and/or objective factors such as pain severity, degree of disability, and the radiological severity of canal stenosis may influence the final surgical decision for the treatment of lumbar spinal stenosis (LSS). However, our understanding of the shared decision-making process and the significance of each factor remain primitive. In the present study, we aimed to investigate which factors influence the surgical decision for the treatment of LSS when using a preference-based, shared decision-making process. We included 555 patients, aged 45-80 years, who used a preference-based shared decision-making process and were treated conservatively or surgically for chronic leg and/or back pain caused by LSS from April 2012 to December 2012. Univariate and multivariable-adjusted logistic regression analyses were used to assess the association of surgical decision making with age, sex, body mass index, symptom duration, radiologic stenotic grade, Oswestry Disability Index (ODI), visual analog scale (VAS) scores for back and leg pain, Short Form-36 (SF-36) subscales, and motor weakness. In univariate analysis, the following variables were associated with a higher odds of a surgical decision for LSS: male sex; the VAS score for leg pain; ODI; morphological stenotic grades B, C, and D; motor weakness; and the physical function, physical role, bodily pain, social function, and emotional role of the SF-36 subscales. Multivariate analysis revealed that male sex, ODI, morphological stenotic grades C and D, and motor weakness were significantly associated with a higher possibility of a surgical decision. Motor weakness, male sex, morphological stenotic grade, and the amount of disability are critical factors leading to a surgical decision for LSS when using a preference-based shared decision-making process.