Purpose <p>The objective of the study is to analyze the presence of <i>Cutibacterium Acnes</i> in the skin, subcutaneous tissue and deep tissue when performing primary lumbar spine surgery for degenerative pathology.</p> Methods <p>prospective study including consecutive patients, over 18 years of age, who underwent surgery for degenerative lumbar spine pathology through a posterior approach for the first time. 8 samples were obtained, 6 at the beginning of the intervention (2 skin, 2 subcutaneous, 2 deep tissue) and 2 at the end (1 deep tissue, 1 subcutaneous) for each patient following the Oxford protocol. Age, sex, and presence of previous facet/epidural infiltrations were recorded.</p> Results <p>560 tissue samples were obtained from the 70 patients included. 52.8% were men, with an average of 56.2 years (SD 16.71). 57 samples were positive corresponding to 19 patients (27%). Men (<i>p</i> &lt; 0.008) and patients under 50 years of age (<i>p</i> &lt; 0.018) had more positive cultures. 71% of patients with positive deep tissue at the end of the intervention initially had positive samples in skin or subcutaneous tissue. According to the multivariate logistic regression analysis carried out adjusted for age and sex, having a positive skin and/or subcutaneous tissue sample obtained at the beginning of the intervention implies a 20 times greater risk of having a positive deep tissue culture at the end of the procedure (p 0,00).</p> Conclusion <p>The results of this study show a colonization rate of <i>Cutibacterium Acnes</i> of 27%,with a higher incidence found in young males.</p>