MATERIAL and METHODS: The study included 57 patients (19 males, 38 females) who were diagnosed with SI and 44 healthy control subjects. Spinal sagittal balance was evaluated using digitalized-standing lumbar lateral radiographs of the patients. All parameters including SS, PI, LL and PT were evaluated through from the lateral radiographs.

RESULTS: In the analysis, Mean Platelet Volume (MPV) (10.6 ± 0.9; p<0.0001), Platelet Distribution Width (PDW) (12.7 ± 2.2; p<0.001) and Platelet Distribution Width (RDW) (41.9 ± 4.4; p<0.0001) were observed to be much higher in the SI than in the control. The neutrophil-lymphocyte ratio (NLR) was higher in the SI group (p=0.033), and no difference was determined in respect of the platelet-lymphocyte ratio (PLR) (p>0.05). The PT had a positive correlation with hospital length of stay in SI patients (r=0.655; p=0.008). MPV showed a strong positive correlation with comorbidity (r=0.715; p=0.001). A positive correlation was determined between NLR and PLR (r=0.692; p=0.002), and between MPV and RDW (r=0.788; p=0.001). No correlation was determined between the PAIP and radiological measurements (PI, PT, SS) that were used for SI.

CONCLUSION: The results suggest that the neurosurgical approach should cover not only the sagittal parameters and their angles but also PAIP showing inflammatory events originating from platelets. Keywords : Spine, Sagittal imbalance, Platelet, Inflammation