Primary acquired spondylodiscitis shows a more severe course than spondylodiscitis following spine surgery: a single-center retrospective study of 159 cases

Abstract

Spondylodiscitis may arise primarily via hematogenous spread or direct inoculation of virulent organisms during spine surgery. To date, no comparative data investigating the differences between primary and postoperative spondylodiscitis is available. Thus, the purpose of this retrospective study was to investigate differences between these two etiologies. One hundred fifty-nine patients that were treated at our department were included in the retrospective analysis. The patients were categorized into two groups based on the etiology of spondylodiscitis: group NS, primary spondylodiscitis without prior spinal surgery; group S, spondylodiscitis following spinal surgery. Evaluation included magnetic resonance imaging (MRI), laboratory values, clinical outcome, and operative or conservative management. Preoperative MRI showed higher rates of epidural and paraspinal abscess in patients with primary spondylodiscitis (p < 0.005). Vertebral bone destruction was more severe in group NS (p < 0.05). Survival rate in group S (98.2%) was higher than in group NS (87.5%, p = 0.024). The extent of the operative procedure in patients who were surgically treated (n = 116) differed between the two groups (p < 0.005). In conclusion, spondylodiscitis is a life-threatening and serious disease and requires long-term treatment. Primary spondylodiscitis is frequently associated with epidural and paraspinal abscess, vertebral bone destruction and has a higher mortality rate than postoperative spondylodiscitis. Therefore, primary spondylodiscitis shows a more severe course than spondylodiscitis following spine surgery.

Keywords: Discitis; Epidural abscess; Postoperative spondylodiscitis; Primary spondylodiscitis; Spinal infection.

Fig. 1

Flow chart on the treatment in all patients with primary (NS) and secondary acquired spondylodiscitis (S). n number of patients, c conservatively treated, s surgically treated

Fig. 2

Preoperative magnetic resonance imaging finding in all patients. S secondary acquired spondylodiscitis, NS primary acquired spondylodiscitis, p significance

Fig. 3

Overall pain on numeric rating scale (NRS) in a surgically (sS, sNS) and b conservatively treated patients (cS, cNS). S secondary acquired spondylodiscitis, NS primary acquired spondylodiscitis, c conservatively treated, s surgically treated. ★★ƒ: differences in follow-up: p < 0.005, ★★: differences between groups: p < 0.005. a FD first diagnosis, A day of admission, 3d third postoperative day, D discharge, 3m and 12m 6m and 12 months follow-up. b FD first diagnosis, d days after the first diagnosis, m months after the first diagnosis

Fig. 4

Inflammatory blood value in a surgically (sS, sNS) and b conservatively treated patients (cS, cNS). CRP C-reactive protein, S secondary acquired spondylodiscitis, NS primary acquired spondylodiscitis, c conservatively treated, s surgically treated. ★★ƒ: differences in follow-up: p < 0.005, ★ƒ: differences in follow-up: p < 0.05, ★: differences between groups: p < 0.05. a FD first diagnosis, A day of admission, 3d third postoperative day, D discharge, 3m and 12m 6 and 12 months follow-up. b FD first diagnosis, d days after the first diagnosis, m months after the first diagnosis