Spondylodiscitis after lumbar microdiscectomy

The incidence of spondylodiscitis after lumbar microdiscectomy ranges from 0.2% to 15%. There is limited evidence to compare different techniques and the incidence of spondylodiscitis.

A total of 3063 patients were analyzed from 2005 to 2011 for discitis postoperatively. The first group followed a standard microdiscectomy technique, the second group used antiseptic chlorhexidine (Savlon; Novartis Consumer Health UK Limited, Surrey, UK) irrigation at the end of the procedure to irrigate the disc space, and the third group followed standard microdiscectomy along with usage of a separate disc instruments when discectomy was performed. The number of patients operated in the individual groups was 559, 1122, and 1382.

The total number of patients who had postoperative discitis was 3 (0.10%), with a range of 0.07% to 0.18%. There was 1 case of discitis in each group. The incidence of spondylodiscitis in groups A, B, and C were 0.18%, 0.09%, and 0.07%, respectively.

This study concluded that different techniques used for lumbar microdiscectomy revealed that standard microsurgical technique with usage of antiseptic irrigation for the disc space and usage of separate disc instruments had lesser incidence of spondylodiscitis in comparison with standard microdiscectomy. The overall incidence of postoperative discitis remains less in our series. So far, to our knowledge, this report involves the largest number of patients studied to determine the incidence of discitis in patients undergoing lumbar microdiscectomy ¹⁾.

The role of antibiotic prophylaxis in preventing postoperative lumbar spondylodiscitis is still controversial in medical, ethical, economic, and legal terms. The aim of the retrospective study by Mastronardi et al., was to evaluate the efficacy of two intraoperative antibiotic prophylaxis protocols in a large series of lumbar microdiscectomies performed in two different neurosurgical centres. They reviewed the outcome of 1167 patients operated on for a lumbar disc herniation with microsurgical technique, in order to detect the incidence of postoperative spondylodiscitis.

Group A included 450 patients operated on in a 3-year period in the Neurosurgical Division of the University Hospital of Ancona; group P consisted of 717 patients operated on in a 4-year period in the Neurosurgical Division of the Sandro Pertini Hospital of Rome. In both groups intraoperative antibiotics for prophylaxis were administered, whereas postoperative prophylaxis was not performed. Protocol of group A: single intravenous dose of cefazoline 1 g at induction of general anesthesia and generous washing with saline solution and irrigation with a solution containing rifamicin at the end of microsurgical procedure. Protocol of group P: single-dose of intravenous ampicillin 1000 mg and sulbactam 500 mg at induction of anesthesia and generous irrigation with saline solution at the end of microsurgical procedure. A diagnosis of postoperative spondylodiscitis was made in three out of 450 patients in group A (0.67%) and in 5 out of 717 patients in group P (0.69%). In all cases, treatment consisted of rigid thoraco-lumbar orthesis and 4- to 6-week administration of amoxicillin/clavulanate compound (500/125 mg). The low incidence of postoperative spondylodiscitis obtained with both our protocols seems to confirm that intraoperative antibiotic prophylaxis is associated with the same rate of discitis of prolonged prophylaxis usually still adopted in many centres, but is more advantageous both in terms of welfare and comfort for patients and in economic terms. However, at the moment it is not possible identify the ideal antibiotic for this purpose. It seems to be reasonable to search for the solution through large multicenter prospective studies ²⁾.

An analysis of the incidence of spondylodiscitis after lumbar disc surgery in 1642 patients. In 508 patients no prophylactic antibiotics were given. In 1134 patients a Gentamicin-collagen sponge was placed in the cleared disc space.

To report the incidence of postoperative spondylodiscitis in cases in which no antibiotic prophylaxis was used, and to define the value of a collagenous sponge containing gentamicin in preventing disc space infections.

Spondylodiscitis is considered to be a rare complication of lumbar disc surgery. The retrospective design of most studies and the rare use of magnetic resonance imaging for early radiologic diagnosis suggest that the reported incidence rates may be underestimates. Postoperative spondylodiscitis is the result of intraoperative contamination and, theoretically, could be prevented by treating these patients with prophylactic antibiotics.

In 1642 patients, 1712 discectomies were performed. In 508 of these patients no prophylactic antibiotics were given; in 1134 of these patients a collagenous sponge containing gentamicin was placed in the cleared disc space. Clinical reexamination and, in cases of unsatisfactory results, laboratory and radiologic investigations were performed 4-8 weeks after surgery.

In nineteen of the 508 patients who were not treated with antibiotic prophylaxis (3.7%) a postoperative spondylodiscitis developed, whereas none of the 1134 patients who received antibiotic prophylaxis became symptomatic (P < 0.00001).

In the current study, a 3.7% incidence of postoperative spondylodiscitis was found in the absence of prophylactic antibiotics. Gentamicin-containing collagenous sponges placed in the cleared disc space were effective in preventing postoperative spondylodiscitis ³⁾.

73-year-old male operated on L5-S1 lumbar disc herniation 2 month before. C-REACTIVE PROTEIN 2.15mg/dL, Erythrocyte sedimentation rate 35 mm

Signal alteration in L5 and S1 vertebral body with hypointense behavior on T1 weighted image sequence

Hyperintense on STIR attributable to edema, with enhancement of the vertebral bodies as well as perivertebral soft tissues. The intervertebral disc L5-S1 presents an increase in its signal in STIR in its middle and posterior third that continues with an abscess in the left paracentral operated extruded disc area that presents peripheral enhancement and that obliterates the left recess and displaces the thecal sac , with approximate measurements of 23 mm x 22 mm (axial x cc), contacting the ipsilateral S1 root. Peri and paravertebral inflammatory changes in the left anterior and posterior epidural space, as well as in the surgical path of the left laminectomy. The findings are compatible with spondylodiscitis L5-S1 with a disc abscess in its middle-posterior third that presents an extrusion to the left recess. Signs of degeneration and dehydration of the L3-L4 discs with loss of disc space height, marginal osteophytes and Modic type II changes in the adjacent plates, without significant canal stenosis.