INTRODUCTION: 

Most cases of pyogenic spondylitis can be treated non-surgically, but some cases require surgical intervention. Although there are some reports minimally-invasive posterior fixation is effective for refractory cases, in patients with lumbar spine disease, treatment could be difficult due to inadequate fixation of the caudal side. In this study, we report five cases of lumbo-iliac fixation with sacral alar iliac (SAI) screws as the distal anchors for middle or lower lumbar pyogenic spondylitis refractory to conservative treatment.

PATIENTS AND METHODS

We reviewed medical charts of consecutive five cases of lumbar spondylitis treated surgically using SAI screws. We collected data involving sex, age, follow-up period, time to surgery from initial diagnosis, complicated disease associated with pyogenic spondylitis, the level of infection site, surgical procedures, postoperative complications, and the presence of postoperative infection recurrence.

RESULTS:

All cases treated surgically are male. The average age was 62.2 (range, 49–72) years old. The average follow-up period was 12.4 (range, 10–21) months. Time to surgery from initial diagnosis was averaged 100.6 (range, 58–175) days. All cases have underlying illness, mainly diabetes mellitus in three patients, liver cirrhosis in two patients, and rheumatoid arthritis in one patient. The level of infection site were L3/4 in two patients, L4/5 in one patient, and L5/S in two patients. Among five cases, one patient underwent L3-S1 posterior fixation with percutaneous pedicle screws previously. However, 6 months after surgery, S1 screws were loosened and the infection could not be healed. All cases were treated surgically with posterior fixation using SAI screws. Th12-iliac fixation in two patients, L1-iliac fixation in one patient, and L3-iliac fixation in two patients were performed, respectively. Time required for C-reactive protein levels to return to normal was averaged 95.6 (range, 27–300) days. No additional surgical interventions such as anterior debridement nor postoperative complications developed at final follow-up.

RESULT AND DISCUSSION:

In our series, minimally invasive lumbar-pelvic posterior fixation using SAI screws were very effective for the treatment of pyogenic spondylitis refractory to conservative treatment. All patients who underwent surgery were free to move and signs of infection improved dramatically after surgery. Spinal fixation using SAI screws could be beneficial for refractory pyogenic spondylitis of the middle or lower lumbar spine.