Complications of posterior lumbar interbody fusion when using a titanium threaded cage device.

OBJECT: The authors reviewed their series of patients to quantify clinical and radiographic complications in those who underwent a posterior lumbar interbody fusion (PLIF) procedure in which a threaded interbody cage (TIC) was implanted.

METHODS: Sixty-seven patients underwent a posterior lumbar interbody fusion procedure in which a TIC was used. The authors excluded patients who underwent procedures in which other instrumentation was used or a nondorsal approach was performed. Fifteen percent of the cases (10 patients) were complicated by laceration of the dura. In three cases, bilateral implantation could not be performed. The average blood loss was 670 ml for all cases, and blood transfusion was required in 25% of the cases (17 patients). The rate of minor wound complication was 4.5% (three patients). One patient died. The average period of hospitalization was 4.25 days. Twenty-eight patients (42%) experienced significant low-back pain 3 months postoperatively, and in 10 (15%) of these cases it persisted beyond 1 year. In 10 patients postoperative radiculopathy was demonstrated, and magnetic resonance imaging revealed epidural fibrosis in six patients, arachnoiditis in one, and a recurrent disc herniation in one. One patient incurred a permanent motor deficit with sexual dysfunction. Pseudarthrosis was suggested radiographically with evidence of motion on lateral flexion-extension radiographs (10 cases), lucencies around the implants (seven cases), and posterior migration of the cage (two cases). Additional procedures (in 14 patients) consisted primarily of transverse process fusion with pedicle screw and plate augmentation for persistent back pain and radiographically demonstrated signs of spinal instability. In two patients with radiculopathy, migration of the TIC required that it be removed. Graft material that extruded from one implant necessitated its removal. In one patient scarectomy was performed.

CONCLUSIONS: Our high incidence of TIC-related complications in PLIF is inconsistent with that reported in previous studies.