[Effectiveness of posterior pedicle screw system combined with interbody fusion in treating lumbar spondylolisthesis].

OBJECTIVE

To analyze the effectiveness of posterior pedicle screw system combined with interbody fusion in treating lumbar spondylolisthesis.

METHODS

Between January 2005 and January 2009, 26 patients with lumbar spondylolisthesis underwent posterior pedicle screw system combined with interbody fusion, including 11 males and 15 females with an average age of 56.8 years (range, 36-73 years). The disease duration was 7 months to 11 years. The affected lumbars were L3 in 3 cases, L4 in 12 cases, and L5 in 11 cases. According to the Meyerding evaluating system, 21 cases were classified as degree III, 5 cases as degree III-IV, and 1 case as degree IV. The clinical results were investigated by measuring radiographic measurements, including Taillard index, Boxall index, slipping angle, lumbar lordosis angle, and intervertebral height index preoperatively, immediately, 2 weeks and 3 months postoperatively, respectively. SUK's criteria was used to judge bone graft fusion.

RESULTS

Primary healing of the incisions was achieved in all cases. All patients were followed up 25.8 months on average (range, 10-51 months). There were significant differences in Taillard index, Boxall index, slipping angle, lumbar lordosis angle, and intervertebral height index between preoperatively and immediately, 2 weeks, 3 months after operation (P < 0.05). Bone graft fusion was achieved at 3-8 months after operation (mean, 3.5 months); and the fusion rate was 100%. According to Japanese Orthopedic Association (JOA) scoring, the results were excellent in 17 cases, good in 7 cases, fair in 1 case, and poor in 1 case; and the excellent and good rate was 92.3%. Complications occurred in 2 cases, including nail or rod breakage and nerve injury, and they were cured after treatment.

CONCLUSION

Posterior pedicle screw system combined with interbody fusion treating lumbar vertebral spondylolisthesis can afford solid internal fixation and achieve a satisfactory reduction, so it maybe an ideal procedure and a worthy recommended method for treating lumbar spondylolisthesis.