Background Data: Surgical treatment of isthmic spondylolisthesis includes decompression, fixation and bone fusion. There are different suitable techniques for fusion as (PLF) posterolateral fusion (TLIF) transforaminal lumbar interbody fusion, (PLIF) posterior lumbar interbody fusion, (ALIF) anterior lumbar interbody fusion but still controversy remains about the best technique.
Purpose: To evaluate and compare the surgical results of PLF versus TLIF with pedicle screw fixation in treatment of low-grade isthmic spondylolisthesis.
Study design: A prospective randomized clinical case series.
Patients and methods: This study included 40 patients with low grade isthmic spondylolisthesis. All patients were surgically treated by posterior decompression, transpedicular screw fixation and bone fusion. Patients were divided into two equal groups according to the type of bone fusion. Group A included 20 patients treated with PLF, and Group B included another 20 patients and were treated with TLIF. We used Visual Analogue Scale (VAS) for assess pain and the Oswestry Disability Index (ODI) to evaluate the functional outcome among our patients. Patients have been followed up for at least six months after surgery.
Results: The improvement of VAS of back pain was significantly greater in group B (TLIF) (change 5.25±1.55) than in group A (PLF) (change, 4.4±1.14) (P<0.05). There was no significant difference in improvement of ODI in both groups. Patients with BMI³30 showed that group B experienced more clinical improvement than in group A in the VAS (P=0.021). The operative time in group B (185±24.5 min) was significantly longer than in group A (123.3±19.6 min) (P=0.034). Intraoperative blood loss in group B (584±192.1 ml) was significantly greater than in group A (417±182.4 ml) (P=0.008). The complication rate in group A (30%) was significantly less than in group B (55%) (P= 0.032) but broken screws (hardware failure) were more common in group A (20%) than in group B (0.0%) (P=0.01). The fusion rate in group B (95%) was higher than in group A (75%).
Conclusion: Our data suggest that although TLIF is better than PLF in achievement of successful bone fusion and improvement of patient's symptoms (back pain and sciatica), PLF still considered simple technique with minimal operative blood loss, less operative time and little complications. (2018ESJ162)