Comparative Study of Posterior Lumbar Interbody Fusion with Posterolateral Fusion in Degenerative Lumbar Spinal Disorders

STUDY DESIGN: A retrospective study. OBJECTIVES: The authors found that problems such as axial pain, donor site pain, loss of reduction, loosening or failure of fixation materials occurred relatively frequently after posterolateral fusion. For this, we had views on the ideas that the problems could be improved by an operation that fused vertebral bodies. Furthermore, we performed posterior lumbar interbody fusion and wanted to know the results. SUMMARY OF LITERATURE REVIEW: We performed posterior lumbar inter-body fusion as an alternative, due to complications of autoiliac bone graft that has complications, such as donor site pain. MATERIALS AND METHODS: Sixty patients with single segment degenerative lumbar disease were treated with decompression, pedicle screws fixation, and spinal fusion. The patients were followed-up for more than 2 years. Thirty patients, who had undergone posterolateral fusion with autologous iliac bone graft, were classified as the "group 1". The second 30 patients, who underwent posterior lumbar interbody fusion with cage and local bone graft, were classified as the "group 2". The operation time, blood loss, fusion rate, lumbar lordotic angle, segmental angle were compared between the 2 groups. The clinical outcomes were evaluated by Kim's functional evaluation scale. RESULTS: The operation time was shorter in group 2 (142.74 minutes vs 171.64 minutes), there was a statistical difference between the 2 groups. Intraoperative blood loss was more in group 2 (563.40 vs 551.78 mL), but total blood loss, including postoperative drained blood was less in group 2. The bony fusion rate was 90% in group 1, 97% in group 2. For the lumbar lordotic angle, the last outcome was less than the preoperative value. There was no statistical difference between the 2 groups. The segmental angle in group 1, the last outcome was less than the preoperative value. The segmental angle in group 2 was maintained the value through pre-operation to post-operation. Clinical outcomes were satisfactory in group 1 (96.67%) & in group 2 (100%). In group 1, 7 patients experienced pain at the iliac graft donor site. In group 2, there were 2 cases of retroposition of the cage. CONCLUSIONS: In the posterior lumbar interbody fusion group, operation time was shorter, total blood loss was less than in the posterolateral fusion group. Restoration and maintenance of the segmental angle in sagittal and coronal radiographs showed better outcomes, axial pain and iliac donor site pain were less. It is the authors' position that posterior lumbar interbody fusion is an alternative operation to supplement the faults of posterolateral fusion.

Clinical Efficacy of a Stand-Alone, Threaded-Titanium Fusion Cage for Single-Level Degenerative Lumbar Spinal Disorders / 대한정형외과학회잡지

PURPOSE: To evaluate the clinical and radiologic efficacy of posterior lumbar interbody fusion (PLIF) using a threaded fusion cage (TFC) alone with autogenous iliac corticocancellous bone graft for single-level degenerative lumbar spinal disorders. MATERIALS AND METHODS: Thirty-eight consecutive patients receiving PLIF with TFC alone were evaluated with at least three years of follow-up. Clinical outcome and satisfaction were assessed using Ragab's measurements. Radiological outcomes were analyzed in terms of lumbar lordosis, segmental lordosis, disc height, and fusion rates. RESULTS: Disc height was 6.18+/-2.54 mm, 11.71+/-1.60 mm and 9.94+/-1.94 mm on average for preoperative, postoperative, and final follow-up, respectively. Lumbar lordosis was 27.46+/-11.47degrees, 31.41+/-8.89degrees on average for preoperative and at final follow-up, respectively. Segmental lordosis was 11.51+/-9.35degrees preoperatively, and 10.86+/-7.49degrees at final follow-up. Satisfactory clinical outcome were obtained in 89.2% of patients with successful bone fusion in 73.0% of patients. CONCLUSION: Stand alone TFC is an effective treatment modality in maintenance of disc height and lumbar lordosis, with satisfactory long term clinical outcomes in the treatment of single-level degenerative lumbar spinal disorders.

Comparison of Posterior Lumbar Interbody Fusion with Posterolateral Fusionin Degenerative Lumbar Spinal Disorders / 대한정형외과학회잡지

PURPOSE: This study compared the surgical treatment results between posterior lumbar interbody fusion (PLIF) and posterolateral fusion (PLF) with pedicle screw fixation in degenerative lumbar spinal disorders. MATERIALS AND METHODS: In 45 cases of PLF (group I) and 45 cases of PLIF (group II), lumbar lordosis, segmental lordosis, bone union and complications were considered to be an evaluation criterion. Kim's functional evaluation scale was used for the clinical results. RESULTS: The average lumbar lordosis in group I was 36.84+/-8.31 degrees preoperatively, 40.58+/-7.61 degrees postoperatively and 35.73+/-7.61 degrees at the last follow up. On the other hand, the respective changes in the average lumbar lordosis were 31.53+/-7.09 degrees, 39.11+/-7.21 degrees, and 35.47+/-7.76 degrees in group II. Definitive solid union was obtained in 41 cases in group I (91.1%) and 43 cases in group II (95.6%). The rate of complications was 24.4% (11 cases) in group I and 2.2% (6 cases) in group II, and a satisfactory functional outcome were obtained in 43 cases (95.6%) in group I and 41 cases (91.1%) in group II. CONCLUSION: Both PLF and PLIF on short segment fusion provided satisfactory bone union and clinical results. In segmental lordosis, there were no significant differences between the two groups. However, PLIF was more effective in preventing lumbar lordosis and complications than PLF. A longer term follow up will be needed to evaluate the adjacent segmental degeneration and maintenance of the sagittal balance.

The Results of Long Segment Posterolateral Fusion in Degenerative Lumbar Spinal Disorders / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to evaluate the safety and the validity of the long level posterolateral fusion with pedicle screw augmentation in the surgical treatment of degenerative lumbar spinal disorders in older patients. MATERIALS AND METHODS: A radiological evaluation such as fusion rate, the changes of lordotic angle, metal failure and junctional problem, and clinical results about a 33 patients older than 50 years of age in whom a posterolateral fusion has been performed on more than three segments were analyzed. RESULTS: Arthrodesis was obtained in 23 cases and the changes in the lordotic angle was 7.9+/-5.2degrees. Satisfactory results were obtained in 20 cases, fair in 8 and poor in 5 cases. Satisfactory results were obtained in 12 of the 16 cases in which S1 was included in the arthrodesis and 8 of the 17 cases in which S1 was not included in the arthrodesis. The post-surgical complications encountered were as follows: Wound infection in 5 cases, metal loosening or failure in 12, bone graft donor site problem in 2 and junctional problems in 8 cases. Revision surgery was performed in 9 cases. CONCLUSION: Long segment fusion in degenerative lumbar spinal disorders should be considered carefully in old age because of the high rate of post-surgical complications and unsatisfactory clinical outcomes.

The Changes of Adjacent Segments after Fusions (above 3-levels to L5) in Degenerative Lumbar Spinal Disorders / 대한척추외과학회지

STUDY DESIGN: A retrospective study. OBJECTIVE: To evaluate the usefulness of MRI grading of disc degeneration in determining whether L5-S1 fusion is necessary in degenerative lumbar spinal disorders. SUMMARY OF LITERATURE REVIEW: Changes in adjacent segments are not well understood, after floating fusion has been performed. MATERIALS AND METHODS: We reviewed 16 surgical cases of degenerative lumbar spinal disorders from July 1996 to February 2000 with an average follow-up of 41 months. Fusion was done in patients without instability, pathology and narrowing of L5-S1. We measured the disc degeneration of adjacent segments in preoperative MRIs using the Modified Pearce classification. In spine AP, lateral and flexion-extension radiographs, we measured disc height, angular motion and instability changes and correlated these with disc degeneration. RESULTS: Disc height changes decreased in the upper and lower adjacent segments and preoperative disc degeneration above grade IV, decreased more in lower adjacent segment. A statistical correlation was found between disc degeneration and disc height changes in the lower segment (P=0.046), but not in the upper segment (P=0.649). The angular-motion was unchanged in the upper and lower adjacent segments, and no statistical correlation was found between disc degeneration and angular-motion changes (P=0.819, 0.208). Postoperative instability was found in the upper adjacent segment in 2 patients, but no statistical cor-relation was found between disc degeneration and instability (P=0.083, P=1.000). CONCLUSION: L5-S1 might be saved when free of pathology, and when disc degeneration is below grade III and balanced sagit-tally. However, further study is needed because of the short-term follow up and low number of cases in this study.