Comparing perioperative and postoperative outcomes and complications of ALIF and LLIF

Purpose: This paper compares anterior lumbar intercorporeal fusion (ALIF) and lateral lumbar intercorporeal fusion (LLIF). LLIF is an approach through the lateral retroperitoneal corridor, transpsoas. ALIF is a described alternative to interbody fusion with approach variations described as retroperitoneal, transperitoneal, open, and laparoscopic. Our objective is to compare complications can occur in both approaches the ALIF and the LLIF, to see what the advantages and disadvantages are during the perioperative and postoperative. Method: This is a literature review article. A MEDLINE search was conducted through PubMed, google scholar, science direct, and Cochrane to identify articles that reported the differences between ALIF, LLIF and other lumbar interbody fusion approaches focusing the complications, cost and length of surgery, length of hospitalization, narcotic use, sagittal balance and surgical technique. Result: There was no overall significant difference in the postoperative narcotic use, fusion rate, and disc height. However, ALIF was seen to have better postoperative sagittal balance. Although long-term complication rates between ALIF and LLIF are not statistically even though the procedures have procedure-specific complications. Intraoperative blood loss and operative time were relatively higher in ALIF than in LLIF. The risk of injury to the lumbar plexus and iliac vessels is relatively higher than ALIF. Conclusion: ALIF and LLIF they are considered safe, effective and non-invasive. Both procedures present their pearls and pitfalls, but LLIF is associated with more complications than ALIF, although they do not present great differences of clinical outcomes. There is a need more extensive research to determine the best approach.

Propósito: Este trabajo compara la fusión intercorpórea lumbar anterior (ALIF, por sus siglas en inglés) y la fusión intercorpórea lumbar lateral (LLIF, por sus siglas en inglés). LLIF es una aproximación a través del corredor retroperitoneal lateral, con transpsoas. La ALIF es una alternativa a la fusión intercorporal con variaciones de abordaje descritas como retroperitoneal, transperitoneal, abierta y laparoscópica. Nuestro objetivo es comparar las complicaciones que pueden ocurrir en ambos abordajes de la ALIF y la LLIF, para ver cuáles son las ventajas y desventajas durante los procesos perioperatorio y postoperatorio. Método: Este es un artículo de revisión de literatura. Se realizó una búsqueda MEDLINE a través de PubMed, Google Scholar, Science Direct y Cochrane para identificar artículos que reportaron las diferencias entre ALIF, LLIF y otros enfoques de fusión intercorporal lumbar enfocándose en las complicaciones, el costo y la duración de la cirugía, duración de la hospitalización, uso de estupefacientes, equilibrio sagital y técnica quirúrgica. Resultado: No hubo diferencia significativa general en el uso posoperatorio de narcóticos, la tasa de fusión y la altura del disco. Sin embargo, se observó que la ALIF tenía un mejor equilibrio sagital postoperatorio. Aunque las tasas de complicaciones a largo plazo entre ALIF y LLIF no son estadísticamente significativas a pesar de que los procedimientos tienen complicaciones específicas del procedimiento. La pérdida de sangre intraoperatoria y el tiempo operativo fueron relativamente más altos en ALIF que en LLIF. El riesgo de lesión en el plexo lumbar y los vasos ilíacos es relativamente mayor que la ALIF. Conclusiones: ALIF y LLIF se consideran métodos seguros, eficaces y no invasivos. Ambos procedimientos presentan aciertos y desaciertos, pero el LLIF se asocia a más complicaciones que el ALIF, aunque no presentan grandes diferencias en los resultados clínicos. Se necesita una investigación más amplia para determinar el mejor enfoque.

Biomechanical Properties of Porous Titanium Cages for Different Lumbar Interbody Fusion Surgeries / 医用生物力学

Objective To study the biomechanical properties of porous titanium cages used for different lumbar interbody fusion surgeries. Methods The three-dimensional (3D) finite element model of the lumbar spine was constructed, and mechanical parameters of porous materials were obtained by mechanical test. The biomechanical properties of porous titanium cages in anterior lumbar interbody fusion (ALIF), posterior lumbar interbody fusion (PLIF), transforaminal lumbar interbody fusion (TLIF), direct lateral interbody fusion (DLIF) were compared. Results After lumbar interbody surgery, the predicted range of motion (ROM) and the maximum stress in cage of DLIF model and ALIF model were substantially lower than those of PLIF model and TLIF model. The maximum stress in endplate of DLIF model, ALIF model and TLIF model were obviously lower than that of PLIF model. Conclusions DLIF with the porous cage showed advantages in biomechanical properties, which was simple to operate and suitable for minimally invasive surgery in clinical practice. DLIF performed the superior comprehensive properties.

Mini-Open Anterior Lumbar Interbody Fusion Combined with Lateral Lumbar Interbody Fusion in Corrective Surgery for Adult Spinal Deformity

STUDY DESIGN: Prospective observational study. PURPOSE: To introduce the techniques and present the surgical outcomes of mini-open anterior lumbar interbody fusion (ALIF) at the most caudal segments of the spine combined with lateral lumbar interbody fusion (LLIF) for the correction of adult spinal deformity OVERVIEW OF LITERATURE: Although LLIF is increasingly used to correct adult spinal deformity, the correction of sagittal plane deformity with LLIF alone is reportedly suboptimal. METHODS: Thirty-two consecutive patients with adult spinal deformity underwent LLIF combined with mini-open ALIF at the L5–S1 or L4–S1 levels followed by 2-stage posterior fixation. ALIF was performed for a mean 1.3 levels and LLIF for a mean 2.7 levels. Then, percutaneous fixation was performed in 11 patients (percutaneous group), open correction with facetectomy with or without laminectomy in 16 (open group), and additional pedicle subtraction osteotomy (PSO) in 5 (PSO group). Spinopelvic parameters were compared preoperatively and postoperatively. Hospitalization data and clinical outcomes were recorded. RESULTS: No major medical complications developed, and clinical outcomes improved postoperatively in all groups. The mean postoperative segmental lordosis was greater after ALIF (17.5°±5.5°) than after LLIF (8.1°±5.3°, p <0.001). Four patients (12.5%) had lumbar lordosis with a pelvic incidence of ±9° preoperatively, whereas this outcome was achieved postoperatively in 30 patients (93.8%). The total increase in lumbar lordosis was 14.7° in the percutaneous group, 35.3° in the open group, and 57.0° in the PSO group. The ranges of potential lumbar lordosis increase were estimated as 4°–25°, 23°–42°, and 45°–65°, respectively. CONCLUSIONS: Mini-open ALIF combined with LLIF followed by posterior fixation may be a feasible technique for achieving optimal sagittal balance and reducing the necessity of more extensive surgery.

Surgical Outcomes of Post-Fusion Lumbar Flatback Deformity with Sagittal Imbalance

OBJECTIVES: To review surgical results of post-fusion lumbar flatback treated with pedicle subtraction osteotomy (PSO) or Smith-Petersen osteotomies (SPOs). METHODS: Twenty-eight patients underwent osteotomies. Radiological outcomes by sagittal vertical axis (SVA), and pelvic tilt (PT), T1 pelvic angle (T1PA), and pelvic incidence (PI)-lumbar lordosis (LL) at preoperative, postoperative 1 month, and final were evaluated. Oswestry Disability Index (ODI), visual analog scale (VAS) score of back pain/leg pain, and Scoliosis Research Society-22 score (SRS-22r) were analyzed and compared. Patients were divided into 2 groups (SVA ≤5 cm : normal, SVA >5 cm : positive) at final and compared outcomes. RESULTS: Nineteen patients (68%) had PSO and the other 9 patients had SPOs with anterior lumbar interbody fusions (ALIFs) (Mean age : 65 years, follow-up : 31 months). The PT, PI-LL, SVA, T1PA were significantly improved at 1 month and at final (p0.05). Common reoperations were early 4 proximal junctional failures (14%) and late four rod fractures. CONCLUSION: Our results demonstrate that PSO and SPOs with ALIFs at the lower lumbar are significantly improves sagittal balance. For maintenance of normal SVA, PI-LL might be made negative value and T1PA might be less than 11° even though positive SVA group was also significantly improved clinical outcomes.

Anterior Lumbar Interbody Fusion for the Treatment of Postoperative Spondylodiscitis

OBJECTIVE: To analyze the clinical courses and outcomes after anterior lumbar interbody fusion (ALIF) for the treatment of postoperative spondylodiscitis. METHODS: A total of 13 consecutive patients with postoperative spondylodiscitis treated with ALIF at our institute from January, 1994 to August, 2013 were included (92.3% male, mean age 54.5 years old). The outcome data including inflammatory markers (leukocyte count, C-reactive protein, erythrocyte sedimentation rate), the Oswestry Disability Index (ODI), the modified Visual Analogue Scale (VAS), and bony fusion rate using spine X-ray were obtained before and 6 months after ALIF. RESULTS: All of the cases were effectively treated with combination of systemic antibiotics and ALIF with normalization of the inflammatory markers. The mean VAS for back and leg pain before ALIF was 6.8+/-1.1, which improved to 3.2+/-2.2 at 6 months after ALIF. The mean ODI score before ALIF was 70.0+/-14.8, which improved to 34.2+/-27.0 at 6 months after ALIF. Successful bony fusion rate was 84.6% (11/13) and the remaining two patients were also asymptomatic. CONCLUSION: Our results suggest that ALIF is an effective treatment option for postoperative spondylodiscitis.

Radiographic Results of Minimally Invasive (MIS) Lumbar Interbody Fusion (LIF) Compared with Conventional Lumbar Interbody Fusion

OBJECTIVE: To evaluate the radiographic results of minimally invasive (MIS) anterior lumbar interbody fusion (ALIF) and transforaminal lumbar interbody fusion (TLIF). METHODS: Twelve and nineteen patients who underwent MIS-ALIF, MIS-TLIF, respectively, from 2006 to 2008 were analyzed with a minimum 24-months' follow-up. Additionally, 18 patients treated with single level open TLIF surgery in 2007 were evaluated as a comparative group. X-rays and CT images were evaluated preoperatively, postoperatively, and at the final follow-up. Fusion and subsidence rates were determined, and radiographic parameters, including lumbar lordosis angle (LLA), fused segment angle (FSA), sacral slope angle (SSA), disc height (DH), and foraminal height (FH), were analyzed. These parameters were also compared between the open and MIS-TLIF groups. RESULTS: In the MIS interbody fusion group, statistically significant increases were observed in LLA, FSA, and DH and FH between preoperative and final values. The changes in LLA, FSA, and DH were significantly increased in the MIS-ALIF group compared with the MIS-TLIF group, but SSA and FH were not significantly different. No significant differences were seen between open and MIS-TLIF except for DH. The interbody subsidence and fusion rates of the MIS groups were 12.0+/-4% and 96%, respectively. CONCLUSION: Radiographic results of MIS interbody fusion surgery are as favorable as those with conventional surgery regarding fusion, restoration of disc height, foraminal height, and lumbar lordosis. MIS-ALIF is more effective than MIS-TLIF for intervertebral disc height restoration and lumbar lordosis.

The Result of Minimal Invasive Anterior Lumbar Interbody Fusion with Posterior Lumbar Interbody Fusion on Degenerative Lumbar Flat Back Disease

STUDY DESIGN: Restrospective study. OBJECTIVES: We tried to find out the effects of minimal invasive anterior lumbar interbody fusion (ALIF) combined with posterior lumbar interbody fusion for degenerative lumbar flat back disease. SUMMARY OF LITERATURE REVIEW: ALIF combined with PLIF is effective in correcting lumbar lordosis. However, the complication rate with conventional ALIF is higher on the lower level. MATERIALS AND METHODS: 21 cases (9 men and 12 women, 46-83 years of age) of having undergone minimal invasive ALIF and PLIF due to degenerative flat back disease were reviewed. The follow-up period was an average of 23 months. We compared the pre-postoperative pain, the functional outcome, the correction of sagittal imbalance and lordotic angle. RESULTS: At final follow-up, 21 cases with the solid fusion experienced a great improvement in their lower back pain(VAS: 7.3 --> 2.6) and leg pain (VAS: 7.0 --> 2.7) and ODI(38.5 --> 18.1). And we experienced correction in sagital imbalance. On levels with anterior fusion, lordotic angle is corrected 6.3 degrees while on levels with posterior fusion, lordotic angle is corrected 9.7 degrees. Plumb line is corrected by 5.2cm, and no complication was found in the follow-up period. CONCLUSIONS: Combined surgery with minimal invasive anterior lumbar interbody fusion and posterior fusion is an effective procedure on patients who need long level surgery for correction of lumbar deformity and decompression.

Iliac Artery Thrombosis Due to Plaque Rupture During Performance of Anterior Lumbar Interbody Fusion: A Case Report

Anterior lumbar interbody fusion (ALIF) is a popular procedure that is used in spine surgery for treating disc herniation. Although this operation is usually safe, it can cause vascular injury, including arterial thrombosis. We report here on the case of 59-year-old woman who developed acute arterial thrombosis during ALIF. Toward the end of the operation, the somatosensory evoked potential signals decreased more than 50% in the left lower extremity, suggesting acute arterial occlusion. Therefore, a vascular surgeon was contacted and immediate thrombo-endarterectomy was performed. Thrombosis developed due to rupture of preexisting plaque during the arterial retraction. After the endarterectomy, the somatosensory evoked potentials signals and pulse were restored. To avoid vascular injury, preoperative evaluation of the vascular images and careful handling of the vessels during surgery are important. A vascular surgeon should be available not only in the event of complications, but such a surgeon should also be included from the planning of the operation.

Unexpected Disseminated Intravascular Coagulation after Venous Injury during Anterior Lumbar Interbody Fusion: A Case Report

Various complications related to anterior lumbar interbody fusion (ALIF) have been reported in the literature. However, disseminated intravascular coagulation (DIC) after venous injury during ALIF has not been previously reported. We describe a rare case of DIC after ALIF.

Anterior Lumbar Interbody Fusion with Percutaneous Pedicle Screw Fixation for the Treatment of Postoperative Pyogenic Spondylodiscitis

Deep wound infection is a serious surgical complication. The majority of patients with pyogenic spondylodiscitis can be treated non-surgically with antibiotics and immobilization. However, although surgical management of pyogenic spondylodiscitis continues to evolve, no consensus has yet been reached regarding the best surgical approaches and techniques. Anterior lumbar interbody fusion (ALIF) followed by percutaneous pedicle screw fixation (PPF) is an effective surgical option for treating postoperative pyogenic spondylodiscitis (PPS). In this report, we describe a case of PPS in a 64-year-old man who underwent ALIF with PPF.

Thrombosis of Left Common Iliac Artery Following Anterior Lumbar Interbody Fusion: Case Report and Review of Literatures

We report on a case of thrombosis of the left common iliac artery following anterior lumbar interbody fusion (ALIF) of L4-5 in a 79-year-old man with no previous medical problems, including peripheral vascular disease. After completing the ALIF procedure, the surgeon could not feel the pulsation of the left dorsalis pedis artery, and the oxygen saturation (SaO2) had fallen below 90% from pulse oxymetry on the left great toe. Thrombectomy was successfully performed after confirming the thrombus in the left common iliac artery using Computed Tomography (CT) angiography. Thrombosis of the common iliac artery is very rare following ALIF. However, delayed diagnosis can lead to disastrous outcome. Although elderly patients have no cardio-vascular disease or vessel calcification in pre-op evaluation, the possibility of a complication involving L4-5 should be considered.

The Ligamentotactic Effect on a Herniated Disc at the Level Adjacent to the Anterior Lumbar Interbody Fusion : Report of Two Cases

The authors report two cases of spontaneous regression of disc herniation at the level adjacent to the anterior lumbar interbody fusion (ALIF) level. This phenomenon may be due to the increased tension on the posterior longitudinal ligament (PLL) by appropriate restoration of the disc height and lumbar lordosis, which is a mechanism similar to ligamentotaxis applied to the thoracolumbar burst fracture.

Minimally invasive anterior approach to the lumbar spine / 한양의대학술지

A technique and clinical experiences of minimally invasive anterior lumbar interbody fusion ( mini-ALIF ) are reported. Despite its biomechanical advantages and high fusion rate, conventional ALIF needs a long skin incision and extensive dissection. Endoscopic approaches for ALIF seem to be associated with considerable technical difficulties, long operation time, and high complication rate even in collaboration with a laparoscopic surgeon. Mini-ALIF involves a standardized minimally invasive microsurgical retroperitoneal approach for L2-3 to L4-5, and transperitoneal approach for L5-S1. Mini-ALIF can be done through minimal skin incision(4-5cm) and blunt muscle dissection without abdominal muscle cutting. The surgical indications are degenerative disc diseases, disc herniations, degenerative spondylolisthesis, and iatrogenic postoperative instability including postoperative pseudarthrosis. Lumbar artificial disc replacement is a new indication to this technoque. Mini-ALIF provided sufficient operation space for lumbar interbody fusion. Consequently, operation time, bleeding, and postoperative morbidity of ALIF could be reduced.

A Morphometric Analysis of Neuroforamen in Grade I Isthmic Spondylolisthesis by Anterior Lumbar Interbody Fusion with Pedicle Screw Fixation

OBJECTIVES: The aim of this study was to evaluate the morphometric changes in neuroforamen in grade I isthmic spondylolisthesis by anterior lumbar interbody fusion (ALIF). METHODS: Fourteen patients with grade I isthmic spondylolisthesis who underwent single level ALIF with percutaneous pedicle screw fixation were enrolled. All patients underwent standing lateral radiography and magnetic resonance imaging (MRI) before surgery and at 1 week after surgery. For quantitative analysis, the foraminal height, foraminal width, epidural foraminal height, epidural foraminal width, and epidural foraminal area were evaluated at the mid-portion of 28 foramens using T2-weighted sagittal MRI. For qualitative analysis, degree of neural compression in mid-portion of 28 foramens was classified into 4 grades using T2-weighted sagittal MRI. Clinical outcomes were assessed using Visual Analogue Sale (VAS) scores for leg pain and Oswestry disability index before surgery and at 1 year after surgery. RESULTS: The affected levels were L4-5 in 10 cases and L5-S1 in 4. The mean foraminal height was increased (p<0.001), and the mean foraminal width was decreased (p=0.014) significantly after surgery. The mean epidural foraminal height (p<0.001), epidural foraminal width (p<0.001), and epidural foraminal area (p<0.001) showed a significant increase after surgery. The mean grade for neural compression was decreased significantly after surgery (p<0.001). VAS scores for leg pain (p=0.001) and Oswestry disability index (p=0.001) was decreased significantly at one year after surgery. CONCLUSION: Foraminal stenosis in grade I isthmic spondylolisthesis may effectively decompressed by ALIF with percutaneous pedicle screw fixation.

Anterior Lumbar Interbody Fusion with Pedicle Screw Fixation for Elderly Isthmic Spondylolisthesis

OBJECTIVE: The surgical outcome of anterior lumbar interbody fusion(ALIF) with pedicle screw fixation for elderly isthmic spondylolisthesis was analyzed. METHODS: Consecutive nineteen elderly patients (aged 65 years or more) with isthmic spondylolisthesis (Grade I or II) who underwent single level ALIF with pedicle screw fixation in 2002 were analyzed. Using clinical chart and mailed questionnaires, preoperative and postoperative Visual Analogue Scale(VAS) of back and leg pain and postoperative Macnab criteria were evaluated. RESULTS: The mean age at the time of operation was 68.4 years (range 65 to 78 years). Twelve patients underwent ALIF with percutaneous pedicle screw fixation. Seven patients underwent ALIF followed by posterior decompression and pedicle screw fixation. The postoperative complication rate was 10.5% (wound dehiscence in 1 patient and incisional hernia in 1 patient). There was no postoperative major morbidity or mortality. At a mean follow-up duration of 30.7 months (range 25 to 35 months), 93.3% (14/15) of the patients showed excellent or good outcomes in terms of Macnab criteria. The mean VAS scores of back pain and leg pain significantly decreased after surgery. CONCLUSION: ALIF with pedicle screw fixation yielded favorable results for elderly isthmic spondylolisthesis in selected cases.

Isthmic Spondylolisthesis Associated with Foraminal Disc Herniation Treated by Anterior Lumbar Interbody Fusion

A 45-year-old man presented with lower back pain and pain in the right leg of 3years duration. A plain radiographic examination revealed grade I isthmic spondylolisthesis, with instability at L4-5. Computed tomography and magnetic resonance imaging demonstrated bilateral foraminal stenosis, with soft foraminal disc herniation on the right side at the L4-5 level. He underwent anterior lumbar interbody fusion(ALIF) with percutaneous posterior fixation(PF) at the L4-5 level. Without removing the posterior bony structures, removal of foraminal disc herniation and reduction of spondylolisthesis were successfully performed using ALIF with percutaneous PF. When there is no hard disc herniation or lateral recess stenosis, ALIF with percutaneous PF can be one of the treatment options for isthmic spondylolisthesis, even in the presence of foraminal disc herniation, as in our case.

A Retrospective Study of the Fusion Rate and Clinical Outcome after Mini-open ALIF using Paired Stand-alone Rectangular Cages

OBJECTIVE: We conduct a study to determine the fusion rate and clinical outcome after mini-open anterior lumbar interbody fusion(ALIF) in selected patients with a degenerative lumbar disc disease. METHODS: Ninety-four patients underwent the ALIF procedure between November 2000 and June 2002. The subjects were 23 men and 71 women, with a mean age of 52 years(range, 25-72). The mean follow-up duration was 21 months(range, 13-32). Clinical outcome was assessed using the modified Japanese Orthopedic Association(JOA) low back pain score and the 10-point visual analogue scale(VAS). Radiologic evaluation was performed using plain radiographs. The intervertebral disc height was measured and expressed as the percentage of the total disc height to the AP diameter of the vertebral body. RESULTS: The overall fusion rate in our series was 88.3%. The mean preoperative JOA score was 8.3+/-1.6. At the last follow up visit, the mean JOA score was increased to 13.1+/-1.1, respectively(p<0.001). VAS showed a similar result to JOA score(p<0.001). The preoperative intervertebral disc height was 36.7+/-9.9%. Postoperatively, the disc height spread to 53.3+/-10.8% one month after surgery, but diminished to 46.6+/-11.9% at the last follow-up. CONCLUSION: Our study shows that ALIF using stand-alone rectangular cages remains effective for the indicated conditions in patients with a degenerative lumbar disc disease.

Anterior Lumbar Interbody Fusion Using BAK Cage for Treatment of Failed Back Surgery Syndrome

OBJECTIVE: To evaluate the role of anterior lumbar interbody fusion in treatment of failed back surgery syndrome, the authors present a retrospectively analysis of the clinical & radiological results of anterior lumbar interbody fusion. METHODS: Between September 2000 and September 2001, twenty two patients underwent anterior lumbar interbody fusion for treatment of failed back surgery syndrome. We analyzed clinical & radiological changes. The mean follow-up period was 19 months. RESULTS: Overall satisfactory outcome was 90%. The mean VAS was changed from 8.3 to 3.7. The mean Oswestry Disability Index(%) was changed from 70 to 33. The fusion rate was 86%. There were 2 complications; wound infection, sympathetic dysfunction. CONCLUSION: We conclude that the anterior lumbar interbody fusion seems to be a safe and favorable method in treating selective patients with failed back surgery syndrome.

Anterior Lumbar Interbody Fusion for Focal Type of Degenerative Flat Back: Preliminary Report

OBJECTIVE: The purpose of this study is to determine the efficacy of anterior lumbar interbody fusion(ALIF) for the patients with focal type of degenerative flat back. METHODS: The authors reviewed clinical and radiologic data of 16 patients with focal type of degenerative flat back who underwent ALIF during the period between December 1999 and November 2000. The operation procedure was ALIF using titanium or carbon fiber cages of lordotic angle, which were filled with allograft or autograft mixed with allograft through minilaparotomy. RESULTS: The majority of the patients were female(15 female: 1 male) and the mean age was 60.1 years. Six patients were operated on one level, ten on two levels. The mean follow up period was 10.7 months. The mean operation time was 131minutes and the average estimated blood loss was 133ml. Transfusion was not needed in any case. The mean preoperative lumbar lordotic angle was 4.1 degree(-7.4-41.6) and improved to 17.5 degree(-4.5-41.9) postoperatively. Radiological fusion was achieved in 13 patients(81%). The Oswestry disability index score improved from 62.5% to 23.9% and the patient's subjective improvement rate was 80%. Complications were infection in one patient, incisional hernia in one, symptomatic pseudoarthrosis in one and transient sympathetic disturbance in left leg in three. CONCLUSION: In a subset of the patients with degenerative flat back who showed disc degeneration in one or two levels, ALIF using cages improved patient's symptoms effectively. It seems that ALIF through minilaparotomy can be one of the surgical options in the treatment of the focal type of degenerative flat back.

Change in Sagittal Plane of the Lumbar Spine in Patients with Anterior Lumbar Interbody Fusion and Pedicle Instrumentation and its Influencing Factors / 대한정형외과학회잡지

PURPOSE: To evaluate long-term changes in sagittal plane of the lumbar spine in patients with anterior lumbar interbody fusion and pedicle instrumentation and to determine the influencing factors. MATERIALS AND METHODS: Eighty-seven patients underwent single level anterior lumbar interbody fusion with pedicle instrumentation. Each patient's disc space height and segmental sagittal angle was measured preoperatively, immediate postoperatively, and at the last follow-up. RESULTS: Immediate postoperative radiographs demonstrated an average increase in disc space height of 2.8 mm. The follow-up radio-graphic evaluation showed an average decrease of 4.2 mm from the immediate postoperative period and 1.4 mm from the preoperative period. Sagittal angles of the preoperative, postoperative and follow-up period were 10.3 degrees, 14.2degrees and 10.4degrees, respectively. Decrease in disc space height correlated with patient's age and the amount of distraction by the operation. CONCLUSION: Our data demonstrated that the change in the sagittal plane obtained by anterior lumbar interbody fusion with pedicle instrumentation is lost in the postoperative period. Most levels return to their original height or less. This finding suggests that a disc space distraction by this technique in elderly patients with kyphotic deformity is not reliable.