Multi-modal pain control regimen for anterior lumbar fusion drastically reduces in-hospital opioid consumption.

BACKGROUND: The opioid epidemic is at epic proportions currently in the United States. Exposure to opioids for surgery and subsequent postoperative pain management is a known risk factor for opioid dependence. In addition, opioids can have a negative impact on multiple aspects including clinical outcomes, length of hospital stay, and overall cost of care. Thus, the greatest effort to reduce perioperative opioid use is necessary and a multimodal pain control (MMPC) has been gaining popularity. However, its efficacy in spine surgery is not well known. We aimed to evaluate the efficacy of a MMPC protocol in patients undergoing lumbar single-level anterior lumbar interbody fusion (ALIF). METHODS: This is a retrospective comparative study. From a prospective, single-surgeon, surgical database, consecutive patients undergoing single-level ALIF with or without subsequent posterior fusion for degenerative lumbar conditions were identified before and after initiation of the MMPC protocol. The MMPC protocol consisted of a preoperative oral regimen of cyclobenzaprine (10 mg), gabapentin (600 mg), acetaminophen (1 g), and methadone (10 mg). Postoperatively they received a bilateral transverse abdominis plane block with 0.5% Ropivacaine prior to extubation. We compared in-hospital opioid consumption between the MMPC and non-MMPC cohorts as well as baseline demographic, the length of hospital stay, cost, and rate of postoperative ileus. Opioid consumption was calculated and normalized to the morphine milligram equivalents (MMEs). RESULTS: In total, 68 patients in the MMPC cohort and 39 in the non-MMPC cohort were identified. There was no difference in baseline demographics including sex, body mass index, smoking status, or preoperative opioid use between the two groups. Although there was no difference in the MMEs on the day of surgery (58.5 vs. 66.9, P=0.387), cumulative MMEs each day after surgery was significantly lower in the MMPC cohort, with final cumulative MMEs being reduced by 62% (120.2 vs. 314.8, P<0.001). There was no difference in postoperative ileus, length of stay, and hospital costs. CONCLUSIONS: The use of a MMPC protocol in patients undergoing single-level ALIF for degenerative conditions reduced opioid consumption starting on the first day after surgery, resulting in a cumulative reduction of 62%.

Surgical results of a one-stage combined anterior lumbosacral fusion and posterior percutaneous pedicle screw fixation.

OBJECTIVES: Lumbosacral fusion through either an anterior or a posterior approach to achieve good lordosis and stability is always a challenging surgical operation and is often accompanied by a higher rate of pseudarthrosis than when other lumbar segments are involved. This study evaluated the clinical and radiological results of lumbosacral fusions achieved through a combined anterior and posterior approach. MATERIALS AND METHODS: From June 2008 to 2012, 20 patients who had L5-S1 instability and stenosis were consecutively treated, first by anterior interbody fusion using an allogenous strut bone graft through the pararectus approach and then by posterior pedicle screw fixation. A minimum of 1-year of clinical and radiological follow-up was conducted. Intraoperative blood loss, surgical time, and any surgery-related complications were recorded. Clinical outcomes were assessed using a visual analog scale (VAS) and the patient's Oswestry Disability Index (ODI) score. After 1 year, radiological outcomes were assessed by analyzing pelvic incidence, lumbar lordosis, and segmental lordosis using static plain films, while fusion stability was assessed using dynamic plain films. RESULTS: The mean operative time and blood loss were 215 min and 325 cc, respectively. After 1 year, the VAS and ODI scores had significantly improved, and stable fusion with good lordotic curvature was obtained in all cases. CONCLUSION: The surgical results of the combined procedure are satisfactory in terms of the functional and radiological outcomes. Our method offers advantages regarding both anterior fusion and posterior fixation.

The safe use of long screws in L5/S1 stand-alone anterior interbody fusion for olisthesis cases.

BACKGROUND: Stand-alone anterior interbody fusion (STALIF) with poly-ether-ether-ketone (PEEK) cages could offer a treatment option in olisthesis cases. The fixation of the PEEK-cage at the L5/S1 inferior endplate with long divergent screws however might endanger neural sacral structures, especially the S1 nerve root. If shorter screws are used, the achieved bony purchase might not be sufficient to resist the pull out and shear forces at the lumbosacral junction. The aim of the present investigation was to evaluate the use of long screws in PEEK-cages for olisthesis cases at the L5/S1 segment and its neurological complications. MATERIAL AND METHODS: 11 Patients (6 males) with a mean age of 47(± 15.1) years between 2013-2015 designated for an STALIF at the L5/S1 level were consecutively included in the present study. All patients had a Grade 1 or 2 slippage according to Meyerding. PEEK cages (SynFix-LR®, Depuy Synthes) were implanted with 30mm screws at the baseplate of L5/S1 in all patients. Perioperative and postoperative long-term complications were evaluated. Furthermore, radiological follow-up was performed (CT-scan at 6 months, X-ray at 6, 12 and 24 months). RESULTS: 6 patients suffered from an isthmic, 1 from a degenerative olisthesis. 4 patients with iatrogenic spondylolisthesis were included. Pre-operative radiculopathy was noted in 10 patients. 9 patients with pre-operative radiculopathy showed relief of symptoms until the last follow-up after 24 months. Fusion was achieved in all patients after 6 months. No screw-displacement, breakage or violation of the neural foramen was noted. Furthermore, no implant failure or pull-out fractures were seen. CONCLUSION: In this investigation, no complication due to the use of long divergent locking screws was noted. In addition, the majority of patients showed permanent relief of radiculopathy symptoms at the 2 years follow-up. This study demonstrates the safe usage of long divergent locking screws in the baseplate of L5/S1 in anterior interbody fusion at the L5/S1 level.

The role of sacral slope in lumbosacral fusion: a biomechanical study.

OBJECT: Abnormal sacral slope (SS) has shown to increase progression of spondylolisthesis, yet there exists a paucity in biomechanical studies investigating its role in the correction of adult spinal deformity, its influence on lumbosacral shear, and its impact on the instrumentation selection process. This in vitro study investigates the effect of SS on 3 anterior lumbar interbody fusion constructs in a biomechanics laboratory. METHODS: Nine healthy, fresh-frozen, intact human lumbosacral vertebral segments were tested by applying a 550-N axial load to specimens with an initial SS of 20° on an MTS Bionix test system. Testing was repeated as SS was increased to 50°, in 10° increments, through an angulated testing fixture. Specimens were instrumented using a standalone integrated spacer with self-contained screws (SA), an interbody spacer with posterior pedicle screws (PPS), and an interbody spacer with anterior tension band plate (ATB) in a randomized order. Stiffness was calculated from the linear portion of the load-deformation curve. Ultimate strength was also recorded on the final construct of all specimens (n = 3 per construct) with SS of 40°. RESULTS: Axial stiffness (N/mm) of the L5-S1 motion segment was measured at various angles of SS: for SA 292.9 ± 142.8 (20°), 277.2 ± 113.7 (30°), 237.0 ± 108.7 (40°), 170.3 ± 74.1 (50°); for PPS 371.2 ± 237.5 (20°), 319.8 ± 167.2 (30°), 280.4 ± 151.7 (40°), 233.0 ± 117.6 (50°); and for ATB 323.9 ± 210.4 (20°), 307.8 ± 125.4 (30°), 249.4 ± 126.7 (40°), 217.7 ± 99.4 (50°). Axial compression across the disc space decreased with increasing SS, indicating that SS beyond 40° threshold shifted L5-S1 motion into pure shear, instead of compression-shear, defining a threshold. Trends in ultimate load and displacement differed from linear stiffness with SA > PPS > ATB. CONCLUSIONS: At larger SSs, bilateral pedicle screw constructs with spacers were the most stable; however, none of the constructs were significantly stiffer than intact segments. For load to failure, the integrated spacer performed the best; this may be due to angulations of integrated plate screws. Increasing SS significantly reduced stiffness, which indicates that surgeons need to consider using more aggressive fixation techniques.

Prospective randomized controlled trial of The Stabilis Stand Alone Cage (SAC) versus Bagby and Kuslich (BAK) implants for anterior lumbar interbody fusion.

BACKGROUND: Degenerative disc disease is common and debilitating for many patients. If conservative extensive care fails, anterior lumbar interbody fusion has proven to be an alternative form of surgical management. The Stabilis Stand Alone Cage(SAC) was introduced as a method to obtain stability and fusion. The purpose of this study was to determine whether the Stabilis Stand Alone Cage (SAC) is comparable in safety and efficacy to the Bagby and Kuslich (BAK) device. METHODS: As part of a prospective, randomized, controlled FDA trial, 73 patients underwent anterior interbody fusion using either the SAC(56%) or the BAK device (44%). RESULTS: Background characteristics were similar between the two groups. There was no significant difference between the SAC and BAK groups in mean operative time or mean blood loss during surgery. Adverse event rates did not differ between the groups. Assessment of plain radiographs could not confirm solid fusion in 63% of control and 71% of study patients. Functional scores from Owestry and SF-36 improved in both groups by the two-year follow-up. There were no significant differences between the SAC and BAK patients with respect to outcome. CONCLUSIONS: Both the Stabilis Stand Alone Cage and the BAK Cage provided satisfactory improvement in function and pain relief, despite less than expected radiographic fusion rates. The apparent incongruency between fusion rates and functional outcomes suggests that either radiographs underestimate the true incidence of fusion, or that patients are obtaining good pain relief and improved function despite a lower rate of fusion than previously reported. This was a Level III study.

MRI measurement of neuroforaminal dimension at the index and supradjacent levels after anterior lumbar interbody fusion: a prospective study.

BACKGROUND: Anterior interbody fusion has previously been demonstrated to increase neuroforaminal height in a cadaveric model using cages. No prior study has prospectively assessed the relative change in magnetic resonance imaging (MRI) demonstrated neuroforaminal dimensions at the index and supradjacent levels, after anterior interbody fusion with a corticocancellous allograft in a series of patients without posterior decompression. The objective of this study was to determine how much foraminal dimension can be increased with indirect foraminal decompression alone via anterior interbody fusion, and to determine the effect of anterior lumbar interbody fusion on the dimensions of the supradjacent neuroforamina. METHODS: A prospective study comparing pre- and postoperative neuroforaminal dimensions on MRI scan among 26 consecutive patients undergoing anterior lumbar interbody fusion without posterior decompression was performed. We studies 26 consecutive patients (50 index levels) that had undergone anterior interbody fusion followed by posterior pedicle screw fixation without distraction or foraminotomy. We used preoperative and postoperative MRI imaging to assess the foraminal dimensions at each operated level on which the lumbar spine had been operated. The relative indirect foraminal decompression achieved was calculated. The foraminal dimension of the 26 supradjacent untreated levels was measured pre- and postoperatively to serve as a control and to determine any effects after anterior interbody fusion. RESULTS: In this study, 8 patients underwent 1 level fusion (L5-S1), 12 patients had 2 levels (L4-S1) and 6 patients had 3 levels (L3-S1). The average increase in foraminal dimension was 43.3% (p < 0.05)-19.2% for L3-4, 57.1% for L4-5, and 40.1% for L5-S1. Mean pre- and postoperative supradjacent neuroforaminal dimension measurements were 125.84 mm(2) and 124.89 mm(2), respectively. No significant difference was noted (p > 0.05). CONCLUSIONS: Anterior interbody fusion with a coriticocancellous allograft can significantly increase neuroforaminal dimension even in the absence of formal posterior distraction or foraminotomy; anterior interbody fusion with a coriticocancellous allograft has little effect on supradjacent neuroforaminal dimensions.

MRI Measurement of Neuroforaminal Dimension at the Index and Supradjacent Levels after Anterior Lumbar Interbody Fusion: A Prospective Study

BACKGROUND: Anterior interbody fusion has previously been demonstrated to increase neuroforaminal height in a cadaveric model using cages. No prior study has prospectively assessed the relative change in magnetic resonance imaging (MRI) demonstrated neuroforaminal dimensions at the index and supradjacent levels, after anterior interbody fusion with a corticocancellous allograft in a series of patients without posterior decompression. The objective of this study was to determine how much foraminal dimension can be increased with indirect foraminal decompression alone via anterior interbody fusion, and to determine the effect of anterior lumbar interbody fusion on the dimensions of the supradjacent neuroforamina. METHODS: A prospective study comparing pre- and postoperative neuroforaminal dimensions on MRI scan among 26 consecutive patients undergoing anterior lumbar interbody fusion without posterior decompression was performed. We studies 26 consecutive patients (50 index levels) that had undergone anterior interbody fusion followed by posterior pedicle screw fixation without distraction or foraminotomy. We used preoperative and postoperative MRI imaging to assess the foraminal dimensions at each operated level on which the lumbar spine had been operated. The relative indirect foraminal decompression achieved was calculated. The foraminal dimension of the 26 supradjacent untreated levels was measured pre- and postoperatively to serve as a control and to determine any effects after anterior interbody fusion. RESULTS: In this study, 8 patients underwent 1 level fusion (L5-S1), 12 patients had 2 levels (L4-S1) and 6 patients had 3 levels (L3-S1). The average increase in foraminal dimension was 43.3% (p 0.05). CONCLUSIONS: Anterior interbody fusion with a coriticocancellous allograft can significantly increase neuroforaminal dimension even in the absence of formal posterior distraction or foraminotomy; anterior interbody fusion with a coriticocancellous allograft has little effect on supradjacent neuroforaminal dimensions.

A surgical option for multilevel anterior lumbar interbody fusion with ponte osteotomy to achieve optimal lumbar lordosis and sagittal balance.

OBJECTIVE: To document lumbar lordosis (LL) of the spine and its change during surgeries with the different height but the same angle setting of the anterior cage. Additionally, we attempted to determine if sufficient LL is achieved at different cage heights and to quantify the change in LL during multi-level anterior lumbar interbody fusion (ALIF). METHODS: The medical records and radiographs of 42 patients who underwent more than 2 level ALIFs between 2008 and 2009 were retrospectively reviewed. We evaluated 3 parameters seen on lateral whole spine radiographs : LL, pelvic incidence (PI), and sagittal vertical axis (SVA). The mean follow-up time was 28.1 months and the final follow-up radiographs of all patients were reviewed at least 2 years after surgery. Statistical analysis was performed using the paired t-tests. RESULTS: Lumbar lordosis had changed up to 30 degrees immediately and 2 years after surgery (preoperative mean LL, SVA : 22.45 degrees, 112.31 mm; immediate postoperative mean LL, SVA : 54.45 degrees, 37.36 mm; final follow-up mean LL, SVA : 49.56 degrees, 26.95 mm). Our goal of LL is to obtain as much PI as possible, preoperative mean PI value was 55.38±3.35. The pre-operative and two year post-surgery follow-up mean of the Japanese Orthopedic Association score were 9.2±0.6 and 13.2±0.6 (favorable outcome rate : 95%), respectively. In addition, we were able to obtain good clinical outcomes and sagittal balance with a subsidence rate of 22.7%. CONCLUSION: We were able to achieve sufficient LL, such that it was similar to the PI, utilizing multi-level ALIF with the use of a tall cage with the same angle setting of the cage. We have found out that achieving sufficient lumbar lordosis and sagittal balance require an anterior lumbar cage with high angle and height.

A Surgical Option for Multilevel Anterior Lumbar Interbody Fusion with Ponte Osteotomy to Achieve Optimal Lumbar Lordosis and Sagittal Balance

OBJECTIVE: To document lumbar lordosis (LL) of the spine and its change during surgeries with the different height but the same angle setting of the anterior cage. Additionally, we attempted to determine if sufficient LL is achieved at different cage heights and to quantify the change in LL during multi-level anterior lumbar interbody fusion (ALIF). METHODS: The medical records and radiographs of 42 patients who underwent more than 2 level ALIFs between 2008 and 2009 were retrospectively reviewed. We evaluated 3 parameters seen on lateral whole spine radiographs : LL, pelvic incidence (PI), and sagittal vertical axis (SVA). The mean follow-up time was 28.1 months and the final follow-up radiographs of all patients were reviewed at least 2 years after surgery. Statistical analysis was performed using the paired t-tests. RESULTS: Lumbar lordosis had changed up to 30 degrees immediately and 2 years after surgery (preoperative mean LL, SVA : 22.45 degrees, 112.31 mm; immediate postoperative mean LL, SVA : 54.45 degrees, 37.36 mm; final follow-up mean LL, SVA : 49.56 degrees, 26.95 mm). Our goal of LL is to obtain as much PI as possible, preoperative mean PI value was 55.38+/-3.35. The pre-operative and two year post-surgery follow-up mean of the Japanese Orthopedic Association score were 9.2+/-0.6 and 13.2+/-0.6 (favorable outcome rate : 95%), respectively. In addition, we were able to obtain good clinical outcomes and sagittal balance with a subsidence rate of 22.7%. CONCLUSION: We were able to achieve sufficient LL, such that it was similar to the PI, utilizing multi-level ALIF with the use of a tall cage with the same angle setting of the cage. We have found out that achieving sufficient lumbar lordosis and sagittal balance require an anterior lumbar cage with high angle and height.

The Availability of Autogenous Bicortical Iliac Bone Graft in Anterior Cervical Interbody Fusion

STUDY DESIGN: Retrospective study. OBJECTIVES: To demonstrate the fusion rate, degree of subsidence and donor site morbidity of anterior cervical interbody fusion with autogenous bicortical iliac bone graft and anterior cervical locking plate. SUMMARY OF THE LITERATURE REVIEW: In anterior cervical discectomy and fusion with autogenous tricortical iliac bone graft, a large percentage of patients report chronic donor site pain. MATERIALS AND METHODS: Retrospective research was done for 39 patients who underwent anterior cervical interbody fusion with autogenous bicortical iliac bone graft, from January 2006 to July 2011, with a follow up period of longer than 1 year. Fusion rates and subsidece of the graft is estimated with radiographs. Neck pain and donor site pain was estimated with visual analogue scale (VAS) and dysfunction was estimated with the neck disability index (NDI). RESULTS: A 95% of patients who underwent anterior cervical interbody fusion with autogenous bicortical iliac bone graft revealed definitive fusion with little amount of subsidence. The mean VAS score was 0.7 on the donor site and the mean NDI score was 3.8 at the final visit. There was excellent clinical outcome without complication at the donor site or the recipient site. CONCLUSIONS: Anterior cervical interbody fusion with autogenous bicortical iliac bone graft showed high fusion rates and minimal subsidence with excellent clinical outcomes. Therefore, bicortical iliac bone graft is an effective operational procedure in anterior cervical interbody fusion.

The Changes in Neural Foramen Shown on Computed Tomography Depending on the Changes in the Height of Intervertebral Disc after Anterior Cervical Discectomy and Fusion (ACDF)

STUDY DESIGN: A prospective radiological assessment. OBJECTIVES: Changes in the height, area, and width--captured using computed tomography (CT)--of the neural foramen with respect to changes in the intervertebral disc height, after undergoing an anterior cervical disc removal and fusion procedure. SUMMARY OF LITERATURE REVIEW: The multiple authors of this study, by obtaining central canal and area of neural foramen by increasing the disc spacing height and area of the neural foramen, attempted to assess the height increase of disc spacing. It is necessary to consider the synergistic effects of decompression through dissection of the posterior longitudinal ligament (PLL). MATERIALS AND METHODS: The authors studied 17 patient cases that underwent one segment anterior cervical discectomy and fusion (ACDF) for degenerative cervical disease from June 2006 to March 2007. All patient cases underwent autogenous iliac bone graft or cage insertion with plate fixation procedure. We measured the areas of the neural foramen, heights of the vertebra body above and below the removed intervertebral disc with CT before and after ACDF. Radiographic measurements were averaged. RESULTS: Among the 17 cases, the height of the cervical disc increased in 15 cases and decreased in 2 cases. The heights of the neural foramen increased in 19 cases and showed no changes in 13 cases. The areas of the neural foramen increased in 23 cases and decreased in 6 cases. The heights of vertebral body above and below the removed disc increased by 5.4% (p=0.734), and the heights of the neural foramen increased by 13.3% (p=0.002). The area of the neural foramen increased by 13.6% (p=0.192). The widths of the neural foramen increased by 2.3% (p=0.586). The intervertebral disc height, neural foramen height, and neural foramen area increased by 39.6%, 8.4%, and 17.9%, respectively, after a 2mm lengthening of bone transplant. The intervertebral disc height, neural foramen height, and neural foramen area increased by 59.8%, 22.9%, and 10.3%, respectively, after a 3mm lengthening of bone transplant. The height and area of neural foramen increased by 18.3% and 18.2%, respectively, after the PLL removal and dissection. CONCLUSIONS: The follow-up observations of the intervertebral disc height, neural foramen height, and neural foramen area showed increases after one segment ACDF in cervical disease cases, when compared to the preoperative radiographic findings. As the height of bone transplant increased, the intervertebral disc height, neural foramen height, and neural foramen area increased. The neural foramen height and neural foramen area significantly increased, when PLL was dissected.

Efficiency of Anterior Interbody Fusion using Cage Packed with DBM in the Distractive Flexion Injury of Cervical Spine: Demineralized Bone Matrix vs Autoiliac Cancellous Bone

STUDY DESIGN: This is a retrospective study. OBJECTIVES: We wanted to evaluate the effectiveness and safety of a PEEK cage filled with DBM in patients with a distractive flexion injury of the cervical spine. SUMMARY OF LITERATURE REVIEW: AIF of the cervical spine using an autoiliac bone graft and plate fixation is known to be an effective treatment for traumatic injuries. However, the complications arising from the donor site are troublesome, and so fusion with cage is an alternative treatment. MATERIALS AND METHODS: We analyzed 32 cases (22 males and 10 females) with distractive flexion injury of the cervical spine. They underwent anterior decompression and interbody fusion with a PEEK cage and anterior plate fixation. In 18 patients, the cage was filled with autogenous iliac bone (Group I), and for the other 10 the cages were filled with DBM (Group II). RESULTS: All the cases in Group I and Group II achieved fusion except for one case of nonunion in group II. The anterior and posterior vertebral heights of the fused segments of group II were decreased more than those of group I, resulting a statistical difference (p=0.003). The changes of segmental lordosis (p=0.69) and the neurologic status (p=0.22) showed no statistical difference between the two groups. CONCLUSIONS: AIF using a PEEK cage filled with DBM and plate fixation showed no significant clinical differences compared to the case of iliac bone autografting. However, from a radiologic perspective, the time to achieve union was extensive and a case of nonunion was also observed. Therefore, many considerations are necessary when using DBM as a replacement for iliac bone autografting and further research should be done on this subject.

Efficiency of Anterior Interbody Fusion using Cage and Plate in the Distractive Flexion Injury of Cervical Spine : Cage vs Tricortical Autoiliac Bone / 대한척추외과학회지

STUDY DESIGN: This is a retrospective study OBJECTIVES: We wanted to evaluate the effectiveness and safety of anterior interbody fusion (AIF) using cage and plate fixation for treating distractive flexion injury of the cervical spine according to the radiological and clinical outcomes. SUMMARY OF THE LITERATURE REVIEW: AIF of the cervical spine using autoiliac bone and plate fixation is known as an effective method for treating not only degenerative disease, but also trauma as well. However, the problem lies in the complications that occur at the donor site. To avoid these complications, the fusion method using a cage is becoming more frequently used, but there are not many reports on using a cage and plate for treating trauma in the cervical spine. MATERIALS AND METHODS: We retrospectively analyzed 47 patients with distractive flexion injury of the cervical spine and who underwent anterior decompression and interbody fusion with a autoiliac bone graft and plate fixation (Group I, 32 patients) or who underwent anterior decompression and interbody fusion with cage and plate fixation (Group II, 15 patients). We statistically analyzed the changes of the segmental lordosis, the fused segmental body height, the fusion rate on plain radiography and the neurologic recovery with using an ASIA scoring system. RESULTS: All the cases were fused by 12.6+/-2.5weeks after operation. The changes of segmental lordosis shows no statistical difference between the two groups (p=0.69). The anterior and posterior vertebral heights of the fused segments of Group I were more decreased than those of Group II, and there was a statistical difference between the two groups (p=0.03, 0.04). The initial and last follow up neurologic statuses were not statistically difference between the two groups (p=0.11) CONCLUSIONS: For the treatment of fracture-dislocation injury in the cervical spine, AIF using a PEEK cage filled with autoiliac bone and plate fixation is an effective method with the least possibility of complications at the donor site, and at the same time, this surgical method shows equally satisfactory results, both radiologically and clinically, as fusion with using a tricortical autoiliac bone graft.

Anterior Decompression and Fusion in the Treatment of Single-level Cervical Disc Herniation: Plate Fixation vs Cage / 대한척추외과학회지

STUDY DESIGN: This is a retrospective study. OBJECTIVES: We analyzed the radiological and clinical results to verify the efficacy of anterior interbody fusion with using cages gradually increases in the treatment of cervical radiculopathy. SUMMARY OF LITERATURE REVIEW: Anterior cervical decompression and fusion is well accepted treatments for cervical radiculopathy. Performing anterior interbody fusion using cages has recently gradually increased to minimize the extent of surgery. While there are numerous reports on the primary stabilizing effects of the cervical cages, little is known about the subsidence behavior of such cages in vivo. MATERIALS AND METHODS: We retrospectively analyzed 38 patients with cervical disc herniation who underwent anterior decompression and interbody fusion with autoiliac bone graft and plate fixation (Group I, 21 patients) or who underwent with standalone cage (Group II, 17 patients). We statistically analyzed the changes of the cervical lordosis, the segmental lordosis, the vertebral body height, the fusion rate on the plain x-ray and the clinical results with using a pain visual analogue scale. RESULTS: All the cases were fused by 11.2+/-2.7 weeks after operation. The changes of the cervical lordosis and segmental lordosis show no statistically significant difference between the two groups (p=0.07, 0.66). The anterior and posterior vertebral heights of the fused segments of group II were more decreased than those of group I, but there was no statistically difference between the two groups (p=0.06, 0.30). The clinical results were not statistically difference between the two groups (p=0.64, 0.45). CONCLUSIONS: Implantation of autoiliac cancellous bone impacted stand-alone cages or on a tricortical iliac crest autograft after anterior decompression was safe and reliable options for the treatment of cervical disc herniation that causes single level radiculopathy. Both procedures produced equally satisfying clinical and radiological results, leading to a high fusion rate and they maintained the intervertebral height.

Anterior debridement and strut graft with pedicle screw fixation for pyogenic spondylitis.

STUDY DESIGN: A retrospective study. PURPOSE: We evaluated the results of the use of anterior debridement and interbody fusion followed by posterior spinal instrumentation. OVERVIEW OF LITERATURE: An early diagnosis of pyogenic spondylitis is difficult to obtain. The disease can be treated with various surgical methods (such as anterior debridement and bone graft, anterior instrumentation, and posterior instrumentation). METHODS: This study included 20 patients who received anterior debridement and interbody fusion with strut bone graft followed by posterior spinal fusion for pyogenic spondylitis between 1996 and 2005. We analyzed the culture studies, the correction of the kyphotic angle, blood chemistry, the bony union period, and the amount of symptom relief. RESULTS: In terms of clinical symptoms relief, eight patients were grouped as "excellent", eleven patients as "good", and one patient as "fair". The vertebral body cultures were positive in 14 patients showing coagulase (-) streptococcus and S. aureus. The average times for normalization of the erythrocyte sedimentation rate and C-reactive protein level were 3.3 and 1.9 months, respectively. Four months was required for bony union. For complications, meralgia paresthetica was found in two cases. CONCLUSIONS: Due to early ambulation and the correction of the kyphotic angle, anterior interbody fusion with strut bone graft and posterior instrumentation could be another favorable method for the treatment of pyogenic spondyulitis.

The Comparison of Changes in the Dimensions of the Intervertebral Disc and Neural Foramen between Anterior Lumbar Interbody Fusion and Posterolateral Fusion in the Lumbar Spine / 대한척추외과학회지

STUDY DESIGN: A prospective radiologic assessment. OBJECTIVES: To compare the changes of dimensions of the intervertebral disc and neural foramen between the anterior lumbar interbody fusion and the posterolateral fusion in the lumbar spine. SUMMARY OF LITERATURE REVIEW: There are few reports comparing an anterior lumbar interbody fusion with pedicle screw fixation and a posterolateral fusion with pedicle screw fixation. MATERIALS AND METHODS: We studied 62 patients with degenerative lumbar diseases who underwent minimal anterior lumbar interbody fusion with pedicle screw fixation (group I, 40 patients) or who underwent posterolateral fusion with pedicle screw fixation (group II, 22 patients). We measured the height of disc and the height, width, and area of the neural foramen measured in 1-mm reconstructive sagittal images of computed tomography before and 6 months after the operation. The factors were independently measured by three different observers. RESULTS: Disc height was increased by a mean of 39.1+/-3.28% in group I and 3.1+/-2.99% in group II. The height of the neural foramen was increased by a mean of 18.7+/-4.21% in I and 1.0+/-2.34% in II. The area of neural foramen was increased by a mean of 21.5+/-3.50% in I and -2.1+/-4.39% in II, with significant differences between groups in all parameters. CONCLUSION: The minimal anterior lumbar interbody fusion with pedicle screw fixation was superior to posterolateral fusion with pedicle screw fixation for increasing disc height and the height and area of neural foramen.

The Changes in the Dimensions of Neural Foramen After Anterior Interbody Fusion in the Spondylolisthesis / 대한척추외과학회지

STUDY DESIGN: A prospective radiological assessment was performed using computerized tomography measurements. OBJECTIVES: The aim of this study was to assess the changes in the dimensions of the neural foramen after anterior interbody fusion with posterior fixation in spondylolisthesis. SUMMARY OF LITERATURE REVIEW: Anterior lumbar interbody fusion distracts the height and width of the neural foramen. MATERIALS AND METHODS: Anterior interboody fusion with posterior fixation was performed in twenty-five patients. The sagittal parameters were the height and area of the neural foramen. The fused lumbar segments was imaged in the direct sagittal projections in a CT (SOMATOM Senstaion; SIMENS, Germany) and 1-mm slice thickness before surgery and after solid fusion. Computer digitation was used for the measurements independently by three different observers. Statistical analysis was performed using a Wilcoxon signed test and a paired T-test to determine the correlation between the measurements, and Pearson correlation to determine the level of interobserver and intraobserver agreement. RESULTS: After anterior interbody fusion and posterior fixation, the height and the area of the neural foramen had increased significantly by 15.5+/-14.0%(p.0.001) and 23.2+/-17.7%(p.0.001). There was a significant confidence in interobserver (0.9466~0.9996) and intraobserver(0.8896~0.9991) agreement. CONCLUSIONS: Anterior interbody fusion significantly increased the changes in the dimensions of the neural foramen. Anterior distraction and decompression with anterior interbody fusion increased the area of the neural foramen This study shows that anterior interbody fusion can be used to decompress the neural foramen in the spondylolisthesis.

Anterior Debridement and Strut Graft with Pedicle Screw Fixation for Pyogenic Spondylitis

STUDY DESIGN: A retrospective study. PURPOSE: We evaluated the results of the use of anterior debridement and interbody fusion followed by posterior spinal instrumentation. OVERVIEW OF LITERATURE: An early diagnosis of pyogenic spondylitis is difficult to obtain. The disease can be treated with various surgical methods (such as anterior debridement and bone graft, anterior instrumentation, and posterior instrumentation). METHODS: This study included 20 patients who received anterior debridement and interbody fusion with strut bone graft followed by posterior spinal fusion for pyogenic spondylitis between 1996 and 2005. We analyzed the culture studies, the correction of the kyphotic angle, blood chemistry, the bony union period, and the amount of symptom relief. RESULTS: In terms of clinical symptoms relief, eight patients were grouped as "excellent", eleven patients as "good", and one patient as "fair". The vertebral body cultures were positive in 14 patients showing coagulase (-) streptococcus and S. aureus. The average times for normalization of the erythrocyte sedimentation rate and C-reactive protein level were 3.3 and 1.9 months, respectively. Four months was required for bony union. For complications, meralgia paresthetica was found in two cases. CONCLUSIONS: Due to early ambulation and the correction of the kyphotic angle, anterior interbody fusion with strut bone graft and posterior instrumentation could be another favorable method for the treatment of pyogenic spondyulitis.

Influence of Plate Position on Fusion Time and Clinical Outcomes after Anterior Cervical Interbody Fusion / 대한척추외과학회지

STUDY DESIGN: This was a retrospective study to evaluate anterior cervical interbody fusion with plates. OBJECTIVE: To examine the degree of angulation and translation after an anterior interbody fusion, using anterior plate fixation, upon the fusion rate and clinical outcome. SUMMARY OF LITERATURE REVIEW: Anterior cervical interbody fusion with plate allows immediate rigid internal fixation after decompression and bone grafting. MATERIALS AND METHODS: 65 cases had an anterior interbody fusion on the cervical spine, using an anterior approach and Smith-Robinson's method, between January 1998 and August 2003. Of these, 41 cases, which could be followed up for at least one year, were selected. There were 26 and 15 males and females, respectively, with an average age of 43.5 and mean follow up period of 2.1 years. 15 cases underwent an operation due to dislocation or fracture of the cervical spine due to trauma, and 26 due to cervical diseases. The angulation and translation of the plate was measured by postoperative X-rays. The fusion rate was also determined by the follow up X-rays. The Chi-squared test was used to analyze the data. RESULTS: Bony fusion was obtained in all cases. Two patients developed hoarseness and one showed torticollis, but all had recovered by the follow up. The average angulation of the plate and translation were 6.2 degrees and 3.21mm, respectively, but there was no significant difference of the interbody fusion period due to angulation and translation of the plate or in the improvement of the clinical outcomes. CONCLUSION: In the cases of anterior interbody fusion of the cervical spine, the angulation and translation of the plate had no influence on the fusion time and clinical outcomes. Long term studies and research will be needed to bring about clinically more valuable data.

Long term results of anterior cervical interbody fusion using coral bone spacer for cervical spondylosis / 中华创伤骨科杂志

Objective To evaluate the long term results of coral bone used in anterior cervical interbody fusion. Methods The 180 patients (126 males and 54 females) who had undergone anterior interbody fusion in our hospital were followed up for 6 years. Their long-term imageological data, including changes in interbody height, interbody angle and range of movement, were analyzed and compared. Results In all the cases a solid fusion was achieved between coral reef and vertebra. The fusion was evaluated as successful in all the 180 patients. Conclusion The coral bone spacer provides the same solid fusion as autografting with iliac crest does.