Anterior Spinal Instrumentation Research Articles

Role of Major Spine Surgery Using Kaneda Anterior Instrumentation for Osteoporotic Vertebral Collapse

A retrospective study. To investigate the clinical and radiographic results of spinal reconstruction using Kaneda anterior spinal instrumentation for osteoporotic vertebral collapse. Recent advances in osteoporotic vertebral fracture treatment including kyphoplasty changes the role of major surgery for these pathologies. However, osteoporotic vertebral collapse with neurologic compromise remains requiring surgical decompression and reconstruction. Thirty-one consecutive patients who underwent anterior spinal reconstruction for osteoporotic vertebral collapse with neurologic deficits were reviewed retrospectively. Twenty-six patients had single vertebral collapse and 5 had multiple lesions. They were 10 males and 21 females with mean age of 71 years. Mean follow-up period was 57 months. For anterior column support, iliac bone graft was used in 1 patient, cylindrical titanium cages in 12, and bioactive ceramic spacers in 18 patients. Kaneda anterior instrumentation was used in all the patients. Radiographic and clinical assessments were performed preoperatively and at the final follow-up. All the patients showed neurologic recovery. Visual analog scales (0 to 10) of low back pain and sciatic pain were 5.8 and 4.2 before surgery, and 2.1 and 0.6 at the final follow-up, respectively. Mean kyphosis of operative levels was 31 degrees before surgery, and improved to 13 degrees immediately after surgery and 21 degrees at the final follow-up. Posterior reinforcement was required in 6 patients (19%), who had severe osteoporosis and/or underwent multilevel corpectomies. Solid fusion was achieved in all patients at the final follow-up. The current study demonstrated the advantages of anterior spinal reconstruction in osteoporotic vertebral collapse: (1) safe and reliable decompression could be performed, and (2) 80% of patients were successfully treated with anterior spinal reconstruction alone. However, patients with multilevel corpectomies and/or severe osteoporosis highly required posterior reinforcement.

Long-term Outcomes of Anterior Spinal Fusion With Instrumentation for Thoracolumbar and Lumbar Curves in Adolescent Idiopathic Scoliosis

A retrospective review of the long-term clinical and radiographic outcomes of anterior spinal fusion with instrumentation for thoracolumbar and lumbar curves in adolescent idiopathic scoliosis (AIS). To evaluate a group of patients based on Scoliosis Research Society (SRS)-30 and Oswestry data as well as radiographic and magnetic resonance imaging (MRI) and report the results of long-term follow-up of this surgical treatment for this particular curve pattern in AIS. Anterior spinal fusion with instrumentation has been used for many years in the treatment of thoracolumbar and lumbar curves in AIS. However, the long-term radiographic and functional outcomes of this procedure are not well known. During 1984 to 1995, 31 patients with the diagnosis of AIS underwent anterior spinal instrumentation and fusion for thoracolumbar or lumbar scoliosis at our institution. A retrospective review of this patient group was performed to evaluate patient satisfaction, functional outcome, curve progression, implant failure, and disc degeneration. Radiographs and lumbar MRIs were obtained along with SRS-30 Questionnaire and Oswestry Disability Index data. Eighteen patients were available for review. Average follow-up for this study was 16.97 years. Based on SRS-30 and the Oswestry Disability Index data, most patients had good function scores and acceptable pain levels. Radiographs demonstrated no progression of the thoracolumbar or thoracic curves. Implant failure was identified in 2 patients. Radiographic changes of early degenerative disc disease were identified in most patients but had no correlation with SRS or Oswestry data. These degenerative changes were evident on both radiographs and MRI. The anterior approach in the treatment of thoracolumbar and lumbar curves in AIS offers good long-term functional outcomes for patients. Despite expected degenerative changes, patients scored well on the SRS and Oswestry tests, and were able to pursue careers and family activities.

Surgical Treatment of Main Thoracic Scoliosis with Thoracoscopic Anterior Instrumentation

The surgical outcomes in patients with scoliosis at two years following anterior thoracoscopic spinal instrumentation and fusion have been reported. The purpose of this study was to evaluate the results at five years. A consecutive series of forty-one patients with major thoracic scoliosis treated with anterior thoracoscopic spinal instrumentation was evaluated at regular intervals. Prospectively collected data included patient demographics, radiographic measurements, clinical deformity measures, pulmonary function, an assessment of intervertebral fusion, and the scores on the Scoliosis Research Society (SRS-24) outcomes instrument. Perioperative and postoperative complications were recorded. Patient data for the preoperative, two-year, and five-year postoperative time points were compared. In addition, a univariate analysis compared selected two-year radiographic, pulmonary function, and SRS-24 data of the study cohort and those of the patients lost to follow-up. Twenty-five (61%) of the original forty-one patients had five-year follow-up data and were included in the analysis. Between the two-year and five-year follow-up visits, no significant changes were observed with regard to the average percent correction of the major Cobb angle (56% +/- 11% and 52% +/- 14%, respectively), average total lung capacity as a percent of the predicted value (95% +/- 14% and 91% +/- 10%), and the average total SRS-24 score (4.2 +/- 0.4 and 4.1 +/- 0.7). Radio-graphic evaluation of intervertebral fusion at five years revealed convincing evidence of a fusion with remodeling and trabeculae present at 151 (97%) of the 155 instrumented motion segments. No postoperative infections or clinically relevant neurovascular complications were observed. Rod failure occurred in three patients, and three patients required a surgical revision with posterior spinal instrumentation and fusion. Thoracoscopic anterior instrumentation for main thoracic idiopathic scoliosis results in five-year outcomes comparable with those reported previously for open anterior and posterior techniques. The radiographic findings, pulmonary function, and clinical measures remain stable between the two and five-year follow-up time points. Thoracoscopic instrumentation provides a viable alternative to treat spinal deformity; however, the risks of pseudarthrosis, hardware failure, and surgical revision should be considered along with the advantages of limited muscular dissection and improved scar appearance.

Radiographic Classification of Complications of Instrumentation in Adolescent Idiopathic Scoliosis

In spinal deformity surgery, techniques and implants must be assessed for their safety and efficacy. Regulatory bodies, third-party payors, and patients will increasingly scrutinize treatment methods based on the frequency of adverse events. We therefore developed a classification of adverse hardware-related events using plain radiographic criteria. We analyzed the adverse events in 466 patients surgically treated for adolescent idiopathic scoliosis for a Type 1 (Lenke et al.) curve. We used plain radiographic films to define complications as either serious radiographic adverse events or radiographic adverse events in four technique groups: posterior spinal fusion with hooks and/or hybrid systems, posterior spinal fusion using mostly pedicle screws, open anterior spinal fusion, and thoracoscopic anterior spinal fusion. We defined serious radiographic adverse events as those requiring subsequent surgery. The minimum followup was 2 years. We found a reoperation rate ranging from 4.5% (open anterior spinal fusion) to 8.8% (posterior spinal fusion with hooks); we found no difference in the incidence of serious radiographic adverse events between surgical techniques. Among serious radiographic adverse events, the most common problems were revision for lumbar progression, rod breakage, and proximal screw pullout in the anterior spinal fusions and instrumentation removal for pain and infection in the posterior spinal fusions. We propose a new radiographic system of adverse hardware-related events for patients with Type 1 adolescent idiopathic scoliosis. Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Onset of a Charcot spinal arthropathy at a level lacking surgical arthrodesis in a paraplegic patient with traumatic cord injury

The study design included a case report of Charcot spinal arthropathy treated with posterior and anterior spinal instrumentation. The objective of the study was to report an unusual case of Charcot spinal arthropathy as a late complication of traumatic spinal cord injury in a patient previously treated with a long posterior thoraco-lumbar instrumentation and postero-lateral fusion. A 33-year-old man with T10-T11 complete paraplegia presented with focal low back pain, kyphotic deformity of the lumbar region with L2-L3 fracture-dislocation and hardware failure. Our treatment consisted of a circumferential arthrodesis performed with a combined anterior and posterior approach. Spinal stabilization was achieved and the patient was pain free and able to resume a sitting posture. This report suggests that the development of a Charcot spine arthropathy must always be considered as a late complication of a spinal cord injury. Moreover, we would emphasize the fundamental role of a strict clinical and radiological follow-up in order to detect an early Charcot spine complication.

Delayed-iatrogenic injury of the thoracic aorta by an anterior spinal instrumentation

We present a case of a 15-year-old girl who presented to us with an unusual low back pain. About 7 years ago, this patient had corrective surgery for her idiopathic left thoracolumbar scoliosis. Recent surgery revealed a laceration of the posterior wall of the thoracic aorta by an impending screw thread. This injury was repaired by the vascular surgeons and, subsequently, the patient had full recovery without any complications.

Anterior decompression and spinal instrumentation, for the patient of Th5 metastatic lesion of prostata carcinoma with thoracic myelopathy (a case report)

Anterior decompression and spinal instrumentation, for the patient of Th5 metastatic lesion of prostata carcinoma with thoracic myelopathy (a case report)

Restoration of Thoracic Kyphosis After Operative Treatment of Adolescent Idiopathic Scoliosis

Multicenter analysis of 3 groups of patients who underwent surgical treatment for adolescent idiopathic scoliosis (AIS). OBJECTIVE.: To evaluate 3 surgical approaches to determine the modality that has the greatest influence on improving thoracic kyphosis. AIS is characterized by thoracic hypokyphosis which may be restored to normal to varying degrees with surgery. A multicenter retrospective AIS surgical database was reviewed. Patients with only a structural main thoracic curve (Lenke 1, 2, or 3), and instrumentation of only the main thoracic curve were included. Lateral radiographs were analyzed to determine sagittal plane measurements before surgery, after surgery at 6 to 8 weeks, 1 year, and 2 years. The 3 groups were compared and statistical significance was defined as P < 0.05. Three groups were analyzed: (1) ASF group (n = 135), Anterior spinal fusion and instrumentation, (2) PSF-Hybrid group (n = 86), PSF with proximal hooks, +/- apical wires and distal pedicle screws, and 3) PSF-Hooks group (n = 132), PSF with only hooks. All groups had similar preoperative coronal main thoracic curve magnitudes (ASF: 50.6 degrees , PSF-Hybrid: 49.1 degrees , PSF-Hooks: 52.0 degrees ) and thoracic kyphosis (ASF: 23.7 degrees , PSF-Hybrid: 19.3 degrees , PSF-Hooks: 21.9 degrees ). After surgery, the T5-T12 kyphosis was greater in the ASF group (25.1 degrees ) compared with PSF-Hooks (19.0 degrees ) and PSF-Hybrid (18.5 degrees (P < 0.05). At 1 year, thoracic kyphosis (T5-T12) remained greater in the ASF group (28.8 degrees ) compared with PSF-Hooks (22.6 degrees ) and PSF-Hybrid (20.2 degrees ) (P < 0.05), and was also greater at 2 years (29.9 degrees vs. 23.8.8 degrees and 19.7 degrees ) (P < 0.05). Kyphosis at the thoracolumbar junction was not seen in the PSF-Hybrid group. Lumbar lordosis increased only in the ASF group in response to the increase in thoracic kyphosis. ASFI is the best method to restore thoracic kyphosis when compared with posterior approaches using only hooks or a hybrid construct in the treatment of thoracic adolescent idiopathic scoliosis.

Accuracy of Thoracic Vertebral Screw Insertion in Adolescent Idiopathic Scoliosis

A cross-sectional study with axial computed tomography (CT) to compare the accuracy of vertebral screw insertion in the thoracic spine for adolescent idiopathic scoliosis (AIS) between the thoracoscopic and the mini-open thoracotomy approach. To evaluate the safety of vertebral screw placement in anterior instrumentation for thoracic AIS. Thoracoscopic anterior instrumentation has been used with good results for AIS. It is technically demanding especially for the insertion of vertebral screws. The important issue of whether the screws inserted thoracoscopically is as accurate and safe as those inserted through thoracotomy approach has not been well studied. Thirty-one patients with thoracic AIS receiving thoracoscopic or mini-open thoracotomy anterior instrumentation were included in this study. They were divided into Group A and B, respectively. Postoperative sequential CT scanning on the thoracic vertebral screws was carried out. The relative position between screws and the spinal canal, the aorta, and the bicortical purchase were analyzed with CT images. The percentage of screws in good position was defined and further analyzed. Seventy-three and 162 thoracic vertebral screws were inserted in 10 patients in Group A and 21 patients in Group B, respectively. Eighty-nine percent of screw tips in Group A and 80.2% in Group B were distant from the aorta, 89.0% and 87.0% of screws achieved bicortical purchase in Group A and B, respectively. No significant difference was found in all thoracic levels including the upper thoracic, periapical, or lower thoracic vertebrae. Seventy-four percent and 66.7% of screws were in good positions in Group A and B, respectively and there was no statistically significant difference between the 2 groups. The vertebral screws inserted through thoracoscopic approach were as accurate as those inserted through a mini-open thoracotomy approach. The accuracy could be enhanced by using screws with smaller increments, with special attention to the possible migration of aorta with anterior spinal instrumentation.

Surgical Treatment of Main Thoracic Scoliosis with Thoracoscopic Anterior Instrumentation

The surgical outcomes in patients with scoliosis at two years following anterior thoracoscopic spinal instrumentation and fusion have been reported. The purpose of this study was to evaluate the results at five years. A consecutive series of forty-one patients with major thoracic scoliosis treated with anterior thoracoscopic spinal instrumentation was evaluated at regular intervals. Prospectively collected data included patient demographics, radiographic measurements, clinical deformity measures, pulmonary function, an assessment of intervertebral fusion, and the scores on the Scoliosis Research Society (SRS-24) outcomes instrument. Perioperative and postoperative complications were recorded. Patient data for the preoperative, two-year, and five-year postoperative time points were compared. In addition, a univariate analysis compared selected two-year radiographic, pulmonary function, and SRS-24 data of the study cohort and those of the patients lost to follow-up. Twenty-five (61%) of the original forty-one patients had five-year follow-up data and were included in the analysis. Between the two-year and five-year follow-up visits, no significant changes were observed with regard to the average percent correction of the major Cobb angle (56% +/- 11% and 52% +/- 14%, respectively), average total lung capacity as a percent of the predicted value (95% +/- 14% and 91% +/- 10%), and the average total SRS-24 score (4.2 +/- 0.4 and 4.1 +/- 0.7). Radiographic evaluation of intervertebral fusion at five years revealed convincing evidence of a fusion with remodeling and trabeculae present at 151 (97%) of the 155 instrumented motion segments. No postoperative infections or clinically relevant neurovascular complications were observed. Rod failure occurred in three patients, and three patients required a surgical revision with posterior spinal instrumentation and fusion. Thoracoscopic anterior instrumentation for main thoracic idiopathic scoliosis results in five-year outcomes comparable with those reported previously for open anterior and posterior techniques. The radiographic findings, pulmonary function, and clinical measures remain stable between the two and five-year follow-up time points. Thoracoscopic instrumentation provides a viable alternative to treat spinal deformity; however, the risks of pseudarthrosis, hardware failure, and surgical revision should be considered along with the advantages of limited muscular dissection and improved scar appearance. Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

Comparison Between 4.0-mm Stainless Steel and 4.75-mm Titanium Alloy Single-Rod Spinal Instrumentation for Anterior Thoracoscopic Scoliosis Surgery

Retrospective review of a consecutive, single surgeon case series. To compare minimum 2-year postoperative outcomes between 4.0-mm stainless steel and 4.75-mm titanium alloy single-rod anterior thoracoscopic instrumentation for the treatment of thoracic idiopathic scoliosis. Advances in anterior thoracoscopic spinal instrumentation for scoliosis have attempted to mitigate the postoperative complications of rod failure, pseudarthrosis, and deformity progression. Biomechanical data suggest that the 4.75-mm titanium construct has a lower risk of fatigue failure compared to the 4.0-mm stainless steel construct. Sixty-four consecutive anterior thoracoscopic spinal instrumentation cases in patients with thoracic scoliosis performed by a single surgeon and with minimum 2-year follow-up were retrospectively reviewed. The first 34 cases used a 4.0-mm stainless steel (SS) construct, whereas the subsequent 30 cases used a 4.75-mm titanium (Ti) alloy instrumentation system. The first 10 SS cases and the first 5 Ti cases were excluded from the statistical comparison to account for a potential learning curve effect. A multivariate analysis of variance (P < 0.05) was used to compare radiographic, perioperative, and postoperative complication data between patients surgically treated with the 2 different instrumentation systems. Patients in the SS group (n = 24) underwent surgery from 2000 to 2001, whereas patients in the Ti group (n = 25) underwent surgery from 2002 to 2004. The mean age at surgery, gender ratio, length of hospitalization, estimated blood loss, and operative time were not statistically different between the 2 patient groups (P > 0.13). The average follow-up in the SS group was, however, significantly longer than in the Ti group (4.0 +/- 1.4 years vs. 2.3 +/- 1.0 years; P = 0.001). Preop main thoracic Cobb angles were similar between the 2 groups (P = 0.62); however, the 2-year main thoracic Cobb was significantly smaller (P = 0.03) and the 2-year percent correction was significantly greater in the Ti group (P = 0.03). Five patients (21%) in the SS group had a pseudarthrosis, 3 (13%) experienced rod failure, and 2 (8%) required a revision posterior spinal fusion. In the Ti group, 2 patients (8%) had a pseudarthrosis, and no patient experienced rod failure or required a revision procedure. Although the average follow-up in the Ti group was significantly shorter than in the SS group, the 4.75-mm titanium alloy construct resulted in improved maintenance of deformity correction at 2-years postop and a lower incidence of instrumentation-related complications (pseudarthrosis, rod breakage, and surgical revisions) compared to the 4.0-mm stainless steel construct. Improved outcomes with the titanium alloy construct are likely because of the mechanical properties of the implant, refined patient selection criteria, and greater surgical experience gained with time.

Return of Shoulder Girdle Function After Anterior Versus Posterior Adolescent Idiopathic Scoliosis Surgery

Multicenter, prospective, cohort study. To compare minimum 2-year postoperative shoulder function after 3 different surgical approaches for the treatment of primary thoracic curves in patients with adolescent idiopathic scoliosis (AIS). Thoracic spinal instrumentation and fusion can be performed via posterior (PSF), open anterior (OASF), or thoracoscopic anterior (TASF) techniques. Although the morbidity of these 3 surgical approaches is beginning to be understood, no reports have been published comparing 2-year postoperative shoulder strength and range of motion. AIS patients who underwent selective fusion of primary thoracic curves were studied. Right-sided shoulder strength (flexion, abduction) and range of motion (flexion, extension, abduction) measurements were collected prospectively at selected intervals. An arbitrary threshold (80% of preoperative value) was defined as postoperative return of normal shoulder function. Univariate analysis of variance (P < 0.05) was used to compare differences in shoulder function for the 3 approaches at each postoperative time-point. Ninety-two patients with minimum 2-year postoperative shoulder function data were included in this study (24 PSF, 32 OASF, and 36 TASF). On average, patients who had an OASF failed to reach the 80% threshold for right shoulder forward flexion and abduction strength until 1-year and 6-months after surgery, respectively; whereas patients that had a TASF or PSF returned to normal shoulder strength by the 3-month follow-up visit. With regards to ROM, patients in all 3 groups surpassed the 80% preoperative threshold for right shoulder active forward flexion and extension by the 6-week visit, with no clinically significant differences between the groups. However, for active abduction range of motion, patients that had an OASF required 3-months to regain 80% of their preoperative motion, compared to 6-weeks for patients in both the TASF and PSF groups. Approach-related differences in shoulder morbidity do exist in the treatment of primary thoracic curves in AIS. Specifically, OASF imparts a significantly greater magnitude and duration of postoperative shoulder dysfunction than do the TASF or PSF approaches. Nonetheless, these negative effects are transient as shoulder function in those patients treated via an open thoracotomy normalized by the 1-year postoperative time-point at the latest. Accordingly, viewed in isolation, shoulder morbidity should not deter surgeons from using an open anterior approach in the surgical treatment of AIS.

The changes of relative position of the thoracic aorta after anterior or posterior instrumentation of type I Lenke curve in adolescent idiopathic thoracic scoliosis

The risk of impingement of the aorta associated with thoracic vertebral screw or pedicle screw instrumentation in the treatment of thoracic scoliosis has been an important concern. To understand this phenomenon more systematically, the relative position of the aorta with reference to the thoracic vertebrae in right thoracic adolescent idiopathic scoliosis (AIS) following anterior and posterior spinal instrumentation was analyzed in detail quantitatively; 34 patients underwent anterior (n = 14) or posterior (n = 20) spinal instrumentation were recruited in the present study. The relative position of the thoracic aorta, vertebral rotation, apical vertebral translation and thoracic kyphosis were measured from pre- and post-operative CT images from T5 to T12. The aorta was found to shift antero-medially in the anterior instrumentation group but not in the posterior spinal instrumentation group. It is likely that the disc removal, soft tissue release and spontaneous vertebral derotation of the scoliosis could account for the antero-medial shifting of the aorta. By the shifting, the space for contralateral screw penetration was reduced.

The Awl-Staple Versus Guidewire Method for Placing Vertebral Screws in Thoracoscopic Anterior Spinal Fusion and Instrumentation for Adolescent Idiopathic Scoliosis

A retrospective chart and radiograph review in a consecutive series of patients at a single institution. To compare 2 methods of placing vertebral body screws in thoracoscopic anterior spinal fusion and instrumentation with respect to radiographic, clinical, and perioperative variables. Placing vertebral body screws in thoracoscopic anterior spinal fusion and instrumentation for adolescent idiopathic scoliosis can be performed using 2 methods: the awl/staple technique and the guidewire method. There are no current studies that have compared both of these techniques. Two groups of patients were analyzed depending on the method of screw placement: The AS group (n=15) used the awl/staple method and the GW group (n=27) used the guidewire method. Surgical times and estimated blood loss were obtained from the medical record. Fluoroscopy times were obtained from the radiology technician. Preoperative posteroanterior standing, bending, and immediate postoperative radiographs were examined to determine the primary curve magnitude, postoperative curve correction, curve flexibility, and the Lenke classification. The AS group had significantly less fluoroscopy times (156.6+/-71.4 vs. 328.4+/-171.6 s) and operative times (416.1+/-65.4 vs. 505.6+/-61.8 min) compared with the GW group (P<0.05). When calculating the duration per fusion level, the AS group was also shorter for fluoroscopy times (27.1+/-13.2 vs. 49.3+/-24.5 s/level) (P<0.05) and surgical times (72.0+/-15.2 vs. 76.9+/-9.8 min/level) (P=0.10). There was a trend toward a lower incidence of screw plow or pullout (0.0% vs. 14.8%) for the AS group (P=0.157). The awl/staple technique is the preferred technique for placing vertebral body screws when performing thoracoscopic anterior spinal fusion/instrumentation because it has shorter fluoroscopy times, surgical times, and a lower incidence of screw plow/pullout than the traditional guidewire method.

Posterior midline approach for single-stage en bloc resection and circumferential spinal stabilization for locally advanced Pancoast tumors

The treatment of Pancoast (superior sulcus) tumors that extensively invade the vertebral column remains controversial. Different surgical approaches involving multistage resection techniques have been previously described for superior sulcus tumors that invade the chest wall and spinal column. Typically a posterior approach to stabilize the spine is followed by a second-stage thoracotomy (posterolateral or trap door) for definitive en bloc resection of stage T4 Pancoast tumors. The authors report and elaborate on a surgical technique successfully used for an en bloc resection as well as spinal stabilization through a single-stage posterior approach without any added morbidity. Two patients with histologically proven Pancoast tumors were treated by single-stage resection and stabilization through a posterior approach at the H. Lee Moffitt Cancer Center. A wedge lung resection or lobectomy was performed by the chest surgeon utilizing the chest wall defect. Placement of an anterior cage (in one case) and posterior cervicothoracic spinal instrumentation (in both cases) was performed during the same operation. Average blood loss was 675 ml and surgical time was 7 hours. The median hospital stay was 9 days (range 7-11 days). Both patients did well postoperatively and were free of recurrence at the 2-year follow-up. Radical resection of Pancoast tumors including lobectomy, chest wall resection, costotransversectomy, and partial or complete vertebrectomy with simultaneous instrumentation for spinal stabilization can be performed through a posterior single-stage approach.

Prospective Pulmonary Function Comparison of Anterior Spinal Fusion in Adolescent Idiopathic Scoliosis

Prospective clinical study of a retrospective database. To compare the prospective pulmonary function changes following anterior spinal instrumentation and fusion through an open thoracotomy with the same procedure through a thoracoabdominal approach at 2 years follow-up. Open anterior spinal instrumentation and fusion for adolescent idiopathic scoliosis (AIS) has been known to decrease pulmonary function after surgery. However, the differential effect of an open thoracotomy versus thoracoabdominal approach on pulmonary function in AIS is unknown. Sixty-four AIS patients who underwent an anterior spinal instrumentation and fusion through an open thoracotomy (TC group) for a major main thoracic scoliosis were compared with 55 patients who underwent the same procedure through a thoracoabdominal approach (TA group) for a major thoracolumbar/lumbar (TL/L) scoliosis using pulmonary function tests assessing forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) before surgery and 2 years after surgery. The TC group was divided into 2 groups, TC group with thoracoplasty (1-5 ribs, n = 35) and TC group without thoracoplasty (n = 29). Preoperative and 2-year postoperative absolute FVC in the TC group averaged 3.05L and 2.74L, respectively (0.31L decrease, P < 0.0001) versus 3.27L and 3.21L, respectively (0.06L decrease, P = 0.15) in the TA group. The TC group demonstrated a significantly larger decrease in absolute FVC at 2 years postoperative (P < 0.0001). Preoperative and 2-year postoperative absolute FEV1 in the TC group averaged 2.56L and 2.35L, respectively (0.21L decrease, P < 0.0001) versus 2.82L and 2.81L, respectively (0.02L decrease, P = 0.67) in the TA group. The TC group demonstrated a significantly larger decrease in absolute FEV1 at 2 years postoperative (P = 0.001). TC patients with thoracoplasty (n = 35) demonstrated a similar average decrease (0.34L) of absolute FVC at 2 years postoperative compared with those without thoracoplasty (0.26L, P = 0.49) and a similar average decrease of absolute FEV1 at 2 years postoperative (0.23L vs. 0.19L without thoracoplasty, P = 0.76). An open thoracotomy approach for treating a main thoracic curve demonstrated a significant decrease in the absolute pulmonary function tests values at 2 years postoperative while the thoracoabdominal approach for treating a TL/L curve did not.

Anterior Arthrodesis With Instrumentation for Thoracolumbar Scoliosis

A retrospective review was performed of adult and adolescent patients who underwent anterior spinal fusion for thoracolumbar idiopathic scoliosis; radiographic and clinical outcomes were compared. The objective of this study was to compare the efficacy of anterior instrumentation to treat thoracolumbar scoliosis in adults and adolescents by evaluating radiographic and clinical outcomes. Anterior spinal arthrodesis is an effective treatment for idiopathic scoliosis. Deformity characteristics and clinical outcomes of adults versus adolescents have not been compared. A retrospective review of patients undergoing anterior fusion for thoracolumbar scoliosis was performed. Clinical outcomes were assessed using SRS-22. Preoperative and postoperative long films were evaluated independently. Flexibility, curve correction, and clinical outcomes were compared between adult and adolescents. Fifteen adults and 15 adolescents who underwent anterior spinal fusion and instrumentation were evaluated. Mean follow-up was 47 and 46 months, respectively. Flexibility of the major curve in adults (63%) was less than in adolescents (79%) (P < 0.05). Mean preoperative, major curve Cobb angles were 51 degrees and 49 degrees for adults and adolescents, respectively. Mean postoperative Cobb angles improved less for adults (17 degrees ) than for adolescents (10 degrees ) (P < 0.05). The SRS-22 questionnaire revealed no statistical difference between populations. Anterior spinal fusion is an option for both adults and adolescents with flexible, moderate thoracolumbar/lumbar curves. Flexibility significantly decreased with increased age and curve magnitude. This significantly affected curve correction. Adult patients may develop early degeneration at primary curve and compensatory curves. Careful patient selection is critical with this technique.

Complete recovery of acute paraplegia due to pyogenic thoracic spondylodiscitis with an epidural abscess

Pyogenic spondylodiscitis associated with epidural abscess is a rare but serious problem in spinal surgery, because it may cause a severe morbidity or mortality, if the diagnosis is established late and the treatment is inadequate. A case of pyogenic thoracic spondylodiscitis associated with epidural abscess whose symptoms progressed over two months from back pain to acute paraplegia was presented. Magnetic resonance imaging of the spine suggested the presence of T9-10 spondylodiscitis with partial destruction of the T9 and T10 vertebral bodies and concomitant epidural abscess. Treatment consisting of surgical debridement of infected vertebrae and disc material, fusion and anterior spinal instrumentation was performed. Microbiological culture of the material revealed infection with Staphylococcus aureus and after 3 months of antibiotic treatment, recovery was almost complete. Based on a thorough review of the literature and the case presented in this report, it is concluded that accurate and prompt diagnosis requires high index of suspicion followed by a combination of adequate surgical and conservative treatment prevents severe morbidity in cases of nonspecific pyogenic spondylodiscitis associated with epidural abscess.

A long-term follow-up study of anterior tibial allografting and instrumentation in the management of thoracolumbar tuberculous spondylitis

The purpose of this study was to determine the efficacy of anterior instrumentation following radical debridement and tibial allografting and its long-term progression in patients with multilevel spinal tuberculosis. This prospective observational study was undertaken to analyze 22 patients with multilevel spinal tuberculosis (Pott disease) who underwent anterior radical debridement, decompression, and fusion using anterior spinal instrumentation and tibial allograft replacement between 1999 and 2001. Clinical outcomes were assessed using the American Spinal Injury Association (ASIA) Impairment Scale and a visual analog scale (VAS). Preoperative and postoperative plain radiographs were obtained, and the focal kyphotic angle of the surgically treated spinal segments and the overall sagittal and coronal contours of the thoracic and lumbar spine were evaluated in all patients. The mean follow-up time was 84 months (range 36-96 months). All patients demonstrated clinical healing of the tuberculosis infection. All patients showed evidence of successful bone fusion. The mean late postoperative kyphosis correction was 74% (range 63-91%). On average, 2 degrees (range 0-5 degrees ) of loss of correction was noted in the local kyphotic angle postoperatively in late follow-up findings. Evaluation of the surgical effect on sagittal global contours showed a significant correction rate in thoracic, thoracolumbar, and lumbar regions. The mean late postoperative coronal plane alignment correction was 99%. The ASIA Impairment Scale scores demonstrated significant improvement in late follow-up results in our series. Surgical decompression also resulted in a dramatic reduction of overall pain in all patients (late postoperative VAS score 1.61 +/- 0.81). Anterior tibial allografting and instrumentation provide correction of the curvature, prevention of further deformation, improvement of sagittal and coronal balance, and restoration of neurological function in patients with spinal tuberculosis.

Anterior Interbody Grafting and Instrumentation for Advanced Spondylodiscitis

To evaluate the surgical outcomes of ventral interbody grafting and anterior or posterior spinal instrumentation for the treatment of advanced spondylodiscitis in patients who had failed medical management. A total of 28 patients were evaluated for associated medical illness, detected pathogen, level of involved spine, and perioperative complications. Radiological evaluation including the rate of bony union, segmental Cobb angle, graft- and instrumentation-related complications, and clinical outcomes by mean Frankel scale and VAS score were performed. There are 14 pyogenic spondylodiscitis, 6 postoperative spondylodiscitis, and 8 tuberculous spondylodiscitis. There were 21 males and 7 females. Mean age was 51 years, with a range from 18 to 77. Mean follow-up period was 10.9 months. Associated medical illnesses were 6 diabetes, 3 pulmonary tuberculosis, and 4 chronic liver diseases. Staphylococcus was the most common pathogen isolated (25%), and Mycobacterium tuberculosis was found in 18% of the patients. Operative approaches, either anterior or posterior spinal instrumentation, were done simultaneously or delayed after anterior aggressive debridement, neural decompression, and structural interbody bone grafting. All patients with neurological deficits improved after operation, except only one who died from aggravation as military tuberculosis. Mean Frankel scale was changed from 3.78+/-0.78 preoperatively to 4.78+/-0.35 at final follow up and mean VAS score was improved from 7.43+/-0.54 to 2.07+/-1.12. Solid bone fusion was obtained in all patients except only one patient who died. There was no need for prolongation of duration of antibiotics and no evidence of secondary infection owing to spinal instrumentations. According to these results, debridement and anterior column reconstruction with ventral interbody grafting and instrumentation is effective and safe in patients who had failed medical management and neurological deficits in advanced spondylodiscitis.