Pedicle subtraction osteotomy in the thoracic spine and thoracolumbar junction: a retrospective series of 28 cases

Purpose

Pedicle subtraction osteotomy is a well-described surgical technique for treatment of kyphotic deformity in the spine. It is not widely used for treatment of thoracic kyphosis. We present the first documented series of 28 patients who underwent this procedure in 3 international centers. These patients presented with severe deformity with a wide range of aetiologies.

Indications

Kyphosis larger than 70 degrees, which is demonstrably rigid based on dynamic imaging.

Materials and methods

28 patients underwent surgery following pre-op neurological and radiographic assessment to fully assess the deformity. A triangular osteotomy was carried out using intraoperative navigation techniques. The patients were assessed post-operatively again with clinical and radiographic parameters at regular follow-up.

Results

The mean ODI score after surgery was 24.7 (16–42) while the pre-op was 53.4 (38–76). Mean thoracic kyphosis was improved from 64.2° (±20.1°) to 41.1° (±17.4°) resulting in a mean sagittal correction of 23.1°. Mean segmental correction at the PSO for all 28 cases was 17.8° (±8.1°). Stratified by region we found different values for the PSO correction: between T1 and T5 (6 cases) it was 17.5° (±5.4°) and between T6 and T9 (4 cases) 18.2° (±4.7°) and between T10 and L1 (18 cases) 26.2° (±5.2°). FBI index was 22.3° pre-op and improved to 7.8° post-op. Calculations were performed with Microsoft excel (2011 Microsoft, Redmond, WA).

Conclusions

Global sagittal balance was statistically improved in this series as demonstrated by FBI and C7 SVA correction.

     

经椎弓根截骨术治疗胸腰椎后凸畸形

目的评估经椎弓根截骨术矫正胸腰椎后凸畸形的临床疗效和安全性。方法2001年3月~2007年4月,15例胸腰椎后凸畸形患者进行经椎弓根截骨矫形术。其中强直性脊柱炎8例,陈旧性胸腰椎骨折7例。对所有患者进行随访,内容包括矫正情况、腰痛和Oswestry功能评分的变化。结果平均随访时间为25个月。平均手术时间为230min,术中平均出血量为1780ml。术前后凸Cobb角平均为47.2°,术后为18.0°,平均矫正角度32.3°,融合率80%。术前患者腰痛VAS评分平均为7.4分,术后3.7分。术前ODI平均为58.9%,术后为30.0%。患者主观满意率93.3%。无术中和术后并发症。结论经椎弓根截骨术对于矫正胸腰椎后凸畸形有效而安全,应该根据患者的实际情况选择合适的截骨部位。     

Pedicle subtraction osteotomy for rigid kyphosis of the dorsolumbar spine

Method  

Pedicle subtraction osteotomy is one of the well established and popular techniques for kyphosis correction. 52 patients with dorsolumbar kyphosis followed up for a minimum period of 2 years after pedicle subtraction osteotomy were assessed prospectively for clinico-radiological and functional outcomes. Unacceptable cosmesis and severe back pain were the chief complaints preoperatively.     

Pedicle subtraction osteotomy through pseudarthrosis to correct thoracolumbar kyphotic deformity in advanced ankylosing spondylitis

Introduction  

Surgical treatment is mandatory for spinal pseudarthrosis in advanced ankylosing spondylitis (AS) patients with painful sagittal deformity and/or neurological deficits. However, the most effective and safe surgical procedure for AS-related symptomatic thoracolumbar pseudarthrosis is still controversial. The purpose of this study is to explore the outcomes of pedicle subtraction osteotomy (PSO) at the level of pseudarthrotic lesion combined with supplemental anterior fusion for patients suffering from kyphotic pseudarthrosis in AS.     

经后路改良楔形截骨治疗创伤后胸腰椎骨折后凸畸形

目的 观察后路经椎弓根椎体椎间隙楔形截骨治疗创伤后胸腰椎骨折后凸畸形的临床疗效。方法 自2011-01-2014-01共22例创伤后胸腰椎骨折脊柱后凸畸形患者采用改良PSO截骨矫形技术治疗,所有患者均有严重的胸腰区慢性疼痛,VAS评分≥7分,无神经功能障碍。结果 1例术中发生硬膜撕裂,无神经血管损伤。在Cobb角,VAS评分和ODI评分方面,术后两次测量结果较之术前,差异均有统计学差异（P〈0.05）,所有病例截骨面均骨性愈合。结论 经椎弓根椎体椎间隙楔形截骨矫正创伤后胸腰椎骨折后凸畸形是一种有效的手术方法,截骨面融合率高,并发症发生率低。     

Pedicle morphology of the immature thoracolumbar spine

STUDY DESIGN: Human vertebral morphologic data were compiled from anatomic skeletal collections from three museums. OBJECTIVES: To quantify the morphometric characteristics of the pedicles of the immature thoracolumbar spine. SUMMARY OF BACKGROUND DATA: Little is known of pedicle morphology of the immature spine as related to pedicle screw fixation. METHODS: A total of 75 anatomic skeletal specimens were acquired from C1 to L5 in the age range of 3 to 19 years. The data were collected and analyzed using a computerized video analysis system. Each vertebral pedicle was measured in the axial and sagittal planes. The measurements included the minimum pedicle width, the pedicle angle, the distance to anterior cortex, and anteroposterior and interpedicular spinal canal diameters. RESULTS: Wide variation in pedicle morphology between specimens at each vertebral level was found in the young population. In general, compared with the average adult data, a younger spine demonstrated a near uniform reduction in the linear pedicle dimensions at each vertebral level. Pedicles from the lower lumbar vertebrae attained dimensions acceptable for standard screw sizes at an earlier age than in the thoracic vertebrae. CONCLUSIONS: The data in this study indicates that pedicle screws may be used in the adolescent spine. However, care should taken to accurately ascertain pedicle size before surgery so that improper use of screws can be avoided. Growth of the pedicles in relation to the spinal canal indicates that the increase in pedicle size is lateral to the spinal canal.     

保留椎弓根下壁的椎体截骨术治疗陈旧性胸腰椎骨折后凸畸形

目的 评估经后路保留椎弓根下壁椎体截骨术治疗陈旧性胸腰椎骨折后凸畸形的手术方式及其临床疗效.方法 37例陈旧性胸腰椎骨折后凸畸形患者经后路行保留椎弓根下壁椎体截骨术,平均随访38.6个月.术前、术后3个月分别测量胸腰椎后凸Cobb角、截骨区前缘和后缘的高度以及填写视觉模拟疼痛量表（visual analog scale,VAS）.末次随访时测量胸腰椎后凸Cobb角.结果 术前Cobb角为41.6°±7.8°,术后3个月Cobb角为7.8°±4.3°,与术前相比差异有显著统计学意义（P＜0.05）;末次随访时Cobb角为8.6°±4.1°,较术后3个月无明显丢失（P＞0.05）.截骨区前缘高度增加（2.7±0.8）mm.截骨区后缘高度压缩（7.2±3.1）mm.术前、术后3月VAS评分分别为（7.1±2.9）分和（2.5±1.3）分,较术前明显改善（P＜0.05）.结论 保留椎弓根下壁椎体截骨术能够安全有效地矫正胸腰椎后凸畸形,完整地保留了伤椎峡部及下关节突,保持了伤椎与下位脊椎的连续性,减少了截骨区脊椎矢状面的移位,同时也保留了神经根通道的上壁,从而减少了神经根的损伤.     

Corner osteotomy: a modified pedicle subtraction osteotomy for increased sagittal correction in the lumbar spine

Introduction

Sagittal imbalance is a spine deformity with multifactorial etiology, associated with severe low back pain and gait disturbance that worsen deeply patients’ quality of life. The amount of correction achievable through PSO is limited by the height of the resection of the posterior wall, causing a ceiling of segmental correction of 30–35°. The aim of this study is to describe and preliminarily evaluate the results of an alternative technique, corner osteotomy (CO), that can increase the amount of correction.

Materials and methods

From March 2012, every patient examined in our Division, diagnosed with sagittal imbalance to be treated with PSO, underwent CO and fusion. This technique consists in removing the posterior vertebral arch, the pedicle and the posterior–superior corner of the vertebral body; the inferior endplate of the vertebra above is prepared and the superior adjacent disc removed to obtain, when closing the osteotomy, a direct interbody fusion. Ten patients undergoing CO were compared with 20 patients undergoing PSO regarding spinopelvic parameters, operative variables, complications and degree of correction.

Results

Patients undergoing CO obtained higher lordotic angle at the osteotomy than patients undergoing PSO (36.6° ± 8.2° vs 16.5° ± 9.5°, p < 0.001) and had lower postoperative PT and SVA and higher average increase in lordosis. Complications were similar between groups. A trend toward longer surgical time, greater bleeding and higher transfusion rate was observed in the CO group, though this finding could be related to higher complexity of cases or incidence of associated anterior approach.

Discussion and conclusions

Corner osteotomy technique was more effective than the PSO in increasing segmental and lumbar lordosis with modest increase in blood loss and similar complication rate. The CO technique, in addition, proved a good reproducibility. Further studies with larger populations should confirm these preliminary results.

     

Corner osteotomy: a modified pedicle subtraction osteotomy for increased sagittal correction in the lumbar spine

Introduction

Sagittal imbalance is a spine deformity with multifactorial etiology, associated with severe low back pain and gait disturbance that worsen deeply patients’ quality of life. The amount of correction achievable through PSO is limited by the height of the resection of the posterior wall, causing a ceiling of segmental correction of 30–35°. The aim of this study is to describe and preliminarily evaluate the results of an alternative technique, corner osteotomy (CO), that can increase the amount of correction.

Materials and methods

From March 2012, every patient examined in our Division, diagnosed with sagittal imbalance to be treated with PSO, underwent CO and fusion. This technique consists in removing the posterior vertebral arch, the pedicle and the posterior–superior corner of the vertebral body; the inferior endplate of the vertebra above is prepared and the superior adjacent disc removed to obtain, when closing the osteotomy, a direct interbody fusion. Ten patients undergoing CO were compared with 20 patients undergoing PSO regarding spinopelvic parameters, operative variables, complications and degree of correction.

Results

Patients undergoing CO obtained higher lordotic angle at the osteotomy than patients undergoing PSO (36.6° ± 8.2° vs 16.5° ± 9.5°, p < 0.001) and had lower postoperative PT and SVA and higher average increase in lordosis. Complications were similar between groups. A trend toward longer surgical time, greater bleeding and higher transfusion rate was observed in the CO group, though this finding could be related to higher complexity of cases or incidence of associated anterior approach.

Discussion and conclusions

Corner osteotomy technique was more effective than the PSO in increasing segmental and lumbar lordosis with modest increase in blood loss and similar complication rate. The CO technique, in addition, proved a good reproducibility. Further studies with larger populations should confirm these preliminary results.

     

Injuries of the upper cervical spine: A series of 28 cases

Background:

There are very few published reports of upper cervical spine injuries from our country and there is a heavy bias towards operative treatment of these injuries. We present below our experience of upper cervical injuries over the last four years.

Materials and Methods:

Twenty eight patients (20 males, 8 females) with upper cervical spine injury (including Occiput, Atlas and Axis) were treated and were followed-up for an average of 11.2 months. The data was analyzed retrospectively with regards to the location and type of injury, the treatment offered (conservative or operative) as well as the final clinical and radiological outcome.

Results:

The clinico-radiological outcome of treatment of these injuries is mostly very good with few complications. Other than a single case of mortality due to associated head injury there were no major complications.

Conclusion:

Management of these patients needs a proper evaluation to arrive at the type of injury and prompt conservative or operative treatment. Treatment is usually safe and effective with good clinical and radiological outcome.     

Single-stage transpedicular decompression and posterior instrumentation in treatment of thoracic and thoracolumbar spinal tuberculosis: a retrospective case series

OBJECTIVE: We compare the surgical results of single-stage posterior surgical procedure performed at a single institute with those of anterior procedure, and propose single-stage posterior surgical approach, laminectomy and posterior decompression with transpedicular instrumentation as an alternative operative method for thoracic and thoracolumbar spinal tuberculosis. METHODS: From January 2001 to December 2004, 10 patients (group 1) who had less bone destruction or poor medical condition were treated with posterior decompression and transpedicular instrumentation that was supplemented with posterolateral bone fusion and chemotherapy. Seven patients (group 2) who had greater bone destruction were treated with anterior decompression, bone fusion, and anterior instrumentation. Except one case who expired, all patients were followed up for average 18 months (6 mo to 3.5 y). RESULTS: Spinal tuberculosis was completely cured and the grafted bones were fused in all 16 patients. The visual analog scale and Frankel grade improved in all cases. There was no persistence or recurrence of infection possibly related to the instrumentation. There were no differences in the radiological results in both groups. The kyphosis was significantly corrected after surgical management. However, the loss of correction also occurred considerably in both groups. CONCLUSIONS: The posterior decompression with transpedicular instrumentation can be an alternative treatment method of less-involved spinal tuberculosis especially for patients in early phase of bone destruction or ones with mild kyphosis.     

Endoscopic surgery on the thoracolumbar junction of the spine

It is a measurement of Cobb’s angles between adolescent (AIS) and juvenile (JIS) idiopathic scoliosis who had stable curves (variation <5 degrees) in more than three visits. Main objective of this paper is to measure inter- and intra-observer reliability of measurements between AIS and JIS who had stable curves in regular follow-up. Twenty-nine JIS and 44 AIS patients who had stable curves without bracing were identified using PACS system. Two observers independently measured Cobb’s angle twice on first, during follow-up and final radiogram using computer-based digital radiogram. Both observers were given pre-decided level of upper and lower end plates. Inter- and intra-observer reliability of the measurement was calculated using Pearson correlation-coefficient test between JIS and AIS group. There was no significant difference in Cobb’s angle in all measurements by both observers either in JIS (p = 0.756, range 0.706–0.815; ANOVA) or AIS (p = 0.871, range 0.795–0.929; ANOVA) group which suggested that there is no significant difference in Cobb’s angle in repeated measurements. Intra-observer reliability for JIS (r = 0.600, range 0.521–0.751; Pearson test) was less than AIS (r = 0.969, range 0.943–0.984; Pearson test); and similarly, inter-observer reliability for JIS (r = 0.547, Pearson test) was also less than AIS (r = 0.961, Pearson test) which indicates that Cobb’s angle measurement is less reliable in patients who have juvenile idiopathic scoliosis. Using the identical condition for measurements in both the groups, we could find only one reason for less reliability in JIS group and that is poor demarcation of the vertebral end-plates in this group. This poor inter- and intra-observer reliability in JIS due to ill-defined endplates can be reduced by measuring all previous curves along with latest curves at the same time during the follow-up of patients with JIS to decide about the progression of curves and treatment options.     

Endoscopic surgery on the thoracolumbar junction of the spine

The thoracolumbar junction is the section of the truncal spine most often affected by injuries. Acute instability with structural damage to the anterior load-bearing spinal column and post-traumatic deformity represents the most frequent indications for surgery. In the past few years, endoscopic techniques for these indications have partially superseded the open procedures, which are associated with high access morbidity. The particular position of this section of the spine, which lies in the transition area between the thoracic and abdominal cavities, makes it necessary in most cases to partially detach the diaphragm endoscopically in order to expose the surgical site, and this also provides access to the retroperitoneal section of the thoracolumbar junction. A now standardised operating technique, instruments and implants specially developed for the endoscopic procedure, from angle stable plate and screw implants to endoscopically implantable vertebral body replacements, have gradually opened up the entire spectrum of anterior spine surgery to endoscopic techniques.     

经椎弓根截骨技术在胸腰椎后凸畸形中的应用

目的评价经椎弓根椎体内楔形闭合截骨术治疗胸腰椎后凸畸形的临床疗效。方法 23例胸腰椎后凸畸形患者,行椎弓根楔形闭合截骨矫正术,其中陈旧性胸腰椎骨折14例;先天性半椎体畸形5例;强直性脊柱炎4例。观察术前、术后6个月及末次随访矢状面Cobb角、视觉模拟量表（visual analog scale,VAS）评分和Oswestry功能障碍指数（Oswestry disability index,ODI）的变化。结果平均随访34个月,术后后凸Cobb角与术前比较差异有统计学意义（P〈0.05）,末次随访时后凸Cobb角与术后比较无明显丢失（P〉0.05）;术后腰痛及末次随访VAS评分与术前比较差异有统计学意义（P〈0.05）,术后6个月随访ODI与术前比较差异有统计学意义（P〈0.05）。结论经椎弓根椎体内楔形闭合截骨术治疗胸腰椎后凸畸形能获得满意的临床疗效。