脊柱截骨术治疗创伤僵硬性胸腰段后凸畸形的解剖与临床研究

目的探讨经椎弓根椎体楔形截骨术治疗创伤僵硬性胸腰段后凸畸形的安全性和有效性。方法解剖研究中将16具新鲜胸腰段脊柱标本按不同脊柱截骨术分为3组,A组：脊柱开放-闭合截骨术,B组：经椎弓根椎体楔形截骨术,C组：改良经椎弓根椎体楔形截骨术（截骨包括上位椎间盘后半部分）。测量截骨前后Cobb角的变化、椎体高度和椎体前缘高度的变化。临床研究中共26例患者,其中男性18例,女性8例,平均36岁。受伤至本次手术时间3个月～11年,平均25个月。入院前治疗包括非手术治疗9例,手术治疗17例。神经损伤程度按照Frankel分级：A级10例,B级2例,C级10例,D级2例,E级2例。本组病例均有不同程度的腰背部疼痛,VAS评分平均4．5分（2．5～6．0分）。后凸角20°～75°,平均35°。根据后凸角大小选择行后路经椎弓根椎体楔形截骨术或改良椎体楔形截骨术。结果解剖研究胸腰段标本中A组平均纠正（38．0±2．5）°,B组（36．0±3．6）°,C组（49．0±2．0）°。A组椎体高度平均增加（13．8±1．4）mm,椎体前缘增加（30．2±2．5）mm,而B、C组椎体高度平均短缩（2．8±0．8）mm和（3．8±0．7）mm,前缘增加（25．0±1．2）mm和（2．2±0．9）mm。临床研究患者均获随访,随访时间10个月～6年,平均12．5个月,患者获得满意减压和后凸畸形矫正,术后后凸角度平均为10．8°（0°～40°）,脊柱后凸畸形平均矫正24°。50％患者的神经功能得到了不同程度恢复,全瘫患者恢复率为30％,主要是感觉功能恢复,而不全瘫患者的恢复率为64．3％,感觉和运动功能均有恢复。腰背部疼痛有不同程度好转,VAS评分平均2．3分（1．0～3．5分）。结论创伤僵硬性胸腰段后凸畸形患者可以选择经椎弓根椎体楔形截骨术或改良经椎弓根椎体楔形截骨术。术后可获得满意的减压效果和后凸畸形纠正,神经功能有不同程度恢复,腰背部疼痛有不同程度好转。     

Predictors of kyphotic deformity in osteoporotic vertebral compression fractures: a radiological study

Purpose

To report the radiological predictors of kyphotic deformity in osteoporotic vertebral compression fractures (OVCF).

Methods

This is a retrospective study of 64 consecutive patients with OVCF. We studied the radiographic features in the immediate post-injury image of patients, who developed significant (more than 30°) segmental kyphotic deformity at final follow-up and compared them with those patients who did not.

Results

Thirty-three (82.5 %) out of 40 patients with fracture at thoracolumbar (TL) junction, 5 (33.3 %) patients out of 15 with fracture at lumbar (L) spine and 7 (77.7 %) patients out of 9 with fracture at thoracic (T) spine developed significant segmental kyphotic deformity. Forty-one (75.9 %) [TL-33 (80.5 %), L-4 (33.33 %) and T-4 (80 %)] out of 54 [TL-37 (68.51 %), L-12 (22.23 %) and T-5 (9.26 %)] patients with superior endplate fracture developed significant segmental kyphotic deformity. Forty patients (86.9 %) [TL-28 (70 %), L-6 (15 %) and T-6 (15 %)] out of 46 [TL-32 (69.56 %), L-8 (17.4 %) and T-6 (13.04 %)] with anterior cortical wall fracture developed significant segmental kyphotic deformity. Five patients (71.42 %) [TL-2 (40 %) and T-3 (60 %)] out of 7 [TL-02 (28.58 %), L-01 (14.28 %), T-04 (57.14 %)] with adjacent level fracture developed significant segmental kyphotic deformity. The average immediate post-injury kyphosis of 11° (5°–25°) increased to 29° (15°–50°) at final follow-up.

Conclusion

Progressive segmental kyphotic collapse following an OVCF seems unavoidable. Patients with TL junction and superior endplate fracture are probably at the highest risk for significant segmental kyphotic deformity.     

单节段“蛋壳”式椎体截骨术矫正胸腰段脊柱后凸畸形

目的研究单节段"蛋壳"式椎体截骨术矫正胸腰段脊柱后凸畸形的临床疗效。方法回顾分析2002年6月~2006年6月收治的骨折后陈旧性胸腰段椎体后凸畸形患者共21例,既往治疗包括非手术治疗8例,后路手术治疗13例。本组所有患者均有不同程度的腰背痛,疼痛的VAS评分为4.3~7.5分,平均5.6分;神经损伤程度按照Frankel分级进行评定,A级5例,B级3例,C级7例,D级2例,E级4例。本组后凸畸形的Cobb角为28°~75°,平均48°,后凸顶端均为原骨折椎体节段,所有患者均采用后路单节段"蛋壳"技术于后凸顶椎处进行椎体截骨,通过椎弓根固定系统加压固定。观察手术前后后凸畸形的矫正率、疼痛VAS评分及神经功能的恢复。结果所有患者均获得随访,随访6~48个月,平均22个月。手术平均用时212min(128~360min),平均出血量为800mL(400~2200mL)。术后后凸角平均为13°,平均矫正约35°;腰背部疼痛均有明显缓解,术后随访VAS评分平均2.3分(1.0~3.5分),比术前平均降低3.3分。结论单节段"蛋壳"式椎体截骨术截骨后前中后三柱均为骨性接触,融合率高,矫正效果可靠(平均35°),避免了前方大血管损伤的危险,此术式在矫正胸腰段脊柱后凸畸形这一方面是一种安全有效的方法。     

Use of hinged rods for controlled osteoclastic correction of a fixed cervical kyphotic deformity in ankylosing spondylitis

Cervical kyphosis in patients with ankylosing spondylitis (AS) can be severely disabling. Surgical treatment of this disorder is technically demanding, however, with a considerable risk of neurological and vascular injuries. The extension osteotomy is a well-described posterior treatment for this condition, but this approach presents the risk of acute subluxation and spinal column translation during the reduction. In this paper, the authors report the novel use of a hinged posterior cervical rod for controlled correction of cervical kyphosis. After sustaining a traumatic spinal fracture, a 57-year-old man with AS developed a delayed cervical flexion deformity. The patient was neurologically intact, but suffered from disabling impairment in horizontal gaze and activities of daily living, and from neck pain. The patient subsequently underwent surgical correction via a posterior cervical extension osteotomy at C7-T1 with manual extension of the neck for osteoclastic reduction of the cervical kyphosis. Controlled correction was performed by using a hinged rod affixed to posterior cervical and thoracic screws, allowing for free sagittal correction while restricting translational forces. Once the desired angle of correction was achieved, the hinge connector was locked, transforming the rod into a rigid device for permanent internal fixation. The use of hinged rods in cervical kyphosis correction provides a controlled method for reduction at the osteotomy site, decreasing the risk of neurological injury.     

Polysegmental lumbar osteotomies and transpedicled fixation for correction of long-curved kyphotic deformities in ankylosing spondylitis. Report on 177 cases

Despite conservative therapy in ankylosing spondylitis, kyphotic deformities are common. Mono-segmental lumbar osteotomy had a high complication rate. Therefore, a poly-segmental lordosis osteotomy of the lumbar spine was introduced in four to six segments using trans-pedicled screws and threaded rods in eight to ten segments (isolated correction is possible for each segment). Instead of dangerous short kinking, a poly-segmental lordosis osteotomy results in harmonious lordosis with a correction per segment of about 10 degrees, and complications are decreased. Of 177 patients undergoing the operation, there was a 2.3% mortality rate with cardiopulmonary problems, 2.3% with irreversible complications, and 18.1% with reversible complications, mostly small root lesions, of which 7% were reoperated. The 173 surviving patients had a correction of 43%, and improvement in body height of 9 cm, and improvement of flexion by 57%. Fifty-three patients have been followed for more tha 18 months. the visual axis in all cases was horizontal. No pseudoarthrosis occurred. After correction, the frequent spondylodiscitis healed. Ninety-two percent were pain free compared with 15% before the operation. Loss of correction of body height was 20%, of flexion 4%, and of the lordosis 7%, which was 18% in 37 patients after three years.     

Spondylodiscitis in kyphotic deformity of ankylosing spondylitis and its healing affected by dorsal correction osteotomies. Report of 33 patients

Out of 144 patients with kyphotic deformities in Ankylosing spondylitis 33 (23%) had 45 disco-vertebral lesions of the spondylodiscitic type. They were characterized by osteolyses, scleroses and absence of syndesmophytes. 5 had additional arch fractures. All were localized in or below the apical vertebra in the lumber or the lower thoracic spine. Compared with the total collective strong pain, high sedimentation rates and extravertebral manifestations were more frequent, osteoporosis rare, and the degree of kyphosis and the types of ossification same. The radiology showed the lesions as inflammatory etiology. Functionally, however, they are pseudarthroses. All spines were lordosed by dorsal osteotomies and therewith statically corrected and for one year externally immobilized. The spondylodeses fusioned in this time. Complications did not occur on account of the spondylodiscites. The therapy of kyphosis had an influence on the spondylodiscites. They all healed except for one. After a follow up of two years 98% were completely fused, also those with non-identical levels of correction and lesion. The loss of correction in the segments of lesion was negligibly more than in the total collective. 91% of the patients were pain-free compared to 12% preoperatively. The spondylodiscites were no hindrance for dorsal lordosing osteotomies and can be treated successfully by means of this static correction and the immobilisation.     

Single-stage posterior instrumentation and anterior debridement for active tuberculosis of the thoracic and lumbar spine with kyphotic deformity

Objective  

The purpose of this study was to validate the efficacy and safety of single-stage posterior instrumentation and anterior debridement for treatment of active spinal tuberculosis with kyphotic deformity.     

Biomechanical analysis of Ponte and pedicle subtraction osteotomies for the surgical correction of kyphotic deformities

Purpose

Biomechanical analysis of Ponte (PO) and pedicle subtraction osteotomies (PSO) in kyphotic deformity instrumentation.

Methods

Patient-specific biomechanical model was used to computationally simulate seven hyperkyphotic instrumentation cases with three osteotomy strategies—1-level PSO, 3-level PO, or 6-level PO; forces within the instrumented spine were assessed and results were analyzed through rANOVA tests.

Results

Corrections with multi-level PO were close to those with one-level PSO. In upright position, average implant forces were from 225 to 280 N and rod bending moments were around 10 Nm with no significant difference between the three strategies (p < 0.05). In simulations of 30° flexion, rod bending moments increased by 38, 2, and 8 %, implant forces increased by 28, 23 and 26 % for the 1-level PSO, 3-level PO, and 6-level PO, respectively. Correction per vertebral level was smaller than the maximum correction allowed by PO and PSO.

Conclusions

Multi-level PO allows similar kyphotic correction to 1-level PSO in spinal deformities with mixed indications for PO and PSO. Loads on the instrumentation constructs in PSO were higher than multi-level PO and higher in 6-level PO than 3-level PO. High loads were located more on the osteotomy sites. The rod shape should be adapted to the anticipated spine correction on the osteotomy sites.

     

A novel mathematical model of the sagittal spine: application to pedicle subtraction osteotomy for correction of fixed sagittal deformity.

BACKGROUND CONTEXT: The C7 plumb line method oversimplifies the true complexity of the spine. In a previous study, we mathematically modeled the normal spine using the spline function, enabling quantification of previously undescribed measurements such as area under the curve (AUC) and average sagittal position. The spine in fixed sagittal imbalance and the results of surgical correction have not been studied in a similar manner. PURPOSE: To quantitatively evaluate changes in spinal conformation in patients who underwent pedicle subtraction osteotomy (PSO) using measures derived from the spline model and to correlate these changes with functional outcome. STUDY DESIGN: Application of a mathematical model to a cohort of patients who underwent deformity surgery. PATIENT SAMPLE: Thirty-four consecutive patients with fixed sagittal imbalance who underwent PSO from 2001 to 2003. OUTCOME MEASURES: Preoperative and postoperative 22-item Scoliosis Research Society (SRS-22) Outcomes Questionnaire scores were used for functional assessment. METHODS: Radiographs of the 34 patients who underwent thoracic or lumbar PSO with at least 2 years of follow-up were examined at three time points. The posterosuperior aspect of each vertebral body was chosen as a representative point for the spinal sagittal curve. A cubic spline function was derived from these points. From this function, the AUCs and average sagittal positions of the thoracic, lumbar, and thoracolumbar segments were calculated. RESULTS: The average sagittal position does not overlap the C7 plumb line in deformity patients, but is a much more stable measure. In the lumbar PSO cohort, the lumbar AUC and average sagittal position were not significantly different among normal, preoperative, and postoperative groups. The thoracic and thoracolumbar AUCs and average sagittal positions were dramatically more positive in the preoperative cohort compared with normals; these values significantly decreased toward neutrality after lumbar PSO, but remained abnormal. In the thoracic PSO cohort, the lumbar, thoracic, and thoracolumbar AUCs and average sagittal positions were not significantly different among normal, preoperative, and postoperative groups. The changes in thoracolumbar AUC and average sagittal position were better predictors of the SRS-22 total score than the change in C7 plumb line. CONCLUSIONS: The average sagittal position more comprehensively captures the nuances of a nonlinear spinal curve. Subcurve analysis enabled by the spline model is particularly helpful in assessing deformity and surgical correction on a segmental level. Increased sensitivity to the nuances of the spinal curve in this model results in superior correlation with clinical outcomes when compared with the C7 plumb line. We feel that a critical examination of the spinal curve will lead to improved understanding of deformity and planning for an optimal correction.     

Compensatory mechanism of the spine after corrective surgery without lumbar-sacral fixation for traumatic thoracolumbar kyphotic spine deformity

Background

It remains unclear whether long fusion including lumbar-sacral fixation is needed in corrective surgery to obtain good global sagittal balance (GSB) for the treatment of traumatic thoracolumbar kyphotic spine deformity. The purposes of this study were to evaluate compensatory mechanism of the spine after corrective surgery without lumbar-sacral fixation and to evaluate the parameters affecting the achievement of good GSB post-operatively.

Use of the scapular spine in lumbar fusion procedures: cadaveric feasibility study. Laboratory investigation

OBJECT: Graft sources for lumbar fusion include synthetic materials, donor grafts, and autologous bone such as the iliac crest. Considering the data indicating that autologous bone grafts generate the best results for fusion, the next logical step is to seek alternative donor sites in an attempt to reduce the complications associated with these procedures. To the authors' knowledge, autologous scapula has not been explored as a potential source for posterior lumbar fusion graft material. Therefore, the following study was performed to verify the utility of this bone in these procedures. METHODS: Six adult cadavers (mean age 71 years), four formalin-fixed and two fresh specimens, were used in this study. With the cadaver in the prone position, an incision was made over the spine of the scapula. Soft tissues were stripped from the middle of this region of the scapula, and bone segments were removed with a bone saw and used for a posterior lumbar fusion procedure. RESULTS: A mean length of 11.5 cm was measured for the spine of the scapula and the mean thicknesses of this bone at its medial part, segment just medial to the spinoglenoid notch, and acromion were 1 cm, 2.2 cm, and 2.5 cm, respectively. No obvious injury to surrounding vessels or nerves was found using this procedure, and adequate fusion was achieved with it. CONCLUSIONS: Following clinical testing, such a bone substitute as autologous scapular spine might be a reasonable alternative to iliac crest grafts for use in posterior lumbar fusion procedures.     

The surgical treatment and related management for post-tubercular kyphotic deformity of the cervical spine or the cervico-thoracic spine

Purpose  

The outcomes of surgical treatment and related complications of post-tubercular kyphotic (PTK) deformity of the cervical spine or the cervico-thoracic spine were evaluated.     

The relationship between vertebral body deformity and disc degeneration in lumbar spine of the senile

This study provides an investigation of the relationship between vertebral deformities and disc degeneration in patients with senile osteoporosis using biomechanical and medical imaging methods. The finite element analysis showed that stress concentration in the central area of the vertebral body is much decreased with disc degeneration, indicating that load transmission has been altered. Radiography and MRI suggested that vertebral deformities are related to the height and degeneration of the disc just below this vertebral body. When a disc has decreased height or degeneration, the vertebral body just above it is less likely to be deformed for patients with spinal osteoporosis. Received: 22 February 1997 Revised: 26 July 1997 Accepted: 1 August 1997