Mechanical principle and clinical application of the combined spinal rod-plate and transpedicular screws fixation system

Twenty-one patients with unstable burst fractures of the lower thoracic and lumbar spine were treated with a combined spinal rod-plate and transpedicular screws (CSRP-TPS) fixation system. This system is a new device for disorders of the lower thoracic and lumbar spine. In treatment of spinal fractures, it provided three-column axial distraction and stabilized the injured vertebra in a lordotic position-this maximized the reduction and indirectly achieved a neurologic decompression by ligamentotaxis. This "indirect" neurologic decompression was more successful in cases treated early after injury as the spinal canal area (measured by pre- and postoperative CT) increased 35% in cases treated within one week after injury; 25% in cases treated 7-14 days after injury; and there was little improvement in cases treated more than two weeks following injury. All patients had a minimum follow-up of 12 months. There were no infections, iatrogenic neurologic deficits or instrumentation failures. The CSRP-TPS system gave more improved results over conventional Harrington and segmental spinal instrumentation systems and only required fixation and fusion of three vertebral levels.     

Moss Miami内固定及椎管减压治疗胸腰椎骨折的探讨

目的: 探讨MossMiami内固定及椎管减压治疗胸腰椎骨折的临床疗效。方法:对 18例胸腰椎骨折患者应用MossMiami内固定系统进行复位内固定。结果: 18例患者术中均获得良好复位, 平均随访 14个月 (9~20个月), 骨折全部愈合, 无断钉、断棒、内固定松动等情况。结论: MossMiami内固定操作简便,复位满意, 固定牢靠, 是治疗胸腰椎骨折有效治疗方法之一。     

Z-plate instrumentation in thoracolumbar spinal fractures.

Anterior decompression enables direct access and good canal clearance of the injury level in thoracolumbar spinal fractures, and decompressing the neural elements is shown to be an important factor for neurologic improvement and pain relief in many cases. In this study, results with anterior decompression and Z-plate instrumentation in thoracolumbar spinal fractures are reviewed. Nineteen patients with old spinal fracture (average: 3 years) and neural compression, and 15 patients with fresh thoracolumbar fractures with neurologic deficit and/or major anterior spinal canal obstruction had anterior decompression and Z-plate instrumentation with anterior fusion. Stabilization was protected with thoracolumbar thermoplastic braces for six months. Preoperative kyphotic deformity averaged 20.9 degrees (range: 7 degrees to 64 degrees), while it was an average of 8.0 degrees (range: -12 degrees to 35 degrees) postoperatively. Medullary canal compromise was 41% an average (range: 13% to 67%) and postoperatively it had an average value of 6% (range: 0% to 18%). Patients were followed up an average of 30 months (range: 25 to 36 months). The unchanged positions of bone grafts and statistically insignificant loss of correction in the sagittal plane are accepted as evidence for bony fusion in all patients. Z-plate instrumentation provides stable fixation. Additionally, the technique can be performed easily and has the added benefit of being MRI-compatible.     

The management of burst fractures of the thoracic and lumbar spine. Experience in 53 patients

The optimal treatment of "burst" fractures is one of the more controversial topics in spinal reconstructive surgery. While it is generally considered a stable fracture, recent trends toward operative treatment of burst injuries have raised questions regarding the necessity of stabilization and decompression. A retrospective review was conducted of all patients who presented at the University of Minnesota Hospitals from 1970 to 1980 with closed thoracolumbar spinal fractures. In 354 of 399 patients, records and roentgenograms were adequate for review. Using strict x-ray criteria for classification, 59 patients were found to have burst fractures. One-year follow-up was available on 53 patients. There were 10 thoracic and 43 lumbar fractures. Thirty-one patients had associated injuries. Eleven patients had other spinal fractures. Thirty-eight patients demonstrated neurologic deficits. Twenty-two patients were initially treated nonoperatively, and 31 had early surgery. Operations included laminectomy, posterolateral decompression, posterior spinal fusion usually with Harrington rod instrumentation, and anterior spinal fusion. At follow-up, which averaged more than 3 years, neurologic improvement was found in 68% of the surgical patients who had presented initially with a neurologic deficit. Six patients treated nonoperatively later required surgery. Back pain was more common in the surgical group, disability less common. Radiographic follow-up revealed little increase in deformity in either group. The findings in this study suggest that nonsurgical treatment of patients with burst fractures and normal neurologic function is not likely to result in neurologic deterioration or progressive deformity, but in those with neural deficits, significant neurologic improvement is unlikely, and neurologic deterioration may occur.(ABSTRACT TRUNCATED AT 250 WORDS)     

Complete rotational burst fracture of the third lumbar vertebra managed by posterior surgery. A case report

STUDY DESIGN: Case report of a young man with rotational burst fracture of the third lumbar vertebra, treated by posterior surgery. OBJECTIVES: To describe the management of a rotational burst fracture of the third lumbar vertebra by posterior surgery consisting of reduction, decompression, fusion, and transpedicular instrumentation. SUMMARY OF BACKGROUND DATA: Surgery is the generally recommended means of managing lumbar burst fractures with neurologic deficit. Some surgeons recommend anterior decompression, fusion, and instrumentation. Posterior surgery with decompression through laminectomy, spongioplasty of the vertebral body, interbody fusion of damaged discs, posterolateral fusion, and transpedicular fixation is also a safe and successful management technique. The combined approach consists of posterior decompression, fusion, transpedicular fixation, and anterior fusion using pelvic autografts. The optimum method of management remains in question. METHOD: An 18-year-old man with complete rotational burst fracture of the third lumbar vertebra was treated by posterior surgery. This surgery consisted of reduction, laminectomy, decompression, structure of dural sac tears, spongioplasty of the vertebral body, interbody fusion of both damaged discs, and the implantation of a transpedicular Socon fixator (Aesculap, Tuttlingen, Germany), including a transverse connector. The case was documented by radiographs and computed tomography scans before surgery and after fixator removal 19 months after surgery. RESULTS: The patient healed solidly with no instrumentation failure. The neurologic deficit Frankel Grade B improved to Frankel Grade D. CONCLUSION: Surgery to manage lumbar burst fracture must include reduction, decompression, restoration and fusion of anterior and posterior elements by using autologous pelvic spongious autografts, and anterior or posterior instrumentation. Posterior surgery including suturing of dural sac tears, fusion of damaged structures, and transpedicular fixation is successful in young patients and patients with good bone quality.     

Posterior lumbar interbody fusion using one diagonal fusion cage with transpedicular screw/rod fixation

Posterior lumbar interbody fusion (PLIF) using threaded cages has gained wide popularity for lumbosacral spinal disease. Our biomechanical tests showed that PLIF using a single diagonal cage with unilateral facetectomy does add a little to spinal stability and provides equal or even higher postoperative stability than PLIF using two posterior cages with bilateral facetectomy. Studies also demonstrated that cages placed using a posterior approach did not cause the same increase in spinal stiffness seen with pedicle screw instrumentation, and we concluded that cages should not be used posteriorly without other forms of fixation. On the other hand, placement of two cages using a posterior approach does have the disadvantage of risk to the bilateral nerve roots. We therefore performed a prospective study to determine whether PLIF can be accomplished by utilizing a single diagonal fusion cage with the application of supplemental transpedicular screw/rod instrumentation. Twenty-seven patients underwent a PLIF using one single fusion cage (BAK, Sulzer Spine-Tech, Minneapolis, MN, USA) inserted posterolaterally and oriented anteromedially on the symptomatic side with unilateral facetectomy and at the same level supplemental fixation with a transpedicular screw/rod system. The internal fixation systems included 12 SOCON spinal systems (Aesculap AG, Germany) and 15 TSRH spinal systems (Medtronic Sofamor Danek, USA). The inclusion criteria were grade 1 to 2 lumbar isthmic spondylolisthesis, lumbar degenerative spondylolisthesis, and recurrent lumbar disc herniations with instability. Patients had at least 1 year of low back pain and/or unilateral sciatica and a severely restricted functional ability in individuals aged 28-55 years. Patients with more than grade 2 spondylolisthesis or adjacent-level degeneration were excluded from the study. Patients were clinically assessed prior to surgery by an independent assessor; they were then reassessed at 1, 3, 6, 12, 18, and 24 months postoperatively by the same assessor and put into four categories: excellent, good, fair, and poor. Operative time, blood loss, hospital expense, and complications were also recorded. All patients achieved successful radiographic fusion at 2 years, and this was achieved at 1 year in 25 out of 27 patients. At 2 years, clinical results were excellent in 15 patients, good in 10, fair in 1, and poor in 1. Regarding complications, one patient had a postoperative motor and sensory deficit of the nerve root. Reoperation was required in one patient due to migration of pedicle screws. No implant fractures or deformities occurred in any of the patients. PLIF using diagonal insertion of a single threaded cage with supplemental transpedicular screw/rod instrumentation enables sufficient decompression and solid interbody fusion to be achieved with minimal invasion of the posterior spinal elements. It is a clinically safer, easier, and more economical means of accomplishing PLIF.     

Treatment of unstable fractures of thoracolumbar spine with neurologic injury using a reduction fixation spinal pedicle screws system]

Twenty-six patients with unstable burst fractures, chance fractures and fractures dislocations of the lower thoracic and lumbar spine were treated with a spinal pedical screw reduction fixation system (RF system). This system is a new device designed by Chinese scientists. In biomechanical testing, it provided three-dimensional reduction forces. The special design of angle pedicle screw provided accurate angle to restore the normal thoracic lumbar lordosis and to maintain it. The three-column spine in a lordotic position maximized the reduction and indirectly achieved a neurologic decompression in the spinal canal. All patients had an anatomical reduction by RF system except one case operated two weeks after injury, the spinal canal area increased over 30% by CT (P < 0.01). Except four cases with Frankle A out of twenty patients with neurologic deficits, all other patients had at least one grade progress. Of them one improved from A to D, ten from C and D to normal. These twenty patients were followed-up over six months. All of them maintained anatomical reduction by RF system. Bone grafting had successful fusion by follow-up X-ray examinations. There were no important complications after surgery. The system is of simple structure facilitation implantation and enable the patients beginning ambulatory movements early, therefore it gives more satisfactory results over conventional Harrington and other segmental spinal instrumentation systems.     

Decompression and circumferential stabilization of unstable spinal fractures

A technique of anterior decompression of the spinal canal with anterior strut grafts, followed by posterior instrumentation and local fusion, is described in a group of 18 patients with unstable thoracolumbar fractures. All patients were found to have greater than 50% encroachment of the spinal canal and a preoperative kyphosis of 21.8 degrees. At follow-up 81% of patients with incomplete neurological lesions improved at least one Frankel Grade. Residual encroachment on the spinal canal was 4.6% and at follow-up the kyphotic angle was 17.1 degrees. Complications included one anterior graft loosening (not requiring revision), three loosened rods, only one of which required revision, and one fractured Harrington rod which did not require revision. The authors conclude that this technique is an effective and safe method for treating unstable thoracolumbar injuries and is recommended if anterior instrumentation is unavailable.     

The role of intraoperative ultrasonography in the treatment of thoracic and lumbar spine fractures

The technique of intraoperative ultrasonography is outlined in detail and examples of normal spinal canal anatomy are shown. Twenty-three patients with unstable thoracic and lumbar spine fractures were prospectively treated with Harrington rod reduction and fusion using intraoperative ultrasonography. The pathology at all levels studied corresponded exactly to that seen on preoperative myelograms and computed tomography scans. Intradural pathology also was seen clearly in four patients. This technique makes the use of Harrington rod reduction and posterolateral decompression a possibly safer and more effective method of treating these fractures.     

单枚融合器附加椎弓根螺钉系统在腰椎滑脱治疗中的应用

目的探索以单枚椎间融合器后斜向植入附加椎弓根螺钉系统内固定的后路腰椎椎体间融合术治疗腰椎滑脱症.方法1997年7月～2000年8月,我们收治了各类腰椎滑脱症65例患者(男32例,女33例.年龄28～58岁,平均43岁).其中,峡部型滑脱症(Ⅰ～Ⅱ°)26例,退行性滑脱症25例,腰椎后路减压术后滑脱症7例,发育不良性腰椎滑脱症5例,外伤性滑脱症2例.均有一年以上的下腰痛和/或下肢根性症状且保守治疗无效.所有患者均在减压的基础上行病变节段的单枚螺纹式椎间融合器(BAK)的后斜向植入并附加用椎弓根螺钉系统内固定.结果65例中有59例平均随访达18月,皆达到临床融合.临床效果评价优42例,良14例,无改善3例,差0例.患者主观评定满意41例,基本满意15例,可3例所有患者均无融合器的移位及椎弓根螺钉松动,患者主观满意率93%.结论经侧后方斜向植入单枚螺纹状椎间融合器并附加椎弓根螺钉内固定的后路腰椎椎体间融合术式能充分完成后路减压,并能保证可靠的融合,适用于滑脱程度严重、滑脱倾向大的患者,不失为一种比较理想的治疗各种腰椎滑脱症的术式.     

Segmental spinal instrumentation in idiopathic scoliosis. A preliminary report

Eighty-six patients with idiopathic scoliosis who underwent a posterior spinal fusion using sublaminar segmental spinal instrumentation were analyzed retrospectively. There were two operative groups: group 1, 66 patients who had Harrington rod instrumentation and segmental wiring, and group 2, 20 patients who had Luque rod instrumentation. The clinical and radiographic data of the two groups were similar except for the passage of more sublaminar wires and increased intraoperative blood loss in group 2. Twenty intraoperative or postoperative complications occurred in 19 patients (22%) including 14 neurologic complications. Three patients (3%) had major spinal cord injuries, while 11 patients (13%) had transient sensory changes. There was no significant difference in the incidence of neurologic complications between group 1 or group 2. The remaining intraoperative complications were due either to anesthesia, positioning during surgery, or technique (dural tear). Late complications occurred in two patients in group 1 only: one each with rod breakage and hook displacement. Only one patient (1%) has required additional surgery. Our results indicate that although segmental instrumentation can be beneficial in idiopathic scoliosis, the incidence of complications, primarily neurologic, will be higher than expected. The major reason appears to be surgeon inexperience with passage of sublaminar wires. As experience increases, the incidence of complications declines and becomes comparable with conventional Harrington rod instrumentation alone.     

Single-stage posterolateral transpedicle approach for spondylectomy, epidural decompression, and circumferential fusion of spinal metastases

STUDY DESIGN: Retrospective review of prospectively maintained institutional spine database. OBJECTIVES: To assess the pain, neurologic, and functional outcome of patients with metastatic spinal cord compression using a posterolateral transpedicular approach with circumferential fusion. SUMMARY OF BACKGROUND DATA: Patients with spinal metastases often have patterns of disease requiring both an anterior and posterior surgical decompression and spinal fusion. For patients whose concurrent illness or previous surgery makes an anterior approach difficult, a posterior transpedicular approach was used to resect the involved vertebral bodies, posterior elements, and epidural tumor. This approach provides exposure sufficient to decompress and instrument the anterior and posterior columns. METHODS: During the past 15 months, 25 patients were operated on using a posterolateral transpedicular approach. The primary indications for surgery were back pain (15 patients) and neurologic progression (10 patients). All patients had vertebral body disease, and 21 patients had high-grade spinal cord compression from epidural disease as assessed by magnetic resonance imaging. Seven patients underwent preoperative embolization for vascular tumors. In each patient, the anterior column was reconstructed with polymethyl methacrylate and Steinmann pins and the posterior column with long segmental fixation. RESULTS: All patients achieved immediate stability. Pain relief was significant in all 23 patients who had had moderate or severe pain. Neurologic symptoms were stable or improved in 23 patients. One patient with an acutely evolving myelopathy was immediately worse after surgery, and one patient had a delayed neurologic worsening, progressing to paraplegia. CONCLUSIONS: The posterolateral transpedicular approach provides a wide surgical exposure to decompress and instrument the anterior and posterior spine. This technique avoids the morbidity associated with anterior approaches and provides immediate stability. Vascular tumors may be removed safely after embolization. Patients can be mobilized early after surgery.     

Management of thoracolumbar fractures with accompanying neurological injury.

The optimal surgical approach for spinal canal reconstruction of thoracolumbar fractures is controversial, and the relationship between spinal canal reconstruction and neurological recovery remains unclear. To address these issues, 22 consecutive cases of thoracolumbar fracture with accompanying neurological deficit were reviewed. Neurological status was graded at the time of admission, postoperatively, and at a mean of 15 months postinjury. By using preoperative and postoperative radiographs and computed tomographic scans, the degree of spinal canal compromise was quantified in the sagittal, coronal, and axial planes. All fractures were stabilized by posterior instrumentation and fusion, and in 10 injuries, retropulsed vertebral body fragments were further reduced by posterolateral decompression. Spinal canal dimensions, neurological function, and operative approach were compared by using nonparametric statistical analysis. The greater the initial spinal canal compromise, the more severe the neurological deficit (P = 0.04). With injuries involving L1 and above, this relationship increased (P = 0.003). The extent of spinal canal reconstruction failed to correlate with neurological recovery. Compared with spinal instrumentation alone, transpedicular decompression showed no benefit in terms of postoperative canal dimensions or neurological outcome. On the basis of this experience, transpedicular decompression offers no advantage over spinal instrumentation alone. The relationship between initial spinal canal encroachment and neurological deficit demonstrates that the degrees of bony and neurological injury directly reflect the kinetic energy transferred at the time of impact. The lack of correlation between the extent of spinal canal reconstruction and neurological recovery suggests that ongoing neural compression/distortion contributes little to the overall neurological injury.     

后路一期半椎体切除治疗先天性脊柱侧凸的疗效与并发症

目的评价后路一期半椎体切除椎弓根螺钉内固定治疗完全分节半椎体所致先天性脊柱侧后凸的临床效果。方法回顾性分析56例（女32例,男24例）接受手术治疗的半椎体所致先天性脊柱侧凸的患者。所有病例均行后路一期半椎体切除,均应用椎弓根螺钉技术进行固定,随访24～58个月,平均32.9个月。术前、术后及随访时均摄站立位全脊柱正侧位X线片,对冠状面和矢状面Cobb角、躯干偏移进行测量分析。同时复习病历,统计手术时间、出血量以及并发症情况。结果手术时间120～365min,平均210min;术中出血量150～2100ml,平均812ml;固定椎体节段2～11个,平均5个。冠状面节段性侧凸Cobb角术前平均42.4°,术后11.5°,末次随访14.1°,矫形率为72.9%;节段性后凸Cobb角术前平均42.0°,术后12.6°,末次随访14.5°,矫形率为70.0%;躯干偏移术前平均16.2mm,术后14.8mm,末次随访8.0mm。术前存在神经症状的2例患者均得到良好的缓解。1例出现伤口延迟愈合;2例手术后出现椎弓根螺钉切割;2例出现断棒;1例术后出现交界性后凸。结论后路一期半椎体切除椎弓根螺钉固定可直接去除致畸因素,在冠状面和矢状面均可获得满意的矫形,同时可以获得脊髓的360°减压,可缩短时间、减少融合节段。但是对于年龄较小的患儿而言,内固定失败,主要是凸侧椎弓根骨折、螺钉的切割,需要引起充分的重视。     

Neurologic injury and recovery patterns in burst fractures at the T12 or L1 motion segment

Fourteen consecutive patients with burst fractures at T12 or L1, partial paralysis, and more than 30% canal compromise were prospectively evaluated pretreatment and posttreatment with roentgenograms to determine the initial fracture pattern, CT scans to determine the percent canal compromise and subsequent improvement, and a quantitative motor trauma index scale and bladder sphincter evaluation to determine neurologic recovery. The follow-up period averaged 32 months (range, 12-50 months). Treatment was as follows: nonoperative (three patients), Harrington rods and fusion (seven patients), and Harrington rods and fusion followed by anterior decompression and fusion (four patients). The initial severity of paralysis did not correlate with the initial fracture roentgenographic pattern or the amount of initial CT canal compromise. Neurologic recovery did not correlate with the treatment method or amount of canal decompression. Subsequent recovery did correlate with the initial fracture pattern. If the patient had a Type I or Type II fracture (both greater than 15 degrees kyphosis), greater than 90% neurologic recovery occurred, regardless of treatment. If the patient had a Type III fracture (less than 15 degrees kyphosis and the maximal canal compromise where bone encircles the canal) less than 50% neurologic recovery occurred. If the patient had a Type IV fracture (less than or equal to 15 degrees kyphosis and the maximal canal compromise at the level of the ligamentum flavum), the neurologic recovery was variable. Prognosis for neurologic recovery can be made based on initial roentgenograms. If greater than 15 degrees kyphosis is present, there is a good prognosis.(ABSTRACT TRUNCATED AT 250 WORDS)     

Spinal canal decompression in traumatic thoracolumbar burst fractures: posterior distraction rods versus transpedicular screw fixation.

Although the benefit of spinal canal decompression of traumatic thoracolumbar burst fractures is controversial, it remains a desirable procedure, as many reports describe improved neurologic outcome with spinal canal reconstruction. The optimal type of posterior instrumentation for reconstructing the spinal canal is unclear. This study focused on the efficacy of posterior distraction rods versus transpedicular screw fixation implants in decompressing the spinal canal and on the relationship between the amount of canal decompression and subsequent neurologic recovery. A medical records review was conducted to identify all patients surgically treated for traumatic burst fractures of the thoracolumbar spine from January 1, 1987 to June 30, 1989. Sixty-seven patients were selected by this review, and, of these, 30 had had both preoperative and postoperative CT scans. We could find no bias among patients who received both preoperative and postoperative CT scans as compared to those who did not, therefore the 30 patients were considered to be a random sample of the total population of 67. A retrospective study was then conducted on the 30 patients with surgically treated burst fractures--15 treated with posterior distraction rods and 15 treated with AO Fixator Interne transpedicular screw fixation implants. Preoperative and postoperative spinal canal cross-sectional areas were measured directly from the scaled CT scans. The area of most severe compromise was compared with an internal standard defined as the next, caudal, uncompromised spinal level, and the percentage of preoperative and postoperative canal compromise was calculated.(ABSTRACT TRUNCATED AT 250 WORDS)     

钉棒及钩棒系统治疗胸腰椎多节段脊柱骨折

目的评价钉棒及钩棒系统治疗胸腰椎多节段脊柱骨折的临床疗效。方法23例多节段胸腰椎骨折患者，后路切开复位，选择性椎管减压．钉棒或钩棒系统内固定及后外侧植骨融合进行手术治疗。其中相邻多节段型13例，非相邻多节段型8例，混合型2例。结果全组病例平均随访14个月，未发现内固定物松动、断离，无继发性脊柱后凸畸形加重。椎体高度由术前平均48．4％恢复至术后平均92．4%。2例完全性及11例不完全性脊髓损伤者．脊髓神经功能获改善。结论在椎管进行充分减压的基础上．钉棒及钩棒系统能有效复位椎体骨折，重建脊柱稳定性，是多节段胸腰椎不稳定性骨折合并脊髓神经损伤后路手术的理想选择。     

Neurologic return versus cross-sectional canal area in incomplete thoracolumbar spinal cord injuries

Twenty-four patients with incomplete spinal cord injuries secondary to burst fractures of the thoracolumbar spine were reviewed an average of 26 months after their injury. No patient had had a specific attempt to decompress neural elements but the majority had posterior instrumentation and fusion for spine realignment and stabilization. The amount of neurologic recovery in each patient was compared to the final area of the spinal canal as determined by CT scan. It was concluded that there was no correlation between neurologic improvement and the amount of spinal canal encroachment. In addition, posterior instrumentation to realign the spine will usually restore canal patency to greater than 50% of normal.     

全椎板减压椎弓根钉棒内固定治疗多节段颈椎管狭窄

目的评价对多节段颈椎椎管狭窄症患者行后路全椎板切除、椎管减压、植骨融合并椎弓根内固定术的治疗效果。方法 2002年2月~2008年12月采用后路全椎板切除、椎管减压、植骨融合并椎弓根内固定术治疗多节段颈椎椎管狭窄患者35例,其中男20例,女15例;平均年龄为62.5岁。退变性椎管狭窄10例,发育性椎管狭窄12例,后纵韧带骨化伴椎管狭窄13例。患者颈椎椎管狭窄的节段均≥3个。术前日本骨科学会（Japanese Orthopaedics Association,JOA）评分为6.7±1.2分。结果手术时间平均为135 min。所有患者均获随访,随访时间为3~36个月,平均12.5个月,随访期间未发现严重的手术并发症发生。术后1周JOA评分为8.2±1.5分,与术前相比差异有统计学意义（P〈0.05）,术后6个月JOA评分为12.8±1.8分,与术后1周相比差异有统计学意义（P〈0.05）。结论椎管减压、植骨融合并椎弓根内固定术是治疗多节段颈椎椎管狭窄行之有效的方法,既解决了减压不彻底的问题,又保证了颈椎的稳定性;但颈椎椎弓根螺钉技术需要术者扎实的局部解剖知识以及丰富的置钉经验。     

Modified transpedicular approach for the surgical treatment of severe thoracolumbar or lumbar burst fractures.

BACKGROUND CONTEXT: Conventional transpedicular decompression of the neural canal requires a considerable amount of lamina, facet joint and pedicle resection. The authors assumed that it would be possible to remove the retropulsed bone fragment by carving the pedicle with a high-speed drill without destroying the vertebral elements contributing to spinal stabilization. In this way, surgical treatment of unstable burst fractures can be performed less invasively. PURPOSE: The purpose of this study is to demonstrate both the possibility of neural canal decompression through a transpedicular approach without removing the posterior vertebral elements, which contribute to spinal stabilization, and the adequacy of posterior stabilization of severe vertebral deformities after burst fractures. STUDY DESIGN: Twenty-eight consecutive patients with complete or incomplete neurological deficits as a result of the thoracolumbar burst fractures were included in this study. All patients had severe spinal canal compromise (mean, 59.53%+/-14.92) and loss of vertebral body height (mean, 45.14%+/-7.19). Each patient was investigated for neural canal compromise, degree of kyphosis at fracture level and fusion after operation by computed tomography and direct roentgenograms taken preoperatively, early postoperatively and late postoperatively. The neurological condition of the patients was recorded in the early and late postoperative period according to Benzel-Larson grading systems. The outcome of the study was evaluated with regard to the adequate neural canal decompression, fusion and reoperation percents and neurological improvement. METHODS: Modified transpedicular approach includes drilling the pedicle for removal of retropulsed bone fragment under surgical microscope without damaging the anatomic continuity of posterior column. Stabilization with pedicle screw fixation and posterior fusion with otogenous bone chips were done after this decompression procedure at all 28 patients included in this study. RESULTS: Twenty-three of 28 patients showed neurological improvement. The percent of ambulatory patients was 71.4% 6 months after the operation. The major complications included pseudarthrosis in five patients (17.8%), epidural hematoma in one (3.5%) and inadequate decompression in one (3.5%). These patients were reoperated on by means of an anterior approach. Of the five pseudarthrosis cases, two were the result of infection. CONCLUSION: Although anterior vertebrectomy and fusion is generally recommended for burst fractures causing canal compromise, in these patients adequate neural canal decompression can also be achieved by a modified transpedicular approach less invasively.