Keio University School of Medicine, Tokyo, Japan.
Spine (Phila Pa 1976). 2010 Sep 15;35(20):1836-42. doi: 10.1097/BRS.0b013e3181d3cfde.
Prospective clinical series.
To determine how many thoracic scoliotic pedicles have cancellous versus cortical versus absent channels.
Although morphologic evaluations of thoracic pedicles have been well reported, the results do not practically reflect clinical findings during actual pedicle screw placement. We propose a novel pedicle channel classification describing the osseous anatomy encountered during pedicle probe insertion.
We noted 4 pedicle types in 53 consecutive scoliosis patients. Type A: pedicle probe smoothly inserted without difficulty; the morphology is described as a "Large Cancellous Channel." Type B: pedicle probe inserted snugly with increased force; described as a "Small Cancellous Channel." Type C: pedicle probe cannot be manually pushed but must be tapped with a mallet down the pedicle into the body; described as a "Cortical Channel." Type D: pedicle probe cannot locate a channel thus necessitating a "juxtapedicular" screw position; described as a "Slit/Absent Channel." The average age at time of surgery was 23.4 ± 16.7 years. Diagnoses included idiopathic scoliosis (n = 38) and syndromic scoliosis (n = 15). The average main thoracic Cobb angle was 73° ± 26°. Evaluation of pedicle morphology of the 4 types was also performed in 21 consecutive cases of adolescent idiopathic scoliosis using preoperative computed tomography images.
A total of 1021 pedicles with screws placed were evaluated. The average percent per type was as follows: 61.0% type A; 29.2% type B, 6.8% type C, and 3.0% type D. On the convexity, 98.2% of pedicles were type A or B versus 81.5% on the concavity (P < 0.05). There were significant differences between adolescent versus adult idiopathic scoliosis (P = 0.007), and syndromic scoliosis versus adult idiopathic scoliosis (P = 0.017) regarding pedicle morphologic proportions. There was a significant tendency toward a decrease in the proportion of type A pedicles, an increase in the proportion of type B pedicles as the Cobb angle increased (P < 0.0001). Evaluation based on 312 thoracic pedicles in 21 consecutive adolescent idiopathic scoliosis patients using preoperative computed tomography axial images confirmed assumptions of the 4 pedicle types.
We propose a classification for pedicle channels describing the osseous anatomy encountered during pedicle probe insertion. Based on the classification, surprisingly, we found during surgery that 90% of thoracic pedicles had a cancellous channel, whereas 7% had a cortical channel and only 3% had an absent channel.
前瞻性临床系列研究。
确定有多少胸椎脊柱侧凸椎弓根有松质骨、皮质骨或无通道。
尽管对胸椎椎弓根的形态学评估已有很好的报道，但结果实际上并不能反映实际椎弓根螺钉放置过程中的临床发现。我们提出了一种新的椎弓根通道分类方法，描述了在椎弓根探针插入过程中遇到的骨解剖结构。
我们在 53 例连续脊柱侧凸患者中发现了 4 种椎弓根类型。类型 A：椎弓根探针顺利插入，无困难；形态描述为“大松质骨通道”。类型 B：椎弓根探针插入时需要增加力，但仍能插入；描述为“小松质骨通道”。类型 C：椎弓根探针不能用手推入，只能用锤子敲击椎弓根进入体部；描述为“皮质通道”。类型 D：椎弓根探针无法定位通道，因此需要采用“椎弓根旁”螺钉位置；描述为“裂隙/无通道”。手术时的平均年龄为 23.4 ± 16.7 岁。诊断包括特发性脊柱侧凸（n = 38）和综合征性脊柱侧凸（n = 15）。平均主胸 Cobb 角为 73°±26°。在 21 例青少年特发性脊柱侧凸患者的术前计算机断层扫描图像中，还对 4 种类型的椎弓根形态进行了评估。
共评估了 1021 个带有螺钉的椎弓根。每种类型的平均百分比如下：61.0%类型 A；29.2%类型 B，6.8%类型 C，3.0%类型 D。凸侧 98.2%的椎弓根为 A 型或 B 型，凹侧为 81.5%（P < 0.05）。青少年特发性脊柱侧凸与成人特发性脊柱侧凸（P = 0.007）以及综合征性脊柱侧凸与成人特发性脊柱侧凸（P = 0.017）之间，椎弓根形态比例存在显著差异。随着 Cobb 角的增加，A 型椎弓根的比例呈显著下降趋势，B 型椎弓根的比例呈显著增加趋势（P < 0.0001）。在 21 例连续的青少年特发性脊柱侧凸患者的 312 个胸椎椎弓根中，使用术前计算机断层轴向图像进行评估，证实了 4 种椎弓根类型的假设。
我们提出了一种用于描述椎弓根探针插入过程中遇到的骨解剖结构的椎弓根通道分类方法。根据分类，令人惊讶的是，我们发现术中 90%的胸椎椎弓根有松质骨通道，7%有皮质骨通道，只有 3%有无通道。
