Reidy Declan, Ahn Henry, Mousavi Payam, Finkelstein Joel, Whyne Cari M
Orthopaedic Biomechanics Laboratory, Sunnybrook and Women's College Health Sciences Centre, Toronto, Ontario, Canada.
Spine (Phila Pa 1976). 2003 Jul 15;28(14):1534-9.
A biomechanical cadaveric study of thoracic and lumbar vertebrae with simulated metastases quantifying intravertebral pressures during transpedicular vertebroplasty.
To compare intravertebral pressures during percutaneous vertebroplasty in vertebrae with and without simulated lytic metastases.
Percutaneous vertebroplasty is designed to provide stability to vertebrae weakened by osteoporosis or metastatic disease. The complication rate is higher when the procedure is used for the treatment of lytic vertebral lesions. The major complications reported are radiculopathy, spinal cord compression, and embolic phenomena.
Ten fresh-frozen cadaveric vertebrae were tested intact (7 lumbar, 3 thoracic) and 7 were tested with simulated lytic defects (4 lumbar, 3 thoracic). Defects were created by replacing a core of cancellous bone with soft tumor tissue in the center of the vertebral body. Simplex P (Howmedica Osteonics, Mahwah, NJ) cement was injected into each vertebra through a unipedicular approach at a constant rate of 3 mL per minute. Cement volume, injection force, and intravertebral pressures at the posterior vertebral body wall were recorded. Following the procedure, the vertebrae were sectioned to visualize cement and tumor disbursement.
There was no significant difference between the two groups for age, size, trabecular density, and cement volume. Vertebrae with simulated metastases generated an average maximum pressure of 39.66 kPa during cement injection versus 6.83 kPa in intact vertebrae (P < 0.05). Higher pressures were also generated in smaller vertebrae based on a power relationship (r2 = 0.71 intact, r2 = 0.43 tumor).
Percutaneous vertebroplasty produces higher intravertebral pressures in vertebrae containing a simulated lytic metastasis than in intact vertebrae. Pressures generated in the tumor specimens are sufficiently elevated to cause embolic phenomena.
一项对胸椎和腰椎进行的生物力学尸体研究，通过模拟转移瘤来量化经椎弓根椎体成形术期间椎体内压力。
比较经皮椎体成形术在有和没有模拟溶骨性转移瘤的椎体中时的椎体内压力。
经皮椎体成形术旨在为因骨质疏松或转移性疾病而变弱的椎体提供稳定性。当该手术用于治疗溶骨性椎体病变时，并发症发生率更高。报告的主要并发症是神经根病、脊髓压迫和栓塞现象。
对10个新鲜冷冻的完整尸体椎体进行测试（7个腰椎，3个胸椎），对7个椎体进行模拟溶骨性缺损测试（4个腰椎，3个胸椎）。通过用软肿瘤组织替代椎体中心的松质骨核心来制造缺损。通过单椎弓根入路以每分钟3毫升的恒定速率将Simplex P骨水泥（豪美德骨科，新泽西州马哈瓦）注入每个椎体。记录骨水泥体积、注射力和椎体后壁的椎体内压力。手术后，将椎体切片以观察骨水泥和肿瘤分布情况。
两组在年龄、大小、小梁密度和骨水泥体积方面无显著差异。在注入骨水泥期间，有模拟转移瘤的椎体平均最大压力为39.66千帕，而完整椎体为6.83千帕（P < 0.05）。基于幂关系，较小的椎体也会产生更高的压力（完整椎体r2 = 0.71，有肿瘤椎体r2 = 0.43）。
经皮椎体成形术在含有模拟溶骨性转移瘤的椎体中产生的椎体内压力高于完整椎体。肿瘤标本中产生的压力足以引发栓塞现象。
