Toh E, Mochida J
Department of Orthopaedic Surgery, Tokai University School of Medicine, Kanagawa, Japan.
Spine (Phila Pa 1976). 1997 Apr 1;22(7):721-6. doi: 10.1097/00007632-199704010-00001.
The histologic changes in the lumbosacral nerve roots of aged rabbits because of chronic (graded) and acute compression were compared with those seen in young rabbits.
To study differences in the process of recovery from nerve compression between the aged and the young.
Clinical findings often differ between nerve compressive lesions in young and aged patients. Little has been reported on the pathologic basis of this difference.
Forty-five Japanese white rabbits were used. The cauda equina and spinal nerve root were compressed with a device specifically designed for this purpose. Nerve compression was applied to the dura mater and nerve roots after partial laminectomy. The specimens were sampled at 1 month or 3 months after acute or graded nerve compression.
An increase in small myelinated fibers, consistent with the process of regeneration, was observed by light microscopy; this difference was greater in the young group than in the aged group. Reactive degenerative changes, as seen by electron microscopy, were more often observed in the aged group than in the young group.
These findings demonstrate the suppression of regeneration and the latent fragility of the aged neural tissue. This may explain the clinical findings observed in aged patients with degenerative lumbar lesions.
将老年兔腰骶神经根因慢性（分级）和急性压迫所致的组织学变化与年轻兔的变化进行比较。
研究老年和年轻动物从神经压迫恢复过程中的差异。
年轻和老年患者神经压迫性病变的临床发现常有差异。关于这种差异的病理基础报道较少。
使用45只日本白兔。用专门为此设计的装置压迫马尾和脊神经根。在部分椎板切除术后对硬脑膜和神经根施加神经压迫。在急性或分级神经压迫后1个月或3个月采集标本。
光镜下观察到有髓小纤维增加，符合再生过程；年轻组的这种差异比老年组更大。电镜下观察到的反应性退行性改变在老年组比年轻组更常见。
这些发现表明老年神经组织再生受抑制且存在潜在脆弱性。这可能解释了老年退行性腰椎病变患者的临床发现。
