Del Valle M E, Harwin S F, Maestro A, Murcia A, Vega J A
Department of Morphology and Biology, University of Oviedo, Spain.
J Arthroplasty. 1998 Dec;13(8):916-22. doi: 10.1016/s0883-5403(98)90199-1.
Although long-term studies report successful results with total knee arthroplasty (TKA), performed with or without posterior cruciate ligament (PCL) retention, controversy exists as to which is preferable in regard to patient outcome and satisfaction. The possible proprioceptive role of the PCL may account for a more normal feeling of the arthroplasty. Although the PCL has been examined using various histological techniques, immunohistochemical techniques are the most sensitive for neural elements. Therefore an immunohistochemical study was designed to determine the patterns of innervation, the morphological types of the proprioceptors, and their immunohistochemical profile. During TKA, samples were obtained from 22 osteoarthritic PCLs and subjected to immunohistochemical analysis with mouse monoclonal antibodies against neurofilament protein (NFP), S100 protein (S100P), epithelial membrane antigen (EMA), and vimentin (all present in neuromechanoreceptors). Three normal PCLs from cadaveric specimens were also obtained and analyzed for comparison. Five types of sensory corpuscles were observed in both the normal and the arthritic PCLs: simple lamellar, Pacini-like, Ruffini, Krause-like, and morphologically unclassified. Their structure included a central axon, inner core, and capsule in lamellar and Pacini corpuscles and variable intracorpuscular axons and periaxonal cells in the Ruffini and Krause-like corpuscles. The immunohistochemical profile showed the central axon to have NFP immunoreactivity, periaxonal cells to have S100P and vimentin immunoreactivity, and the capsule to have EMA and vimentin immunoreactivity. Nerve fibers and free nerve endings displayed NFP and S100P immunoreactivity. The immunohistochemical profile of the PCL sensory corpuscles is almost identical to that of cutaneous sensory corpuscles. Some prior histological studies of the PCL reported Golgi-like mechanoreceptors, and others found encapsulated corpuscles but no Golgi-like structures. This report determined the innervation of the PCL by the more sensitive immunohistochemical means, revealing four major types of encapsulated mechanoreceptors. The plentiful and varied types of encapsulated mechanoreceptors found in even the arthritic PCL suggests a rich proprioceptive role. It is controversial as to whether preservation of the PCL at TKA improves postoperative proprioception. Our findings tend to support those clinical reports of improved proprioception after PCL-retaining versus PCL-substituting TKAs. The presence of many and varied types of mechanoreceptors may account for the improved stair climbing reported in patients with PCL-retaining TKA and may contribute to patient satisfaction and a more normal feeling after TKA.
尽管长期研究报告了全膝关节置换术（TKA）的成功结果，无论是否保留后交叉韧带（PCL），但在患者预后和满意度方面哪种方式更优仍存在争议。PCL可能具有的本体感觉作用或许能解释关节置换术后感觉更正常的原因。虽然已使用多种组织学技术对PCL进行了检查，但免疫组织化学技术对神经成分最为敏感。因此，设计了一项免疫组织化学研究，以确定神经支配模式、本体感受器的形态类型及其免疫组织化学特征。在TKA手术期间，从22条骨关节炎患者的PCL获取样本，并使用抗神经丝蛋白（NFP）、S100蛋白（S100P）、上皮膜抗原（EMA）和波形蛋白（均存在于神经机械感受器中）的小鼠单克隆抗体进行免疫组织化学分析。还从尸体标本中获取了3条正常PCL并进行分析以作比较。在正常和骨关节炎患者的PCL中均观察到五种类型的感觉小体：简单板层小体、帕西尼样小体、鲁菲尼小体、克劳泽样小体以及形态未分类的小体。它们的结构包括板层小体和帕西尼小体中的中央轴突、内核和被膜，以及鲁菲尼小体和克劳泽样小体中可变的小体内轴突和轴突周细胞。免疫组织化学特征显示中央轴突具有NFP免疫反应性，轴突周细胞具有S100P和波形蛋白免疫反应性，被膜具有EMA和波形蛋白免疫反应性。神经纤维和游离神经末梢显示NFP和S100P免疫反应性。PCL感觉小体的免疫组织化学特征与皮肤感觉小体几乎相同。一些先前对PCL的组织学研究报告了高尔基样机械感受器，其他研究则发现了被膜小体但未发现高尔基样结构。本报告通过更敏感的免疫组织化学方法确定了PCL的神经支配，揭示了四种主要类型的被膜机械感受器。即使在骨关节炎患者的PCL中也发现了丰富多样的被膜机械感受器类型，这表明其具有丰富的本体感觉作用。TKA时保留PCL是否能改善术后本体感觉仍存在争议。我们的研究结果倾向于支持那些关于保留PCL的TKA与置换PCL的TKA相比术后本体感觉改善的临床报告。多种类型的机械感受器的存在可能解释了保留PCL的TKA患者爬楼梯能力改善的原因，并且可能有助于提高患者满意度以及TKA术后感觉更正常。
