Sjollema B E, Venker-van Haagen A J, van Sluijs F J, Hartman F, Goedegebuure S A
Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, State University of Utrecht, The Netherlands.
Am J Vet Res. 1993 Jan;54(1):185-90.
The innervation of the levator ani and coccygeal muscles and the external anal sphincter was studied by anatomic dissection in 6 clinically normal male dogs and by electrical stimulation in 5 clinically normal male dogs. Variations in innervation occasionally were found that were comparable to those reported in previous studies. Electromyographic recordings were made from the levator ani and coccygeal muscles and from the anal sphincter in 40 dogs during perineal hernia repair. Spontaneous potentials of 4 types were found in 35 dogs: fibrillation potentials, positive sharp waves, complex repetitive discharges, and fasciculations. Biopsy specimens of the cranial part of the levator ani muscle were taken in 12 dogs during perineal hernia repair. Histologic examination revealed atrophy in 7 specimens. Spontaneous potentials were recorded from all muscles with histologic evidence of atrophy. All examinations of the levator ani muscle concerned the cranial part of this muscle, because the caudal part was absent in all 40 dogs. From combined results of electromyography and histologic examination, it was concluded that atrophy of the muscles of the pelvic diaphragm, which develops in some dogs with perineal hernia, is likely to be of neurogenic origin. Nerve damage is localized in the sacral plexus proximal to the muscular branches of the pudendal nerve or in the muscular branches separately.
通过对6只临床正常的雄性犬进行解剖和对5只临床正常的雄性犬进行电刺激，研究了肛提肌、尾骨肌和肛门外括约肌的神经支配情况。偶尔会发现神经支配的变异，这些变异与先前研究报道的情况相当。在40只犬进行会阴疝修补手术期间，对肛提肌、尾骨肌和肛门括约肌进行了肌电图记录。在35只犬中发现了4种类型的自发电位：纤颤电位、正锐波、复合重复放电和束颤。在12只犬进行会阴疝修补手术期间，采集了肛提肌头部的活检标本。组织学检查显示7个标本存在萎缩。对所有有组织学萎缩证据的肌肉都记录到了自发电位。所有对肛提肌的检查都涉及该肌肉的头部，因为在所有40只犬中都没有尾部。根据肌电图和组织学检查的综合结果，得出结论：一些患有会阴疝的犬出现的盆底肌萎缩可能源于神经源性。神经损伤定位在阴部神经肌肉分支近端的骶丛或分别在肌肉分支中。
