The purpose of this research was to check the effects of the Funkquist A dorsal laminectomy in normal dogs. The technique accomplished consisted in dorsal approach to the spine; removal of T13-L1 laminae with or without vertebral bodies elevation; mantainement of the supraspinous ligament; placement of subcutaneous fat as supramedulary pad; suture of thoracolumbar fascia, subcutaneous and skin; and compressive bandage for seven days. Fourty-eight hours latter all the dogs (10) submitted to this technique showed loss of the postural reactions and paraparesis classified of moderated to serious. Hypalgesia was ascertained in five of them. Trying to discover the causes, was accomplished histologic studies of spinal cord collected 4 and 48 hours after the accomplishment of the laminectomies were conducted, however with modifications as: non-elevation of the vertebral bodies during the surgery and prevention of any type of compression spinal after the laminectomie. Examining these results was possible to conclude that the neurologic dysfunctions were originated from cord lesions caused for: elevation of the vertebral bodies during the laminectomy, possible damage of spinal vessels, destabilization of the spine and a somatory of compressive forces acting upon an uncovered spinal cord. At the necropsy of five dogs realized forty - five days latter were possible to verify: the permanence of the supraspinous ligament; that the fat grafts do not avoid the penetration of the fibrous tissue into the vertebral canal neither its adherency to the dura mater; notorious (p < 0.01) flattening of the vertebral canal and deformations of the spinal cords. With support on these results, isn't advise to furfill these surgery procedure in the thoracolumbar junction of dogs. The mantainement of the supraspinatus ligament do not perturb the realization of the laminectomy, minimize the occurrence of the aesthetics defects at the dorsal midline and can participate at the immediate postoperative cord compression.
spine; surgery of dogs; laminectomy
