Cervical Spine Locking Plate Fixation for Treatment of Cervical Spondylotic Myelopathy in Large Breed Dogs

Objective To describe indirect decompression by means of cervical spine locking plate (CSLP) fixation with vertebral distraction, discectomy, and cancellous block bone grafting in large breed dogs with single caudal cervical dynamic spondylotic lesions diagnosed by myelography with linear traction to the cervical spine, and contrast-enhanced computed tomography. Study Design Prospective clinical study. Animals Dogs (n=12) with caudal cervical spondylotic myelopathy because of a single dynamic, traction-responsive lesion. Methods Single, traction-responsive, caudal cervical spondylotic lesions were treated by vertebral distraction, discectomy, cancellous block bone grafting, and CSLP fixation. Follow-up was obtained by sequential recheck examination by the author or referring veterinarian or by telephone inquiries. Results Ten dogs had neurologic improvement after surgery. Indirect decompression by maintained distraction with cancellous block grafting and CSLP fixation was readily accomplished with less risk of blood loss or iatrogenic spinal cord injury than that associated with direct (ventral) decompression. There were no complications of graft intrusion, extrusion or subsidence, implant loosening, foraminal impingement, or end-plate failure. Two dogs that had satisfactory short-term recoveries developed clinical signs associated with adjacent segment disease and were euthanatized. At long-term follow-up, 8 dogs had satisfactory function, either a normal gait or one with slight to moderate proprioceptive deficits. Conclusions CSLP fixation with cancellous block interbody grafting is an effective and perhaps safer method of treating single-level, traction-responsive cervical spondylosis in large breed dogs. Clinical Relevance CSLP fixation with interbody bone grafting is a viable alternative to other techniques for treatment of single-level, traction-responsive cervical spondylosis.