A hemilaminectomy is the most common surgical approach in the thoracolumbar spine. The approach is less commonly used in the cervical spine. The surgical approach for a hemilaminectomy is from the top side of the dog or cat. Once the spinal column is reached a portion (lamina) of the vertebrae is removed from the side. This allows for removal of disc that has herniated off to one side or the other or removal of a tumor or cyst that may be located on one side of the spinal cord. This approach also allows direct access to the disc that lies underneath the spinal cord. It allows for greater access to the spinal canal compared to a ventral slot and allows visualization beneath the spinal cord which is difficult to obtain during a dorsal laminectomy. Once the portion of the vertebrae is removed during a hemilaminectomy the herniated or ruptured disc material is then removed with small instruments. The combination of the hemilaminectomy approach and disc material removal alleviates compression or pinching the spinal cord allowing further spinal cord healing to take place. During the hemilaminectomy procedure the disc is not replaced. Fenestration of the affected disc and sometimes the nearby discs may be done depending on the clinical scenario and neurosurgeonâ€™s preference. Potential complications from hemilaminectomy include trauma to the spinal cord, hemorrhage, infection and instability. The prognosis with the hemilaminectomy procedure is often good, but depends on the pre-surgical condition of the pet. Dogs and cats with acute disc herniation that have the ability to feel their toes at the time of surgery typically do quite well. The success rate with surgery is less for dogs without sensation of their toes, chronic spinal cord compression and multiple compressive sites. Recovery time is variable with return to ambulation typically within weeks to months. Strict rest/confinement is recommended for about 1 month post-surgery with gradual increase in activity thereafter. During confinement a well-padded surface is recommended to prevent bed sores. It is important to ensure that your pet is urinating regularly post operatively. Urinary tract infections are common in dogs with spinal cord injury and should be monitored for. Rehabilitation therapy can speed recovery.