Tethered Cord Syndrome

Tethered cord syndrome (TCS) is a disease that occurs at the end of the spinal cord. The end of the spinal cord normally moves back and forth as the spine flexes and extends. In this disease, there are abnormal attachments preventing this normal movement.

Clinical signs vary but often include intermittent or chronic pain, exercise intolerance, gait changes in the hind limbs, reluctance to jump or use stairs, anxiety or other behavioral problems, resentment of handling their hind end, difficulty sleeping through the night, and occasionally urinary incontinence.

Diagnosis can be difficult and involves a combination of a relevant history, clinical exam, suggestive findings on MRI, and ruling out other potential causes (through MRI, orthopedic surgery consultation, x-rays of the hips, and CSF analysis). Confirmation of tethered cord syndrome is often only made intra-operatively by identifying the tight band of tissue causing the tether.

Medical management consists of multimodal therapy aimed at controlling pain, associated fear behaviors, and urinary abnormalities. Typically this consists of short courses of anti-inflammatory steroids (prednisone) in combination with medications such as pregabalin, amantadine, and/or methocarbamol. Proin is often used to manage incontinence.

Surgical treatment involves a dorsal laminectomy (removal of a window of bone at the top of the spine) to remove the abnormal attachments and cut the ligament at the end of the spinal cord. Specific risks for this surgery include nerve root injury, which may cause transient or permanent neurologic worsening (urinary incontinence, tail paralysis, pelvic limb weakness), and an incomplete or lack of response to surgery.

Surgery is pursued in dogs with uncontrollable or recurring pain, dogs with urinary incontinence, or dogs with behavioral concerns that impact safety. While resolution of clinical signs is possible, some patients can still require ongoing medications in the long-term. Based on the studies available in dogs having undergone surgery for tethered cord syndrome, 67% of owners reported improvement or resolution in all clinical signs, 75% of the dogs with urinary incontinence showed improvement, and 100% reported improved quality of life 1-year after surgery.