Intrathecal baclofen pump for spasticity management

Spasticity is an abnormal increase in the resting muscle tone due to a brain or a spinal cord disease. It often leads to impairment of residual function in the afflicted limb along with stiffness, pain, discomfort, and limitation in the range of joint movement. It can predispose to skin breakdown, ulceration, and infection. It impedes personal hygiene and adds to caregiver burden. In addition, multiple involuntary movements can accompany spasticity including painful spasms and body jerks or shaking. The most common causes of spasticity include stroke, multiple sclerosis, brain or spinal cord injury, and cerebral palsy. Conventional treatment of spasticity includes a combination of stretching exercise, physical therapy, oral muscle relaxants, and targeted botulinum toxin injections to focal areas of spasticity.

Surgical implantation of an intrathecal baclofen pump is a newer neuromodulatory technique indicated for severe or treatment-refractory spasticity. In this technique, a catheter is surgically implanted under the coverings of the spinal cord often in the mid-back. The catheter is connected to a batteryoperated pump housed under the skin in the lower abdomen. The pump is periodically filled with liquid baclofen (a potent muscle relaxant) and can be programmed to continuously deliver baclofen directly to the spine. The delivery can follow a simple continuous mode or a flex mode incorporating additional boluses to serve individual patient needs and lifestyle. Most of the liquid baclofen gravitates in the lower part of the spine where the motor control centers of the lower extremities are located. Therefore, intrathecal baclofen usually results in a significant reduction in muscle tone and spasms of the lower extremities. Some benefit can also be achieved in the upper extremities though the benefit is often smaller compared to the lower extremities. The concentration of intrathecal baclofen needed to achieve meaningful tone reduction is much less compared to that of oral baclofen and is better tolerated by patients due to a lower rate of systemic and sedating side effects. Intrathecal baclofen pump has been studied and found beneficial in patients with post-stroke spasticity, multiple sclerosis, and traumatic central nervous system injuries. The pump can be replaced every 4 to 5 years via a simple outpatient procedure and can be connected to the existing catheter after each replacement.