Dr. Wei-Hsiu Liu, Neurosurgery Department

Mrs. Lee, a woman in her 60s, was suffering from rigidity of the lower limbs due to a stroke. She couldn't bend her knees, and her legs and body were in a "<" shape due to hip tightness. The patient was bed ridden but unable to lie down properly. It was not easy for her family to take care of her on a daily basis and critical rehabilitation could not be carried out. Mrs. Lee's son tried many different hospitals to try to manage her condition, then he found Dr. Cheng-Chiang Chang in the Physical Medicine & Rehabilitation Department of TSGH. Dr. Chang is an expert in managing strokes and peripheral nerve rehabilitation, however Mrs. Lee's spasms were too severe to be improved effectively by botulinum toxin therapy so Dr. Chang referred Mrs. Lee to Chief Wei-Hsiu Liu of the Neurosurgery Department. With the advice of Chief Liu, Mrs. Lee underwent intrathecal injection pump therapy; the first case treated by intrathecal injection pump therapy in Tri-Service General Hospital. After the surgery was completed, the family said that the spasmodic conditions of the patient's lower limbs improved significantly and she was able to lie down properly and sit up in a wheelchair. It is now also much easier for her family to take care of her. She will continue with her rehabilitation in the Rehabilitation Department. In the future, we can apply this new technique to benefit more stroke patients in Tri-Service General Hospital.

Actions applicable for managing spasms

A spasm is a kind of movement disorder that can occur due to illnesses involving the brain or spine, including multiple sclerosis, stroke, cerebral palsy, spinal injury, or brain injury, etc. A spasm is caused by an imbalance between signal inhibitions or stimulations to the spinal cord and overexcited stretch reflexes developed to increase muscle tone and involuntary actions.

Stretching, moving, and rehabilitation are the main interventions for spasm management. Oral medications usually work well but they may induce side effects like lethargy, weakness, and nausea, etc. When spasms are systemic and severe, intrathecal baclofen (ITB) can be a good treatment option.

What is intrathecal baclofen (ITB) therapy?

• ITB therapy was approved to treat severe spasms by the US FDA in 1992.
• The baclofen bump system is composed of a bump and catheter set. The neurosurgeon will inset the catheter into the intrathecal cavity between the 8th-10th thoracic vertebras, then implant it subcutaneously in the abdominal region to allow medicine to be infused into the spinal fluid through the bump. The drug injection bump system can support trace amounts of drug infusion accurately and consistently. It can also be set to provide drug infusions in different doses each hour for different requirements based on the patient's activity levels in the day and at night. The dosage of ITB would usually only be one five hundredth or thousandth of oral medication so it significantly decreases the risk of developing side effects like common lethargy and muscle weakness.

Advantages of ITB therapy

The advantages of intrathecal baclofen infusion therapy include:

• Meeting the requirements of the individual to adjust drug doses.
• A lower dosage requirement compared with oral form may reduce side effects.
• In vitro dosage control (non-invasive) therapy.

Chief Wei-Hsiu Liu reminded us that as shown in international clinical data, intrathecal baclofen therapy may cause some potential side effects and risks including dizziness (5%), weakness (0.4%), headache (0-3%), seizures (0.4%), vomiting (1.2%), numbness (1%), hypotension (1.2%), hypertension (0.4%), and even a coma, so ITB therapy cannot be used in every case and needs to be assessed carefully before implementation. The technique is not reimbursed currently and an import permit for the anticonvulsant, the baclofen injection, requires approval from the Ministry of Health Welfare every 4 to 6 months.