Intrathecal baclofen therapy for treatment of spasticity and dystonia in childhood

Spasticity is a common presentation in a wide variety of neurological disorders like cerebral palsy (CP), multiple sclerosis, and spinal cord injury. Management of spasticity involves multiple modalities such as physical and occupational therapy, oral medicines, Botulinum toxin injection, and orthopaedic and neurosurgical intervention. Intrathecal Baclofen (ITB) therapy is one neurosurgical intervention to control spasticity in CP patients. The ITB pump is implanted subcutaneously or sub-facially in the abdomen which delivers the baclofen directly to the intrathecal space via a catheter. As a result of by-passing the blood-brain-barrier, intrathecal administration of a hundredth part of the oral baclofen dose is sufficient to relieve spasticity and therefore preventing the peripheral side-effects seen with oral administration. Although the ITB delivery systems demonstrate significant effectiveness in improving spasticity, the ITB delivery system is associated with a high complication rate which could interfere with the desired effect of ITB therapy. Therefore, in a retrospective observational study we aimed to analyse the ITB complications in a large (n=222) consecutive series of patients. The complication rate in relation to the long period of follow-up (939 pump years),was found to be similar or less than those reported in literature. Dystonia, young age and presence of gastrostomy tube were significantly associated with infective complications. Catheter complications were influenced by presence of dystonia and the surgical technique, whether it was a subfascial or subcutaneous implantation. The pump is refilled by baclofen solution. The frequency of refilling is dependent on the daily dosing regime and the concentration of the aqueous solution of baclofen in the pump. Baclofen solutions are available as commercial and compounded products. An experimental controlled study was conducted to evaluate the safety of using higher concentrations of compounded baclofen in comparison to commercial baclofen. Baclofen concentration of the compounded solution was found to be less accurate than the commercial product although it was within an acceptable range from the expected value. The number of invisible particulates was significantly higher in the compounded solution than in commercial baclofen. However, no clinical complications were reported in the compounded or in the commercial baclofen groups. As patients receiving ITB therapy may have clinical benefits of reduction of the severity of spasticity, they could also have improvements in their functional status and quality of life. A survey study to evaluate changes in functional status and heath related quality of life, showed improvement in both aspects, moreover, the improvement in the health related quality of life was more significant than the change in functional status