Baclofen Reduces Brain-Trauma Induced Spasticity and Dystonia

ABSTRACTS & COMMENTARY
Source: Meythaler JM, et al. Prospective assessment of continuous intrathecal infusion of baclofen for spasticity caused by acquired brain injury: A preliminary report. J Neurosurg 1997;87:415-419; Middel B, et al. Effect of intrathecal baclofen delivered by an implanted programmable pump on health related quality of life in patients with severe spasticity. J Neurol Neurosurg Psychiatry 1997;63:204-209.

Meythaler et al have previously reported a controlled, successful reduction of spasticity following spinal cord injury (Arch Phys Med Rehabil 1996;77:461-466). They now describe a similar approach to treat severe spasticity and dystonia following brain trauma. Among 11 men and one woman, 17-39 years old, nine had severe head trauma and three severe cerebral anoxia. All 12 had their injury more than six months before treatment, and all were worsening despite vigorous rehabilitation management. Muscle tone and reflexes were judged from 1 (normal) to 5 (rigid parts and/or clonic reflexes) and from 0 to 4 (> 10/hour) in spasms.

All patients received first a double-blind sequence of two lumbar intrathecal injections of either saline or saline plus 50 mcg of baclofen, delivered at least 48 hours apart. Those who improved were selected for subsequent long-term study. Preparation included the insertion of a catheter into the lumbar subarachnoid space, advancing it to between the T5 and T7 levels and connecting it to a subcutaneous programmable pump. Average dosage of baclofen amounted to 183.8 mcg/d, but the authors indicate that dosage was increased during early days of therapy when effectiveness was being most closely evaluated.

Results were favorable in the lower extremities. Based on the five-point measuring scale, motor tone decreased by about one-third of the pre-therapy level, spasms declined from an occurrence of somewhat less than one per hour to almost none, and stretch reflexes declined to almost zero. Once the devices were implanted, patients continued the treatment as outpatients. Upper extremity improvement was also statistically highly improved but to a lesser degree than that in the lower extremities. Functional activities included reductions in joint contractures in seven patients and improvements in gait and transfers in the other five. Complications were mild: five patients had headache following LP, three patients developed atelectasis, and one played with the pump sufficiently to dislodge the catheter.

Middel et al describe a different study group, consisting of patients with hypertonia, spasticity, and pain due to either multiple sclerosis or spinal cord injury. All patients received spinal catheters and subcutaneous pumps; 22 participated in an initial double-blind control, and a further 16 were directly treated with baclofen after the success of the control study. Results were evaluated at three months and slightly more than one year. Daily levels for response to baclofen ranged from 75 to 150 mcg. Complications were minimal.

By three months, improvement in spasms was small, but muscle tone and pain improved favorably (P = 0.05). Sleep, psychosocial behavior, and mental health all improved significantly. After one year of continuous infusions of baclofen, substantial improvement of pain, tone, spasms, and bodily self-care remained. "Sickness impact" notably decreased, as did systemic health. Self -stated psychosocial evaluations, however, indicated no improvement from the starting point.

COMMENTARY

These practical and well-conducted studies offer an important beginning for patients severely disabled because of pathologically tonic or spasmodic muscle activity. Enthusiasm to be sustained will depend on the duration of relief for these patients either after the baclofen catheter eventually becomes withdrawn or a semi-permanent device can be developed. Nevertheless, this kind of functional therapy should hold great interest for neurologists and encourage more of them into physical rehabilitation careers.

Apparently, patients in the Middel et al study who experienced early euphoria at three months lost it by one year. Perhaps these late disappointments may be minimized by early counselling of the realities of outcome. Allowing patients to observe videos of their pre-treatment state also might help. Furthermore, this was only a start—who can tell what future treatments may bring? —fp