Thermal Therapy Speeds Limb Recovery After Stroke

NEW YORK (Reuters Health) - Thermal stimulation comprised of alternating application of heat and cold to the hand and wrist seems to help rehabilitate stroke survivors' paralyzed upper limbs, investigators from Taiwan report.

In what may be the first study to look at the effects of thermal therapy on stroke rehabilitation, researchers found that cycles of heat and cold significantly enhanced the sensory and motor functions in the arms and hands of stroke patients after just a few weeks of therapy.

The vast majority (85 percent) of stroke survivors experience some degree of impairment in an upper limb and recovery is often poor, Dr. Fu-Zen Shaw and associates explain in their article, to be published in the December issue of Stroke. Previous studies have shown that thermal stimulation can simultaneously activate many areas of the brain -- a process believed to help stroke patients recover function. And, compared to other treatments, it represents a low-cost, simple intervention. Thermal stimulation is common in orthopedic rehabilitation and is sometimes used to treat muscle-skeletal pain or spasticity in stroke patients.

For their study, Shaw, from National Chiao Tung University in Hsinchu, and associates administered thermal stimulation using hot packs (heated to roughly 75 degrees C) and cold packs (chilled to less than 0 degrees C) wrapped in towels to buffer the thermal conduction. Duration of direct heating and cooling stimulation was limited to 15 to 30 seconds, repeated 10 times with 30-second pauses.

Patients were encouraged to actively move their hands away from the stimulus when it became uncomfortable. The treatment was applied in 20- to 30-minute sessions five times per week for 6 weeks.

Fifteen patients in the experimental group and 14 in the control group completed the treatment protocol.

According to the team, thermal therapy was associated with significant improvement in sensation, wrist extension, and motor function, compared with the control group, with greatest change observed between weeks 4 and 6.

These results indicate that thermal stimulation is a "good, useful and convenient technique" to speed the recovery of sensory-motor function in upper limbs of stroke patients, Shaw stated.

"Although an ongoing improvement after the 6-week thermal stimulation may be expected," the investigators note, "whether the facilitation seen in the intervention period is continuous at follow-up, and what the optimal intensity is of thermal stimulation remain to be studied."

SOURCE: Stroke, December 2005.