Among patients with chronic stroke, a dynamic progressive orthotic intervention can be an effective option for increasing wrist passive range of motion while reducing resistance to passive movement, according to a recently published study.

“One of the most debilitating aspects of stroke is hemiplegia. Half of all stroke survivors report persistent hemiplegia 6 months after a stroke. Loss of arm function and fine motor skill creates dependency in activities of daily living and many necessitate assistance from caregivers or institutionalization,” the researchers wrote. “In the past several years, specialized orthotics have been designed as interventions for hypertonicity and spasticity.

“We chose to examine the effect of 12 weeks of Dynasplint (Dynasplint Systems Inc., Severna Park, Md.) use in persons with chronic stroke who are no longer receiving therapy and are long-term residents in a skilled nursing facility,” the researchers continued. “We hypothesized that tissue modification and reduction in passive movement limitations could be accomplished irrespective of the time post stroke or extent of deformity.”

Researchers applied the Dynasplint, a custom-fitted dynamic progressive wrist extension orthosis, to six residents of a nursing facility with chronic stroke. The orthosis was worn for 4 hours daily, 4 times a week for 12 weeks. Using the Modified Ashworth Scale (MAS) and the Modified Tardieu Scale of Spasticity (MTS), researchers measured wrist passive range of motion and resistance to passive movement (RTPM) weekly and after discontinuation of the orthosis. Signal analysis and electromyographical (EMG) flexor response to extensor stretching was also measured before and after orthotic interventions using maximal root mean square values and EMG burst onset time.

 

Barbara M. Daucet

According to study results, passive range of motion of the wrist increased in five of the six participants. However, these gains were lost or minimally maintained after orthotic use was discontinued. When raw data were analyzed, MTS measures showed a downward trend, suggesting larger ranges of resistance-free movement. Following intervention, researchers also found moderate effects in EMG measures, indicating increases in amount of resistive-free movement. MAS scores remained constant despite the intervention.

“The results were not particularly surprising, but interesting in that the wrist orthosis is widely used for upper extremity tissue remodeling following stroke — especially in skilled nursing settings — but there has been no empirical data, until this study, to support that the orthotic actually improves wrist mobility,” Barbara M. Doucet, OTR, PhD, assistant professor of the Department of Rehabilitation Sciences from the School of Health Professions at the University of Texas Medical Branch, told O&P Business News. “Another interesting study result is that even persons with chronic stroke, living in a skilled nursing facility, not receiving any type of therapy and exhibiting moderate joint deformity — candidates who are thought to be most resistant to improvement and motor recovery — still made positive gains with the consistent use of the orthosis.”

Although patients with chronic stroke showed improved joint range of motion and mobility with consistent use of the wrist extension orthosis, Doucet said similar studies with a larger number of participants are warranted.

“Unfortunately, RTPM and spasticity remain an intractable problem for persons with stroke and the therapists who provide care for them,” Doucet said. “Although much evidence suggests that spasticity and pathological flexor patterning in the upper extremity following stroke is a result of cortical disinhibition, the clinical tools we have currently that are practical and available for use in practice only address the problem peripherally.”

New therapies for spasticity are currently being studied, according to study researchers.

“Transcranial magnetic stimulation (TMS) is now being used as an intervention to address spasticity from the cortical vantage point. Recent evidence is suggesting that TMS may facilitate reductions in tonal abnormalities after stroke,” the researchers concluded. “Research and clinical practice continue to be incredibly divergent on the measurement, quantification and treatment of tonal abnormalities related to stroke, but innovative treatments and development of in-clinic devices with ease of use may eventually close this gap.” — by Casey Murphy

For more information:

Doucet BM. J Hand Ther. 2013;26:139-147.

Disclosure: Doucet has no relevant financial disclosures.