Benefits of therapy fail to trickle down to frustrated SCI patients
By: Jordana Bieze Foster


Even as researchers discover new ways in which spinal cord injury patients can benefit from exercise therapy, other research suggests that even motivated SCI patients feel their ability to exercise is limited by lack of access to equipment and lack of interest on the part of practitioners.

At the annual meeting of the American College of Sports Medicine in June, an international panel of experts on SCI rehabilitation discussed recent findings from the medical literature highlighting the importance of exercise in the SCI population. Although the primary focus is on the use of exercise therapy to prevent musculoskeletal and physiological complications related to disuse, an additional motivating factor is that fitter patients will be more likely to benefit from new rehabilitation techniques as they emerge.

Highlighted in the symposium were the results of two studies on plantar flexor electrical stimulation published this spring by researchers from the University of Iowa. In a study published in the April issue of the Journal of Neurophysiology, two years of unilateral electrical stimulation resulted in significantly less muscle deterioration in the trained limb than the contralateral limb (see table). A study published in the March 1 issue of Spine found that after three years of the same therapy, tibial bone mineral density declined by 10% in the trained limb and 25% in the untrained limb.

Notably, the training was initiated early-within six weeks of injury in the Neurophysiology study and within 18 weeks of injury in the Spine study. The positive outcomes underscore the benefits of early intervention that have been suggested by previous studies.

In addition, preliminary results of a prospective Dutch study suggest that the benefits of exercise therapy extend even beyond the rehabilitation period. In a collaborative effort involving eight rehabilitation centers and five research centers, investigators have found that power output and upper body muscle strength increased greatly in the first three months of rehabilitation, but also continued to increase when measured at the end of rehabilitation and one year later.

Lead researcher Lucas H. van der Woude, PhD, who presented the findings at the ACSM meeting, called the results "promising but unexpected."

"Is this improvement optimal? I cannot answer that question at this stage," said van der Woude, an associate professor of kinesiology at Vrije Universitat in Amsterdam.

Van der Woude and others have noted the long duration of SCI rehab in the Netherlands (reported means of 154 to 273 days), particularly compared to the U.S. (reported means as short as 60 days). It may not be surprising, then, that 22 SCI patients interviewed by California State University Los Angeles researchers reported feeling rushed through the rehabilitation process-just one of many patient frustrations identified through qualitative analysis and presented at the ACSM meeting by Tamar Z. Semerjian, PhD, an assistant professor of kinesiology.

"I think it's their caseload," Semerjian quoted one patient as saying. "Their goal is to do the best that they can do, not the best that you can do."

Lack of access to exercise equipment was another common theme.

"You can't just call up a gym and ask to be enrolled in the quadriplegic or paraplegic exercise program," Semerjian quoted another patient as saying.

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Practitioners seek gold standard for gait recovery after spinal cord injury
Body-weight supported treadmill training is no longer the only option for SCI patients.
By: Charlie Kupperman


Body-weight supported treadmill training (BWSTT) has been the gold standard for gait rehabilitation after an incomplete spinal cord injury-until February.

Everything changed when researchers from the University of California, Los Angeles, published the long-awaited results of a study on BWSTT after acute incomplete spinal cord injury (SCI) in Neurology that month.

The single-blinded, multicenter, randomized clinical trial of 146 patients compared BWSTT with over-ground training. Investigators had expected patients receiving BWSTT to achieve better outcomes than the control group. But in fact, the research showed no significant differences after six months for assessments such as the functional independent measure for locomotion (FIM-L) or walking speed and distance. All subjects received 12 weeks of intervention.

This disappointing verdict applies only to the effectiveness of BWSTT immediately after acute incomplete SCI, however, said lead author Bruce Dobkin, MD, a professor of neurology with the UCLA Neurologic Rehabilitation and Research Program at Reed Neurologic Research Center. More research is needed to determine whether BWSTT is more effective than other training for chronic SCI patients, Dobkin said.

Patient injuries were graded on the American Spinal Injury Association (ASIA) Impairment Scale from B (incomplete with some sensory function but no motor function below the injury) to D (incomplete with some motor function below the injury). The biggest surprise was that an unexpectedly high percentage of ASIA C patients achieved functional walking speeds, whether they received BWSTT or over-ground training. Researchers speculated that the emphasis on task-oriented therapy might have helped these patients especially.

Before this, the natural history of recovery in ASIA C patients had not been well characterized, according to Dobkin. This study has defined the best outcomes for ASIA C patients.

"Any intervention that allows patients to make use of their increasing motor control in the weeks after SCI ought to lead to gains," he said.

What's next for BWSTT?

As Dobkin points out, this study didn't address BWSTT for patients with chronic SCI. In fact, some other recent studies provide hope that BWSTT may still be useful for patients whose injuries are chronic. Also, the study argues for more trials of BWSTT, specifically in ASIA B patients who have no motor control eight weeks after SCI and in ASIA C patients who still can't walk four to six months after SCI. The Dobkin study also mentions that BWSTT may be helpful when used in combination with functional electrical stimulation or robotic assistive devices for chronic ASIA C patients who cannot walk.

Another point Dobkin and colleagues makes is that at least some of BWSTT's value may be that it is less tiring and safer than conventional physical therapy for the therapists, particularly when working with ASIA A and B patients. A recent review paper, published in the February issue of Physical Medicine and Rehabilitation Clinics of North America, suggests another possible intervention: robotic orthoses that may improve patients' rehabilitation by allowing increased stepping practice while protecting therapists by decreasing the effort they must exert (see "Power AFOs promote muscle activity, reduce therapist load," June, page 13).

Mirrors without smoke

Montreal researcher Alain Leroux, PhD, an associate professor of exercise science at Concordia University, hopes that combining BWSTT combined with mirrors could benefit some chronic SCI patients with forward-leaning posture, based on the results of a study he led.

In a 2006 study, Leroux and colleagues studied eight incomplete SCI patients walking on a treadmill at five different grades. Using four high-resolution cameras, they found that their subjects were unable to adapt their body orientation to the inclination of the support surface and walked with greater forward tilt of both the trunk and pelvic segments when walking on a level surface or an incline. The study was published in Clinical Neurophysiology in June. The downhill incline was particularly difficult for these subjects.

The researchers concluded that deficits in their lower extremities caused instability for which the forward-bending posture adopted by SCI subjects was compensating. This was exacerbated by regular use of ambulatory assistance devices. They speculated that the forward-bending posture is adapted for uphill walking but inadequate for downhill walking and could lead to a loss of balance or falls.

"I strongly believe that a training protocol involving the BWSTT with a mirror in front plus on the sides of the treadmill would help SCI subjects to realign their trunk posture appropriately," Leroux said. "We would have to start the training with level ground and progress to the downhill conditions."

The BWSTT will reduce slightly the weight supported by the patient and provide subjects with better stability to face the different treadmill conditions, he said.

It is Leroux's belief that patients would show a more upright posture during walking, after a few weeks of BWSTT training with mirrors three times per week. He also thinks they would relearn how to adapt to slope walking. He does not speculate on whether patients will retain any benefits in the absence of body-weight support, or whether these skills could transfer to over-ground walking.

A 1999 study by the same team published in the June issue of Experimental Brain Research, found that SCI patients didn't adapt their vastus lateralis, soleus, and medial gastrocnemius muscles to compensate for an uphill gradient, as normal subjects did. The researchers speculated that SCI patients use different strategies to adjust to an uphill walk.

These findings could be significant for clinicians developing gait rehabilitation programs for incomplete SCI patients, according to Leroux. The effects of BWSTT on trunk posture in incomplete SCI patients is an area that should be studied, he said.

Alternatives to BWSTT

Approaches to chronic incomplete SCI that don't include BWSTT are showing promise as well. Robotic orthoses are one such option; functional electrical stimulation is another. One study found that FES improved gait in five patients with chronic incomplete SCI. The subjects wore a new multichannel neuroprosthesis for walking, and researchers measured walking speed, step frequency, and average stride length. The paper was published in the June issue of Spinal Cord.

Increases in both stride length and stride frequency led to significantly faster walking speeds for four of the five patients. The fifth subject was able to walk with fewer orthoses and assistive devices. At follow-up several weeks after treatment, two of the subjects were walking more slowly than at the end of the trial, but still much faster than at baseline.

The convenience sample study included no control group, according to lead author Timothy A. Thrasher, a postdoctoral researcher at the Institute of Biomaterials and Biomedical Engineering at the University of Toronto. He and his colleagues are planning a randomized trial with a control group walking with orthoses and assistive devices but without FES, which will conclude at the end of 2007.

The fact that subjects continued to walk more quickly several weeks after they stopped receiving FES is probably due to a combination of improvements in both muscle conditioning and neurological organization, Thrasher said. He believes improved neurological organization is the most important factor. His team measured gait patterns in two of the patients and found their gait had improved in terms of both symmetry and EMG timing.

As well as robotic orthoses, the review mentioned earlier suggested that improved orthotic technologies and rehabilitation techniques could help incomplete SCI patients with or without other therapies. Though such patients may have some lower extremity muscle control, a conventional brace may not provide them with enough support for muscle control, said author Marmaduke Loke, CPO, a clinician with Dynamic Bracing Solutions in San Diego.

A triplanar orthosis has provided enough stability to help some incomplete SCI patients to stop using a wheelchair, Loke said.

Although incomplete SCI patients are likely to require orthotic support for the anterior calf and other lower extremity injury patients are likely to require such support for the posterior calf, orthotic interventions can help both groups, according to Loke.

"A paralyzed limb is a paralyzed limb," he said.

He argues that limited range of motion affects gait more than muscle weakness in SCI patients.

Loke feels it's important that each orthotic intervention be customized to a particular SCI patient's condition. Patients may fall forward or backward, or may have a buckling knee or a falling ankle. The clinician should look at each limb individually, and look for factors such as spasticity or tone, he said. Loke also believes clinicians should be trained in fitting incomplete SCI patients with orthoses that provide stability from the foot upwards, in all three dimensions.

Once a clinician has assessed an SCI patient's normal range of motion, he or she can align the limbs with an orthosis more efficiently, he said.

The National Institutes of Health has performed some preliminary studies, but more study of next-generation orthoses is needed to demonstrate their effectiveness in helping incomplete SCI patients to ambulate independently, Loke said.

Charlie Kupperman is a freelance writer based in San Francisco.

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Table. American Spinal Injury Association (ASIA) Impairment Scale

A = Complete: No motor or sensory function is preserved in sacral segments S4-S5.

B = Sensory incomplete: Sensation but no motor function is preserved below the neurological level of injury, including sacral segments S4-S5.

C = Motor incomplete: Motor function, with a muscle strength grade less than 3*, is preserved in more than half the muscles below the level of injury. Sensory function is present below the neurological level and includes sacral segments S4-S5.

D = Motor incomplete: Motor function is preserved below the level of injury and more than half of key muscles below the neurological level have a muscle strength grade of 3 or more. Sensory function is present below the neurological level and includes sacral segments S4-S5.

* 3 = Capable of movement against gravity

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Sources: www.sci-info-pages.com/levels.html and http://www.nrhhealthtown.com/healtht...ification.aspx