Body Weight Support Treadmill Training Improves Walking in Sub-Acute and Chronic Severely Disabled Stroke Patients

Joan C. Breen MD; Barb Baker DPT, NCS Donna Snyder ACSW; Kelley Thibault PT, NCS Portsmouth Regional Hospital, Portsmouth, NH

Adapted by Mobility Research from a poster presentation

The study presented by Dr. Breen focuses on the effectiveness of body weight support treadmill training (BWSTT) on improving mobility in sub-acute and chronic stroke patients treated in a community-based rehab program. BWSTT is a neuro-rehabilitation technique that has been demonstrated effective for stroke patients in research settings. For BWSTT, the patient is partially unweighted (of his/her own body weight) and secured in a harness system held over a moving treadmill. The harness system should be able to provide varying amounts of support for the patient. Therapists are then responsible for providing trunkal support and assistance in advancing the patient's weak leg. General goals of BWSTT include the following: improvement to patient ambulation, standing balance, and endurance. Importantly, BWSTT is used with all stroke patients who cannot ambulate independently on a treadmill regardless of time since stroke, age, co-morbid conditions, or type assistive device used. At Portsmouth Regional Hospital, BWSTT is integrated into the comprehensive physical therapy program used with outpatient stroke rehab patients.

The BWSTT training protocol in this study was comprised of gait training on either the Lite Gait (Mobility Research, Tempe, AZ) or Biodex BWSTT systems. The patients were treated 1-3 days per week over an average of 13 weeks (range: 3-30). Therapy consisted of 3-5 minute walks lengthened to 20 minutes. Patients were asked to walk as fast as possible while maintaining a smooth rhythmic gait. When patients were able to walk for 20 minutes at 2 mph without sacrificing good gait patterns, body weight support would be gradually reduced. Upon therapist's assessment, the following variables were adjusted throughout therapy: percent of unweighting, assistance offered for stabilizing trunk, amount of upper extremity (UE) support, number and duration of rest periods, total walking time, assistance offered for advancing involved lower extremities (LE).

Three clinical assessments were performed in this study - a six-minute walk test, "timed up and go" (TUG), and a timed stand test. The six-minute walk test measures the distance a patient can cover in six minutes administered with or without assistance; generally 1200(+) ft is normal. The TUG test measures functional balance, asking the patient to stand up from a chair, walk 10 feet, turn around, walk back to the chair and then sit down. A normal time is under 10 seconds, higher than that is often associated with increased fall risk. The final test assesses functional LE strength by timing a patient while he/she stands and sits without using his/her hands. Generally, older, unimpaired adults perform this activity in under 10 seconds.

In this study, 34 consecutive stroke patients (25 ischemic and 9 hemorrhages) were treated with BWSTT between February 2002 and July 2006. The average age was 59 years (range: 16-81) and 11 of the patients who began treatment more than 90 days post-stroke were classified as "chronic". The results of this study were incredibly positive, with 28/29 of all and 11/11 chronic patients improving in the six-minute walk test from a pre-therapy average of 473 feet to a post-therapy average of 880 feet. Again, 28/29 and all of the chronic patients improved for the TUG test, the average dropping from 28 seconds to 14 seconds. The timed stands results showed that 27/29 of all and 10/11 chronic patients improved from an average time of 31 seconds to 17 seconds.

Most impressively, of the 11 patients who arrived in wheelchairs, 6 were discharged with no device, two each transitioned to a cane and walker, and one was discharged at wheelchair level. The 2 patients admitted using walkers were discharged with no device. Four of the 10 patients who used a cane upon admission were discharged using no device. The other 4 patients were admitted and discharged with no device. 21/29 patients achieved independent ambulation on the treadmill.

These results lead the researchers to conclude that BWSTT is effective in a community-based outpatient rehab setting. Also, severely disabled stroke patients benefit from this training method during both the sub-acute and chronic phases of recovery. Though already more than 90 days post-stroke, patients showed significant improvements in all outcome measures. Thus, patients can improve in a small number of treatment sessions and will show measurable improvements in endurance, balance, and LE strength.