Sandra L. Stevens

Influence of age on step activity patterns in children with cerebral palsy and typically developing children.

OBJECTIVE To document the influence of age on step activity patterns in children with cerebral palsy (CP) and typically developing (TD) children. DESIGN Cross-sectional. SETTING All step activity data were collected in free-living environments. PARTICIPANTS Children with CP (n=27; age, 4-18y; 22 boys, 5 girls; Gross Motor Function Classification System levels I and II) and 27 age- and sex-matched TD children were recruited through public advertisements and contacts with local clinicians. CP and TD participants were stratified into younger (<10y; n=14) and older (10-18y; n=13) age groups. INTERVENTION Daily step activity was monitored using a step activity monitor that was individually programmed to account for the gait characteristics of each participant. Step activity data were collected in 1-minute epochs during waking hours on 3 weekdays and 1 weekend day. Stored data were analyzed to yield average values of daily step activity, percentage of inactive time (0 steps) over the entire day, and percentage of total daily active time spent in low step activity (1-15 steps/min), medium step activity (16-40 steps/min), and high step activity (>40 steps/min). MAIN OUTCOME MEASURES Daily step activity, percentage of inactive time, and percentage of active time spent in low-, moderate-, and high-intensity step activity. RESULTS A significant (P<.05) interaction was observed between age (younger, older) and condition (CP, TD) for daily step activity, percentage of inactive time, and percentage of active time spent in low- and high-intensity step activity. The main effect of age was significant for each physical activity measure except for relative high-intensity step activity, and the main effect of condition was significant for all physical activity measures. Follow-up analyses (P<.025) revealed that older children with CP took fewer daily steps and displayed higher relative levels of inactivity and low-intensity activity and lower relative levels of high-intensity activity compared with older TD children. Older children with CP also exhibited lower daily step activity, demonstrated higher relative levels of inactivity and low-intensity activity, and displayed lower relative levels of moderate-intensity activity compared with younger children with CP. CONCLUSIONS Compared with younger children with CP and age- and sex-matched TD youth, older youth with CP generally displayed step activity patterns typified by lower levels of physical activity and a greater degree of inactivity. These findings highlight the need to provide multiple opportunities for adolescents with CP to engage in a variety of physical activities that are appropriate to their needs, abilities, and preferences and that can aid in maintaining functional mobility, health, and quality of life.

Leg Strength, Preferred Walking Speed, and Daily Step Activity in Adults With Incomplete Spinal Cord Injuries

BACKGROUND The reduction in physical activity that accompanies spinal cord injury (SCI) contributes to the development of secondary health concerns. Research has explored potential strategies to enhance the recovery of walking and lessen the impact of physical disability following SCI, but further work is needed to identify determinants of community walking activity in this population. OBJECTIVES To quantify relationships among lower extremity strength (LES), preferred walking speed (PWS), and daily step activity (DSA) in adults with incomplete SCI (iSCI) and determine the extent to which LES and PWS predict DSA in persons with iSCI. METHODS Participants were 21 adults (age range, 21 to 62 years; AIS levels C and D) with iSCI. Maximal values of hip abduction, flexion, and extension, knee flexion and extension, and ankle dorsiflexion and plantar flexion were measured using handheld dynamometry and were summed to determine LES. PWS was calculated using a photoelectric cell-based timing system, and participants were fitted with activity monitors to measure DSA in a natural setting. RESULTS Statistically significant (P <; .05) correlations of moderate to high magnitude (.74 to .87) were observed among LES, PWS, and DSA. Multiple regression analysis revealed that LES and PWS accounted for 83% (adjusted R2) of the variation in DSA (P <; .001). CONCLUSION A significant proportion of the explained variance in DSA can be predicted from knowledge of LES and PWS in adults with iSCI. These findings suggest that future efforts to improve community walking behavior following SCI should be directed toward increasing LES and PWS.

Heart Rate Response During Underwater Treadmill Training in Adults with Incomplete Spinal Cord Injury

BACKGROUND Walking on a submerged treadmill can improve mobility in persons displaying lower limb muscle weakness and balance deficits. Little is known, however, regarding the effect of water treadmill exercise on cardiac performance in persons with incomplete spinal cord injury (iSCI). OBJECTIVE To assess heart rate response during underwater treadmill training (UTT) in adults with iSCI. METHODS Seven males and 4 females with iSCI (age = 48 ± 13 years; 5 ± 8 years after injury) completed 8 weeks of UTT (3 sessions per week; 3 walks per session) incorporating individually determined walking speeds, personalized levels of body weight unloading, and gradual, alternating increases in speed and duration. Heart rate was monitored during the last 15 seconds of the final 2 minutes of each walk. RESULTS Over the course of 3 biweekly periods in which walking speed remained constant, heart rate fell by 7% (7 ± 1 b•min(-1); P < .001) in weeks 2 and 3, 14% (17 ± 6 b•min(-1); P < .001) in weeks 4 and 5, and 17% (21 ± 11 b•min(-1); P < .001) in weeks 6 and 7. CONCLUSION In adults with iSCI, progressively greater absolute and relative reductions in submaximal exercise heart rate occurred after 2 months of UTT featuring a systematic increase in training volume.

Strength and Step Activity After Eccentric Resistance Training in Those With Incomplete Spinal Cord Injuries

Background: Individuals with spinal cord injuries (SCIs) often experience general weakness in the lower extremities that undermines daily step activity. Objective: To investigate the efficacy of eccentrically biased resistance training on lower extremity strength and physical activity of individuals with spinal injuries. Methods: Individuals with long-standing incomplete SCIs (N = 11) capable of completing a 10-meter walk assessment were included. All participants who completed the familiarization period finished the training. Individuals trained two times per week for 12 weeks on a lower body eccentric resistance training machine. It was hypothesized that the outcome variables (eccentric strength, isometric strength, and daily step physical activity) would improve as a result of the training intervention. Results: Eccentric strength [F(1.27, 12.71) = 8.42, MSE = 1738.35, H-F p = .009] and isometric strength [F(1.97, 19.77) = 7.10, MSE = 11.29, H-F p = .005] improved as a result of the training while daily step activity remained unchanged [F(2.00, 18.00) = 2.73, MSE = 216,836.78, H-F p = .092]. Conclusions: Eccentric resistance training improves eccentric and isometric strength. These physiological adaptations may translate to improved gait mechanics, but further study is required to identify this potential crossover effect.

Ambulation and physical function after eccentric resistance training in adults with incomplete spinal cord injury: A feasibility study

Background: Strengthening the lower extremities has shown to positively influence walking mechanics in those with neurological deficiencies. Eccentric resistance training (ERT) is a potent stimulus for the development of muscular strength with low metabolic demand. Thereby, ERT may benefit those with incomplete spinal cord injuries (iSCI) seeking to improve ambulatory capacity. Design: This study was aimed to determine the effect of ERT on walking speed, mobility, independence, and at home function following iSCI. Methods: Individuals with longstanding iSCI trained twice a week for 12 weeks on an eccentrically biased recumbent stepper. Outcome measures: Walking speed (10 meter walk test; 10MWT), mobility (timed up and go), independence (Walking Index for Spinal Cord Injury; WISCI), and at home function (Spinal Cord Independence Measure; SCIM) were assessed at baseline, after 6 weeks, and after 12 weeks of ERT. Results: There were improvements in walking mobility (158.36 + 165.84 seconds to 56.31 + 42.42 seconds, P = .034, d = 0.62), speed (0.34 + 0.42  m/s to 0.43 + 0.50  m/s, P = .005, d = .23), and independence (8 + 7 to 13 + 7, P = .004, d = .73) after 12 weeks of ERT. At home function remained unchanged (22 + 10 to 24 + 10, P = .10, d = .12). Conclusions: Improving lower extremity strength translated to walking performance and independence in those with iSCI. Additionally, ERT may diminish therapist burden in programs designed to improve ambulatory capacity or strength in those with iSCI.

Underwater Treadmill Training for a Greenstick Fracture in a Collegiate Softball Player: A Case Report

A 19-year-old collegiate softball player collided with a fence while trying to catch a fly ball, resulting in a greenstick fibular fracture. Underwater treadmill training (UTT) was used as a modality to supplement traditional physical therapy (TPT). Active range of motion (AROM) in all directions for the knee, hip, and ankle, girth of the thigh and lower leg, static balance, and 6-Minute Walk Test (6MWT) distance were assessed pre- and postintervention. The addition of UTT to TPT led to postintervention increases in AROM, static balance, and limb girth, with no additional discomfort to the participant.

The Gait Restorative Effects of Robotic-Assisted Gait Training for Individuals with Neurodegenerative Disease: A Review

Background : Neurodegenerative diseases and disorders present with a wide range of clinical and neuropathological symptoms caused by progressive neuronal dysfunction and eventual neuronal death. As individuals with neurodegenerative diseases experience gradual sensory, motor, and cognitive debilitation, the maintenance and recovery of a functional gait holds physiological, psychological, and financial importance. Developments in robotically-aided therapies are becoming more commonly used as a therapeutic tool for the improvement of gait characteristics and overall motor function for individuals with various gait impairments. To date, studies examining the effects of robotic-assisted gait training (RAGT) as treatment for neurodegenerative diseases, have only been performed in individuals with multiple sclerosis (MS), Parkinson’s disease (PD), and progressive supranuclear palsy (PSP). Purpose : The purpose of this review is to summarize and show trends to the efficacy of RAGT as a gait restorative and preservative modality for individuals with these neurodegenerative diseases including MS, PD, and PSP. Results : The overall trends reported by these reviewed studies show that RAGT may be an effective therapy for producing significant improvements in multiple gait characteristics including balance, walking speed, endurance, leg strength, gait safety, and motor function for individuals with neurodegenerative disease. Conclusion : The studies in this review suggest that RAGT therapies may be an effective substitute for, or addition to, present conventional therapies for individuals with neurodegenerative disease, however the long-term effects of this therapy are still not known for these individuals.

Robotic-Assisted Gait Training Therapies for Pediatric Cerebral Palsy: A Review

Background : Children and adolescents with CP experience many types of disability and functional impairment that effect the gait cycle. New robotic gait therapies adapted to pediatric patients provide a safe, highly repetitive, and task-specific therapeutic venue for the rehabilitation and elicitation of a more natural walking gait. While the use of robotic-assisted gait training (RAGT) is a relatively novel therapeutic approach to gait therapy, several studies have examined the efficacy of this therapeutic modality in pediatric patients with CP. Purpose : The purpose of this review is to examine the trends in the therapeutic efficacy of utilizing RAGT therapy as a gait restorative modality for children with CP. Results : The present studies show that RAGT therapy may provide multiple therapeutic benefits to children with CP, including statistically significant improvements in gross motor function and multiple gait characteristics. Also, RAGT therapy may be a safe and favorable complement to current physiotherapy regimens. Conclusion : As various degrees of functional improvement are a noticeable trend among all presented studies, further study in this therapeutic technique is warranted, and implementation of similar therapeutic protocol may be valuable to a rehabilitation care plan. The highly repetitive and task-specific nature of RAGT may provide a valuable paradigm for children with CP whom have never learned a normal gait pattern.