Bone changes in the lower limbs from participation in an FES rowing exercise program implemented within two years after traumatic spinal cord injury

Abstract

Objective: To determine the effect of a functional electrical stimulation (FES) rowing program on bone mineral density (BMD) when implemented within two years after SCI. Design: Prospective. Setting: Health Care Facility. Participants: Convenience sample; four adults with recent (<2 years) traumatic, motor complete SCI (C7-T12 AIS A-B). Intervention: A 90-session FES rowing exercise program; participants attended 30-minute FES training sessions approximately three times each week for the duration of their participation. Outcome Measures: BMD in the distal femur and tibia were measured using peripheral Quantitative Computed Tomography (pQCT) at enrollment (T 0 ) and after 30 (T 1 ), 60 (T 2 ), and 90 (T 3 ) sessions. Bone stimulus was calculated for each rower at each time point using the average number of weekly loading cycles, peak foot reaction force, and bone mineral content from the previous time point. A regression analysis was used to determine the relationship between calculated bone stimulus and change in femoral trabecular BMD between time points. Results: Trabecular BMD in the femur and tibia decreased for all participants in T 0-1 , but the rate of loss slowed or reversed between T 1-2 , with little-to-no bone loss for most participants during T 2-3 . The calculated bone stimulus was significantly correlated with change in femoral trabecular BMD (P = 0.016; R 2 = 0.458). Conclusion: Consistent participation in an FES rowing program provides sufficient forces and loading cycles to reduce or reverse expected bone loss at the distal femur and tibia, at least temporarily, in some individuals within two years after SCI. Trial Registration: NCT02008149.

Timing and Modulation of Activity in the Lower Limb Muscles During Indoor Rowing: What Are the Key Muscles to Target in FES-Rowing Protocols?

“…Notwithstanding these differences, we do not see any reason to discredit the validity of our results. It should be noted we use our results to propose a collective reflection on which leg muscles to stimulate in FES-Rowing applications, hoping to optimise the health benefits of FES Rowing [3,6] and to increase its feasibility and therefore, its popularity among SCI individuals. Given our common experience that motor proficiency arises with the suppression of unnecessary muscle activity (i.e., cocontraction), shaping the stimulation of leg muscles according to the excitation of leg muscles observed for elite than novice rowers is more likely to delay fatigue development and to produce smooth kinematic profiles [16,44].…”

“…However, given that the total number of stimulation channels is often limited to four-six, distributed between muscles in both legs, our results ( Figure 3) suggest recovery could be more easily facilitated by stimulation of tibialis anterior than hamstrings. During the rowing drive phase, the decision of which muscles to stimulate is less discussable; according to previous and current results, quadriceps would seem to be the main knee extensor muscles (current results; see also [1][2][3][4][5][6]). It should be noted though that soleus was consistently activated during the drive phase, both across subjects and legs (Figures 2-4).…”

“…The greater metabolic demand resulting from the combination of electrically and voluntarily elicited contractions likely motivated the emergence of different FES protocols, in particular, the FES-indoor Rowing (henceforth FES Rowing). Notwithstanding the documented musculo-skeletal and cardiovascular benefits of FES Rowing in paraplegia (e.g., decreased loss of bone mineral density, increased aerobic capacity; [3][4][5][6]), no consensus seems to exist as per which muscles to stimulate and when. In FES-Rowing studies, the cyclic flexion-extension of the knee has been respectively achieved through stimulation of quadriceps and hamstrings [1,3,7,8]; often though, the specific quadriceps and hamstrings muscles considered for stimulation are not reported.…”

Design of the Cooperative Actuation in Hybrid Orthoses: A Theoretical Approach Based on Muscle Models

“…The use of active orthoses in combination with FES is an effective strategy to optimize the outcomes of gait rehabilitation training. Using hybrid orthosis to stimulate the lower extremity muscles has proven to evoke muscle hypertrophy, increase strength, improve cardiopulmonary fitness, and reduce fatigue during gait, even in subjects with severe spasticity (Nightingale et al, 2007; Qiu and Taylor, 2016; Deley et al, 2017; Ekelem and Goldfarb, 2018; Lambach et al, 2018). Complete recent reviews of hybrid exoskeletons can be found in Stewart et al (2017) for the upper limbs, and Anaya et al (2018) for the lower limbs.…”

Novel instrumented frame for standing exercising of users with complete spinal cord injuries

“…Using evidence from experimental results and biomechanical data 15 Lambach et al . produce an empirical measure that connects changes in BMD in people with SCI with the magnitude and frequency of bone loading forces 16 .…”