Spinal cord injuries (SCI) are often associated with paralysis of peripheral body parts including limbs, neck, and the back. People with SCIs are highly immobile and for this reason, they are exposed to very many risks such as the development of heart diseases, diabetes, and obesity.
Once these diseases develop, they can cause premature death. For this reason, various devices have been developed in a bid to counter the development of such problems. These devices normally use a robotic mechanism to enable patients achieve near normal mobility of various body parts. In addition, the devices enable patients to move various body muscles. These robotics assisted devices confer specific advantages to patients with SCI. The paper explains how such devices accomplish this goal.
When applied during the initial phases of SCI, robotic-assisted tilt-table therapy (RATTT) enables the patient to do cardiopulmonary exercise. In particular, it is most beneficial to the SCI patient during the acute phase of spinal injury, before the patient can withstand orthostatic exercise and before commencement of the customary exercise (Craven, Gollee, Coupaud, Purcell, & Allan, 2013).
When used to enable head uplift exercises, passive robotic-assisted stepping increases ventilation, albeit in small quantities. The use of this device also increases oxygen uptake, heart rate, and minimal ventilation in an SCI patient.
When used in conjunction with RATTT, functional electrical stimulation (FES) facilitates the cardiopulmonary and ventilator response of motor-incomplete in SCI patients. FES-assisted RATTT results in a considerable increase in cardiopulmonary and ventilator functions for patients, especially while participating in volitional therapy (Craven, et al., 2013).
Another benefit of RATTT is that it facilitates oxygen uptake and respiratory exchange ratio (RER). Both respiratory exchange ratio and oxygen uptake are indicative of the amount of stress that the cardiopulmonary system has to endure while the patient is exercising. However, the SCI patients cannot attain normal oxygen uptake owing to its inability to recruit all the involved muscles. In a normal person, normal oxygen uptake ranges between 34 and 44 mL/kg/min.
Volitional participation of SCI patients in RATTT helps them achieve the upper limit of the expected oxygen uptake. Thus, regular volitional participation in RATTT may be essential in sustaining cardiopulmonary fitness of these patients. Oxygen uptake in people is usually related to the demand imposed by the various muscles of the body.
Consequently, increased activity of the body muscles lead to increased oxygen uptake, which is necessary to achieve positive cardiopulmonary responses. The condition of SCI often causes decline in muscles because of inactivity. This decline can be overcome by continued FES-assisted RATTT training. Consequently, an improved cardiopulmonary response is attained.
Another benefit of robotic assisted device relates to orthostatic hypotension in the initial stages of SCI. Due to orthostatic hypotension, the patient may find it hard to exercise. A chronic orthostatic hypotension can slow early mobilization and engagement in rehabilitation activities intended to improve the quality of life of the patient.
Vasodilatation, which underlies hypotension, results in the accumulation of blood in the periphery. This condition compromises venous return and decreases cardiac output. Tilt-table exercises facilitated by robotics seem to address fluctuation in blood pressure.
Robotic-assisted tilt-table therapy is useful in the treatment of orthostatic hypotension. This results in increased orthostatic tolerance that is attributed to inclined peripheral resistance generated through FES stimulation of muscle mobility. RATTT maintains orthostatic stability of SCI patients because it facilitates passive movement of the legs.
The pumping effects of the lower limbs associated with RATTT mimics skeletal muscle pump. To offset orthostatic instability, increased peripheral resistance to gravitational accumulation of blood is necessary. Craven et al., (2013) assert that when combined with FES, RATTT increases orthostatic tolerance more than when used separately.
Over and above increasing orhostatic resistance, RATTT also plays a crucial role as SCI patients can use it as a necessary exercise tool. Starting the process of rehabilitation as promptly as possible may reduce deficiencies in aerobic fitness caused by inactivity. RATTT facilitates the provision of a concrete training stimulus to synergize traditional physiotherapy practices. In this regard, RATTT increases orthostatic tolerance and alleviates a decrease in aerobic fitness.
RATTT is beneficial for SCI patients as volitional efforts of the SCI patients during RATTT increase cardiopulmonary and ventilator functions. However, FES mediates these effects. Training of SCI patients with RATTT enhances cardiopulmonary and ventilator fitness in motor-incomplete SCI.
When combined with FES, it minimizes decline in fitness in those with complete-motor SCI (Craven et al., 2013). Thus, the use of robotic-assisted devices in managing patients with spinal cord injury is recommended as it lengthens the lifespan of SCI patients and improves the quality of life, albeit at a less statistically significant level.
Reference
Craven, C. T., Gollee, H., Coupaud, S., Purcell, M. A., & Allan, D. B. (2013). Investigation of Robotic-assisted Tilt-table Therapy for Early-stage Spinal Cord Injury Rehabilitation. JRRD , 50 (3), 367-378.