The studies reviewed here suggest that facilitating the practice of walking during rehabilitation can enhance the recovery of functional ambulation in incomplete SCI. Although specific treatment parameters that depend on the injury location, severity, and chronicity remain to be elucidated, there exists some evidence to help guide the clinical decision-making process. Task-oriented gait retraining with partial body weight support, whether provided by a treadmill and partial BWS or overground with assistive devices, appears to be more beneficial when applied sooner rather than later after the onset of injury in people with motor-incomplete lesions. Where resources permit, therapists may use a body-weight support system combined with a treadmill and manual assistance from additional personnel to implement task-oriented gait training. However, there is increasing evidence that equivalent outcomes can be obtained independent of the specific gait retraining strategy (Dobkin et al. 2006; Field-Fote et al. 2005; Field-Fote & Roach, 2011), with intensity of the therapeutic approach a key, albeit not fully understood factor. Preliminary evidence suggests that gait training strategies may also be potentiated by nutrient supplements (Nash et al. 2007) or resistance training of specific muscles (Gregory et al. 2007).
For individuals with more chronic spinal lesions and who have recovered some walking, FES may provide additional gains in functional ambulation. When resources are available, more complex FES systems, with or without bracing, may be used to provide support of upright mobility in individuals with complete paraplegia. Further evidence is required to determine whether combination therapies offer significant advantages over any given approach alone. Future studies should also examine the role of falls risk and history in ambulatory performance following SCI. Early evidence suggests that the more active a person is, the less likely that they will experience a fall (Brotherton et al. 2007). Finally, although this review has focused on functional ambulation outcomes following various rehabilitation strategies, we must also keep in mind the additional health benefits (e.g. improved cardiovascular or bone health) of performing gait exercises.
There is level 1b evidence (Harvey et al. 2010) that PES-assisted exercise may increase voluntary muscle strength, but the increase may not have a clinically important treatment effect.
There is level 2 evidence (Baldi et al. 1998) that PES-assisted isometric exercise reduces the degree of lower limb muscle atrophy in individuals with recent (~10 weeks post-injury) motor complete SCI, but not to the same extent as a comparable program of FES-assisted cycling exercise.
There is level 4 evidence (Sabatier et al. 2006) that PES-assisted exercise may partially reverse the lower limb muscle atrophy found in individuals with long-standing (>1 year post-injury) motor complete SCI.
There is level 2 evidence (Shields and Dudley-Javoroski 2006) that a program of PES-assisted exercise increases stimulated lower limb muscle torque and muscular endurance.
There is level 2 evidence (Baldi et al. 1998) that FES-assisted cycling exercise prevents and reverses lower limb muscle atrophy in individuals with recent (~10 weeks post-injury) motor complete SCI and to a greater extent than PES.
There is level 4 evidence (Scremin et al. 1999; Crameri et al. 2002) that FES may partially reverse the lower limb muscle atrophy found in individuals with long-standing (>1 year post-injury) motor complete SCI.
There is level 4 evidence (Gerrits et al. 2000) that FES-assisted cycle exercise may increase lower limb muscular endurance.
There is level 2 (Alcobendas-Maestro et al. 2012) and level 3 evidence (Wernig et al. 1995) using historical controls that BWSTT is effective in improving ambulatory function. However, two level 2 RCTs (Dobkin et al. 2006; Hornby et al. 2005a) demonstrates that BWSTT has equivalent effects to conventional rehabilitation consisting of an equivalent amount of overground mobility practice for gait outcomes in acute/sub-acute SCI.
There is level 1b evidence from 1 RCT (Field-Fote & Roach 2011) that different strategies for implementing body weight support gait retraining all yield improved ambulatory outcomes in people with chronic, incomplete SCI, except for robotic assisted treadmill training which showed little change in walking speed. It is recommended that therapists may choose a body weight support gait retraining strategy based on available resources (Field-Fote & Roach 2011).
There is level 4 evidence from pre-test/post-test studies (Behrman et al. 2012; Buehner et al. 2012; Harkema et al. 2012; Lorenz et al. 2012; Winchester et al. 2009; Hicks et al. 2005; Wirz et al. 2005; Thomas and Gorassini 2005; Protas et al. 2001; Wernig et al. 1998) that BWSTT is effective for improving ambulatory function in people with chronic, incomplete SCI.
There is level 1 evidence (Walker and Harris 1993), limited by a small sample size, that GM-1 ganglioside combined with physical therapy improves walking ability in chronic incomplete SCI patients. There is limited level 5 evidence (Fung et al. 1990) that clonidine and cyproheptadine use in conjunction with BWSTT enhances walking ability in non-ambulatory incomplete SCI patients such that overground ambulation with assistive devices can be achieved.
There is level 4 evidence (Thrasher et al. 2006; Ladouceur and Barbeau 2000a; 2000b; Wieler et al. 1999; Klose et al. 1997; Granat et al. 1993; Stein et al. 1993; Granat et al. 1992) that FES-assisted walking can enhance walking speed and distance in complete and incomplete SCI.
There is level 4 evidence from 2 independent laboratories (Ladouceur and Barbeau 2000a,b; Wieler et al. 1999) that regular use of FES in gait training or activities of daily living leads to persistent improvement in walking function that is observed even when the stimulator is not in use.
There is level 1b evidence from one RCT (Kumru et al. 2013) that rTMS combined with overground locomotor training may not afford further benefits over overground locomotor training alone (with sham stimulation).
There is level 1b and level 2 evidence (Field-Fote & Roach, 2011; Field-Fote et al. 2005; Field-Fote and Tepavac 2002; Field-Fote 2001) for an overall enhancement of short-distance functional ambulation, as measured by overground gait speed over 6 meters, and walking distance when BWSTT was combined with FES of the common peroneal nerve.
There is level 1b evidence (Kressler et al. 2013) for increased benefit of electrical stimulation over manual assistance and braces (driven gait orthosis).
There is level 1b evidence (Hitzig et al. 2013) for a significant increase in SCIM mobility scores when subjects are stimulated with FES while ambulating on a BWS treadmill.
There is level 4 evidence from one pretest/posttest study (Hesse et al. 2004) suggesting that BWSTT combined with FES to the quadriceps and hamstrings muscles enhances functional ambulation.
There is level 4 evidence from one case series study (Triolo et al. 2012) that while an 8 channel neuroprosthesis system is safe and reliable, its use with rehabilitation training shows no statistically significant difference in walking outcomes.
There is level 2 evidence (Arazpour et al. 2013a) that PGOs can enable safe walking and reduce energy expenditure compared to passive bracing in patients with thoracic injuries.
There is level 4 evidence (see Table 14) that a reciprocating gait orthosis can enable walking in subjects with thoracic lesions, although not at speeds sufficient for community ambulation.
There is level 4 evidence (Yang et al. 1996) that a combined approach of bracing and FES results in additional benefit to functional ambulation in paraplegic patients with complete SCI. However, in subjects who achieve little benefit from bracing alone, the addition of FES appears to help improve standing or short-distance walking function (Marsolais et al. 2000). In incomplete SCI, however, there is some indication that a combination of bracing and FES provides greater ambulatory function than either approach alone (Kim et al. 2004).
There is limited level 4 evidence that WBV improves walking function (Ness & Field-Fote 2009).
There is level 2 evidence (1 low quality RCT) (Govil and Noohu 2013) that EMG biofeedback may improve gait outcomes in patients with SCI.
There is level 1b evidence (Field-Fote 2001) that most forms of locomotor training (i.e. including body weight supported treadmill training with various assists and FES-assisted overland training) increase lower limb muscle strength in chronic SCI as indicated by overall increases in total lower extremity motor scores.
There is level 3 evidence (Wernig et al. 1995) that body weight supported treadmill training is not significantly different than conventional rehabilitation therapy in enhancing lower limb muscle strength in acute SCI, although these studies are confounded by the natural recovery that may take place in the acute period.
There is level 4 evidence (Gregory et al. 2007) that a resistance and plyometric training program can enable improvements in overground gait speed in chronic incomplete SCI.