The evolution of walking-related outcomes over the first 12 weeks of rehabilitation for incomplete traumatic spinal cord injury: the multicenter randomized Spinal Cord Injury Locomotor Trial

Abstract

Background: The Spinal Cord Injury Locomotor Trial (SCILT) compared 12 weeks of step training with body weight support on a treadmill (BWSTT) that included overground practice to a defined but more conventional overground mobility intervention (CONT) in patients with incomplete traumatic SCI within 8 weeks of onset. No previous studies have reported walking-related outcomes during rehabilitation.

Methods: This single-blinded, randomized trial entered 107 American Spinal Injury Association (ASIA) C and D patients and 38 ASIA B patients with lesions between C5 and L3 who were unable to walk on admission for rehabilitation. The Functional Independence Measure (FIM-L) for walking, 15-m walking speed, and lower extremity motor score (LEMS) were collected every 2 weeks.

Results: No significant differences were found at entry and during the treatment phase (12-week mean FIM-L = 5, velocity = 0.8 m/s, LEMS = 35, distance walked in 6 min = 250 m). Combining the 2 arms, a FIM-L >or= 4 was achieved in < 10% of ASIA B patients, 92% of ASIA C patients, and all of ASIA D patients. Walking speed of >or= 0.6 m/s correlated with a LEMS near 40 or higher.

Conclusions: Few ASIA B and most ASIA C and D patients achieved functional walking ability by the end of 12 weeks of BWSTT and CONT, consistent with the primary outcome data at 6 months. Walking-related measures assessed at 2-week intervals reveal that time after SCI is an important variable for entering patients into a trial with mobility outcomes. By about 6 weeks after entry, most patients who will recover have improved their FIM-L to >3 and are improving in walking speed. Future trials may reduce the number needed to treat by entering patients with FIM-L < 4 at > 8 weeks after onset if still graded ASIA B and at > 12 weeks if still ASIA C.

Figures

Figure 1

Changes in the (A) Functional Independence Measure–Locomotor (FIM-L) score, (B) walking speed, and (C) lower extremity motor score (LEMS) measured biweekly over 12 weeks of either body weight–supported treadmill training or the control mobility training for ASIA B patients. The number of patients is found in Table 1. Poor outcomes were found for both treatment groups in the trial. The vertical bars represent the standard error. TX = treatment group; BWSTT = body weight–supported treadmill training.

Figure 2

Changes in the (A) Functional Independence Measure–Locomotor (FIM-L) score, (B) walking speed, and (C) lower extremity motor score (LEMS) measured biweekly over 12 weeks of either body weight–supported treadmill training or the control mobility training for American Spinal Injury Association (ASIA) C and D patients. The number of patients is found in Table 2. The vertical bars represent the standard error. TX = treatment group; BWSTT = body weight–supported treadmill training.

Figure 3

Piecewise regression analysis of walking speed in relation to the lower extremity motor score (LEMS) at the end of training reveals that a slow but functional walking speed of 0.60 m/s tended to be reached as the LEMS approached 40 and then increased to more functional velocities as the LEMS exceeded 40.