Real maximum walking speed assessed by a corrected

P654

26th Congress of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS), Gothenburg, Sweden, 13 – 16 October 2010

Real maximum walking speed on short distance assessed by a corrected version of the Timed 25 Foot Walk Test (T25FW) R. Phan Ba1, 2, P. Calay1, 2, P. Grodent1, 3, G. Delrue1,2, G. Moonen2, G. Nagels4, S. Belachew1, 2

1: MYelin Disorders REseArch teaM (MYDREAM), C.H.U. de Liege (Liege, BE); 2: Dept. of Neurology, C.H.U. de Liege (Liege, BE); 3: Dept. of Physical Medicine and Rehabilitation, C.H.U. de Liege (Liege, BE); 4: National Center For Multiple Sclerosis (Melsbroek, BE)

Fig. 1

Table 1: Characteristics of patients and control subjects MS patients

Healthy Controls

Number of patients/controls

51

30

Gender (% female)

63

71

37,2  10,4, 15-64

29,7  10,1, 18-60

Age (mean  SD, range) EDSS (median, range)

2.5, 0-4.5

MS subtype (CIS/RR/progressive)

5/42/4

Disease duration (year, median, range)

5, 1-35

MWD in metres (median, range) Patients with limited ambulation1: Number (%)

1000, 300-1700 13 (25.4)

1. Limited ambulation was defined as the inability to walk more than 4000 m; 2. MWD: Maximum Walking Distance.

Background: Analysis of ambulation is a crucial component of the functional status and reflects disability progression in multiple sclerosis (MS) patients. The Timed 25 Foot Walk Test (T25FW) is the more widely used test in clinical trials to measure the potential impact of therapies on ambulation performances1, 2 and was considered to represent the maximum walking speed (WS) patients can reach3. However, we have previously shown that the T25FW test is not an accurate measure of the maximum WS, since we demonstrated that the mean WS was paradoxically higher when measured over a longer distance of 100 meters compared to that of the classical short distance of 25 foot4. We also showed that as much as 30% of the MS population though considered fully ambulatory according to the EDSS rules could display early locomotor impairment with significant maximum walking distance restrictions. The failure of the T25FW to represent the maximum WS might be explained by several potential limitations5, including patients’ ability to accelerate and the time and distance it takes to reach their maximum pace, which are influenced by multiple factors, such as the motivation, the tester’s training and perhaps early MS-related motor and cognitive disability.

Fig. 2

Objective: To develop a new version of the T25FW removing this fluctuant phase of initial acceleration that makes it a poor indicator of the accurate maximum WS on a short distance. Methods: In 51 ambulatory MS patients (EDSS ≤ 4.5 and maximum walking distance ≥ 300 m without aid or rest) and 30 healthy control volunteers (Table 1), we measured the T25FW, as previously described1, 2 and the socalled corrected T25FW (T25FW+) where the subjects performed the T25FW following the standard guidelines except that they were asked to take a run-up of 3 meters behind the starting line allowing them to possibly reach their maximum WS at the time they crossed the line and triggered the stopwatch. Statistical analysis (student t-tests, pearson r correlation coefficient) were then performed using GraphPad Prism, version 4.0b for Macintosh, GraphPad Software, San Diego California USA (www.graphpad.com).

Fig. 3

Results: In both healthy control volunteers and MS patients, the two tests displayed a good correlation (r=0,8554 and 0,9480, both p