Table 1 Outline of the gait event detection algorithms compared in this study

Position

Y

HEE, SACR

FS: Maximum of antero-posterior position difference between Heel and Sacrum

Zeni et al. [5]

TOE, SACR

FO: Minimum of antero-posterior position difference between fore-foot (Toe) and Sacrum

Y

HEE

FS: Maximum of high-filtered antero-posterior Heel position

Desailly et al. [4]

TOE

FO: Minimum of high-filtered antero-posterior Toe position

Velocity

Z

HEE, TOE

FS: Minimum of foot virtual centre (Heel–Toe middle) vertical speed

O’Connor et al. [8]

HEE, TOE

FO: Maximum of foot virtual centre (Heel–Toe middle) vertical speed

Sagittal

(Y, Z)

HEE

FS: Sagittal speed under threshold :

• Ghoussayni: 500 mm/s

• Modified Ghoussayni: 0.78 * walking speed

Ghoussayni et al. [7]

Modified Ghoussayni: Bruening et al. [11]

TOE

FO: Sagittal speed above threshold :

• Ghoussayni: 500 mm/s

• Modified Ghoussayni: 0.66 * walking speed

3D

HEE, TOE

FS: pre-detection with Zeni

Pre-processing with 3D speed under threshold:

• Heel: 0.5 * walking speed

• Fore-foot: 0.8 * walking speed

Bonci et al. [6]

TOE

FO: pre-detection with Zeni

Pre-processing with 3D speed above threshold:

• Fore-foot: 0.8 * walking speed

HEE, ANK, TOE, VMH,

SMH, FMH, HLX

FS: First of seven foot markers whose speed in each of 3 components is lower than fractions of the mean antero-posterior walking speed

Multi-Condition algorithm

FO: Last of seven foot markers whose speed in each of 3 components is higher than fractions of the mean antero-posterior walking speed

Acceleration

Z

HEE

FS: Maximum of Heel vertical acceleration

Hreljac and Marshall [9]

Y

TOE

FO: Maximum of Toe antero-posterior acceleration

Y

HEE

FS: Minimum of antero-posterior Heel acceleration

Hsue et al. [10]

TOE

FO: Maximum of Toe antero-posterior acceleration