Detect circumduction (excessive lateral swing trajectory)

Circumduction is a lateral (outward) swing of the foot/hip used to advance a functionally long limb (e.g. with stiff knee or drop foot). It is quantified as the peak lateral excursion of the foot (or hip) during swing relative to the stance-phase baseline.

Usage

detectCircumduction(
  foot_ml,
  swing = c(60, 100),
  stance = c(0, 55),
  threshold = 0.04,
  severe = 0.12,
  lateral_sign = 1
)

Arguments

foot_ml

Medio-lateral foot (or hip) position over one gait cycle, in metres, with lateral being positive (see lateral_sign).

swing, stance

Percentage windows of swing and stance (defaults c(60, 100) and c(0, 55)).

threshold

Lateral excursion (m) above which circumduction is flagged (default 0.04).

severe

Lateral excursion mapped to severity 1 (default 0.12 m).

lateral_sign

+1 if positive foot_ml is lateral, -1 otherwise.

Value

A gait_pattern_flag object.

References

Perry J, Burnfield JM (2010); Kerrigan DC, et al. (2000).

See also

classifyGaitPatterns()