ABSTRACT
OBJECTIVE: The purpose of this study was to examine associations between level of kinesiophobia and improvement in physical function during recovery from lower extremity injury. METHODS: A total 430 adults (mean [SD]: age = 27.3 [6.4] years; sex = 70.5% men; body mass index = 27.6 [5.2] kg/m2) were included in the analyses. Using the Patient-Reported Outcomes Measurement Information System, physical function was evaluated in parallel with treatment from a physical therapist at the initial visit and every 3 weeks until final visit or up to 6 months. A Tampa Scale of Kinesiophobia (TSK-17) score of >41 indicated elevated TSK. Four TSK groups were identified: (1) TSK score improved from >41 at initial visit to <41 by final visit (TSK_I), (2) TSK score was <41 at initial and final visits (TSK-), (3) TSK score was >41 at initial and final visits (TSK+), and (4) TSK score worsened from <41 at initial visit to ≥41 by final visit (TSK_W). Linear mixed effects models were used to examine differences between groups in improved physical function over time, with adjustment for depression and self-efficacy. RESULTS: Groups with elevated kinesiophobia at the final visit had smaller positive improvements in physical function (mean change [95% CI]: TSK+ = 7.1 [4.8-9.4]; TSK_W: 6.0 [2.6-9.4]) compared with groups without elevated kinesiophobia at the final visit (TSK_I = 9.8 [6.4-13.3]; TSK- = 9.7 [8.1-11.3]) by 12 weeks. CONCLUSIONS: Elevated kinesiophobia that persists or develops over the course of care is associated with less improvement in physical function within military and civilian cohorts. IMPACT: The findings of this prospective longitudinal study support the need to assess for elevated kinesiophobia throughout the course of care because of its association with decreased improvement in physical function. LAY SUMMARY: To help improve your physical function, your physical therapist can monitor the interaction between fear of movement and your clinical outcomes over the course of treatment.
Subject(s)
Leg Injuries/psychology , Leg Injuries/rehabilitation , Phobic Disorders/physiopathology , Physical Therapy Modalities/psychology , Recovery of Function , Adult , Behavior Rating Scale , Fear/psychology , Female , Humans , Linear Models , Longitudinal Studies , Lower Extremity/physiopathology , Male , Military Personnel/psychology , Patient Reported Outcome Measures , Phobic Disorders/etiology , Prospective StudiesABSTRACT
The adaptive range of 1/f dynamics in isometric force output was investigated. Participants produced isometric force to targets with predictable demands (constant and sinusoidal) and 1/f noise waveforms (white, pink, brown, and black) that also varied in the frequency bandwidth represented in the force signal (0-4 Hz, 0-8 Hz, and 0-12 Hz). The range of within-trial 1/f force dynamics produced was between darker than pink noise and lighter than black noise according to task conditions. The exponent of the respective 1/f force dynamics decreased as the frequency bandwidth of the force signal increased. The findings reveal an adaptive though restricted range of 1/f force variation that is modulated by the dynamics of the task constraints.
Subject(s)
Isometric Contraction/physiology , Muscle Strength/physiology , Muscle, Skeletal/physiology , Adaptation, Physiological , Adult , Analysis of Variance , Female , Fractals , Humans , Male , Reference Values , Task Performance and Analysis , Young AdultABSTRACT
The purpose of the current experiment was to investigate the amount (standard deviation (S.D.) and coefficient of variation (CV)) and structure (approximate entropy (ApEn)) of force variability at very low force levels. Participants produced isometric force output of index finger abduction at five levels (0.4, 0.8, 1.0, 2.0, and 4.0 N) with high and low visual feedback gain. The findings showed that: subjects scaled their force output to the targets; S.D. increased non-linearly with force level and decreased with visual gain; and CV decreased with force level as well as visual gain. ApEn of the force output did not change as a function of force level, although the high gain increased ApEn in contrast to low gain. It is proposed that the recruitment of additional motor units at very low force levels does not significantly alter the structure of the force output, although it does increase the magnitude of force and its amount of variability. Overall, the findings provide evidence that the amount and structure of motor variability can be influenced by separate control processes at low force levels.
