Sensorimotor system measurement techniques

Abstract

Objective: To provide an overview of currently available sensorimotor assessment techniques.

Data sources: We drew information from an extensive review of the scientific literature conducted in the areas of proprioception, neuromuscular control, and motor control measurement. Literature searches were conducted using MEDLINE for the years 1965 to 1999 with the key words proprioception, somatosensory evoked potentials, nerve conduction testing, electromyography, muscle dynamometry, isometric, isokinetic, kinetic, kinematic, posture, equilibrium, balance, stiffness, neuromuscular, sensorimotor, and measurement. Additional sources were collected using the reference lists of identified articles.

Data synthesis: Sensorimotor measurement techniques are discussed with reference to the underlying physiologic mechanisms, influential factors and locations of the variable within the system, clinical research questions, limitations of the measurement technique, and directions for future research.

Conclusions/recommendations: The complex interactions and relationships among the individual components of the sensorimotor system make measuring and analyzing specific characteristics and functions difficult. Additionally, the specific assessment techniques used to measure a variable can influence attained results. Optimizing the application of sensorimotor research to clinical settings can, therefore, be best accomplished through the use of common nomenclature to describe underlying physiologic mechanisms and specific measurement techniques.

Figure 1

The proprioception testing device is a motor-driven jig used to test both position sense and kinesthesia. Subjects are fitted with a blindfold, headset containing white noise, and pneumatic sleeve to negate visual, audio, and tactile cues.

Figure 2

The electromagnetic motion tracking device is used to assess position sense and replicate movement patterns and for 3-dimensional kinematic analysis of movement.

Figure 3

A, Dual fine-wire electrode used for electromyographic assessment of muscle activity. B, Electrode insertion for assessment of deep muscles; the supraspinatus muscle is shown.

Figure 4

Raw electromyographic signal (A) that has been full-wave rectified (B), smoothed using a 10-Hz low-pass filter (C), and amplitude normalized to a maximum voluntary contraction (D).

Figure 5

A, Ankle perturbation device used to assess muscle reflex characteristics of the ankle joint. B, Typical muscle reflex characteristics during an inversion perturbation trial.

Figure 6

A, Electromyographic analysis of the lower leg muscles during a gait activity on a treadmill. B, Phase delineation of typical muscle activity during gait.

Figure 7

A, Assessment of ground reaction forces during a landing task. B, Typical vertical ground reaction forces during landing.

Figure 8

A, Kinematic analysis of the golf swing using a high-speed video camera system. B, Three-dimensional representation of the golf swing for kinematic analysis.

Figure 9

Multivariate assessment of postural control using force plate, electromyographic, and motion analysis.

Figure 10

A, Ankle joint stiffness assessed during passive movement using position data from an isokinetic dynamometer and torque data from an externally fixed load cell. B, Typical joint stiffness derived from the slope of the position versus torque data.