Subjective experiences of men with and without spinal cord injury: tolerability of the juvent and WAVE whole body vibration plates.

BACKGROUND

Device tolerability is an important determinant of subject adherence and intervention effectiveness. Although popular in rehabilitation settings, the tolerability of whole-body vibration (WBV) among patients with spinal cord injury (SCI) is unknown.

OBJECTIVE

To assess feedback from SCI and non-SCI subjects on the usability of passive standing and WBV devices (Juvent [Juvent Medical, Somerset, NJ] and WAVE [WAVE Manufacturing, Windsor, Ontario, Canada]) using a priori specified knee postures, plate amplitudes, and frequencies.

DESIGN

A matched groups design with repeated measures.

SETTING

A tertiary SCI rehabilitation center.

SUBJECTS

Eight men with chronic SCI (C4-L2, American Spinal Injury Association Impairment Scale A-D) and 10 men without SCI of similar height, weight, and body mass index.

INTERVENTION

Subjects (N = 18; 8 with SCI) underwent intermittent WBV during passive standing (EasyStand 5000 [Altimate Medical, Morton, MN]) for 45 minutes using the optimized WAVE and Juvent plates. WBV parameters were sequentially altered every 2 minutes and included parameter combinations of (1) postures of 140°, 160°, and 180° knee extension (180° with Juvent only); (2) amplitudes of 0.7 mm and 1.1 mm (WAVE only); and (3) frequencies of 25 Hz, 35 Hz, and 45 Hz. Outcome assessments were completed at 4-minute intervals throughout WBV exposure.

MAIN OUTCOME MEASURES

Qualitative, semistructured interviews were used to generate neutral, positive, and negative descriptors of the subjects' overall experience and device preference.

RESULTS

SCI subjects reported a greater frequency of positive descriptors than non-SCI subjects during WBV, regardless of plate, posture, amplitude, or frequency, with the exception of 1 combination of parameters (WAVE plate at 140°, 1.1 mm, and 25 Hz). Non-SCI subjects reported the highest frequency of negative effects with the WAVE plate at 160°, 1.1 mm, 25 Hz, and 35 Hz. Non-SCI subjects preferred the Juvent, whereas SCI subjects preferred the WAVE plate.

CONCLUSIONS

SCI and non-SCI subjects reported differing frequencies of positive and negative descriptors and indicated divergent device preferences. SCI subjects preferred the WAVE plate and vibration at high frequency. Future research will determine the therapeutic potential and adverse events associated with the device and WBV parameters tolerable for persons with SCI.