Effects of Therapeutic Ultrasound on Range of Motion and Stretch Pain

Abstract

[Purpose] This study aimed to clarify the effects of therapeutic ultrasound on range of motion and stretch pain and the relationships between the effects. [Subjects] The subjects were 15 healthy males. [Methods] Subjects performed all three interventions: (1) ultrasound (US group), (2) without powered ultrasound (placebo group), and (3) rest (control group). Ultrasound was applied at 3 MHz with an intensity of 1.0 W/cm2 and a 100% duty cycle for 10 minutes. The evaluation indices were active and passive range of motion (ROM), stretch pain (visual analog scale; VAS), and skin surface temperature (SST). The experimental protocol lasted a total of 40 minutes; this was comprised of 10 minutes before the intervention, 10 minutes during the intervention (US, placebo, and control), and 20 minutes after the intervention. [Results] ROM and SST were significantly higher in the US group than in the placebo and control groups for the 20 minutes after ultrasound, though there was no change in stretch pain. [Conclusion] The effects of ultrasound on ROM and SST were maintained for 20 minutes after the intervention. The SST increased with ultrasound and decreased afterwards. Additionally, the SST tended to return to baseline levels within 20 minutes after ultrasound exposure. Therefore, these effects were caused by a combination of thermal and mechanical effects of the ultrasound.

Regeneration of Skeletal Muscle After Eccentric Injury

“…While these in vitro and in vivo animal model studies have been somewhat informative, and would generally be predicted to reduce muscle regeneration and impair force production, often times the dose and extent of the cryotherapy or thermal ultrasound is much greater than what is used clinically, making it a challenge to directly apply these findings to patients. There have been some descriptive epidemiological studies that have looked at cryotherapy and thermal ultrasound in patients with muscle injuries, but these studies have produced conflicting results on the efficacy of these modalities in improving patient outcomes 48,49,53,60–62 . Further animal studies using more clinically relevant temperature changes and larger epidemiological studies in patients with muscle strain injuries, could further enhance the evidence-based application of these modalities in the sports medicine setting.…”

Comparison of therapeutic duration of therapeutic ultrasound in patients with knee osteoarthritis

“…Several studies compare US and physical therapy versus placebo for patients with knee OA, but the clinical efficacy of US remains controversial 2 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ) . Despite these results, US therapeutic acoustic radiation is still very popular for the treatment of musculoskeletal disorders and it has been asserted that it reduces edema, relieves pain, and increases range of motion 12–14) .…”

Comparison of the effects of hamstring stretching using proprioceptive neuromuscular facilitation with prior application of cryotherapy or ultrasound therapy

“…The evaluation indices were active and passive ROM, stretch pain (visual analog scale; VAS), and skin surface temperature (SST). The results showed there were significant increases in ROM and SST after ultrasound, without any change in stretch pain 29 ) . In our study, we opted to use ultrasound at 1 MHz due to its depth of action and the localization of the target muscle.…”